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Zhou S, Xu K, Fang Y, Alastruey J, Vennin S, Yang J, Wang J, Xu L, Wang X, Greenwald SE. Patient-specific non-invasive estimation of the aortic blood pressure waveform by ultrasound and tonometry. Comput Methods Programs Biomed 2024; 247:108082. [PMID: 38422893 DOI: 10.1016/j.cmpb.2024.108082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/21/2024] [Accepted: 02/14/2024] [Indexed: 03/02/2024]
Abstract
BACKGROUND AND OBJECTIVE Aortic blood pressure (ABP) is a more effective prognostic indicator of cardiovascular disease than peripheral blood pressure. A highly accurate algorithm for non-invasively deriving the ABP wave, based on ultrasonic measurement of aortic flow combined with peripheral pulse wave measurements, has been proposed elsewhere. However, it has remained at the proof-of-concept stage because it requires a priori knowledge of the ABP waveform to calculate aortic pulse wave velocity (PWV). The objective of this study is to transform this proof-of-concept algorithm into a clinically feasible technique. METHODS We used the Bramwell-Hill equation to non-invasively calculate aortic PWV which was then used to reconstruct the ABP waveform from non-invasively determined aortic blood flow velocity, aortic diameter, and radial pressure. The two aortic variables were acquired by an ultrasound system from 90 subjects, followed by recordings of radial pressure using a SphygmoCor device. The ABPs estimated by the new algorithm were compared with reference values obtained by cardiac catheterization (invasive validation, 8 subjects aged 62.3 ± 12.7 years) and a SphygmoCor device (non-invasive validation, 82 subjects aged 45.0 ± 17.8 years). RESULTS In the invasive comparison, there was good agreement between the estimated and directly measured pressures: the mean error in systolic blood pressure (SBP) was 1.4 ± 0.8 mmHg; diastolic blood pressure (DBP), 0.9 ± 0.8 mmHg; mean blood pressure (MBP), 1.8 ± 1.2 mmHg and pulse pressure (PP), 1.4 ± 1.1 mmHg. In the non-invasive comparison, the estimated and directly measured pressures also agreed well: the errors being: SBP, 2.0 ± 1.4 mmHg; DBP, 0.8 ± 0.1 mmHg; MBP, 0.1 ± 0.1 mmHg and PP, 2.3 ± 1.6 mmHg. The significance of the differences in mean errors between calculated and reference values for SBP, DBP, MBP and PP were assessed by paired t-tests. The agreement between the reference methods and those obtained by applying the new approach was also expressed by correlation and Bland-Altman plots. CONCLUSION The new method proposed here can accurately estimate ABP, allowing this important variable to be obtained non-invasively, using standard, well validated measurement techniques. It thus has the potential to relocate ABP estimation from a research environment to more routine use in the cardiac clinic. SHORT ABSTRACT A highly accurate algorithm for non-invasively deriving the ABP wave has been proposed elsewhere. However, it has remained at the proof-of-concept stage because it requires a priori knowledge of the ABP waveform to calculate aortic pulse wave velocity (PWV). This study aims to transform this proof-of-concept algorithm into a clinically feasible technique. We used the Bramwell-Hill equation to non-invasively calculate aortic PWV which was then used to reconstruct the ABP waveform. The ABPs estimated by the new algorithm were compared with reference values obtained by cardiac catheterization or a SphygmoCor device. The results showed that there was good agreement between the estimated and directly measured pressures. The new method proposed can accurately estimate ABP, allowing this important variable to be obtained non-invasively, using standard, well validated measurement techniques. It thus has the potential to relocate ABP estimation from a research environment to more routine use in the cardiac clinic.
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Affiliation(s)
- Shuran Zhou
- College of Medicine and Biological Information Engineering, Northeastern University, Shenyang 110169, China; Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an 710032, China
| | - Kai Xu
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang 110840, China.
| | - Yi Fang
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang 110840, China
| | - Jordi Alastruey
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Samuel Vennin
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Jun Yang
- Department of Cardiovascular Ultrasound, the First Hospital of China Medical University, Shenyang 110122, China
| | - Junli Wang
- Department of Cardiovascular Ultrasound, the First Hospital of China Medical University, Shenyang 110122, China
| | - Lisheng Xu
- College of Medicine and Biological Information Engineering, Northeastern University, Shenyang 110169, China; Engineering Research Center of Medical Imaging and Intelligent Analysis, Ministry of Education, Shenyang 110169, China; Neusoft Research of Intelligent Healthcare Technology, Co. Ltd., Shenyang 110169, China.
| | - Xiaocheng Wang
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an 710032, China
| | - Steve E Greenwald
- Blizard Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London E1 4NS, United Kingdom
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Huang Y, Tang Y, Liang Y, Xie Z, Wu J, Huang J, Wei S, Nie S, Jiang T. Transport and retention of n-hexadecane in cadmium-/naphthalene-contaminated calcareous soil sampled in a karst area. Environ Geochem Health 2023; 45:8881-8895. [PMID: 37358714 DOI: 10.1007/s10653-023-01664-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 06/13/2023] [Indexed: 06/27/2023]
Abstract
Studying the transport of petroleum hydrocarbons in cadmium-/naphthalene-contaminated calcareous soils is crucial to comprehensive assessment of environmental risks and developing appropriate strategies to remediate petroleum hydrocarbons pollution in karst areas. In this study, n-hexadecane was selected as a model petroleum hydrocarbon. Batch experiments were conducted to explore the adsorption behavior of n-hexadecane on cadmium-/naphthalene-contaminated calcareous soils at various pH, and column experiments were performed to investigate the transport and retention of n-hexadecane under various flow velocity. The results showed that Freundlich model better described the adsorption behavior of n-hexadecane in all cases (R2 > 0.9). Under the condition of pH = 5, it was advantageous for soil samples to adsorb more n-hexadecane, and the maximum adsorption content followed the order of: cadmium/naphthalene-contaminated > uncontaminated soils. The transport of n-hexadecane in cadmium/naphthalene-contaminated soils at various flow velocity was well described by two kinetic sites model of Hydrus-1D with R2 > 0.9. Due to the increased electrostatic repulsion between n-hexadecane and soil particles, n-hexadecane was more easily able to breakthrough cadmium/naphthalene-contaminated soils. Compared to low flow velocity (1 mL/min), a higher concentration of n-hexadecane was determined at high flow velocity, with 67, 63, and 45% n-hexadecane in effluent from cadmium-contaminated soils, naphthalene-contaminated soils, and uncontaminated soils, respectively. These findings have important implications for the government of groundwater in calcareous soils from karst areas.
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Affiliation(s)
- Yiting Huang
- School of Civil Engineering and Architecture, Guangxi University, Nanning, 530004, China
| | - Yankui Tang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
| | - Yi Liang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Zhenze Xie
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Jipeng Wu
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Jiajie Huang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Shanxiong Wei
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Shaojiang Nie
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Tao Jiang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
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Liu L, Li Y, Zhang J, Niu D, Wang J, Tang J. Influence of hydrodynamic conditions on the fate of halogenated flame retardants along salinity gradients in a highly polluted micro-tidal estuary. Sci Total Environ 2023:164716. [PMID: 37301402 DOI: 10.1016/j.scitotenv.2023.164716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 06/04/2023] [Accepted: 06/05/2023] [Indexed: 06/12/2023]
Abstract
Halogenated flame retardants (HFRs) have properties similar to those of hydrophobic organic pollutants (HOPs). However, the understanding of their environmental fate in tidal estuaries remains limited. This study aims to bridge knowledge gaps regarding the land-sea transport of HFRs through riverine discharge into coastal waters. HFR levels were significantly influenced by tidal movement, and decabromodiphenyl ethane (DBDPE) was the predominant compound with a median concentration of 3340 pg L-1 in the Xiaoqing River estuary (XRE), whereas BDE209 had a median concentration of 1370 pg L-1. The Mihe River tributary plays a key role in transporting pollution to the downstream estuary of the XRE in summer, and the increasing suspended particulate matter (SPM) by resuspension in winter significantly affects HFR levels. These concentrations were inversely proportional to diurnal tidal oscillations. Tidal asymmetry caused an increase in SPM during an ebb tide, which increased HFR levels in a micro-tidal estuary such as the Xiaoqing River. The location of the point source and flow velocity influences the HFR concentrations during tidal fluctuations. Tidal asymmetry increases the likelihood of some HFRs being adsorbed by particles exported to the adjacent coast, and some settled down in areas with low hydrodynamic conditions, hindering their flow to the ocean.
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Affiliation(s)
- Lin Liu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266525, China; CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Shandong Key Laboratory of Coastal Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Yanfang Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Shandong Key Laboratory of Coastal Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Jian Zhang
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Shandong Key Laboratory of Coastal Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Donglei Niu
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Shandong Key Laboratory of Coastal Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiakai Wang
- Key Laboratory of Marine Geology and Metallogeny, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China
| | - Jianhui Tang
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Shandong Key Laboratory of Coastal Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
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Kim JH, Yoo RE, Choi SH, Park SH. Non-invasive flow mapping of parasagittal meningeal lymphatics using 2D interslice flow saturation MRI. Fluids Barriers CNS 2023; 20:37. [PMID: 37237402 DOI: 10.1186/s12987-023-00446-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 05/21/2023] [Indexed: 05/28/2023] Open
Abstract
The clearance pathways of brain waste products in humans are still under debate in part due to the lack of noninvasive imaging techniques for meningeal lymphatic vessels (mLVs). In this study, we propose a new noninvasive mLVs imaging technique based on an inter-slice blood perfusion MRI called alternate ascending/descending directional navigation (ALADDIN). ALADDIN with inversion recovery (IR) at single inversion time of 2300 ms (single-TI IR-ALADDIN) clearly demonstrated parasagittal mLVs around the human superior sagittal sinus (SSS) with better detectability and specificity than the previously suggested noninvasive imaging techniques. While in many studies it has been difficult to detect mLVs and confirm their signal source noninvasively, the detection of mLVs in this study was confirmed by their posterior to anterior flow direction and their velocities and morphological features, which were consistent with those from the literature. In addition, IR-ALADDIN was compared with contrast-enhanced black blood imaging to confirm the detection of mLVs and its similarity. For the quantification of flow velocity of mLVs, IR-ALADDIN was performed at three inversion times of 2000, 2300, and 2600 ms (three-TI IR-ALADDIN) for both a flow phantom and humans. For this preliminary result, the flow velocity of the dorsal mLVs in humans ranged between 2.2 and 2.7 mm/s. Overall, (i) the single-TI IR-ALADDIN can be used as a novel non-invasive method to visualize mLVs in the whole brain with scan time of ~ 17 min and (ii) the multi-TI IR-ALADDIN can be used as a way to quantify the flow velocity of mLVs with a scan time of ~ 10 min (or shorter) in a limited coverage. Accordingly, the suggested approach can be applied to noninvasively studying meningeal lymphatic flows in general and also understanding the clearance pathways of waste production through mLVs in humans, which warrants further investigation.
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Affiliation(s)
- Jun-Hee Kim
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Roh-Eul Yoo
- Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea
- Department of Radiology, Seoul National University Hospital, Seoul, South Korea
| | - Seung Hong Choi
- Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea
- Department of Radiology, Seoul National University Hospital, Seoul, South Korea
| | - Sung-Hong Park
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea.
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Zhu T, Yang R, Xiao R, Liu L, Zhu S, Zhao J, Ye Z. Effects of flow velocity on the growth performance, antioxidant activity, immunity and intestinal health of Chinese Perch (Siniperca chuatsi) in recirculating aquaculture systems. Fish Shellfish Immunol 2023; 138:108811. [PMID: 37169108 DOI: 10.1016/j.fsi.2023.108811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/04/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
The cultivation of Chinese Perch (Siniperca chuatsi) in recirculating aquaculture systems (RASs) has become a common trend. To explore the effect of flow velocity on the growth performance, antioxidant activity, immunity and intestinal health of Chinese Perch in RAS, 240 Chinese Perch with an initial weight of 70.66 ± 0.34 g were selected and randomly divided into 4 groups: control group [CK, 0 body length per second (bl/s)], low flow velocity (LF, 0.4 bl/s), middle flow velocity (MF, 0.8 bl/s) and high flow velocity (HF, 1.2 bl/s) for a 56-days experiment. The results showed that the flow velocity significantly increased the weight gain rate and feed intake in Chinese Perch. At 1.2 bl/s, the flow velocity increased the intestinal trypsin content and intestinal villus length. Furthermore, the relative expression of appetite-related genes showed a tendency to increase, and the relative expression of appetite-inhibiting genes had a significant decrease in HF. Regarding immune-related indicators, the activities of alanine aminotransferase (ALT) and aspartate transaminase (AST) were significantly higher in MF and HF. However, the activities of lysozyme (LZM) significantly decreased. Moreover, the activities of total superoxide dismutase (T-SOD) and catalase (CAT) were significantly higher in the CK group than in the other groups. Excessive flow velocity also caused the mRNA level of most immune-relevant genes to markedly decrease. With regard to intestinal health, the intestinal content sequencing results showed that MF could increase the intestinal diversity index of Chinese Perch. In addition, with increasing flow velocity, the relative abundance of Proteobacteria gradually increased, while the proportion of Firmicutes decreased. In conclusion, although the high flow velocity could promote growth, feeding, and digestion, inhibit fat deposition and increase the intestinal microbial abundance, the flow velocity caused stress, which leads to a decline in immunity and increases the death rate and the risk of intestinal disease in Chinese Perch. These findings provide theoretical support for the development of RASs for Chinese Perch.
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Affiliation(s)
- Tingyao Zhu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, China
| | - Ru Yang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Runguo Xiao
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, China
| | - Liwei Liu
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Songming Zhu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, China; Ocean Academy, Zhejiang University, Zhoushan, 316000, China
| | - Jian Zhao
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, China.
| | - Zhangying Ye
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, China; Ocean Academy, Zhejiang University, Zhoushan, 316000, China.
