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Liu W, Qin T, Wu M, Chen Z, Zhang Y, Abakumov E, Chebykina E, Wang W, Wu D, Han C, Xie X, Cheng J, Hua X, Chi S, Xu J. Analyzing the phosphorus flow characteristics in the largest freshwater lake (Poyang Lake) watershed of China from 1950 to 2020 through a bottom-up approach of watershed-scale phosphorus substance flow model. WATER RESEARCH 2023; 245:120546. [PMID: 37688855 DOI: 10.1016/j.watres.2023.120546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/11/2023]
Abstract
Understanding the historical patterns of phosphorus (P) cycling is essential for sustainable P management and eutrophication mitigation in watersheds. Currently, there is a lack of long-term watershed-scale models that analyze the flow of P substances and quantify the socioeconomic patterns of P flow. This study adopted a watershed perspective and incorporated crucial economic and social subsystems related to P production, consumption, and emissions throughout the entire life cycle. Based on this approach, a bottom-up watershed P flow analysis model was developed to quantify the P cycle for the first time in the Poyang Lake watershed from 1950 to 2020 and to explore the driving factors that influence its strength by analyzing multi-year P flow results. In general, the P cycle in the Poyang Lake watershed was no longer a naturally dominated cycle but significantly influenced by human activities during the flow dynamics between 1950 and 2015. Agricultural intensification and expansion of large-scale livestock farming continue to enhance the P flow in the study area. Fertilizer P inputs from cultivation account for approximately 60% of the total inputs to farming systems, but phosphate fertilizer utilization continues to decline. Feed P inputs have continued to increase since 2007. The expansion of large-scale farming and the demand for urbanization are the main factors leading to changes in feed P input patterns. The P utilization rate for livestock farming (PUEa) is progressively higher than international levels, with PUEa increasing from 0.64% (1950) to 9.7% (2020). Additionally, per capita food P consumption in the watershed increased from 0.67 kg to 0.80 kg between 1950 and 2020. The anthropogenic P emissions have increased from 1.67 × 104 t (1950) to 8.73 × 104 t (2020), with an average annual growth rate of 2.41%. Watershed-wide P pollution emissions have increased by more than five-fold. Population growth and agricultural development are important drivers of structural changes in P flows in the study area, and they induce changes in social conditions, including agricultural production, dietary structure, and consumption levels, further dominating the cyclic patterns of P use, discharge, and recycling. This study provides a broader and applicable P flow model to measure the characteristics of the P cycle throughout the watershed social system as well as provides methodological support and policy insights for large lakes in rapidly developing areas or countries to easily present P flow structures and sustainably manage P resources.
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Xu W, Huang H, Li X, Yang M, Chi S, Pan Y, Li N, Paterson AH, Chai Y, Lu K. CaHMA1 promotes Cd accumulation in pepper fruit. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132480. [PMID: 37683343 DOI: 10.1016/j.jhazmat.2023.132480] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 08/30/2023] [Accepted: 09/03/2023] [Indexed: 09/10/2023]
Abstract
The main planting areas for pepper (Capsicum sp.) are high in cadmium (Cd), which is the most prevalent heavy metal pollutant worldwide. Breeding pepper cultivars with low Cd levels can promote sustainable agricultural production and ensure the safety of pepper products. To identify breeding targets for reducing Cd accumulation in pepper fruits, we performed a genome-wide association study on 186 accessions. Polymorphisms were associated with fruit Cd content in a genomic region containing a homolog of Arabidopsis (Arabidopsis thaliana) Heavy metal-transporting ATPase 1 (HMA1) encoding a P-type ATPase. In two cultivars with contrasting Cd accumulation, transcriptome analysis revealed differentially expressed genes enriched for carbohydrate metabolism and photosynthesis in fruits with high Cd accumulation, and a Cd2+/Zn2+-exporting ATPase gene (HMA). Heterologous expression of CaHMA1 in yeast increases Cd sensitivity. Overexpression of CaHMA1 conferred a severe increase in Cd content in Arabidopsis plants, whereas reduced CaHMA1 expression in pepper fruits decreased Cd content. We propose that CaHMA1 expression may be an important component of the high Cd accumulation in pepper plants.
