1
|
Elshaboury N, Hesham A, AlMetwaly WM. Optimal site selection for construction and demolition waste disposal using GIS-FAHP: a case study from Kafr El Sheikh City, Egypt. Environ Sci Pollut Res Int 2024; 31:8223-8239. [PMID: 38175518 DOI: 10.1007/s11356-023-31637-8] [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: 12/20/2022] [Accepted: 12/16/2023] [Indexed: 01/05/2024]
Abstract
The increasing number of building and demolition projects results in huge amounts of construction and demolition wastes (CDWs) that are illegally dumped. However, these wastes must be disposed of in appropriate legal sites to protect the environment and human health. After reviewing the literature, no prior research examined optimal site selection for dumping or recycling CDW in an Egyptian city. Furthermore, the absence of field surveys did not offer a holistic understanding of the specific criteria used in the model for this region, nor did it permit an assessment of the suitability of existing dumpsites, thereby revealing certain limitations in the final results. In this regard, this research aims to apply a multi-criteria geographic information system (GIS)-based framework to identify an optimal site for CDW disposal in Kafr El Sheikh City. The criteria affecting the site selection are identified and categorized from prior literature, which are further refined using field surveys and focus group to evaluate their applicability in the context of an Egyptian city. After conducting questionnaire surveys, the trapezoidal interval type II fuzzy analytic hierarchy process is applied to compute the weights of the identified criteria from the perspective of each group of experts. The entropy-based aggregation approach is employed to identify the compromise weights taking into account the preferences of different groups. GIS is a powerful tool for geoprocessing and analyzing spatial big data. The result is a scenario map for the optimal site locations with varying suitability scales (i.e., excellent, very good, good, average, poor, and very poor). The proposed methodology provides what-if scenarios based on a selected set of criteria. According to the results of the multi-criteria decision analysis models, the suitability varies based on the weights of the criteria. For the equal-weighted criteria model, the excellent category covers 5.96% of the study area, increasing to 6.48% for the weighted criteria model. These areas primarily lie in the northeast direction. Conversely, the majority of the study area, 41.80% under equal-weighted criteria and 32.39% under weighted criteria, falls within the average and poor suitability categories, respectively. In general, the most suitable areas are located on the outskirts of the city, and the suitability decreases near the central business district. To bridge the gap between research findings and practical applications, a land use analysis employing satellite imagery is conducted to pinpoint suitable locations for CDW disposal. Existing CDW dumpsites predominantly fall within the range of poor to very good for the equal-weighted criteria model, while the weighted criteria model categorizes them into the poor (16.66%) and average (83.33%) categories. The findings demonstrated the applicability of the proposed framework for CDW disposal management and planning.
Collapse
Affiliation(s)
- Nehal Elshaboury
- Construction and Project Management Research Institute, Housing and Building National Research Centre, Giza, Egypt.
| | - Amr Hesham
- Construction and Project Management Research Institute, Housing and Building National Research Centre, Giza, Egypt
- Construction Engineering Management Program, Arab Academy for Science, Technology & Maritime Transport, Giza, Egypt
| | - Wael M AlMetwaly
- Department of Geography and GIS, Faculty of African Postgraduate Studies, Cairo University, Giza, Egypt
- GIS Expert at General Organization of Physical Planning, Ministry of Housing, Utilities, and Urban Communities, Cairo, Egypt
| |
Collapse
|
2
|
Stelzer VB, da Silva AA, Penteado CSG, Cristale J. Organophosphate esters in inert landfill soil: A case study. Waste Manag Res 2023:734242X231190813. [PMID: 37638685 DOI: 10.1177/0734242x231190813] [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] [Indexed: 08/29/2023]
Abstract
Organophosphate esters (OPEs) used as flame retardants and plasticizers are additives in building and construction materials, decorations, furniture, electronic equipment, among other applications. The presence of materials containing these substances in construction and demolition waste (CDW) from weak waste management practices can result in environmental contamination. In this study, OPEs' presence in soil samples collected from a CDW landfill in Brazil was evaluated. Soil samples were collected in areas adjacent to CDW from an inert landfill, and the samples were analysed by gas chromatography coupled to mass spectrometry. The OPEs were detected in all soil samples at quantifiable concentrations ranging from 21 to 251 ng g-1, and detected compounds were tris(phenyl) phosphate, tris(2-butoxyethyl) phosphate, tris(1,3-dichloroisopropyl) phosphate, tris(2-chloroisopropyl) phosphate and 2-ethylhexyl diphenyl phosphate. The presence of these compounds in a CDW landfill is probably due to the lack of control of the materials sent to and deposited in the landfill, which, results in part from the lack of sampling and screening systems that can help identify the presence of contaminants in the CDW waste stream. This is partially due to OPEs not being considered controlled compounds under current regulations, thus screening or separation for handling of OPEs at construction and demolition work sites is rare to non-existent. The data generated in this study reveals the need for improving CDW management to minimize, if not eliminate, environmental contamination by OPEs.