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Wen J, Duan L, Wang B, Dong Q, Liu Y, Huang J, Yu G. Stability and WBE biomarkers possibility of 17 antiviral drugs in sewage and gravity sewers. Water Res 2023; 238:120023. [PMID: 37150064 PMCID: PMC10149109 DOI: 10.1016/j.watres.2023.120023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/31/2023] [Accepted: 04/28/2023] [Indexed: 05/09/2023]
Abstract
Wastewater-based epidemiology (WBE) is a promising technique for monitoring the rapidly increasing use of antiviral drugs during the COVID-19 pandemic. It is essential to evaluate the in-sewer stability of antiviral drugs in order to determine appropriate biomarkers. This study developed an analytical method for quantification of 17 typical antiviral drugs, and investigated the stability of target compounds in sewer through 4 laboratory-scale gravity sewer reactors. Nine antiviral drugs (lamivudine, acyclovir, amantadine, favipiravir, nevirapine, oseltamivir, ganciclovir, emtricitabine and telbivudine) were observed to be stable and recommended as appropriate biomarkers for WBE. As for the other 8 unstable drugs (abacavir, arbidol, ribavirin, zidovudine, ritonavir, lopinavir, remdesivir and efavirenz), their attenuation was driven by adsorption, biodegradation and diffusion. Moreover, reaction kinetics revealed that the effects of sediments and biofilms were regarded to be independent in gravity sewers, and the rate constants of removal by biofilms was directly proportional to the ratio of surface area against wastewater volume. The study highlighted the potential importance of flow velocity for compound stability, since an increased flow velocity significantly accelerated the removal of unstable biomarkers. In addition, a framework for graded evaluation of biomarker stability was proposed to provide reference for researchers to select suitable WBE biomarkers. Compared with current classification method, this framework considered the influences of residence time and different removal mechanisms, which additionally screened four antiviral drugs as viable WBE biomarkers. This is the first study to report the stability of antiviral drugs in gravity sewers.
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Affiliation(s)
- Jiaqi Wen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory for Emerging Organic Contaminants Control, Beijing Laboratory for Environmental Frontier Technologies, China
| | - Lei Duan
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory for Emerging Organic Contaminants Control, Beijing Laboratory for Environmental Frontier Technologies, China
| | - Bin Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory for Emerging Organic Contaminants Control, Beijing Laboratory for Environmental Frontier Technologies, China
| | - Qian Dong
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanchen Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jun Huang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory for Emerging Organic Contaminants Control, Beijing Laboratory for Environmental Frontier Technologies, China
| | - Gang Yu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory for Emerging Organic Contaminants Control, Beijing Laboratory for Environmental Frontier Technologies, China; Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University at Zhuhai, 519087, China.
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Ma X, Li Y, Niu L, Shang J, Yang N. Microbial community structure and denitrification responses to cascade low-head dams and their contribution to eutrophication in urban rivers. Environ Res 2023; 221:115242. [PMID: 36634891 DOI: 10.1016/j.envres.2023.115242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/03/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Low-head dams are one of the most common hydraulic facilities, yet they often fragment rivers, leading to profound changes in aquatic biodiversity and river eutrophication levels. Systematic assessments of river ecosystem structure and functions, and their contribution to eutrophication, are however lacking, especially for urban rivers where low-head dams prevail. In this study, we address this gap with a field survey on microbial community structure and ecosystem function, in combination with hydrological, environmental and ecological factors. Our findings revealed that microbial communities showed significant differences among the cascade impoundments, which may be due to the environment heterogeneity resulting from the cascade low-head dams. The alternating lentic-lotic flow environment created by the low-head dams caused nutrient accumulation in the cascade impoundments, enhancing environmental sorting and interspecific competition relationships, and thus possibly contributing to the reduction in sediment denitrification function. Decreased denitrification led to excessive accumulation of nutrients, which may have aggravated river eutrophication. In addition, structural equation model analysis showed that flow velocity may be the key controlling factor for river eutrophication. Therefore, in the construction of river flood control and water storage systems, the location, type and water storage capacity of low-head dams should be fully considered to optimize the hydrodynamic conditions of rivers. To summarize, our findings revealed the cumulative effects of cascade low-head dams in an urban river, and provided new insights into the trade-off between construction and decommissioning of low-head dams in urban river systems.
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Affiliation(s)
- Xin Ma
- College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, PR China; Research Institute of Mulan Ecological River, Putian, 351100, PR China
| | - Yi Li
- College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, PR China; Research Institute of Mulan Ecological River, Putian, 351100, PR China.
| | - Lihua Niu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China; Research Institute of Mulan Ecological River, Putian, 351100, PR China.
| | - Jiahui Shang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Nan Yang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
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Wang RL, Gingrich KJ, Vance A, Johnson MD, Welch BG, McDonagh DL. The effects of aneurysmal subarachnoid hemorrhage on cerebral vessel diameter and flow velocity. J Stroke Cerebrovasc Dis 2023; 32:107056. [PMID: 36933521 DOI: 10.1016/j.jstrokecerebrovasdis.2023.107056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 02/05/2023] [Accepted: 02/07/2023] [Indexed: 03/18/2023] Open
Abstract
BACKGROUND Transcranial Doppler flow velocity is used to monitor for cerebral vasospasm following aneurysmal subarachnoid hemorrhage. Generally, blood flow velocities appear inversely related to the square of vessel diameter representing local fluid dynamics. However, studies of flow velocity-diameter relationships are few, and may identify vessels for which diameter changes are better correlated with Doppler velocity. We therefore studied a large retrospective cohort with concurrent transcranial Doppler velocities and angiographic vessel diameters. METHODS This is a single-site, retrospective, cohort study of adult patients with aneurysmal subarachnoid hemorrhage, approved by the UT Southwestern Medical Center Institutional Review Board. Study inclusion required transcranial Doppler measurements within </= 24 hours of vessel imaging. Vessels assessed were: bilateral anterior, middle, posterior cerebral arteries; internal carotid siphons; vertebral arteries; and basilar artery. Flow velocity-diameter relationships were constructed and fitted with a simple inverse power function. A greater influence of local fluid dynamics is suggested as power factors approach two. RESULTS 98 patients were included. Velocity-diameter relationships are curvilinear, and well fit by a simple inverse power function. Middle cerebral arteries showed the highest power factors (>1.1, R2>0.9). Furthermore, velocity and diameter changed (P<0.033) consistent with the signature time course of cerebral vasospasm. CONCLUSIONS These results suggest that middle cerebral artery velocity-diameter relationships are most influenced by local fluid dynamics, which supports these vessels as preferred endpoints in Doppler detection of cerebral vasospasm. Other vessels showed less influence of local fluid dynamics, pointing to greater role of factors outside the local vessel segment in determining flow velocity.
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Affiliation(s)
- Richard L Wang
- Department of Anesthesiology and Pain Management; The University of Texas Southwestern, Dallas, Texas, USA; Department of Radiology, University of Miami Miller School of Medicine.
| | - Kevin J Gingrich
- Department of Anesthesiology and Pain Management; The University of Texas Southwestern, Dallas, Texas, USA; Department of Anesthesiology and Pain Management, Univ. of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, Texas 75390 USA.
| | - Awais Vance
- Department of Neurological Surgery; The University of Texas Southwestern, Dallas, Texas, USA; Departments of Radiology; The University of Texas Southwestern, Dallas, Texas, USA; Department of Neurosurgery, Baylor Scott & White Medical Center.
| | - Mark D Johnson
- Department of Neurology; The University of Texas Southwestern, Dallas, Texas, USA; Department of Neurology, Univ. of Texas Southwestern Medical Center.
| | - Babu G Welch
- Department of Neurological Surgery; The University of Texas Southwestern, Dallas, Texas, USA; Departments of Radiology; The University of Texas Southwestern, Dallas, Texas, USA; Departments of Neurological Surgery & Radiology, Univ. of Texas Southwestern Medical Center.
| | - David L McDonagh
- Department of Anesthesiology and Pain Management; The University of Texas Southwestern, Dallas, Texas, USA; Department of Neurological Surgery; The University of Texas Southwestern, Dallas, Texas, USA; Department of Neurology; The University of Texas Southwestern, Dallas, Texas, USA; Departments of Anesthesiology and Pain Management, Neurology, and Neurological Surgery; Univ. of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, Texas 75390 USA.
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9
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Tominaga T. Moyamoya Disease and Flow Velocity. JMA J 2023; 6:25-26. [PMID: 36793529 PMCID: PMC9908412 DOI: 10.31662/jmaj.2022-0191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 01/12/2023] Open
Affiliation(s)
- Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
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Xia Z, Depew DC, Valipour R, MacIsaac HJ, Weidman RP. Impacts of invasive mussels on a large lake: Direct evidence from in situ control-volume experiments. Sci Total Environ 2022; 849:157924. [PMID: 35952866 DOI: 10.1016/j.scitotenv.2022.157924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 07/15/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
Invasive dreissenid mussels have reengineered many freshwater ecosystems in North America and Europe. However, few studies have directly linked their filter feeding activity with ecological effects except in laboratory tests or small-scale field enclosures. We investigated in situ grazing on lake seston by dreissenid mussels (mainly quagga mussel Dreissena rostriformis bugensis) using a 'control volume' approach in the nearshore of eastern Lake Erie in 2016. Flow conditions were measured using an acoustic Doppler current profiler, surrounded by three vertical sampling stations that were arranged in a triangular configuration to collect time-integrated water samples from five different depths. Seston variables, including chlorophyll a, phaeopigment, particulate organic carbon and nitrogen, and particulate phosphorus, along with stoichiometric ratios and water flow over mussel colonies, were considered when estimating grazing rates. We observed suboptimal flow velocity for mussel grazing, i.e., 0.028 m s-1 at 0.1 m above bottom (mab), and resuspension was deemed minimal. Water temperature (mean: 25.1 °C) and an unstratified water column were optimal for grazing. Concentration of seston was low (mean: 0.2 mg L-1 particulate organic carbon) and decreased from surface to lakebed where noticeable depletion was observed. Grazing rates calculated at discrete depths varied substantially among trials, with maximum rates occurring at 0.25 or 0.5 mab. Positive grazing rates were restricted to 0.5 mab and below, defining an effective grazing zone (0.1-0.5 mab) in which the flow velocity, seston concentration, and water depth were consistently and positively correlated with grazing rates of different lake seston variables. Horizontal changes in stoichiometric ratios of seston were strongly associated with grazing rates, revealing higher uptake of particulate phosphorus than nitrogen and carbon. Our study supports the nearshore phosphorus shunt hypothesis, which posits that dreissenid mussels retain phosphorus on the lake bottom and contribute to a wide range of ecological effects on freshwater ecosystems.
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Affiliation(s)
- Zhiqiang Xia
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada.
| | - David C Depew
- Environment & Climate Change Canada, Watershed Hydrology & Ecology Research Division, Burlington, ON L7R 4A6, Canada
| | - Reza Valipour
- Environment & Climate Change Canada, Watershed Hydrology & Ecology Research Division, Burlington, ON L7R 4A6, Canada
| | - Hugh J MacIsaac
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada; School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
| | - R Paul Weidman
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada.
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Yang L, Liu J, Qi X, Cheng X, Ma C, Wang Z. Effects of polysaccharides on the hydrodynamic parameters of sheet erosion on loessial slopes. Environ Sci Pollut Res Int 2022; 29:80705-80715. [PMID: 35727511 DOI: 10.1007/s11356-022-21481-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
The variations in hydrodynamic parameters at different polysaccharides rates and the relationships between sheet erosion modulus and hydrodynamic parameters were analyzed to reveal the hydrodynamic mechanism of sheet erosion on loessial slopes. Artificially simulated rainfall experiments were carried out under three slope gradients (10°, 15°, and 20°), three rainfall intensities (1.0, 1.5, and 2.0 mm·min-1), and four dry-spreading rates of polysaccharides (0, 1, 3, and 5 g·m-2). The results showed that (1) four hydrodynamic parameters (flow velocity, shear stress, stream power, and unit stream power) all increased with both rainfall intensities and slope gradients at four rates of polysaccharides. (2) Polysaccharides could effectively reduce hydrodynamic parameters. In contrast to the bare slope, the average flow velocity, shear stress, stream power, and unit stream power diminished by 27.11~41.18%, 9.53~18.67%, 31.82~50.24%, and 27.11~41.18%, respectively. (3) Polysaccharides could effectively reduce the growth rate of the sheet erosion modulus with hydrodynamic parameters, and there were few differences among the different rates (1, 3, and 5 g·m-2). The increasing rates of the sheet erosion modulus with flow velocity, shear stress, stream power, and unit stream power were 14.0~65.7%, 14.8~33.9%, 7.8~23.7%, and 9.7~29.5%, respectively. (4) At different polysaccharides rates, the relationships between sheet erosion modulus and hydrodynamic parameters were all in logarithmic functions. Moreover, flow velocity (R2 ≥ 0.920) and stream power (R2 ≥ 0.876) were better hydrodynamic parameters than shear stress (R2 ≥ 0.598) or unit stream power (R2 ≥ 0.537). Polysaccharides decreased the hydrodynamic parameters and the response rates of sheet erosion to hydrodynamics.
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Affiliation(s)
- Liting Yang
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Jun'e Liu
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China.
| | - Xiaoqian Qi
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Xike Cheng
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Chunyan Ma
- Yulin University, Shaanxi Key Laboratory of Ecological Restoration in Shaanbei Mining Area, Yulin, 719000, Shaanxi, China
| | - Zhanli Wang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, 712100, Shaanxi, China
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12
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Yang Z, Wei C, Liu D, Lin Q, Huang Y, Wang C, Ji D, Ma J, Yang H. The influence of hydraulic characteristics on algal bloom in three gorges reservoir, China: A combination of cultural experiments and field monitoring. Water Res 2022; 211:118030. [PMID: 35065341 DOI: 10.1016/j.watres.2021.118030] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 12/09/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
It is essential to understand the mechanism of algal bloom and develop effect measures to control the hazard in aquatic environment, such as large reservoirs. In this study, a series of experiments, along with field observation from 2007 to 2016, were carried out to identify the hydrodynamic parameters that drive the algal bloom in the Three Gorges Reservoir (TGR), China, and their threshold values were determined. The results show that algae concentration was markedly diluted with a short retention time, and the threshold value of the retention time to avoid algal bloom was approximately less than 3 days. With strong stratification, the algae concentration was able to approach to the level of algal bloom in 10 days, even when the water temperature is lower than 12 °C. The ratio of mixing depth to euphotic depth (Zm/Ze) had significant negative correlations with both algae concentration and algae specific growth rate (SGR). The field monitoring data indicated that Zm/Ze is an important hydrodynamic parameter which sensitively affects algae growth and concentration. This study made the first attempt to determine Zm/Ze >2.8 to restrain algal bloom in the TGR. Our findings shed light on the influence of critical depth on the algal bloom in the TGR, and the results can serve to control algal bloom in reservoirs through discharge operation.