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Chi S, Xu W, Han Y. ARGs distribution and high-risk ARGs identification based on continuous application of manure in purple soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 853:158667. [PMID: 36096231 DOI: 10.1016/j.scitotenv.2022.158667] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/30/2022] [Accepted: 09/07/2022] [Indexed: 06/15/2023]
Abstract
Tetracyclines (TCs) are one of the most widely used antibiotics in livestock and poultry industry. Sichuan province and Chongqing city are the provinces and cities with the most concentrated purple soil distribution in China, as well as the largest livestock and poultry breeding scale. Purple soils with low organic carbon content and poor structure, and manure fertilizers were heavily applied to improve soil quality. However, the research on antibiotic resistance genes (ARGs) dispersal in purple soils is limited. Overall, 234 ARGs subtypes belonging to 15 types were detected in all soils. Long-term application of livestock manures significantly changed the characteristics of ARGs, mobile genetic elements (MGEs), pathogen species and bacterial communities in the soil, and increased by 103.2 %, 13.1 %, 188.6 % and 43.7 % in chicken manure treatments compared with the control, respectively. Partial equation PLS-PM analysis further reveals that the main driving factor of ARGs is bacterial abundance, while bacterial diversity has a negative effect on ARGs abundance. Through ANOVA and network analysis, it was found that 30 ARGs were significantly affected by manure, its relative abundance is 0.8-1.4 times that of the control treatment. The qPCR results also proved that the relative abundance of ARGs including sul2, etc. increased with the increase of manure application and these resistance genes in chicken manure treatments were higher than in pig manure treatments. These resistance genes pose a high risk to public health, and chicken manure application posed a higher risk than pig manure. The TC content in the 40-60 cm soil layer was higher in medium- and high-volume pig manure, which was at risk of being transported to groundwater. Our research results deepen the understanding of ARGs transmission in purple soil under agricultural activities and emphasize the species and distribution of antibiotic resistance genes may differ across soil and manure types.
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DeRosa PA, Annitsakis D, Chi S, Akselrod H. Meningitis Multiplex-PCR: 3-Year Study of Cost and Correlation With Traditional Cerebrospinal Fluid Analysis. Am J Clin Pathol 2022. [DOI: 10.1093/ajcp/aqac126.284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract
Introduction/Objective
Physicians often rely on Cerebrospinal Fluid (CSF) cytology, chemistry, and culture. While cheap, these methods lack high sensitivity/specificity or have long turnaround times. PCR evaluation of CSF has become more common and is often touted as a way to save money, decrease turnaround times and quickly target antibiotics. PCR systems may cost $200,000, with $150 in disposables per test. As a new, fast, test it may be over ordered.
Methods/Case Report
Case-control study using retrospective chart review. All adults, aged 18 and over, who had undergone both PCR based testing and cytochemical testing between 3/1/2017 and 9/7/2019 were included.
Results (if a Case Study enter NA)
From 3/1/2017-9/7/2019, there were 381 available PCR results for adult GWUH patients. Demographic data showed that the patient sample was majority black (195/320, 60.94%), had an average age of 49.8 ± 17.2, and was majority female (172/320, 53.75%). The PCR results were 85.31% negative (273/320) and the CSF cultures were 94.38% negative. The most common PCR positive organism was Varicella zoster virus (11/47 positive results) and the most common CSF culture organism was Streptococcus pneumoniae (5/18 positive cultures).
Conclusion
In a population with clinical symptoms and at least 1 abnormality on CSF analysis, 6.5 tests were run for every positive PCR test. No single variable was found to significantly predict PCR results. Within a high initial cost, a disposable cost of $150 per test and detection rate of 14.7%, the cost to detect a single positive test by PCR could approach $4,500. PCR should be used judiciously following history, physical exam and standard CSF workup, rather than as a screening tool.