Collapse
Affiliation(s)
| | | | | | - Joyce Cristale
- School of Technology, University of Campinas, Limeira, Sao Paulo, Brazil
- Center for Nuclear Energy in Agriculture, University of Sao Paulo, Piracicaba, Sao Paulo, Brazil
| |
Collapse
|
3
|
Jorge-Ortiz A, Braulio-Gonzalo M, Bovea MD. Exploring how waste management is being approached in green building rating systems: A case study. Waste Manag Res 2023; 41:1121-1133. [PMID: 36633151 DOI: 10.1177/0734242x221143952] [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] [Indexed: 05/16/2023]
Abstract
Green building rating systems (GBRS) propose sets of indicators to measure the level of sustainability of buildings, and include waste as one of the categories to be assessed. Yet, both the number of indicators and their aim, as well as the waste fraction they refer to, vary greatly from one system to another. This study identifies the waste-related indicators included in 10 global GBRS. They are classified on the basis of different criteria (waste fraction assessed, stages of the life cycle of the building, waste hierarchy and stages that make up the waste management system) so as to make it possible to subsequently analyse the importance given to each indicator through the specific weightings of each GBRS. Finally, the indicators are implemented in the case study of a building located in Colombia, in order to quantify the current level of sustainability achieved in the waste category of each system and to propose improvement actions that allow this score to be improved. In this way, it is shown that proper waste management can increase the level of sustainability of a building.
Collapse
Affiliation(s)
- Andrea Jorge-Ortiz
- Department of Mechanical Engineering and Construction, Universitat Jaume I, Castelló de la Plana, Spain
| | - Marta Braulio-Gonzalo
- Department of Mechanical Engineering and Construction, Universitat Jaume I, Castelló de la Plana, Spain
| | - María D Bovea
- Department of Mechanical Engineering and Construction, Universitat Jaume I, Castelló de la Plana, Spain
| |
Collapse
|
4
|
Galderisi A, Bravo M, Iezzi G, Cruciani G, Paris E, de Brito J. Physico-Mechanical Performances of Mortars Prepared with Sorted Earthquake Rubble: The Role of CDW Type and Contained Crystalline Phases. Materials (Basel) 2023; 16:2855. [PMID: 37049149 PMCID: PMC10096024 DOI: 10.3390/ma16072855] [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] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/29/2023] [Accepted: 03/29/2023] [Indexed: 06/19/2023]
Abstract
Construction and demolition waste (CDW) from earthquake rubbles was used here as recycled aggregates (RA) in cementitious binders. The materials were sorted in six groups: concrete (CO), natural stone (NS), tile (TI), brick (BR), perforated brick (PF) and roof tile (RT). The abundance (wt.%) of crystalline phases in each RA type was determined by X-ray Powder Diffraction (XRPD). Each group of RAs was used alone (100 wt.% of RA) and mixed with quartz-rich virgin aggregates (VA) to prepare 13 types of mortars (12 specimens per type): one reference mortar (RM) with only VA, six recycled aggregate mortars (RAM) and six recycled-plus-virgin aggregate mortars (RVAM). The physical and mechanical properties of aggregates and mortars reflect the type and abundance of crystalline phases in each CDW group. Recycled mortars rich in concrete, natural stones and tiles have better mechanical performance than mortars prepared with recycled bricks, perforated bricks and roof tiles. For each RA, RVAMs have superior mechanical characteristics than the corresponding RAM. Since the type and amount of phases contained in recycled aggregates strongly control the mechanical performance of new construction materials, they should be routinely quantified as reported here, in addition to other physical features (water absorption, density, etc.). The separation of heterogeneous CDW into homogeneous RA groups is necessary for the production of new construction materials with stable and predictable performances to ensure CDW recycling, especially in areas hit by major adverse events, where large amounts of still valuable materials could be used for reconstruction processes.