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Affiliation(s)
- Zhengjian Yang
- Hubei Observation and Research Station of Three Gorges Reservoir Ecosystem, China Three Gorges University, Yichang, 443002, China.
| | - Chenyu Wei
- Hubei Observation and Research Station of Three Gorges Reservoir Ecosystem, China Three Gorges University, Yichang, 443002, China
| | - Defu Liu
- Hubei Observation and Research Station of Three Gorges Reservoir Ecosystem, China Three Gorges University, Yichang, 443002, China; Hubei Key Laboratory of Ecological Restoration of River-lakes and Algal Utilization, Hubei University of Technology, Wuhan, 430068, China.
| | - Qicai Lin
- Shaanxi Provincial Academy of Environmental Sciences, Xi'an, 710061, China
| | - Yuling Huang
- Department of water environment, China Institute of Water Resources and Hydropower Research, Beijing, 10038, China
| | - Congfeng Wang
- Hubei Observation and Research Station of Three Gorges Reservoir Ecosystem, China Three Gorges University, Yichang, 443002, China
| | - Daobin Ji
- Hubei Observation and Research Station of Three Gorges Reservoir Ecosystem, China Three Gorges University, Yichang, 443002, China
| | - Jun Ma
- Hubei Key Laboratory of Ecological Restoration of River-lakes and Algal Utilization, Hubei University of Technology, Wuhan, 430068, China
| | - Hong Yang
- Department of Geography and Environmental Science, University of Reading, Whiteknights, Reading, RG6 5TX, UK.
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Ouchi K, Sakuma T, Higuchi T, Yoshida J, Narui R, Nojiri A, Yamane T, Ojiri H. Computed tomography findings associated with the reduction in left atrial appendage flow velocity in patients with atrial fibrillation. Heart Vessels 2022; 37:1436-1445. [PMID: 35178607 DOI: 10.1007/s00380-022-02041-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/03/2022] [Indexed: 11/04/2022]
Abstract
The reduction in flow velocity within the left atrial appendage (LAAFV) is associated with a high risk of thromboembolic events. There has been few reports using sufficient sample size about the relationship between LAAFV reduction and LAA features on cardiac computed tomography (CT), including LAA volume and filling defects, in patients with atrial fibrillation (AF). We evaluated the predictors of reduced flow velocity within the LAA using the findings of cardiac CT in patients with AF. We retrospectively analysed the cardiac CT findings of the LAA of 440 patients who underwent transoesophageal echocardiography prior to pulmonary vein isolation between 12 February, 2013 and 16 December, 2019 at our institution. We investigated the potential predictors of reduced LAAFV and the difference in LAAFV between the different morphological types of the LAA. The reduced flow velocity within the LAA was significantly correlated with higher CHADS2 scores [P = 0.001; odds ratio (OR), 1.52; 95% confidence interval (CI), 1.18-1.95], early filling defect in the LAA (P = 0.001; OR, 3.36; 95% CI 1.63-6.93), and increased indexed LAA volume (P = 0.036; OR, 1.09; 95% CI 1.01-1.19). The LAA morphological type and AF type were not significant predictors of the LAAFV reduction. Increased LAA volume, early filling defects in the LAA, and higher CHADS2 scores were independent predictors of LAAFV reduction in patients with AF. Our findings suggest that cardiac CT findings might allow non-invasive estimation of reduced LAAFV. These CT-derived parameters may provide additional information for the risk stratification and management of thromboembolic events in patients with AF.
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Affiliation(s)
- Kotaro Ouchi
- Department of Radiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan.
| | - Toru Sakuma
- Department of Radiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Takahiro Higuchi
- Department of Radiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Jun Yoshida
- Department of Cardiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Ryosuke Narui
- Department of Cardiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Ayumi Nojiri
- Department of Laboratory Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Teiichi Yamane
- Department of Cardiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Hiroya Ojiri
- Department of Radiology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
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14
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Badhwar S, Chandran DS, Jaryal AK, Narang R, Patel C, Deepak KK. Brachial Artery "Low-Flow Mediated Constriction" Is Associated with Myocardial Perfusion Defect Severity and Mediated by an Altered Flow Pattern during Occlusion. Pulse (Basel) 2022; 9:99-108. [PMID: 35083176 DOI: 10.1159/000519558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 09/08/2021] [Indexed: 02/05/2023] Open
Abstract
Introduction The relationship between low flow-mediated constriction (LFMC), a new proposed measure of endothelial function, with cardiovascular disease severity and its hypothesized stimulus, that is, low flow, has not been comprehensively evaluated. The study evaluated association between change in brachial artery diameter during constriction with severity of myocardial perfusion defect (PD) and alterations in different components of flow profile. Methods Brachial artery responses to occlusion were assessed in 91 patients and 30 healthy subjects. Change in anterograde and retrograde blood flow velocities (delta anterograde blood flow velocity and retrograde blood flow velocity), anterograde shear rate and retrograde shear rate (delta ASR and RSR, respectively), and oscillatory shear index (delta) during forearm occlusion at 50 mm Hg above systolic pressure, from baseline was calculated. Myocardial perfusion was evaluated in patients using exercise single positron emission computed tomography and % myocardial PD was calculated from summed stress score. Results LFMC emerged as independent predictor of defect severity after correcting for age and gender (p = 0.014). Sixty-seven patients (73.6%) and 15 healthy subjects (50%) showed constriction during occlusion. In stepwise backward regression analysis, RSR contributed 35.5% and ASR contributed 20.1% of the total 63.9% variability in artery diameter during occlusion. Conclusion The results suggest that LFMC is independently associated with myocardial perfusion severity and is "mediated" by an altered flow profile during occlusion.
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Affiliation(s)
- Smriti Badhwar
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | - Dinu S Chandran
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | - Ashok K Jaryal
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | - Rajiv Narang
- Department of Cardiology, All India Institute of Medical Sciences, New Delhi, India
| | - Chetan Patel
- Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Kishore Kumar Deepak
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
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15
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Sakakibara T, Suwa K, Ushio T, Wakayama T, Alley M, Saotome M, Satoh H, Maekawa Y. Intra-Left Ventricular Hemodynamics Assessed with 4D Flow Magnetic Resonance Imaging in Patients with Left Ventricular Thrombus. Int Heart J 2021; 62:1287-1296. [PMID: 34853222 DOI: 10.1536/ihj.20-792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Left ventricular thrombus (LVT) has been identified to be crucial in patients with reduced ejection fraction (EF). Three-dimensional cine phase-contrast magnetic resonance imaging (4D flow MRI) can visualize the intra-LV vortex during diastole and quantify the maximum flow velocity (Vmax) at the apex. In this study, we investigated whether the change in the intra-LV vortex was associated with the presence of LVT in patients with cardiac disease.In total, 36 patients (63.5 ± 11.9 years, 28 men, 12/24 with/without LVT) with diffuse LV dysfunction underwent 4D flow MRI. The relative vortex area using streamline images and Vmax of blood flow toward the apex at the apical left ventricle were evaluated. The correlation between the relative vortex area and Vmax was assessed using Pearson's correlation coefficient. The ability to detect LVT was evaluated using the area under the curve (AUC) of the receiver operating characteristic.The relative vortex area was found to be smaller (27 ± 10% versus 45 ± 11%, P = 0.000026), whereas Vmax at the apical left ventricle was lower (19.1 ± 4.4 cm/second versus 27.4 ± 8.9 cm/second, P = 0.0006) in patients with LVT. Vmax at the apical left ventricle demonstrated significant correlations with the relative vortex area (r = 0.43, P = 0.01) and relative transverse length of the vortex (r = 0.45, P = 0.007). The AUC was 0.91 for the relative vortex area, whereas it was 0.80 for Vmax in the apical left ventricle.A smaller LV vortex and lower flow velocity at the LV apex were associated with LVT in patients with reduced EF.
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Affiliation(s)
- Tomoaki Sakakibara
- Division of Cardiology, Internal Medicine 3, Hamamatsu University School of Medicine
| | - Kenichiro Suwa
- Division of Cardiology, Internal Medicine 3, Hamamatsu University School of Medicine
| | - Takasuke Ushio
- Department of Radiology, Hamamatsu University School of Medicine
| | | | - Marcus Alley
- Division of Radiology, Stanford University School of Medicine, Stanford
| | - Masao Saotome
- Division of Cardiology, Internal Medicine 3, Hamamatsu University School of Medicine
| | - Hiroshi Satoh
- Department of Cardiology, Fujinomiya City General Hospital
| | - Yuichiro Maekawa
- Division of Cardiology, Internal Medicine 3, Hamamatsu University School of Medicine
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16
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Zhu M, Yang N, Li Y, Zhang W, Wang L, Niu L, Wang L, Zhang H. Assessing the effects of cascade dams on river ecological status using multi-species interaction-based index of biotic integrity (Mt-IBI). J Environ Manage 2021; 299:113585. [PMID: 34438311 DOI: 10.1016/j.jenvman.2021.113585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/11/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Cascade dams have exerted significant effects on river ecosystems. To quantitatively assess dam-induced effects on river ecological status, a novel multi-species interaction-based index of biotic integrity (Mt-IBI) was developed. Benthic microbiota was selected as a bio-indicator for its sensitivity to the environmental disturbance. An environmental DNA metabarcoding tool was used to identify microbiota (bacteria, protozoan, and metazoan). The Mt-IBI was applied to assess the ecological status of the Hanjiang River, a representative dam-affected river in China. Fifteen sampling sites along the Hanjiang River were sampled in June 2018. Seven core metrics were screened from a total of 364 candidate metrics to calculate the value of the Mt-IBI. The Mt-IBI of the Hanjiang River ranged from 1.90 to 6.39, with a mean value of 4.02. The mean values of Mt-IBI at the reservoir and riverine side of dams were 2.11 and 3.81, respectively. The downstream reach without dam constructions had the highest mean Mt-IBI (5.79). Thus, the continuity of the river was strongly related to the Mt-IBI. Structural equation models (SEMs) were further established to identify the dominant environmental variables in the dam-affected river. The SEMs indicated that flow velocity (coefficient 0.749) was the most important determinant of ecological status in the Hanjiang River. Water organic matter also played a vital role in determining the ecological status of the Hanjiang River, and exerted the strongest direct effect (P < 0.001, r = 0.712). The reliability of SEMs was verified by building a support vector regression model (R2 = 0.8141). This study can provide new tools for ecological assessment and diagnosis, and provide a new perspective for the management of cascade dams.
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Affiliation(s)
- Mengjie Zhu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Nan Yang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Yi Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Wenlong Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Linqiong Wang
- Key Laboratory of Marine Hazards Forecasting, Ministry of Natural Resources, College of Oceanography, Hohai University, Nanjing, 210098, PR China
| | - Lihua Niu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Longfei Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Huanjun Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
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Hohri Y, Numata S, Itatani K, Kanda K, Yamazaki S, Inoue T, Yaku H. Prediction for future occurrence of type A aortic dissection using computational fluid dynamics. Eur J Cardiothorac Surg 2021; 60:384-391. [PMID: 33619516 DOI: 10.1093/ejcts/ezab094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 12/26/2020] [Accepted: 01/22/2021] [Indexed: 01/16/2023] Open
Abstract
OBJECTIVES The actual underlying mechanisms of acute type A aortic dissection (AAAD) are not well understood. The present study aimed to elucidate the mechanism of AAAD using computational fluid dynamics (CFD) analysis. METHODS We performed CFD analysis using patient-specific computed tomography imaging in 3 healthy control cases and 3 patients with AAAD. From computed tomography images, we made a healthy control model or pre-dissection model for CFD analysis. Pulsatile cardiac flow during one cardiac cycle was simulated, and a three-dimensional flow streamline was visualized to evaluate flow velocity, wall shear stress and oscillatory shear index (OSI). RESULTS In healthy controls, the transvalvular aortic flow was parallel to the ascending aorta. There was no spotty high OSI area at the ascending aorta. In pre-dissection patients, accelerated transvalvular aortic flow was towards the posterolateral ascending aorta. The vortex flow was observed on the side of the lesser curvature in mid-systole and expanded throughout the entire ascending aorta during diastole. Systolic wall shear stress was high due to the accelerated aortic blood flow on the side of the greater curvature of the ascending aorta. On the side of the lesser curvature, high OSI areas were observed around the vortex flow. In all pre-dissection cases, a spotty high OSI area was in close proximity to the actual primary entry site of the future AAAD. CONCLUSIONS The pre-onset high OSI area with vortex flow is closely associated with the future primary entry site. Therefore, we can elucidate the mechanism of AAAD with CFD analysis.
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Affiliation(s)
- Yu Hohri
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Satoshi Numata
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Keiichi Itatani
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Keiichi Kanda
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Sachiko Yamazaki
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Tomoya Inoue
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hitoshi Yaku
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
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18
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Zhong H, Li Y, Liu G, Xu T, Suo Y, Wang Z. Study on covalent coupling process and flow characteristics of antibody on the surface of immunoassay microfluidic chip. Prep Biochem Biotechnol 2021; 52:424-432. [PMID: 34383625 DOI: 10.1080/10826068.2021.1958344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The immune response system of immunoassay microfluidic chips is a dynamic reaction process that continuously sends reactants to the surface of a solid carrier. Signal acquisition results from the heterogeneous immune reactions and reactant transport. Antibody immobilization is the most important part of heterogeneous immune reactions, and reactant transport is reflected in the form of fluid velocity. Here, we reported several surface modification processes on polystyrene substrates that are employed to study the relationship between the antibody immobilization and flow behavior in heterogeneous immune response processes. The antibody was immobilized using covalent grafting. Based on the mechanism of sandwich enzyme linked immunosorbent assay, a fluorescence quantitative detection method was used to evaluate the immune response process. The effects of different surface modification processes on immune response and flow behavior were studied. We identified an optimal flow velocity in the dynamic immune response system in the microfluidic chip. The immune response signal was the strongest when the average flow velocity was approximately 0.2 mm/s in the procalcitonin detection system. Compared with the amino and aldehyde group substrates, the epoxy group substrate has the highest antibody immobilization efficiency; compared with the surface modified by small molecular groups, the introduction of Poly-L-Lysine can increase the amount of antibody immobilization.