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Lanigan-Atkins T, Yang S, Niedziela JL, Bansal D, May AF, Puretzky AA, Lin JYY, Pajerowski DM, Hong T, Chi S, Ehlers G, Delaire O. Extended anharmonic collapse of phonon dispersions in SnS and SnSe. Nat Commun 2020; 11:4430. [PMID: 32887880 PMCID: PMC7474096 DOI: 10.1038/s41467-020-18121-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 08/09/2020] [Indexed: 11/12/2022] Open
Abstract
The lattice dynamics and high-temperature structural transition in SnS and SnSe are investigated via inelastic neutron scattering, high-resolution Raman spectroscopy and anharmonic first-principles simulations. We uncover a spectacular, extreme softening and reconstruction of an entire manifold of low-energy acoustic and optic branches across a structural transition, reflecting strong directionality in bonding strength and anharmonicity. Further, our results solve a prior controversy by revealing the soft-mode mechanism of the phase transition that impacts thermal transport and thermoelectric efficiency. Our simulations of anharmonic phonon renormalization go beyond low-order perturbation theory and capture these striking effects, showing that the large phonon shifts directly affect the thermal conductivity by altering both the phonon scattering phase space and the group velocities. These results provide a detailed microscopic understanding of phase stability and thermal transport in technologically important materials, providing further insights on ways to control phonon propagation in thermoelectrics, photovoltaics, and other materials requiring thermal management.
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Manley ME, Hong K, Yin P, Chi S, Cai Y, Hua C, Daemen LL, Hermann RP, Wang H, May AF, Asta M, Ahmadi M. Giant isotope effect on phonon dispersion and thermal conductivity in methylammonium lead iodide. SCIENCE ADVANCES 2020; 6:eaaz1842. [PMID: 32789169 PMCID: PMC7399528 DOI: 10.1126/sciadv.aaz1842] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 06/19/2020] [Indexed: 05/29/2023]
Abstract
Lead halide perovskites are strong candidates for high-performance low-cost photovoltaics, light emission, and detection applications. A hot-phonon bottleneck effect significantly extends the cooling time of hot charge carriers, which thermalize through carrier-optic phonon scattering, followed by optic phonon decay to acoustic phonons and finally thermal conduction. To understand these processes, we adjust the lattice dynamics independently of electronics by changing isotopes. We show that doubling the mass of hydrogen in methylammonium lead iodide by replacing protons with deuterons causes a large 20 to 50% softening of the longitudinal acoustic phonons near zone boundaries, reduces thermal conductivity by ~50%, and slows carrier relaxation kinetics. Phonon softening is attributed to anticrossing with the slowed libration modes of the deuterated molecules and the reduced thermal conductivity to lowered phonon velocities. Our results reveal how tuning the organic molecule dynamics enables control of phonons important to thermal conductivity and the hot-phonon bottleneck.
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Jaimes C, Vajapeyam S, Brown D, Kao PC, Ma C, Greenspan L, Gupta N, Goumnerova L, Bandopahayay P, Dubois F, Greenwald NF, Zack T, Shapira O, Beroukhim R, Ligon KL, Chi S, Kieran MW, Wright KD, Poussaint TY. MR Imaging Correlates for Molecular and Mutational Analyses in Children with Diffuse Intrinsic Pontine Glioma. AJNR Am J Neuroradiol 2020; 41:874-881. [PMID: 32381545 DOI: 10.3174/ajnr.a6546] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 03/16/2020] [Indexed: 01/13/2023]
Abstract
BACKGROUND AND PURPOSE Recent advances in molecular techniques have characterized distinct subtypes of diffuse intrinsic pontine gliomas. Our aim was the identification of MR imaging correlates of these subtypes. MATERIALS AND METHODS Initial MRIs from subjects with diffuse intrinsic pontine gliomas recruited for a prospective clinical trial before treatment were analyzed. Retrospective imaging analyses included FLAIR/T2 tumor volume, tumor volume enhancing, the presence of cyst and/or necrosis, median, mean, mode, skewness, kurtosis of ADC tumor volume based on FLAIR, and enhancement at baseline. Molecular subgroups based on EGFR and MGMT mutations were established. Histone mutations were also determined (H3F3A, HIST1H3B, HIST1H3C). Univariate Cox proportional hazards regression was used to test the association of imaging predictors with overall and progression-free survival. Wilcoxon rank sum, Kruskal-Wallis, and Fisher exact tests were used to compare imaging measures among groups. RESULTS Fifty patients had biopsy and MR imaging. The median age at trial registration was 6 years (range, 3.3-17.5 years); 52% were female. On the basis of immunohistochemical results, 48 patients were assigned to 1 of 4 subgroups: 28 in MGMT-/epidermal growth factor receptor (EGFR)-, 14 in MGMT-/EGFR+, 3 in MGMT+/EGFR-, and 3 in MGMT+/EGFR+. Twenty-three patients had histone mutations in H3F3A, 8 in HIST1H3B, and 3 in HIST1H3C. Enhancing tumor volume was near-significantly different across molecular subgroups (P = .04), after accounting for the false discovery rate. Tumor volume enhancing, median, mode, skewness, and kurtosis ADC T2-FLAIR/T2 were significantly different (P ≤ .048) between patients with H3F3A and HIST1H3B/C mutations. CONCLUSIONS MR imaging features including enhancement and ADC histogram parameters are correlated with molecular subgroups and mutations in children with diffuse intrinsic pontine gliomas.
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Kim MG, Winn B, Chi S, Savici AT, Rodriguez-Rivera JA, Chen WC, Xu X, Li Y, Kim JW, Cheong SW, Kiryukhin V. Spin-liquid-like state in pure and Mn-doped TbInO 3 with a nearly triangular lattice. PHYSICAL REVIEW. B 2019; 100:10.1103/PhysRevB.100.024405. [PMID: 38712019 PMCID: PMC11071068 DOI: 10.1103/physrevb.100.024405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Inelastic neutron scattering studies in single crystals of TbInO3 and TbIn0.95Mn0.05O3 with nearly triangular antiferromagnetic lattice are reported. At low energies, a broad and apparently gapless continuum of magnetic excitations, located at the triangular lattice (TL) Brillouin zone boundary, is observed. The data are well described by the uncorrelated nearest-neighbor valence bonds model. At higher energies, a broad excitation branch dispersing from the TL zone boundary is observed. No signs of static magnetic order are found down to the temperatures two orders of magnitude smaller than the effective interaction energy. The fluctuating magnetic moment exceeds two-thirds of the Tb3+ free-ion value and is confined to the TL plane. These observations are consistent with a TL-based spin liquid state in TbInO3.
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Chi S, Qin Y, Xu W, Chai Y, Feng D, Li Y, Li T, Yang M, He Z. Differences of Cd uptake and expression of OAS and IRT genes in two varieties of ryegrasses. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:13717-13724. [PMID: 29909534 DOI: 10.1007/s11356-018-2509-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 06/04/2018] [Indexed: 06/08/2023]
Abstract
Pot experiment was conducted to study the difference of cadmium uptake and OAS and IRT genes' expression between the two ryegrass varieties under cadmium stress. The results showed that with the increase of cadmium levels, the dry weights of roots of the two ryegrass varieties, and the dry weights of shoots and plants of Abbott first increased and then decreased. When exposed to 75 mg kg-1 Cd, the dry weights of shoot and plant of Abbott reached the maximum, which increased by 11.13 and 10.67% compared with the control. At 75 mg kg-1 Cd, cadmium concentrations in shoot of the two ryegrass varieties were higher than the critical value of Cd hyperaccumulator (100 mg kg-1), 111.19 mg kg-1 (Bond), and 133.69 mg kg-1 (Abbott), respectively. The OAS gene expression in the leaves of the two ryegrass varieties showed a unimodal curve, which was up to the highest at the cadmium level of 150 mg kg-1, but fell back at high cadmium levels of 300 and 600 mg kg-1. The OAS gene expression in Bond and Abbott roots showed a bimodal curve. The OAS gene expression in Bond root and Abbott stem mainly showed a unimodal curve. The expression of IRT genes family in the leaves of ryegrass varieties was basically in line with the characteristics of unimodal curve, which was up to the highest at cadmium level of 75 or 150 mg kg-1, respectively. The IRT expression in the ryegrass stems showed characteristics of bimodal and unimodal curves, while that in the roots was mainly unimodal. The expression of OAS and IRT genes was higher in Bond than that in Abbott due to genotype difference between the two varieties. The expression of OAS and IRT was greater in leaves than that in roots and stems. Ryegrass tolerance to cadmium can be increased by increasing the expression of OAS and IRT genes in roots and stems, and transfer of cadmium from roots and stems to the leaves can be enhanced by increasing expression OAS and IRT in leaves.