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Affiliation(s)
- Hao Zhong
- Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control, Tsinghua University, Beijing, China.,AVIC Jincheng Nanjing Engineering Institute of Aircraft System, Nanjing, China
| | - Yong Li
- Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control, Tsinghua University, Beijing, China.,Tianjin Research Institute for Advanced Equipment, Tsinghua University, Tianjin, China
| | - Guodong Liu
- Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control, Tsinghua University, Beijing, China
| | - Tao Xu
- Tianjin Research Institute for Advanced Equipment, Tsinghua University, Tianjin, China
| | - Yiping Suo
- Tianjin Research Institute for Advanced Equipment, Tsinghua University, Tianjin, China
| | - Zhiqiang Wang
- Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control, Tsinghua University, Beijing, China.,Tianjin Research Institute for Advanced Equipment, Tsinghua University, Tianjin, China
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19
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Medici G, West LJ. Groundwater flow velocities in karst aquifers; importance of spatial observation scale and hydraulic testing for contaminant transport prediction. Environ Sci Pollut Res Int 2021; 28:43050-43063. [PMID: 34125385 DOI: 10.1007/s11356-021-14840-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 06/07/2021] [Indexed: 06/12/2023]
Abstract
We review scale dependence of hydraulic conductivities and effective porosities for prediction of contaminant transport in four UK karst aquifers. Approaches for obtaining hydraulic parameters include core plug, slug, pumping and pulse tests, calibration of groundwater flow models and spring recession curves. Core plug and slug tests are unsuitable because they do not characterize a large enough volume to include a representative fracture network. Pumping test values match regional-scale hydraulic conductivities from flow modelling for the less intensively karstified aquifers: Magnesian Limestone, Jurassic Limestone and Cretaceous Chalks. Reliable bulk hydraulic conductivities were not available for the intensively karstified Carboniferous Limestone due to dominance of flow through pipe conduits in Mendips. Here, the only hydraulic conductivity value found from spring recession is one order of magnitude higher than that indicated by pumping tests. For all four carbonate aquifers, effective porosities assumed for transport modelling are two orders of magnitude higher than those found from tracer and hydrogeophysical tests. Thus, a combination of low hydraulic conductivities and assumed flowing porosities resulted in underestimated flow velocities. The UK karst aquifers are characterized by a range of hydraulic behaviours that fit those of karst aquifers worldwide. Indeed, underestimation of flow velocity due to inappropriate parameter selection is common to intensively karstified aquifers of southern France, north-western Germany and Italy. Similar issues arise for the Canadian Silurian carbonates where the use of high effective porosities (e.g. 5%) in transport models leads to underestimation of groundwater velocities. We recommend values in the range of 0.01-1% for such aquifers.
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Affiliation(s)
- Giacomo Medici
- G360 Institute of Groundwater Research, University of Guelph, Stone Road, Guelph, Ontario, N1G 2W1, Canada.
| | - Landis Jared West
- School of Earth and Environment, University of Leeds, Woodhouse Lane, Leeds, W Yorkshire, LS2 9JT, UK
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de Vries HJ, Kleibusch E, Hermes GDA, van den Brink P, Plugge CM. Biofouling control: the impact of biofilm dispersal and membrane flushing. Water Res 2021; 198:117163. [PMID: 33951583 DOI: 10.1016/j.watres.2021.117163] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 05/26/2023]
Abstract
Pure culture studies have shown that biofilm dispersal can be triggered if the nutrient supply is discontinued by stopping the flow. Stimulating biofilm dispersal in this manner would provide a sustainable manner to control unwanted biofilm growth in industrial settings, for instance on synthetic membranes used to purify water. The response of multispecies biofilms to nutrient limitation has not been thoroughly studied. To assess biomass dispersal during nutrient limitation it is common practise to flush the biofilm after a stop-period. Hence, flow-stop-induced biomass removal could occur as a response to nutrient limitation followed by mechanical removal due to biofilm flushing (e.g. biofilm detachment). Here, we investigated the feasibility to reduce membrane biofouling by stopping the flow and flushing the membrane. Using a membrane fouling simulator, biomass removal from synthetic membranes after different stop-periods was determined, as well as biomass removal at different cross flow velocities. Biomass removal from membrane surfaces depended on the nutrient limiting period and on the flow velocity during the biofilm flush. When flushed at a low flow velocity (0.1 m.s-1), the duration of the stop-period had a large effect on the biomass removal rate, but when the flow velocity was increased to 0.2 m.s-1, the length of the stop period became less considerable. The flow velocity during membrane flushing has an effect on the bacterial community that colonized the membranes afterwards. Repetition of the stop-period and biofilm flushing after three repetitive biofouling cycles led to a stable bacterial community. The increase in bacterial community stability coincided with a decrease in cleaning effectivity to restore membrane performance. This shows that membrane cleaning comes at the costs of a more stable bacterial community that is increasingly difficult to remove.
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Affiliation(s)
- Hendrik J de Vries
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands; Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlands
| | - Eva Kleibusch
- Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlands
| | - Gerben D A Hermes
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Paula van den Brink
- Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlands
| | - Caroline M Plugge
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands; Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlands.
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21
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Czigler A, Fedriga M, Beqiri E, Lalou AD, Calviello LA, Cabeleira M, Toth P, Smielewski P, Czosnyka M. Errors and Consequences of Inaccurate Estimation of Mean Blood Flow Velocity in Cerebral Arteries. Acta Neurochir Suppl 2021; 131:23-5. [PMID: 33839811 DOI: 10.1007/978-3-030-59436-7_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Many transcranial Doppler ultrasonography devices estimate the mean flow velocity (FVm) by using the traditional formula (FVsystolic + 2 × FVdiastolic)/3 instead of a more accurate formula calculating it as the time integral of the current flow velocities divided by the integration period. We retrospectively analyzed flow velocity and intracranial pressure signals containing plateau waves (transient intracranial hypertension), which were collected from 14 patients with a traumatic brain injury. The differences in FVm and its derivative pulsatility index (PI) calculated with the two different methods were determined. We found that during plateau waves, when the intracranial pressure (ICP) rose, the error in FVm and PI increased significantly from the baseline to the plateau (from 4.6 ± 2.4 to 9.8 ± 4.9 cm/s, P < 0.05). Similarly, the error in PI also increased during plateau waves (from 0.11 ± 0.07 to 0.44 ± 0.24, P < 0.005). These effects were most likely due to changes in the pulse waveform during increased ICP, which alter the relationship between systolic, diastolic, and mean flow velocities. If a change in the mean ICP is expected, then calculation of FVm with the traditional formula is not recommended.
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Fujii K, Yoshida N, Miyazaki K. Michaelis-Menten equation considering flow velocity reveals how microbial fuel cell fluid design affects electricity recovery from sewage wastewater. Bioelectrochemistry 2021; 140:107821. [PMID: 33915342 DOI: 10.1016/j.bioelechem.2021.107821] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/24/2021] [Accepted: 04/07/2021] [Indexed: 10/21/2022]
Abstract
Hydrodynamics has received considerable attention for application in improving microbial fuel cell (MFC) performance. In this study, a method is proposed to calculate the effect of fluid flow on MFC current production from sewage wastewater. First, the effect of flow velocity in an up-flow channel was evaluated, where an air-core MFC was polarized with external resistance (Rext). When tested at a flow velocity ranging from 0 to 20 cm s-1, the MFC with the higher flow velocity produced more current. In sewage wastewater with a chemical oxygen demand (COD) of 76 mg L-1, the MFC polarized with 3 Ω of Rext, and a flow velocity of 20 cm s-1 had 5.4 times more current than the MFC operating in a no-flow environment. This magnitude decreased with higher Rext and COD values. The Michaelis-Menten equation, modified herein by integrating COD and flow velocity, demonstrated the production of current by MFC operating under different conditions of flow. Calculation of current by MFC in a virtual fluid suggested that the flow surrounding the MFC varied with the configuration and affected the current production.
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Affiliation(s)
- Ken Fujii
- Department of Architecture, Civil Engineering and Industrial Management Engineering, Nagoya Institute of Technology (Nitech), Nagoya, Japan
| | - Naoko Yoshida
- Department of Architecture, Civil Engineering and Industrial Management Engineering, Nagoya Institute of Technology (Nitech), Nagoya, Japan.
| | - Kohei Miyazaki
- Department of Architecture, Civil Engineering and Industrial Management Engineering, Nagoya Institute of Technology (Nitech), Nagoya, Japan
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Xia Z, MacIsaac HJ, Hecky RE, Depew DC, Haffner GD, Weidman RP. Multiple factors regulate filtration by invasive mussels: Implications for whole-lake ecosystems. Sci Total Environ 2021; 765:144435. [PMID: 33418329 DOI: 10.1016/j.scitotenv.2020.144435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 06/12/2023]
Abstract
The quagga mussel (Dreissena rostriformis bugensis) is a filter-feeding invasive species that has re-engineered many freshwater ecosystems worldwide. High clearance rates (CRs) and dense populations underpin their ecological impacts. CRs, however, are highly variable, as are environmental factors that regulate them. Despite their widespread distribution in Europe and North America, knowledge of how multiple environmental factors regulate CRs of quagga mussels remains limited. We investigated quagga mussel CRs under varying conditions including water temperature, food availability, habitat depth, flow velocity, and duration of incubation in chambers with both static and flowing water. We found that CR was positively related to water temperature and initial food concentration in static chambers. When coupled with limited food concentration, cold water (7.5 °C), due to a deep-water upwelling event, produced very low CR (~ 10× lower) compared to warmer water (12-24 °C) (0.47 vs. 3.12-5.84 L g-1 DW h-1). Mussels from deeper water (20 m) had CRs that were ~ 3.5× higher than from shallower depths (2-10 m) and CRs were inversely affected by total mussel dry weight. Flow rates from 1 to 22 cm s-1 generated a unimodal pattern of CR with an optimal flow velocity of 6-12 cm s-1 (~ 2× higher than suboptimal CRs). Enhanced flow velocity (22 cm s-1), reflective of storm conditions in shallow waters, significantly increased the closing/reopening activity of mussel valves relative to lower velocities (1-12 cm s-1). Incubation time had a strong negative effect (~ 2-4× reduction) on CRs likely reflecting refiltration in static chambers versus food saturation of mussels in flowing chambers, respectively. Our findings highlight how multiple factors can influence quagga mussel CRs by factors of 2-10. Given widespread habitat heterogeneity in large aquatic ecosystems, whole-lake estimates of mussel impacts should include multiple regulatory factors that affect mussel filtration.
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Affiliation(s)
- Zhiqiang Xia
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada.
| | - Hugh J MacIsaac
- School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China; Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada.
| | - Robert E Hecky
- Large Lakes Observatory, University of Minnesota-Duluth, Duluth, MN 55812, USA.
| | - David C Depew
- Environment & Climate Change Canada, Watershed Hydrology & Ecology Research Division, Burlington, ON L7R 4A6, Canada.
| | - G Douglas Haffner
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada.
| | - R Paul Weidman
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada.
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Xia G, Wang J, Liu Z, Bai L, Ma L. Effect of sample volume on the sensitivity of lateral flow assays through computational modeling. Anal Biochem 2021; 619:114130. [PMID: 33600781 DOI: 10.1016/j.ab.2021.114130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 01/17/2021] [Accepted: 02/03/2021] [Indexed: 12/13/2022]
Abstract
Lateral flow assays (LFAs) are extensively used in qualitative detection because of their convenience, low cost, fast results, and ease of operation. However, the sample volume used in a lateral flow assay is usually determined experimentally. We test and find that the flow velocity is influenced by sample volume, using fluorescent microspheres as label particles, when analyte concentration is fixed in a sandwich LFA. A model is developed based on mass-action kinetics and advection-diffusion-reaction equation, combing the conjugate pad and nitrocellulose membrane. The model shows predictions from 10 to 120 μL, and predicts accurately the experimental results from 50 to 120 μL where the fluid can flow to the test line. Over all, the model can provide predictions over a wide range of sample volumes for sensitivity analysis. On the basis of the model, the sensitivity of the LFA can be improved according to the sample volume added in the experiment.
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Affiliation(s)
- Guo Xia
- Academy of Opto-electric Technology, Hefei University of Technology, Special Display and Imaging Technology Innovation Center of Anhui Province, State Key Laboratory of Advanced Display Technology, 193 Tunxi Road, Hefei, 230009, China.
| | - Jiangtao Wang
- Academy of Opto-electric Technology, Hefei University of Technology, Special Display and Imaging Technology Innovation Center of Anhui Province, State Key Laboratory of Advanced Display Technology, 193 Tunxi Road, Hefei, 230009, China
| | - Zhijian Liu
- School of Instrument Science and Opto-electronic Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, 230009, China
| | - Lihao Bai
- Academy of Opto-electric Technology, Hefei University of Technology, Special Display and Imaging Technology Innovation Center of Anhui Province, State Key Laboratory of Advanced Display Technology, 193 Tunxi Road, Hefei, 230009, China
| | - Long Ma
- Academy of Opto-electric Technology, Hefei University of Technology, Special Display and Imaging Technology Innovation Center of Anhui Province, State Key Laboratory of Advanced Display Technology, 193 Tunxi Road, Hefei, 230009, China
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Waringer J, Vitecek S, Martini J, Zittra C, Handschuh S, Vieira A, Kuhlmann HC. Hydraulic niche utilization by larvae of the three Drusinae clades (Insecta: Trichoptera). Biologia (Bratisl) 2021; 76:1465-73. [PMID: 33854256 DOI: 10.2478/s11756-020-00648-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydraulic niche descriptors of final instar larvae of nine Drusus species (Trichoptera) were studied in small, spring-fed, first-order headwaters located in the Mühlviertel (Upper Austria), Koralpe (Carinthia, Austria), and in the Austrian and Italian Alps. The species investigated covered all three clades of Drusinae: the shredder clade (Drusus franzi, D. alpinus), the grazer clade (D. biguttatus, D. chauvinianus, D. dudor, D. monticola), and the filtering carnivore clade (D. chrysotus, D. katagelastos, D. muelleri). Flow velocity was measured at front center of 68 larvae, head upstream, on the top of mineral substrate particles at water depths of 10–30 mm, using a tripod-stabilized Micro propeller meter (propeller diameter = 10 mm). Each data series consisted of a sampled measurement lasting 30 s (measuring interval = 1 s). In total, 2040 single velocity measurements were taken. Instantaneous flow velocities and drag at the sites of the 68 larvae varied from 0 to 0.93 m s−1 and 0 to 8346 *10−6 N, respectively. Flow velocities and drag between the three clades were highly significantly different (p < 0.001); mean velocity (+ 95% confidence limits) for the three clades were 0.09 + 0.00 m s−1 for the shredder, 0.25 + 0.00 m s−1 for the grazer, and 0.31 + 0.01 m s−1 for the filtering carnivore clade; the corresponding data for drag were (85 + 18)*10−6 N, (422 + 61)*10−6 N and (1125 + 83)*10−6 N, respectively. Adhesive friction ranged from (41.07 + 53.03)*10−6 N in D. franzi to (255.24 + 216.87)*10−6 N in D. chrysotus. Except in D. franzi and D. dudor adhesive friction was always well below drag force, indicating that submerged weight alone was not sufficient to stabilize the larvae in their hydraulic environment. Reynolds numbers varied between 0 in D. franzi and D. alpinus, and 12,634 in D. katagelastos, with 7% of the total in the laminar (R < 500), 30% in the transitional (R = 500–2000), and 61% in the fully turbulent stage (R > 2000). Froude numbers (Fr) varied from 0 to 2.97. The two Drusus species of the shredder clade and three out of four species of the grazer clade were exposed to subcritical Fr < 1, one species of the grazer clade and two out of three species of the filtering clade to supercritical Froude numbers >1.