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Zhang C, Chen Y, Xu W, Chi S, Li T, Li Y, He Z, Yang M, Feng D. Resistance of alfalfa and Indian mustard to Cd and the correlation of plant Cd uptake and soil Cd form. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:13804-13811. [PMID: 30218333 DOI: 10.1007/s11356-018-3162-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 09/06/2018] [Indexed: 06/08/2023]
Abstract
Phytoremediation of heavy metal-contaminated soil is considered to be one ecological environmental protection way that is effective and economical. The selection of suitable hyperaccumulators is a key issue for phytoremediation of heavy metal-contaminated soil. Pot experiments were conducted to study the effects of different Cd levels (0, 75, 150, 300, and 600 mg kg-1 Cd) on the dry weight, antioxidant enzyme activities, malondialdehyde (MDA) contents, Cd concentration, Cd accumulation, and soil Cd form distribution ratio (FDC) of alfalfa (Medicago sativa L.) and Indian mustard (Brassica juncea L.). The correlations between Cd concentration in shoots and roots of alfalfa and Indian mustard and soil Cd form were also investigated. The results showed that with the increase of soil Cd levels, dry weight of shoot and root of alfalfa and Indian mustard significantly decreased, which decreased by 50.0-71.8% and 29.6-59.3% (alfalfa), 59.6-89.0% and 64.3-74.8% (India mustard), respectively, compared with the control. With the increase of soil Cd level, superoxide dismutase (SOD) activity in shoot of alfalfa significantly increased. Catalase (CAT) activity and malondialdehyde contents in shoots and roots of alfalfa and Indian mustard, as well as superoxide dismutase activity in the roots of alfalfa and Indian mustard increased first and then decreased with the increase of soil Cd level. With increasing Cd stress, Cd concentration in shoots and roots of alfalfa and Indian mustard significantly increased. At soil Cd level of 75 mg kg-1, Cd concentrations in shoots of alfalfa and Indian mustard exceeded the critical value of Cd-hyperaccumulator (100 mg kg-1), which was 356.46 mg kg-1 and 308.74 mg kg-1, respectively. Cadmium concentrations in shoots and roots of plants were in the order of that of alfalfa > Indian mustard; total Cd accumulation in the aboveground tissues and roots of the plants was in the order of that of Indian mustard > alfalfa at the same Cd level. With increasing soil Cd level, Cd concentrations of exchangeable form (EXC-Cd), carbonate-bound form (CAB-Cd), iron-manganese oxide-bound form (FeMn-Cd), organic-bound form (OM-Cd), and residual form (RES-Cd) showed an increasing trend. The form distribution ratio of soil Cd forms in alfalfa's rhizosphere was in the order of that of exchangeable form Cd > carbonate-bound form Cd > iron-manganese oxide-bound form Cd > residual form Cd > organic-bound form Cd. Except for organic-bound form Cd, soil Cd forms were significantly positively correlated with Cd concentration in shoot and root (P < 0.01). Comprehensively considering the biomass and Cd accumulation, Indian mustard is more suitable as remediation material for soil Cd pollution.
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Chi S, Liu JL, Kang HC, Lv DM. Continuous nursing intervention on recovery of diabetic patients. J BIOL REG HOMEOS AG 2018; 32:1507-1513. [PMID: 30574757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The aim of this study was to probe the influence of continuous nursing intervention on recovery of diabetic patients. From October 2016 to June 2017, 80 diabetic patients who received treatment in our hospital were selected and randomly divided into an intervention group and a control group. The intervention group received continuous nursing care including indirect follow-up, health education and home visit. The self-care ability and blood sugar of the two groups were compared three months later. The score of self-care ability in the intervention group was 89.64±1.64 and that in control group was 72.68±2.47, and a significant difference was observed (P less than 0.001). The fasting blood glucose level in the intervention group was 6.62±0.86 MMOL/L, and the 2-hour post-meal blood glucose level was 8.47±1.32 MMOL/L, which were both lower than those in the control group. Continuous nursing can help monitor the recovery of patients after discharge. It is helpful to improve the self-care ability of patients, control blood sugar level, and promote recovery. It is worth wide promotion.
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Day RP, Levy G, Michiardi M, Zwartsenberg B, Zonno M, Ji F, Razzoli E, Boschini F, Chi S, Liang R, Das PK, Vobornik I, Fujii J, Hardy WN, Bonn DA, Elfimov IS, Damascelli A. Influence of Spin-Orbit Coupling in Iron-Based Superconductors. PHYSICAL REVIEW LETTERS 2018; 121:076401. [PMID: 30169095 DOI: 10.1103/physrevlett.121.076401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 06/03/2018] [Indexed: 06/08/2023]
Abstract
We report on the influence of spin-orbit coupling (SOC) in Fe-based superconductors via application of circularly polarized spin and angle-resolved photoemission spectroscopy. We combine this technique in representative members of both the Fe-pnictides (LiFeAs) and Fe-chalcogenides (FeSe) with tight-binding calculations to establish an ubiquitous modification of the electronic structure in these materials imbued by SOC. At low energy, the influence of SOC is found to be concentrated on the hole pockets, where the largest superconducting gaps are typically found. This effect varies substantively with the k_{z} dispersion, and in FeSe we find SOC to be comparable to the energy scale of orbital order. These results contest descriptions of superconductivity in these materials in terms of pure spin-singlet eigenstates, raising questions regarding the possible pairing mechanisms and role of SOC therein.
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Stonaha PJ, Karaman I, Arroyave R, Salas D, Bruno NM, Wang Y, Chisholm MF, Chi S, Abernathy DL, Chumlyakov YI, Manley ME. Glassy Phonon Heralds a Strain Glass State in a Shape Memory Alloy. PHYSICAL REVIEW LETTERS 2018; 120:245701. [PMID: 29956961 DOI: 10.1103/physrevlett.120.245701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/30/2018] [Indexed: 06/08/2023]
Abstract
Shape memory strain glasses are frustrated ferroelastic materials with glasslike slow relaxation and nanodomains. It is possible to change a NiCoMnIn Heusler alloy from a martensitically transforming alloy to a nontransforming strain glass by annealing, but minimal differences are evident in the short- or long-range order above the transition temperature-although there is a structural relaxation and a 0.18% lattice expansion in the annealed sample. Using neutron scattering we find glasslike phonon damping in the strain glass but not the transforming alloy at temperatures well above the transition. Damping occurs in the mode with displacements matching the martensitic transformation. With support from first-principles calculations, we argue that the strain glass originates not with transformation strain pinning but with a disruption of the underlying electronic instability when disorder resonance states cross the Fermi level.
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Manley ME, Stonaha PJ, Abernathy DL, Chi S, Sahul R, Hermann RP, Budai JD. Supersonic propagation of lattice energy by phasons in fresnoite. Nat Commun 2018; 9:1823. [PMID: 29739934 PMCID: PMC5940883 DOI: 10.1038/s41467-018-04229-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 04/13/2018] [Indexed: 11/09/2022] Open
Abstract
Controlling the thermal energy of lattice vibrations separately from electrons is vital to many applications including electronic devices and thermoelectric energy conversion. To remove heat without shorting electrical connections, heat must be carried in the lattice of electrical insulators. Phonons are limited to the speed of sound, which, compared to the speed of electronic processes, puts a fundamental constraint on thermal management. Here we report a supersonic channel for the propagation of lattice energy in the technologically promising piezoelectric mineral fresnoite (Ba2TiSi2O8) using neutron scattering. Lattice energy propagates 2.8−4.3 times the speed of sound in the form of phasons, which are caused by an incommensurate modulation in the flexible framework structure of fresnoite. The phasons enhance the thermal conductivity by 20% at room temperature and carry lattice-energy signals at speeds beyond the limits of phonons. Fresnoite has an incommensurate structure that can be described as a nonlinear soliton lattice. Manley et al. show that the additional phason degrees of freedom associated with the solitonic structure can travel faster than more conventional phonon excitations, enabling supersonic energy transport.
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Rong Y, Padron AV, Hagerty KJ, Nelson N, Chi S, Keyhani NO, Katz J, Datta SPA, Gomes C, McLamore ES. Post hoc support vector machine learning for impedimetric biosensors based on weak protein–ligand interactions. Analyst 2018; 143:2066-2075. [DOI: 10.1039/c8an00065d] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We develop a simple, open source machine learning algorithm for analyzing impedimetric biosensor data using a mobile phone.