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26
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Klang JM, Wouatidem-Nanfack SL, Tene ST, Boungo GT, Womeni HM. Optimisation of the production of corn amylase flour from corn Atp and Kassaï varieties for the fluidification and energy density increase of cassava gruel. Heliyon 2020; 6:e05344. [PMID: 33150214 PMCID: PMC7599129 DOI: 10.1016/j.heliyon.2020.e05344] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 07/01/2020] [Accepted: 10/22/2020] [Indexed: 11/29/2022] Open
Abstract
The energy density of the complementary gruels can be increased by the use of sprouted flours. This led us to determine the conditions for obtaining and using sprouted corn flour for optimal fluidification of fermented cassava flour gruels. To do this, the germinated corn flour (GCF) varieties Atp and Kassaï was produced according to the response surface methodology and the Doehlert plan was used with factors such as soaking (12-48 h) and germination (24-96 h) times. Once obtained, these GCF were used to increase the energy density of cassava flour gruels with flow velocity as response. The Doehlert plan was also used with fermented cassava flour concentration (17.5-30 %) and optimised sprouted corn flour mass (1-5 g) as factors. The experimental design that had been performed indicated that the effectiveness of corn amylase flour to fluidify the gruels depends not only to the conditions of production (soaking and germination) (p < 0.05) but also their incorporation during the preparation (corn amylase-fermented cassava flour) (p < 0.05). The rich corn amylase flour can be obtained by soaking Kassaï and Atp varieties for 20 h and 28 h respectively and germinated for 90.82 h. Application of these GCF during the preparation of fermented cassava flour gruels has shown that to obtain gruels with flow velocities between 100-160 mm/30s, it was necessary to couple 1.16 g of sprouted corn flour variety Kassaï for 26.23 % of fermented cassava flour and 1.12 g of corn flour variety Atp for 25.94 % of fermented cassava flour. The use of these couples has made it possible to multiply the energy density of the gruels by 6.55 and 6.49, respectively. In view of these results, it is therefore advisable to use the germinated corn flours produced under the conditions obtained to fluidise and increase the energy density of the fermented cassava gruels.
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Affiliation(s)
- Julie Mathilde Klang
- Research Unit of Biochemistry, Medicinal Plants, Food Science and Nutrition, Department of Biochemistry, Faculty of Science, University of Dschang, P.O BOX 67, Dschang, Cameroon
| | - Sylvanie-Linda Wouatidem-Nanfack
- Research Unit of Biochemistry, Medicinal Plants, Food Science and Nutrition, Department of Biochemistry, Faculty of Science, University of Dschang, P.O BOX 67, Dschang, Cameroon
| | - Stephano Tambo Tene
- Research Unit of Biochemistry, Medicinal Plants, Food Science and Nutrition, Department of Biochemistry, Faculty of Science, University of Dschang, P.O BOX 67, Dschang, Cameroon
| | - Gires Teboukeu Boungo
- Research Unit of Biochemistry, Medicinal Plants, Food Science and Nutrition, Department of Biochemistry, Faculty of Science, University of Dschang, P.O BOX 67, Dschang, Cameroon
| | - Hilaire Macaire Womeni
- Research Unit of Biochemistry, Medicinal Plants, Food Science and Nutrition, Department of Biochemistry, Faculty of Science, University of Dschang, P.O BOX 67, Dschang, Cameroon
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Caroppi G, Västilä K, Gualtieri P, Järvelä J, Giugni M, Rowiński PM. Acoustic Doppler velocimetry (ADV) data on flow-vegetation interaction with natural-like and rigid model plants in hydraulic flumes. Data Brief 2020; 32:106080. [PMID: 32793778 PMCID: PMC7415830 DOI: 10.1016/j.dib.2020.106080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 12/02/2022] Open
Abstract
Vegetation, generally present along river margins and floodplains, governs key hydrodynamic processes in riverine systems. Despite the flow-influencing mechanisms exhibited by natural vegetation and driven by its complex morphology and flexibility, vegetation has been conventionally simulated by using rigid cylinders. This article presents a dataset obtained from hydraulic experiments performed for investigating the flow-vegetation interaction in partly vegetated channels. Vegetation was simulated by using both natural-like and rigid model plants. Specifically, two sets of experiments are described: in the first, vegetation was simulated with natural-like flexible foliated plants standing on a grassy bed; in the second, rigid cylinders were used. Experiments with rigid cylinders were designed to be compared against tests with natural-like plants, as to explore the effects of vegetation representation. The following experimental data were produced: 3D instantaneous velocity measured by acoustic Doppler velocimetry, vegetation motion video recordings, and auxiliary data including detailed vegetation characterization. These experiments are unique both for the use of natural-like flexible woody vegetation in hydraulic experiments and for the similarity achieved between the resulting observed vegetated shear layers. These data are expected to be useful in vegetated flows model development and validation, and represent a unique benchmark for the interpretation of the flow-vegetation interaction in partly vegetated channels.
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Affiliation(s)
- Gerardo Caroppi
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Naples, Italy
- Department of Built Environment, Aalto University School of Engineering, Espoo, Finland
| | - Kaisa Västilä
- Department of Built Environment, Aalto University School of Engineering, Espoo, Finland
- Freshwater Centre, Finnish Environment Institute, Helsinki, Finland
| | - Paola Gualtieri
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Naples, Italy
| | - Juha Järvelä
- Department of Built Environment, Aalto University School of Engineering, Espoo, Finland
| | - Maurizio Giugni
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Naples, Italy
| | - Paweł M Rowiński
- Institute of Geophysics, Polish Academy of Sciences, Warsaw, Poland
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Juntunen J, Ahkola H, Krogerus K, Huttula T. New theory of time integrative passive samplers. Anal Chim Acta 2020; 1127:269-281. [PMID: 32800132 DOI: 10.1016/j.aca.2020.05.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/14/2020] [Accepted: 05/17/2020] [Indexed: 11/19/2022]
Abstract
Current theoretical, two compartment description of integrative passive sampling is renewed to establish a three-compartment model. The developed theoretical description includes external chemical conditions near the receiving phase, conditions inside the receiving phase and the chemically bonded compartments. New variable p, which controls the chemical bonding process into the sampler receiving phase is introduced. This new theoretical model enables derivation of equations for accumulation of masses in situations where convective mass transfer coefficient (h) and chemically bonding activity (p) are defined as a piece-wise constant functions of time. Previous two compartment model, which connects time average external concentration and accumulated mass is derived directly to the case where h and p are constants during the whole observation period. For other situations more complex equation is derived. Applicability of new equations are tested in laboratory experiments with fluctuating external chemical concentration.
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Affiliation(s)
- Janne Juntunen
- Finnish Environment Institute (SYKE), Survontie 9 A, 40500, Jyväskylä, Finland.
| | - Heidi Ahkola
- Finnish Environment Institute (SYKE), Survontie 9 A, 40500, Jyväskylä, Finland
| | - Kirsti Krogerus
- Finnish Environment Institute (SYKE), Survontie 9 A, 40500, Jyväskylä, Finland
| | - Timo Huttula
- Finnish Environment Institute (SYKE), Survontie 9 A, 40500, Jyväskylä, Finland
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Wen C, Broholm MM, Dong J, Uthuppu B, Jakobsen MH, Fjordbøge AS. Transport of citrate and polymer coated gold nanoparticles (AuNPs) in porous media: Effect of surface property and Darcy velocity. J Environ Sci (China) 2020; 92:235-244. [PMID: 32430126 DOI: 10.1016/j.jes.2020.02.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/21/2020] [Accepted: 02/23/2020] [Indexed: 06/11/2023]
Abstract
With the release of nanoparticles (NPs) into the subsurface, it is imperative to better understand the fate and transport of NPs in porous media. Three types of stable AuNPs were used as model NPs to investigate the impact of surface coatings (type and coverage) and water velocity on the NP transport in a porous media (column studies). The NPs were electrostatic stabilized citrate AuNPs and sterically stabilized AuNPs with amphiphilic block co-polymer (PVA-COOH) in two particle/polymer ratios (weak vs. strong stabilization). The citrate AuNPs transport was sensitive to ionic changes in the mixing front of the plume, where destabilization occurred, and will therefore depend on the size/type of release. Blocking of deposition sites by aggregates was seen to facilitate transport, whereby a higher flow velocity (larger shadow zone) also resulted in better transport. The polymeric surface coating had great impact with steric repulsion as a main force contributing to the transport of NPs in the porous media. Sufficient polymer coating was crucial to obtain highly unfavorable attachment conditions (very low α) where the enhanced NP mobility was independent of the water velocity (comparable to solute tracer). Without sufficient steric stabilization, the transport and recovery was significantly reduced compared to the solute tracer, but increased with increasing water velocity. This highlights the importance of sufficient surface coating to achieve enhanced mobility, but also the increased risk of spreading to down-gradient receptors. For the (weakly) sterically stabilized NPs, the loss of polymer through ligand exchange with the porous media negates transport.
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Affiliation(s)
- Chunyu Wen
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark; Key Lab of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun 130021. China
| | - Mette M Broholm
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark
| | - Jun Dong
- Key Lab of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun 130021. China
| | - Basil Uthuppu
- Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark
| | - Mogens Havsteen Jakobsen
- Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark
| | - Annika S Fjordbøge
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark.
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Guibal R, Lissalde S, Guibaud G. Experimental Estimation of 44 Pharmaceutical Polar Organic Chemical Integrative Sampler Sampling Rates in an Artificial River under Various Flow Conditions. Environ Toxicol Chem 2020; 39:1186-1195. [PMID: 32222997 DOI: 10.1002/etc.4717] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 12/12/2019] [Accepted: 03/19/2020] [Indexed: 05/27/2023]
Abstract
The present study pertains to a polar organic chemical integrative sampler (POCIS) laboratory calibration to estimate the sampling rates for 44 pharmaceuticals featuring a wide range of polarity (-0.6 < octanol/water partition coefficient [log KOW ] < 5.4). The calibration was performed at 16.0 ± 1.5 °C for 4 water flow velocities (0, 2-3, 6-7, and 20 cm/s) in both a tank (for calibration at 0 cm/s) and a laboratory-scale artificial river filled with 200 and 500 L of tap water spiked with 0.3 µg/L of each compound, respectively. Twelve new sampling rates and 26 sampling rates already available in the literature were determined, whereas the sampling rates for 6 pharmaceuticals could not be determined due to nonlinearity or poor accumulation in POCIS. An increase in the sampling rate value with flow velocity was observed, which is consistent with a decrease in the effective thickness of the water boundary layer at the POCIS membrane surface. Environ Toxicol Chem 2020;39:1186-1195. © 2020 SETAC.
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Affiliation(s)
- R Guibal
- Laboratoire Peirene EA7500, University of Limoges, Unité de Recherche Associée Institut National de Recherche en Sciences et Technologies, Ecole Nationale Supérieure d'Ingénieurs de Limoges-Ecole Nationale Supérieure de Céramique Industrielle, Limoges, France
| | - S Lissalde
- Laboratoire Peirene EA7500, University of Limoges, Unité de Recherche Associée Institut National de Recherche en Sciences et Technologies, Limoges, France
| | - G Guibaud
- Laboratoire Peirene EA7500, University of Limoges, Unité de Recherche Associée Institut National de Recherche en Sciences et Technologies, Limoges, France
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Nakamizo A, Amano T, Matsuo S, Kuwashiro T, Yasaka M, Okada Y. Common carotid flow velocity is associated with cognitive function after carotid endarterectomy. J Clin Neurosci 2020; 76:53-57. [PMID: 32307301 DOI: 10.1016/j.jocn.2020.04.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/09/2020] [Indexed: 11/24/2022]
Abstract
The relationship between ultrasonographic flow parameters and cognitive function has not been well studied. This study aimed to clarify associations between carotid flow velocity (FV) and cognitive function in patients with a history of carotid endarterectomy (CEA). Ninety-four patients who previously underwent CEA participated in this study. The Neurobehavioral Cognitive Status Examination (Cognistat) and Frontal Assessment Battery (FAB) were adopted to assess cognitive functions at a mean of 6.5 ± 3.2 years after CEA. End-diastolic flow velocity (EDV) of the left and right common carotid artery (CCA) was significantly associated with total Cognistat score (p < 0.001) and total FAB score (p < 0.05). Pulsatility index (PI) of the left CCA was significantly associated with total Cognistat score and total FAB score (p < 0.01). A cut-off right CCA EDV of 14.5 cm/s offered the most reliable predictor of the bottom 25th percentile of total Cognistat score (sensitivity 83.3%, specificity 61.0%, area under the curve (AUC) 0.731, p = 0.0060), while a cut-off left CCA PI of 1.83 was the most reliable predictor of the bottom 25th percentile of total FAB score (sensitivity 73.3%, specificity 60.0%, AUC 0.679, p = 0.0179). Left and right CCA EDV correlated with sub-components of comprehension, construction, judgment, programming (p < 0.01), and conceptualization (p < 0.05). Right CCA EDV correlated with similarity (p < 0.01), repetition, naming, and memory (p < 0.05). Left CCA PI correlated with attention, conceptualization (p < 0.01), repetition, construction, similarity, and mental flexibility (p < 0.05), while right CCA PI correlated with construction (p < 0.05). CCA FV may offer useful markers of cognitive functions in patients with a history of CEA.