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Chi S, Kapoor A, Katz M, Rabin L. A-09Metamemory in Relation to Objective Episodic Memory Preclinical Dementia. Arch Clin Neuropsychol 2017. [DOI: 10.1093/arclin/acx076.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Macdonald AJ, Tremblay-Johnston YS, Grothe S, Chi S, Dosanjh P, Johnston S, Burke SA. Dispersing artifacts in FT-STS: a comparison of set point effects across acquisition modes. NANOTECHNOLOGY 2016; 27:414004. [PMID: 27607539 DOI: 10.1088/0957-4484/27/41/414004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Fourier-transform scanning tunnelling spectroscopy (FT-STS), or quasiparticle interference, has become an influential tool for the study of a wide range of important materials in condensed matter physics. However, FT-STS in complex materials is often challenging to interpret, requiring significant theoretical input in many cases, making it crucial to understand potential artifacts of the measurement. Here, we compare the most common modes of acquiring FT-STS data and show through both experiment and simulations that artifact features can arise that depend on how the tip height is stabilized throughout the course of the measurement. The most dramatic effect occurs when a series of dI/dV maps at different energies are acquired with simultaneous constant current feedback; here a feature that disperses in energy appears that is not observed in other measurement modes. Such artifact features are similar to those arising from real physical processes in the sample and are susceptible to misinterpretation.
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Chi S, Zivanovic S, Penfield MP. Application of Chitosan Films Enriched with Oregano Essential Oil on Bologna – Active Compounds and Sensory Attributes. FOOD SCI TECHNOL INT 2016. [DOI: 10.1177/1082013206063845] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Chitosan films prepared with oregano essential oil were applied on bologna slices. Release of the essential oil compounds during film preparation and application on the meat product and consumer acceptability of bologna enriched with oregano essential oil were tested. Oregano essential oil compounds were quantified by gas chromatography mass spectroscopy (GCMS) after extraction from the filmforming solution, films before and after application on bologna and from bologna slices before and after application of the films. The results indicated that the concentration of components of the essential oil sharply decreased during film preparation, e.g. from 757.7 ppm carvacrol in film-forming solution to 2.1 ppm in dried films. No carvacrol was detected in the films after application on bologna for 5 days at 4°C, mainly due to its diffusion into bologna. It seemed that the moisture and high lipid content of bologna helped the diffusion of the oregano essential oil from the chitosan film matrix into the product. Sensory evaluation suggested that addition of 45 ppm or less of oregano oil to bologna would be acceptable to consumers. Results support the potential use of chitosan–oregano essential oil films as an antimicrobial packaging material for processed meat.
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Bourgeois-Hope P, Chi S, Bonn DA, Liang R, Hardy WN, Wolf T, Meingast C, Doiron-Leyraud N, Taillefer L. Thermal Conductivity of the Iron-Based Superconductor FeSe: Nodeless Gap with a Strong Two-Band Character. PHYSICAL REVIEW LETTERS 2016; 117:097003. [PMID: 27610878 DOI: 10.1103/physrevlett.117.097003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Indexed: 06/06/2023]
Abstract
The thermal conductivity κ of the iron-based superconductor FeSe was measured at temperatures down to 75 mK in magnetic fields up to 17 T. In a zero magnetic field, the electronic residual linear term in the T=0 K limit, κ_{0}/T, is vanishingly small. The application of a magnetic field B causes an exponential increase in κ_{0}/T initially. Those two observations show that there are no zero-energy quasiparticles that carry heat and therefore no nodes in the superconducting gap of FeSe. The full field dependence of κ_{0}/T has the classic two-step shape of a two-band superconductor: a first rise at very low field, with a characteristic field B^{⋆}≪B_{c2}, and then a second rise up to the upper critical field B_{c2}. This shows that the superconducting gap is very small (but finite) on one of the pockets in the Fermi surface of FeSe. We estimate that the minimum value of the gap, Δ_{min}, is an order of magnitude smaller than the maximum value, Δ_{max}.