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Affiliation(s)
- Akira Nakamizo
- Departments of Neurosurgery, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, 1-8-1, Jigyo-hama, Chuo-ku, Fukuoka 810-8563, Japan.
| | - Toshiyuki Amano
- Departments of Neurosurgery, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, 1-8-1, Jigyo-hama, Chuo-ku, Fukuoka 810-8563, Japan
| | - Satoshi Matsuo
- Departments of Neurosurgery, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, 1-8-1, Jigyo-hama, Chuo-ku, Fukuoka 810-8563, Japan
| | - Takahiro Kuwashiro
- Departments of Cerebrovascular Medicine and Neurology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, 1-8-1, Jigyo-hama, Chuo-ku, Fukuoka 810-8563, Japan
| | - Masahiro Yasaka
- Departments of Cerebrovascular Medicine and Neurology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, 1-8-1, Jigyo-hama, Chuo-ku, Fukuoka 810-8563, Japan
| | - Yasushi Okada
- Departments of Cerebrovascular Medicine and Neurology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, 1-8-1, Jigyo-hama, Chuo-ku, Fukuoka 810-8563, Japan
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Ćmiel AM, Strużyński A, Wyrębek M, Lipińska AM, Zając K, Zając T. Response of freshwater mussel recruitment to hydrological changes in a eutrophic floodplain lake. Sci Total Environ 2020; 703:135467. [PMID: 31759716 DOI: 10.1016/j.scitotenv.2019.135467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 10/16/2019] [Accepted: 11/08/2019] [Indexed: 06/10/2023]
Abstract
Although eutrophication of freshwaters is a natural process, the human impact often leads to inland waters becoming overloaded with nutrients, impoverishing many valuable and vanishing habitats, such as floodplain lakes. These changes need to be reversed if the occurrence of endangered aquatic species is to be restored. In this paper we analyse the impact of a change in the water regime of a naturally eutrophic floodplain lake, which harbours a large diversity of Unionidae (large freshwater mussels), a globally threatened taxonomic group that provides important ecosystem functions and services. We found that a slight increase in the discharge from this waterbody, following the construction of an additional outflow pipe, positively influenced recruitment in three of the five mussel species inhabiting the lake. We also found that, after the construction of this additional outflow, the niches of juveniles of Anodonta cygnea and Unio spp. changed, revealing differences in their hydrological requirements. Our results suggest that, as in lotic habitats, complex hydraulic parameters are highly significant to unionid mussels in lentic conditions.
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Affiliation(s)
- Adam M Ćmiel
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120 Kraków, Poland.
| | - Andrzej Strużyński
- Kraków University of Agriculture, Faculty of Environmental Engineering and Land Surveying, Mickiewicza 24/28, 30-059 Kraków, Poland
| | - Maciej Wyrębek
- Kraków University of Agriculture, Faculty of Environmental Engineering and Land Surveying, Mickiewicza 24/28, 30-059 Kraków, Poland
| | - Anna M Lipińska
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120 Kraków, Poland
| | - Katarzyna Zając
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120 Kraków, Poland
| | - Tadeusz Zając
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120 Kraków, Poland
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Affiliation(s)
- Chiara Robba
- Policlinico San Martino, IRCCS per l'Oncologia e Neuroscienze, Dipartimento di Scienze Chirurgiche e Diagnostiche Integrate, Università degli Studi di Genova, Genova, Italy
| | - Fabio Silvio Taccone
- Department of Intensive Care Medicine, Erasme Hospital, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Brussels, Belgium.
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Salis RK, Bruder A, Piggott JJ, Summerfield TC, Matthaei CD. Multiple-stressor effects of dicyandiamide (DCD) and agricultural stressors on trait-based responses of stream benthic algal communities. Sci Total Environ 2019; 693:133305. [PMID: 31635001 DOI: 10.1016/j.scitotenv.2019.07.111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 06/10/2023]
Abstract
Agricultural practices often result in multiple stressors affecting stream ecosystems, and interacting stressors complicate environmental assessment and management of impacted streams. The nitrification inhibitor dicyandiamide (DCD) is used for nitrogen management on farmland. Effects of leached DCD on stream ecosystems are still largely unstudied, even though it could be relevant as a stressor on its own or in combination with other agricultural stressors. We conducted two experiments in 128 outdoor stream-fed mesocosms to assess stressor effects on biomass, cell density, taxon richness, evenness and functional trait composition of benthic algal communities. First, we examined responses to a wide DCD gradient (eight concentrations, 0-31 mg L-1) and two additional stressors, deposited fine sediment (none, high) and nutrient enrichment (ambient, enriched). Second, we determined algal responses to four stressors: DCD, sediment, nutrients, and reduced flow velocity. Here DCD treatments included controls, constant application (1.4 mg L-1) and two pulsed treatments mimicking concentration patterns in real streams (peaks 3.5 mg L-1, 2.2 mg L-1). Sediment and nutrient enrichment were influential stressors in both experiments, with fine sediment having the most pervasive effects. In Experiment 2, reduced flow velocity had pervasive effects and stressor interactions were mainly restricted to two-way interactions. DCD had few, weak stressor main effects, especially at field-realistic concentrations (Experiment 2). At the highest concentrations in Experiment 1 (above levels observed in real streams), DCD effects were still rare but some significant stressor interactions occurred. Analyses of functional traits were helpful in identifying potential mechanisms driving changes in densities and community composition. These findings suggest that, while DCD on its own may be a minor stressor, it could have adverse effects on algal communities already exposed to other stressors, a scenario common in agricultural streams.
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Affiliation(s)
- Romana K Salis
- Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand; Aquatic Ecosystem Research, Faculty of Biology, University of Duisburg-Essen, Universitätsstraße 5, 45141 Essen, Germany.
| | - Andreas Bruder
- Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand; Laboratory of Applied Microbiology, University of Applied Sciences and Arts of Southern Switzerland, Via Mirasole 22A, 6500 Bellinzona, Switzerland
| | - Jeremy J Piggott
- Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand; Trinity Centre for the Environment & Department of Zoology, School of Natural Sciences, Trinity College Dublin, The University of Dublin, College Green, Dublin 2, Ireland
| | - Tina C Summerfield
- Department of Botany, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Christoph D Matthaei
- Department of Zoology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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Calapez AR, Elias CL, Almeida SFP, Brito AG, Feio MJ. Sewage contamination under water scarcity effects on stream biota: biofilm, grazers, and their interaction. Environ Sci Pollut Res Int 2019; 26:26636-26645. [PMID: 31292867 DOI: 10.1007/s11356-019-05876-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 07/01/2019] [Indexed: 06/09/2023]
Abstract
One of the most common anthropogenic impacts on river ecosystems is the effluent discharge from wastewater treatment plants. The effects of this contamination on stream biota may be intensified in Mediterranean climate regions, which comprise a drought period that leads to flow reduction, and ultimately to stagnant pools. To assess individual and combined effects of flow stagnation and sewage contamination, biofilm and gastropod grazers were used in a 5-week experiment with artificial channels to test two flow velocity treatments (stagnant flow/basal flow) and two levels of organic contamination using artificial sewage (no sewage input/sewage input). Stressors' effects were determined on biofilm total biomass and chlorophyll (Chl) content, on oxygen consumption and growth rate of the grazers (Theodoxus fluviatilis), and on the interaction grazer-biofilm given by grazer's feeding activity (i.e., biofilm consumption rate). The single effect of sewage induced an increase in biofilm biomass and Chl-a content, simultaneously increasing both grazers' oxygen consumption and their feeding activity. Diatoms showed a higher sensitivity to flow stagnation, resulting in a lower content of Chl-c. Combined stressors interacted antagonistically for biofilm total biomass, Chl-b contents, and grazers's feeding rate. The effect of sewage increasing biofilm biomass and grazing activity was reduced by the presence of flow stagnation (antagonist factor). Our findings suggest that sewage contamination has a direct effect on the functional response of primary producers and an indirect effect on primary consumers, and this effect is influenced by water flow stagnation.
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Affiliation(s)
- Ana Raquel Calapez
- LEAF - Linking Landscape, Environment, Agriculture and Food, School of Agriculture, University of Lisbon, Lisbon, Portugal.
- MARE - Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal.
| | - Carmen L Elias
- Department of Biology and GeoBioTec - GeoBioSciences, GeoTechnologies and GeoEngineering Research Centre, University of Aveiro, Aveiro, Portugal
| | - Salomé F P Almeida
- Department of Biology and GeoBioTec - GeoBioSciences, GeoTechnologies and GeoEngineering Research Centre, University of Aveiro, Aveiro, Portugal
| | - António G Brito
- LEAF - Linking Landscape, Environment, Agriculture and Food, School of Agriculture, University of Lisbon, Lisbon, Portugal
| | - Maria João Feio
- MARE - Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal
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Xu Z, Fan Y, Wang T, Huang Y, MahmoodPoor Dehkordy F, Dai Z, Xia L, Dong Q, Bagtzoglou A, McCutcheon J, Lei Y, Li B. Towards high resolution monitoring of water flow velocity using flat flexible thin mm-sized resistance-typed sensor film (MRSF). Water Res X 2019; 4:100028. [PMID: 31334492 PMCID: PMC6614588 DOI: 10.1016/j.wroa.2019.100028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 03/12/2019] [Accepted: 03/18/2019] [Indexed: 05/12/2023]
Abstract
Novel flexible thin mm-sized resistance-typed sensor film (MRSF) fabricated using ink-jet printing technology (IPT) was developed in this study to monitor water flow rate in pipelines in real time in situ mode. The mechanism of MRSF is that the mm-sized interdigitated electrodes made by printing silver nanoparticles on an elastic polyimide film bend under different flow rates, leading to variation of the resistance of the sensor at different degrees of curvature. Continuous flow tests showed that MRSF possessed a high accuracy (0.2 m/s) and excellent sensitivity (0.1447/ms-1). A model of sensor resistance and flow velocity was established to unfold the correlation between the fundamentals of fluid mechanics and the mechanic flexibility of sensor materials. An analytical model yielded a high coefficient of determination (R2 > 0.93) for the relationship between the resistance increment of the MRSF and the square of the flow velocity at the velocity range of 0.25-2 m/s. Furthermore, a temperature-correction model was developed to quantify the effect of water temperature on the sensor resistance readings. MRSF exhibited a low temperature coefficient of resistance (TCR, 0.001) at the water temperature range of 20-60 °C. Computational fluid dynamics (CFD) simulations using the finite element method were conducted and confirmed both the underlying load assumptions and the deformation characteristics of the sensor film under various flow and material conditions. High-resolution monitoring of water flow rate using MRSF technology was expected to save at least 50% energy consumption for a given unit, especially under flow fluctuation. MRSF possesses a great potential to perform real-time in situ monitoring at high accuracy with ultralow cost, thus enabling the feedback control at high spatiotemporal resolution to reduce the overall energy consumption in water and wastewater systems.
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Affiliation(s)
- Zhiheng Xu
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Yingzheng Fan
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Tianbao Wang
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Yuankai Huang
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Farzaneh MahmoodPoor Dehkordy
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Zheqin Dai
- School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Lingling Xia
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Qiuchen Dong
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Amvrossios Bagtzoglou
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Jeffrey McCutcheon
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Yu Lei
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Baikun Li
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
- Corresponding author. Tel.: +860 486 2339.
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Wang HH, Tseng WYI, Yu HY, Chang MC, Peng HH. Phase-contrast magnetic resonance imaging for analyzing hemodynamic parameters and wall shear stress of pulmonary arteries in patients with pulmonary arterial hypertension. MAGMA 2019; 32:617-627. [PMID: 31270715 DOI: 10.1007/s10334-019-00767-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 05/29/2019] [Accepted: 06/24/2019] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To investigate flow-related parameters in pulmonary arteries of patients with pulmonary arterial hypertension (PAH). MATERIALS AND METHODS Eleven PAH patients and twelve control participants were recruited. PAH and controls had similar age and gender distribution. 2D phase-contrast MRI (PC-MRI) was performed in the main, right, and left pulmonary artery (MPA, RPA, and LPA). The flow velocity, wall shear stress (WSS), and oscillatory shear index (OSI) were measured. RESULTS PAH patients displayed prolonged acceleration time (Tacce) and increased ratio of flow change to acceleration volume in pulmonary arteries (both P < 0.001). The temporally averaged WSS values of MPA, RPA, and LPA in PAH patients were significantly lower than those of control participants (P < 0.001). The OSI in the pulmonary arteries was higher in PAH patients than control participants (P < 0.05). The ROC analysis indicated the ratio of maximum flow change to acceleration volume, WSS, and Tacce exhibited sufficient sensitivity and specificity to detect patients with PAH. The WSS demonstrated strong correlations with Tacce and the ratio value in the two groups (R2 = 0.78-0.96). CONCLUSIONS We used a clinically feasible 2D PC-MRI sequence with a reasonable scanning time to compute aforementioned indices. The quantitative parameters provided sufficient information to differentiate PAH patients from control participants.
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Affiliation(s)
- Hung-Hsuan Wang
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, BMES Building, R415, Hsinchu, 30013, Taiwan
| | - Wen-Yih Isaac Tseng
- Institute of Medical Device and Imaging, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsi-Yu Yu
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Meng-Chu Chang
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, BMES Building, R415, Hsinchu, 30013, Taiwan
| | - Hsu-Hsia Peng
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, BMES Building, R415, Hsinchu, 30013, Taiwan.
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Buzier R, Guibal R, Lissalde S, Guibaud G. Limitation of flow effect on passive sampling accuracy using POCIS with the PRC approach or o-DGT: A pilot-scale evaluation for pharmaceutical compounds. Chemosphere 2019; 222:628-636. [PMID: 30731383 DOI: 10.1016/j.chemosphere.2019.01.181] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 12/14/2018] [Accepted: 01/29/2019] [Indexed: 05/28/2023]
Abstract
Flow velocity is known to alter passive sampling accuracy. We investigated the POCIS (Polar Organic Chemical Integrative Sampler) with PRC (Performance Reference Compounds) approach and Diffusive Gradients in Thin Films samplers (o-DGT) to limit the effect of flow on the quantification accuracy of ten model pharmaceuticals compounds (0.16 ≤ log KOW ≤ 4.51). POCIS and o-DGT samplers were exposed for seven days in controlled pilot-scale (hundreds of liters) experiments under quiescent or flowing (2 < V < 18 cm s-1) conditions. Under flowing conditions, both POCIS-PRC and o-DGT efficiently limited the flow effect and led, in most cases, to biases within analytical uncertainty (20%). Under quiescent conditions, o-DGT performed accurately (bias < 30% for most compounds) whereas the PRC approach was unsuitable to improve upon the accuracy of POCIS (PRC was unable to desorb). Therefore, both approaches are helpful in limiting the effects of flow on accuracy, but only o-DGT is efficient in quiescent conditions. However, o-DGT currently suffers from poorer sensitivity compared to POCIS, but the future development of o-DGT devices with wider windows could overcome this limitation.
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Affiliation(s)
- Rémy Buzier
- University of Limoges, PEIRENE URA IRSTEA, Equipe DIQeau, 123 Avenue Albert Thomas, 87060, Limoges Cedex, France.
| | - Robin Guibal
- University of Limoges, PEIRENE URA IRSTEA, Equipe DIQeau, 123 Avenue Albert Thomas, 87060, Limoges Cedex, France
| | - Sophie Lissalde
- University of Limoges, PEIRENE URA IRSTEA, Equipe DIQeau, 123 Avenue Albert Thomas, 87060, Limoges Cedex, France
| | - Gilles Guibaud
- University of Limoges, PEIRENE URA IRSTEA, Equipe DIQeau, 123 Avenue Albert Thomas, 87060, Limoges Cedex, France
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Li X, Ji L, Wu L, Gao X, Li X, Li J, Liu Y. Effect of flow velocity on the growth, stress and immune responses of turbot (Scophthalmus maximus) in recirculating aquaculture systems. Fish Shellfish Immunol 2019; 86:1169-1176. [PMID: 30599254 DOI: 10.1016/j.fsi.2018.12.066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 12/22/2018] [Accepted: 12/28/2018] [Indexed: 06/09/2023]
Abstract
Land-based recirculating aquaculture systems (RAS) are widely utilized for turbot (Scophthalmus maximus) culture. Flow velocity in the tank is essential to maintain water quality, conservation of energy and fish welfare. However, little is known about how turbot respond to different velocities in the long term. In this study, water quality was kept constant, allowing the effect of flow velocity on the feeding intake, growth, plasma biochemical indexes, innate (non-specific) immunity and immune-related stress gene expressions in the skin to be examined in isolation in RAS. Turbot (average body length 20.10 cm) were reared for 60 days in RAS under three velocities, 0.06 m s-1, 0.18 m s-1, and 0.36 m s-1, corresponding to approximately 0.3 body length per second (bl s-1), 0.9 bl s-1 and 1.8 bl s-1, respectively. The results showed that at velocities of 0.36 m s-1 (1.8 bl s-1), juvenile turbot were subject to stress accompanied by a reduced growth rate. A velocity of 0.36 m s-1 was also found to significantly reduce SOD and GSH activity, and the concentration of total protein in plasma, while concentrations of urea nitrogen (BUN) and total bilirubin (TBIL) increased. There was an up-regulation of cathepsin D and lysozyme (LZM) in the skin at the highest velocity, implying the activation of stress and immune responses. At the medium velocity of 0.18 m s-1 (0.9 bl s-1), turbot increased their feed intake, obtained an elevated special growth rate (SGR), and exhibited significantly higher AKP and ACP activity in plasma. Overall, the results suggest that excessively high velocities are a stressor for turbot inducing an immune response in the skin, which is sensitive to environmental changes. A velocity of approximately 0.9 bl s-1 is suggested to promote growth and obtain better innate immunity of cultured turbot.
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Affiliation(s)
- Xian Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China
| | - Liqin Ji
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Lele Wu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Xiaolong Gao
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Xueqin Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Jun Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Ying Liu
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; School of Marine Science and Environmental Engineering, Dalian Ocean University, Dalian, 116023, China.
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40
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Calapez AR, Serra SRQ, Santos JM, Branco P, Ferreira T, Hein T, Brito AG, Feio MJ. The effect of hypoxia and flow decrease in macroinvertebrate functional responses: A trait-based approach to multiple-stressors in mesocosms. Sci Total Environ 2018; 637-638:647-656. [PMID: 29758421 DOI: 10.1016/j.scitotenv.2018.05.071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/04/2018] [Accepted: 05/05/2018] [Indexed: 06/08/2023]
Abstract
River ecosystems are most often subject to multiple co-occurring anthropogenic stressors. Mediterranean streams are particularly affected by water scarcity and organic loads that commonly lead to a simultaneous reduction in flow and increasing depletion of dissolved oxygen. In the present study, the single and combined effects of water scarcity (flow velocity reduction) and dissolved oxygen depletion were used to evaluate alterations of drifting macroinvertebrates on a channel mesocosm system, by employing a multiple trait-based approach. Our main findings confirmed that the impact of the two combined stressors can be implicated in alterations of ecosystem functions as result of the changes in proportions of biological traits. Overall, our results showed that, individually, flow velocity reduction and a severe oxygen depletion promoted a shift in community traits. In more detail, biological traits describing the dispersal of organisms and their respiration showed the strongest responses. The respiration mode responded to low flow with drift increase of gill breathers and decrease of individuals with tegument, whereas dispersal was clearly affected by the combination of stressors. Resistance through eggs was higher with the single effect of flow reduction, while swimmers´ relative abundance increased in individuals that drift after exposure to the combination of stressors. Thus, while flow reduction alone is expected to specifically filter out the gill breathers and the egg producers, the combination of stressors will impact more drastically organism's dispersal and swimmers. Such changes in biological traits can result in variations in ecosystem functioning through, for example, local changes in biomass, secondary production, stream metabolism as well as resulting in biodiversity losses or alterations of its distribution patterns.
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Affiliation(s)
- A R Calapez
- LEAF - Linking Landscape, Environment, Agriculture and Food, School of Agriculture, University of Lisbon, Lisbon, Portugal; MARE - Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.
| | - S R Q Serra
- MARE - Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - J M Santos
- CEF - Forest Research Centre, School of Agriculture, University of Lisbon, Lisbon, Portugal
| | - P Branco
- CEF - Forest Research Centre, School of Agriculture, University of Lisbon, Lisbon, Portugal; CERIS - Civil Engineering for Research and Innovation for Sustainability, Instituto Superior Técnico, University of Lisbon, Lisbon, Portugal
| | - T Ferreira
- CEF - Forest Research Centre, School of Agriculture, University of Lisbon, Lisbon, Portugal
| | - T Hein
- Institute of Hydrobiology and Aquatic Ecosystem Management, Department of Water, Atmosphere and Environment, University of Natural Resources and Life Sciences, Vienna, Austria
| | - A G Brito
- LEAF - Linking Landscape, Environment, Agriculture and Food, School of Agriculture, University of Lisbon, Lisbon, Portugal
| | - M J Feio
- MARE - Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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41
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Djomte VT, Taylor RB, Chen S, Booij K, Chambliss CK. Effects of hydrodynamic conditions and temperature on polar organic chemical integrative sampling rates. Environ Toxicol Chem 2018; 37:2331-2339. [PMID: 29978495 DOI: 10.1002/etc.4225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/15/2018] [Accepted: 07/03/2018] [Indexed: 06/08/2023]
Abstract
The effects of changing hydrodynamic conditions and changing temperatures on polar organic chemical integrative sampler (POCIS) sampling rates (Rs ) were investigated for 12 crop protection chemicals. Exposure concentration was held constant in each laboratory experiment, and flow velocities were calculated from measured mass transfer coefficients of the water boundary layer near the surface of POCIS devices. At a given temperature Rs generally increased by a factor of 2 to 5 between a stagnant condition and higher flow velocities (6-21 cm/s), but Rs for most compounds was essentially constant between the higher flow velocities. When temperature was varied between 8 and 39 °C for a given flow condition, Rs increased linearly. In general, Rs increased by a factor of 2 to 4 and 2 to 8 over this temperature range under flow and stagnant conditions, respectively. An Arrhenius model was used to describe the dependence of POCIS sampling rates on temperature. Adjustments of Rs for temperature did not fully explain observed differences between time-weighted average concentrations of atrazine determined from POCIS and from composite water sampling in a field setting, suggesting that the effects of other competing factors still need to be evaluated. Environ Toxicol Chem 2018;37:2331-2339. © 2018 SETAC.
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Affiliation(s)
| | - Raegyn B Taylor
- Baylor University, Department of Chemistry & Biochemistry, Waco, Texas, USA
| | - Sunmao Chen
- Syngenta Crop Protection, Greensboro, North Carolina, USA
| | | | - C Kevin Chambliss
- Baylor University, Department of Chemistry & Biochemistry, Waco, Texas, USA
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Castaldelli G, Aschonitis V, Vincenzi F, Fano EA, Soana E. The effect of water velocity on nitrate removal in vegetated waterways. J Environ Manage 2018; 215:230-238. [PMID: 29573673 DOI: 10.1016/j.jenvman.2018.03.071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 03/14/2018] [Accepted: 03/15/2018] [Indexed: 06/08/2023]
Abstract
The extended networks of canals and ditches in agricultural landscapes provide high buffer capacity towards nitrogen (N) excess. Their N mitigation potential depends on several biotic and abiotic factors, among which water velocity is poorly explored and generally omitted from the parameterization of this remarkable ecosystem service. The present work reports new insights on the role of flow velocity in regulating N removal via denitrification in sediments colonized by Phragmites australis. Denitrification was investigated in outdoor mesocosms in the presence and absence of P. australis and over a small range of flow velocity (0-6 cm s-1) typical of low-gradient water bodies. Simultaneous measurements of NO3- consumption and N2 production based on analyses of N2:Ar by Membrane Inlet Mass Spectrometry were undertaken. Vegetated sediments were found more efficient in converting NO3- to N2 via microbial-mediated denitrification (27-233 mmol N m-2 d-1) than bare sediments (18-33 mmol N m-2 d-1). Vegetation provides multiple interfaces, i.e. in the rhizosphere and on epiphytic biofilms, that support the development and activity of bacterial communities responsible for NO3- dissipation. NO3- removal and denitrification rates exhibited one order of magnitude raise when water velocity passed from 0 to 6 cm s-1 in vegetated sediments. Indeed, in slow-flow vegetated waterways denitrification may be physically limited and the increase of water velocity enhances the rate of NO3- supply through the diffusive boundary layer, thereby promoting its consumption and loss from the system. Water velocity should be taken into account as a key factor for management and restoration actions aimed at maximizing the NO3- buffer capacity of low-flow drainage networks.
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Affiliation(s)
- Giuseppe Castaldelli
- Department of Life Sciences and Biotechnology, University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy
| | - Vassilis Aschonitis
- Department of Life Sciences and Biotechnology, University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy
| | - Fabio Vincenzi
- Department of Life Sciences and Biotechnology, University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy
| | - Elisa Anna Fano
- Department of Life Sciences and Biotechnology, University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy
| | - Elisa Soana
- Department of Life Sciences and Biotechnology, University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy.
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Han J, Jiang H, Xu J, Hussain SA, Yuan X, Qin X. Hydraulic connection affects uranium distribution in the Gas Hure salt lake, Qaidam Basin, China. Environ Sci Pollut Res Int 2018; 25:4881-4895. [PMID: 29199369 DOI: 10.1007/s11356-017-0722-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/07/2017] [Indexed: 06/07/2023]
Abstract
The widespread hydraulic connection is necessary for the formation of a salt lake. However, only limited studies have ever been carried out to investigate the influence of the hydraulic connection on the distribution of elements around certain salt lake. In this study, a total of 66 water samples (including river water, stream water, spring water, brine, intercrystalline brine, well water, and drilling brine) were collected around the Gas Hure salt lake (GSKLH) to investigate the relationship between hydraulic connection and uranium (U) distribution via hydrochemistry and isotope (234U/238U, δ11B) techniques. The results suggested that the GSKLH was recharged by water from the Kulamulekesay and Atetikan rivers, groundwater (borehole brine and some intercrystalline brine), and deep fluid (some intercrystalline brine), with each contributing 44.03%, 14.95%, and 41.02% of total recharge, respectively. The U-bearing rock was dominated mainly by silicates, carbonates, and evaporites in the high mountain area (region 1), overflow area (region 2), and plain area (region 3) of the GSKLH, respectively. In the GSKLH, the U distribution was strongly correlated with hydraulic connection and the U concentration was influenced by both groundwater flow system and flow velocity (represented by the γCl-/γCa2+ ratio). Thus, U was enriched under the conditions of regional groundwater flow system and slow velocity in the GSKLH.
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Affiliation(s)
- Jibin Han
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, People's Republic of China
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, Hubei, People's Republic of China
- Key Laboratory of Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Xining, 81008, Qinghai, People's Republic of China
| | - Hongchen Jiang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, Hubei, People's Republic of China.
| | - Jianxin Xu
- Key Laboratory of Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Xining, 81008, Qinghai, People's Republic of China
| | - Syed Asim Hussain
- Key Laboratory of Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Xining, 81008, Qinghai, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Xiaolong Yuan
- Key Laboratory of Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Xining, 81008, Qinghai, People's Republic of China
| | - Xiwei Qin
- Key Laboratory of Salt Lake Geology and Environment of Qinghai Province, Qinghai Institute of Salt Lakes, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Xining, 81008, Qinghai, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
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Joachim J, Vallée F, Le Gall A, Matéo J, Lenck S, Millasseau S, Houdart E, Mebazaa A, Gayat E. Velocity-pressure loops for continuous assessment of ventricular afterload: influence of pressure measurement site. J Clin Monit Comput 2017; 32:833-840. [PMID: 29188414 DOI: 10.1007/s10877-017-0082-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 11/16/2017] [Indexed: 01/07/2023]
Abstract
VPloop, the graphical representation of pressure versus velocity, and its characteristic angles, GALA and β, can be used to monitor cardiac afterload during anesthesia. Ideally VPloop should be measured from pressure and velocity obtained at the same arterial location but standard of care usually provide either radial or femoral pressure waveforms. The purpose of this study was to look at the influence of arterial sites and the use of a transfer function (TF) on VPloop and its related angles. Invasive pressure signals were recorded in 25 patients undergoing neuroradiology intervention under general anesthesia with transesophageal flow velocity monitoring. Pressures were recorded in the descending thoracic aorta, abdominal aorta, femoral and radial arteries. We compared GALA and β from VPloops generated from each location and in high and low risk patients. GALA was similar in the central locations (55°[49-63], 52°[47-61] and 54°[45-62] from descending thoracic to femoral artery, median[interquartile], p = 0.10), while there was a difference in β angle (16°[4-27] to 8°[3-15], p < 0.0001). GALA and β obtained from radial waveforms were different (39°[31-47] compared to 46°[36-54] and 6°[2-14] compared to 16°[4-27] for GALA and β angles respectively, p < 0.001) which was corrected by the use of a TF (45°[32-55] and 17°[5-28], p = ns). GALA and β are underestimated when measured with a radial catheter. Using pressure waveforms from femoral locations alters VPloops, GALA and β in a smaller extend. The use of a TF on radial pressure allows to correctly plot VPloops and their characteristic angles for routine clinical use.