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Tsai Y, Yu P, Chang H, Chang C, Fu P, Lin C, Chiu Y, Chi S. SU-E-E-09: The Novel Investigation of the Accuracy of Image Position for Liver During Respiration in Helical CT. Med Phys 2015. [DOI: 10.1118/1.4923931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Lafay-Cousin L, Chi S, Smith A, Wells E, Madden J, Margol A, Ramaswamy V, Owen E, Strother D, Dhall G, Foreman N, Packer R, Bouffet E. MB-35 * VERY ENCOURAGING LONG-TERM SURVIVAL AND NEUROCOGNITIVE OUTCOME OF YOUNG CHILDREN TREATED FOR MEDULLOBLASTOMA WITH SEQUENTIAL HIGH DOSE CHEMOTHERAPY. Neuro Oncol 2015. [DOI: 10.1093/neuonc/nov061.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Durand AM, Belanger DP, Hamil TJ, Ye F, Chi S, Fernandez-Baca JA, Booth CH, Abdollahian Y, Bhat M. The unusual magnetism of nanoparticle LaCoO3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:176003. [PMID: 25872920 DOI: 10.1088/0953-8984/27/17/176003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Bulk and nanoparticle powders of LaCoO3 (LCO) were synthesized and their magnetic and structural properties were studied using SQUID magnetometry and neutron diffraction. The bulk and large nanoparticles exhibit weak ferromagnetism (FM) below T ≈ 85 K and a crossover from strong to weak antiferromagnetic (AFM) correlations near a transition expressed in the lattice parameters, To≈40 K. This crossover does not occur in the smallest nanoparticles; instead, the magnetic behavior is predominantly ferromagnetic. The amount of FM in the nanoparticles depends on the amount of Co3O4 impurity phase, which induces tensile strain on the LCO lattice. A core-interface model is introduced, with the core region exhibiting the AFM crossover and with FM in the interface region near surfaces and impurity phases.
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Lafay-Cousin L, Chi S, Smith A, Wells E, Madden J, Margol A, Ramaswamy V, Owen E, Strother D, Dhall G, Foreman N, Packer R, Bouffet E. PT-08 * VERY ENCOURAGING LONG TERM SURVIVAL AND NEUROCOGNITIVE OUTCOME OF YOUNG CHILDREN TREATED FOR MEDULLOBLASTOMA WITH SEQUENTIAL HIGH DOSE CHEMOTHERAPY. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou266.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mitamura H, Watanuki R, Kaneko K, Onozaki N, Amou Y, Kittaka S, Kobayashi R, Shimura Y, Yamamoto I, Suzuki K, Chi S, Sakakibara T. Spin-chirality-driven ferroelectricity on a perfect triangular lattice antiferromagnet. PHYSICAL REVIEW LETTERS 2014; 113:147202. [PMID: 25325654 DOI: 10.1103/physrevlett.113.147202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Indexed: 06/04/2023]
Abstract
Magnetic field (B) variation of the electrical polarization P(c) (∥c) of the perfect triangular lattice antiferromagnet RbFe(MoO(4))(2) is examined up to the saturation point of the magnetization for B⊥c. P(c) is observed only in phases for which chirality is predicted in the in-plane magnetic structures. No strong anomaly is observed in P(c) at the field at which the spin modulation along the c axis, and hence the spin helicity, exhibits a discontinuity to the commensurate state. These results indicate that the ferroelectricity in this compound originates predominantly from the spin chirality, the explanation of which would require a new mechanism for magnetoferroelectricity. The obtained field-temperature phase diagram of ferroelectricity agree well with those theoretically predicted for the spin chirality of a Heisenberg spin triangular lattice antiferromagnet.
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Kieran MW, Yao X, Macy M, Leary S, Cohen K, MacDonald T, Allen J, Boklan J, Smith A, Nazemi K, Gore L, Trippett T, DiRenzo J, Narendran A, Perentesis J, Prabhu S, Pinches N, Robison N, Manley P, Chi S. FINAL RESULTS OF A PROSPECTIVE MULTI-INSTITUTIONAL PHASE II STUDY OF EVEROLIMUS (RAD001), AN MTOR INHIBITOR, IN PEDIATRIC PATIENTS WITH RECURRENT OR PROGRESSIVE LOW-GRADE GLIOMA. A POETIC CONSORTIUM TRIAL. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou208.15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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