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Affiliation(s)
- Jona Joachim
- Department of Anesthesiology and Critical Care, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France.
- INSERM UMR-942, Paris, France.
- Paris Diderot University, Paris, France.
- LMS Polytechnique and M3DISIM, Inria, Saclay, France.
- Anesthesiology - Intensive Care - SMUR Department, Saint Louis-Lariboisière-Fernand Widal University Hospitals, 2 Rue Ambroise Paré, 75010, Paris, France.
| | - Fabrice Vallée
- Department of Anesthesiology and Critical Care, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
- INSERM UMR-942, Paris, France
- Paris Diderot University, Paris, France
- LMS Polytechnique and M3DISIM, Inria, Saclay, France
| | - Arthur Le Gall
- Department of Anesthesiology and Critical Care, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
- INSERM UMR-942, Paris, France
- Paris Diderot University, Paris, France
| | - Joaquim Matéo
- Department of Anesthesiology and Critical Care, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
- Paris Diderot University, Paris, France
| | - Stéphanie Lenck
- Department of Neuroradiology, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
| | | | - Emmanuel Houdart
- Department of Neuroradiology, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Alexandre Mebazaa
- Department of Anesthesiology and Critical Care, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
- INSERM UMR-942, Paris, France
- Paris Diderot University, Paris, France
| | - Etienne Gayat
- Department of Anesthesiology and Critical Care, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique - Hôpitaux de Paris, Paris, France
- INSERM UMR-942, Paris, France
- Paris Diderot University, Paris, France
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45
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Yasuoka R, Kurita T, Kotake Y, Akaiwa Y, Hashiguchi N, Motoki K, Yamamoto H, Kobuke K, Iwanaga Y, Hirano Y, Miyazaki S. A novel method to estimate blood flow velocity in the left atrial appendage using enhanced computed tomography: role of Hounsfield unit density ratio at two distinct points within the left atrial appendage. Heart Vessels 2017; 32:893-901. [PMID: 28130587 DOI: 10.1007/s00380-016-0931-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/09/2016] [Indexed: 10/20/2022]
Abstract
Low blood flow velocity in the left atrial appendage (LAA) indicates a high risk of thromboembolism. Although transesophageal echocardiography (TEE) has been the standard method with which to evaluate the LAA blood flow velocity, a clinically noninvasive method is desired. We hypothesized that the ratio of the Hounsfield unit (HU) density at two distinct points within the LAA represents the blood flow velocity in the LAA. We retrospectively investigated 60 consecutive patients with atrial fibrillation (paroxysmal type, n = 29) who underwent enhanced computed tomography (CT) and TEE. The peak emptying flow velocity in the LAA (LAAPV) was evaluated using TEE. HU density was measured at proximal and distal sites of the LAA (LAAp and LAAd) on CT images. The LAAd/LAAp ratio was correlated with the LAAPV (P < 0.01, r = 0.69). Among several indices, the HU ratio was the most significant parameter associated with the LAAPV (β = 0.469, CI 28.602-68.286, P < 0.001). Receiver-operating characteristic analysis (area under the curve, 0.91) demonstrated that an HU density ratio cutoff of 0.32 discriminated a low LAAPV (<25 cm/s) with sensitivity of 90% and specificity of 84%. Flow velocity of the LAA can be estimated by the HU density ratio at distal and proximal sites within the LAA. Our method might be a feasible substitution for TEE to discriminate patients with a reduced LAAPV.
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46
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Jovanovic D, Coleman R, Deletic A, McCarthy DT. Tidal fluctuations influence E. coli concentrations in urban estuaries. Mar Pollut Bull 2017; 119:226-230. [PMID: 28396075 DOI: 10.1016/j.marpolbul.2017.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 04/03/2017] [Accepted: 04/03/2017] [Indexed: 06/07/2023]
Abstract
This study investigated the influence of water level and velocity on Escherichia coli levels over multiple tidal cycles in an urban microtidal estuary in Melbourne, Australia. Over 3,500 E. coli samples and high resolution water level and velocity measurements from two locations within the estuary were used for the analysis. E. coli negatively correlated with water level in the upper estuary which was proposed to be linked to increased resuspension of estuarine sediments during low tide. No relationship was found in the lower estuary, likely due to wet weather inputs dwarfing subtler tidal-related processes. Removal of wet weather data enabled significant relationships to emerge in the lower estuary: 1) positive with water level (when a 9-h shift applied corresponding to the phase shift between water levels and velocities) and; 2) positive with velocity (no shift applied). This supports a link between increased E. coli levels and tidal-related resuspension.
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Affiliation(s)
- Dusan Jovanovic
- Environmental and Public Health Microbiology (EPHM) Laboratory, Monash Infrastructure Institute, Department of Civil Engineering, Monash University, Clayton, Victoria 3800, Australia.
| | - Rhys Coleman
- Melbourne Water Corporation, Docklands, Victoria 3008, Australia.
| | - Ana Deletic
- Environmental and Public Health Microbiology (EPHM) Laboratory, Monash Infrastructure Institute, Department of Civil Engineering, Monash University, Clayton, Victoria 3800, Australia.
| | - David T McCarthy
- Environmental and Public Health Microbiology (EPHM) Laboratory, Monash Infrastructure Institute, Department of Civil Engineering, Monash University, Clayton, Victoria 3800, Australia.
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47
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Zhou X, Xia C, Stephen G, Khan F, Corner GA, Hoskins PR, Huang Z. Investigation of Ultrasound-Measured Flow Velocity, Flow Rate and Wall Shear Rate in Radial and Ulnar Arteries Using Simulation. Ultrasound Med Biol 2017; 43:981-992. [PMID: 28236532 DOI: 10.1016/j.ultrasmedbio.2016.12.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Revised: 12/02/2016] [Accepted: 12/31/2016] [Indexed: 06/06/2023]
Abstract
Parameters of blood flow measured by ultrasound in radial and ulnar arteries, such as flow velocity, flow rate and wall shear rate, are widely used in clinical practice and clinical research. Investigation of these measurements is useful for evaluating accuracy and providing knowledge of error sources. A method for simulating the spectral Doppler ultrasound measurement process was developed with computational fluid dynamics providing flow-field data. Specific scanning factors were adjusted to investigate their influence on estimation of the maximum velocity waveform, and flow rate and wall shear rate were derived using the Womersley equation. The overestimation in maximum velocity increases greatly (peak systolic from about 10% to 30%, time-averaged from about 30% to 50%) when the beam-vessel angle is changed from 30° to 70°. The Womersley equation was able to estimate flow rate in both arteries with less than 3% error, but performed better in the radial artery (2.3% overestimation) than the ulnar artery (15.4% underestimation) in estimating wall shear rate. It is concluded that measurements of flow parameters in the radial and ulnar arteries with clinical ultrasound scanners are prone to clinically significant errors.
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Affiliation(s)
- Xiaowei Zhou
- School of Science and Engineering, University of Dundee, Dundee, United Kingdom
| | - Chunming Xia
- School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, China; NHS Tayside Medical Physics, Ninewells Hospital, Dundee, United Kingdom
| | - Gandy Stephen
- School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, China; NHS Tayside Medical Physics, Ninewells Hospital, Dundee, United Kingdom
| | - Faisel Khan
- Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom
| | - George A Corner
- School of Science and Engineering, University of Dundee, Dundee, United Kingdom
| | - Peter R Hoskins
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Zhihong Huang
- School of Science and Engineering, University of Dundee, Dundee, United Kingdom.
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Lv X, Tao J, Chen B, Zhu X. Roles of temperature and flow velocity on the mobility of nano-sized titanium dioxide in natural waters. Sci Total Environ 2016; 565:849-856. [PMID: 26970667 DOI: 10.1016/j.scitotenv.2016.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/01/2016] [Accepted: 03/01/2016] [Indexed: 06/05/2023]
Abstract
While environmental fate and transport of nano-sized TiO2 (nTiO2) attracts intensive attention, how physical characters of natural waters, such as water type, temperature, and flowing velocity, impact the mobility of nTiO2 remain unclear now. In this work, ultrapure water, lake water, and sea water were chosen to investigate the aggregation and sedimentation behaviors of nTiO2 under a series of environmental conditions with varying feeding concentration, water temperature, and flow velocity. In general, the results demonstrated poorer stability of nTiO2 in sea water than other water types. After a 7-hour test (initial nTiO2=100mg/L), the nTiO2 hydrodynamic sizes, sedimentation rates, and zeta potentials differed significantly in ultrapure water (545nm, 24%, -30mV), lake water (1374nm, 56%, -16mV) and sea water (2152nm, 87%, -3mV). Meanwhile, the study exhibited significant influences of initial nTiO2 concentration (10-100mg/L) on the behaviors of nTiO2 in sea water and lake water but negligible impact on ultrapure water. Ambient temperature also directly affected the aggregation and sedimentation rates of nTiO2, both hydrodynamic diameters and sedimentation of nTiO2 increased markedly with the rising ambient temperatures (10-60°C). In contrast, increasing water flow velocity (0-0.32m/s) lowered the hydrodynamic diameters and sedimentation rates of nTiO2, although the influence of flowing velocity on the aggregation of nTiO2 was partially reversible.
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Affiliation(s)
- Xiaohui Lv
- Harbin Institute of Technology Shenzhen Graduate School, China; Graduate School at Shenzhen, Tsinghua University, China
| | - Jing Tao
- Harbin Institute of Technology Shenzhen Graduate School, China; Graduate School at Shenzhen, Tsinghua University, China
| | - Baiyang Chen
- Harbin Institute of Technology Shenzhen Graduate School, China.
| | - Xiaoshan Zhu
- Graduate School at Shenzhen, Tsinghua University, China.
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49
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Lenzarini F, Di Lascio N, Stea F, Kusmic C, Faita F. Time Course of Isoflurane-Induced Vasodilation: A Doppler Ultrasound Study of the Left Coronary Artery in Mice. Ultrasound Med Biol 2016; 42:999-1009. [PMID: 26792616 DOI: 10.1016/j.ultrasmedbio.2015.11.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 11/19/2015] [Accepted: 11/30/2015] [Indexed: 06/05/2023]
Abstract
Isoflurane is widely used as vasodilator in studies of coronary flow reserve (CFR) in small animals, but the protocols have not been standardized. This study assessed the time course of the increase in isoflurane-induced flow in the mouse coronary artery by pulsed-wave Doppler measurements at 1% isoflurane concentration maintained for 6 min and then increased to 2.5% for 30 min. Velocity-time integral and velocity peak values were best fitted by the sigmoid model, which allowed derivation of the mean time (Tt90 = 14 min) of high-isoflurane needed to reach 90% of the hyperemic plateau value. In subsequent experiments, CFR was measured at 4 min (mean time of literature data) and 14 min of hyperemic response. The 4-min CFR was significantly lower than the 14 -min CFR, and the Bland-Altman plot revealed significant bias of the 4-min CFR against the 14-min CFR. This result suggests that measurements of flow velocity at times shorter than 14 min may be inappropriate for expressing the effective value of CFR.
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Affiliation(s)
| | - Nicole Di Lascio
- Institute of Clinical Physiology, National Research Council, Pisa, Italy; Institute of Life Sciences, Scuola Superiore Sant'Anna, P.zza Martiri della Libertà, Pisa, Italy
| | - Francesco Stea
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Claudia Kusmic
- Institute of Clinical Physiology, National Research Council, Pisa, Italy.
| | - Francesco Faita
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
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50
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Freidman BL, Gras SL, Snape I, Stevens GW, Mumford KA. Application of controlled nutrient release to permeable reactive barriers. J Environ Manage 2016; 169:145-154. [PMID: 26735866 DOI: 10.1016/j.jenvman.2015.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/29/2015] [Accepted: 12/05/2015] [Indexed: 06/05/2023]
Abstract
The application of controlled release nutrient (CRN) materials to permeable reactive barriers to promote biodegradation of petroleum hydrocarbons in groundwater was investigated. The longevity of release, influence of flow velocity and petroleum hydrocarbon concentration on nutrient release was assessed using soluble and ion exchange CRN materials; namely Polyon™ and Zeopro™. Both CRN materials, assessed at 4 °C and 23 °C, demonstrated continuing release of nitrogen, phosphorus and potassium (N-P-K) at 3500 bed volumes passing, with longer timeframes of N-P-K release at 4 °C. Zeopro™-activated carbon mixtures demonstrated depletion of N-P-K prior to 3500 bed volumes passing. Increased flow velocity was shown to lower nutrient concentrations in Polyon™ flow cells while nutrient release from Zeopro™ was largely unchanged. The presence of petroleum hydrocarbons, at 1.08 mmol/L and 3.25 mmol/L toluene, were not shown to alter nutrient release from Polyon™ and Zeopro™ across 14 days. These findings suggest that Polyon™ and Zeopro™ may be suitable CRN materials for application to PRBs in low nutrient environments.
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Affiliation(s)
- Benjamin L Freidman
- Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, VIC 3010, Australia; Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia
| | - Sally L Gras
- Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, VIC 3010, Australia; Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia; The ARC Dairy Innovation Hub, The University of Melbourne, VIC 3010, Australia
| | - Ian Snape
- Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia
| | - Geoff W Stevens
- Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, VIC 3010, Australia
| | - Kathryn A Mumford
- Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, The University of Melbourne, VIC 3010, Australia.
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