Collapse
Affiliation(s)
- Antonio Galderisi
- Dipartimento INGEO (Ingegneria & Geologia), Università di Chieti-Pescara ‘G. d’Annunzio’, 66100 Chieti, Italy
| | - Miguel Bravo
- CERIS, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Gianluca Iezzi
- Dipartimento INGEO (Ingegneria & Geologia), Università di Chieti-Pescara ‘G. d’Annunzio’, 66100 Chieti, Italy
- Istituto Nazionale di Geofisica e Vulcanologia—INGV, 00143 Rome, Italy
| | - Giuseppe Cruciani
- Dipartimento di Fisica e Scienze della Terra, Università di Ferrara, 44122 Ferrara, Italy
| | - Eleonora Paris
- Scuola di Scienze e Tecnologie, sez. Geologia, Università di Camerino, 62032 Camerino, Italy
| | - Jorge de Brito
- CERIS, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| |
Collapse
|
5
|
Kim H, Kim HJ, Kim H, Kim HR, Jo H, Hong J, Kim R, Kim JY, Ahn JS, Im YH, Lee SK, Kim H, Shin SY, Park YH. Real-World Data from a Refractory Triple-Negative Breast Cancer Cohort Selected Using a Clinical Data Warehouse Approach. Cancers (Basel) 2021; 13:5835. [PMID: 34830990 DOI: 10.3390/cancers13225835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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] [Received: 09/16/2021] [Revised: 11/12/2021] [Accepted: 11/18/2021] [Indexed: 12/02/2022] Open
Abstract
Simple Summary Patients with metastatic triple-negative breast cancer (mTNBC) have a very poor prognosis. We assume that some mTNBC patients have worse treatment outcomes and defined them as cases of refractory TNBC. We tried to investigate the characteristics and treatment outcomes of our refractory mTNBC cohort selected using a clinical data warehouse (CDW) approach. Between January 1997 and December 2019, TNBC patients were searched for in the breast cancer registry and, among them, pathologically confirmed mTNBC patients were selected as the study cohort (n = 451). Refractory TNBC was defined as cases of TNBC with confirmed distant metastasis within one year after adjuvant treatment. The refractory mTNBC group was younger and had a higher proportion of Ki-67 ≥ 3+ than the nonrefractory group. In addition, a much poorer prognosis existed among mTNBC patients, with an overall survival (OS) of 14.3 months and progression-free survival (PFS) of 4.2 months after first-line palliative chemotherapy compared to an OS of 24.8 months and PFS of 6.2 months in the nonrefractory TNBC group (p < 0.001). Abstract Purpose: Triple-negative breast cancer (TNBC) is well known for its aggressive course and poor prognosis. In this study, we sought to investigate clinical, demographic, and pathologic characteristics and treatment outcomes of patients with refractory, metastatic TNBC selected by a clinical data warehouse (CDW) approach. Patients and methods: Data were extracted from the real-time breast cancer registry integrated into the Data Analytics and Research Window for Integrated Knowledge C (DARWIN-C), the CDW of Samsung Medical Center. Between January 1997 and December 2019, a TNBC cohort was searched for in the breast cancer registry, which includes records from more than 40,000 patients. Among them, cases of pathologically confirmed metastatic TNBC (mTNBC) were selected as the cohort group (n = 451). The extracted data from the registry via the CDW platform included clinical, pathological, laboratory, and chemotherapy information. Refractory TNBC was defined as confirmed distant metastasis within one year after adjuvant treatment. Results: This study comprised a total of 451 patients with mTNBC, including 69 patients with de novo mTNBC, 131 patients in the nonrefractory TNBC group with confirmed stage IV disease after one year of adjuvant treatment, and 251 patients with refractory mTNBC, whose disease recurred as stage IV within one year after completing adjuvant treatment. The refractory mTNBC cohort was composed of patients with disease that recurred at stage IV after surgery (refractory mTNBC after surgery) (n = 207) and patients in whom metastasis was confirmed during neoadjuvant chemotherapy (unresectable TNBC due to progression during neoadjuvant chemotherapy) (n = 44). Patients in the refractory mTNBC group were younger than those in the nonrefractory group (median age 46 vs. 51 years; p < 0.001). Considering the pathological findings, the refractory group had a greater proportion of cases with Ki-67 ≥ 3+ than did the nonrefractory group (71% vs. 47%; p = 0.004). During a median 8.4 years of follow-up, the overall survival was 24.8 months in the nonrefractory mTNBC group and 14.3 months in the refractory mTNBC group (p < 0.001), and the median progression-free survival periods were 6.2 months and 4.2 months, respectively (p < 0.001). The median disease-free survival period was 30.1 months in the nonrefractory mTNBC group and only 7.6 months in the refractory mTNBC group. Factors related to metastatic sites affecting overall survival were liver metastasis at diagnosis (p < 0.001) and leptomeningeal involvement (p = 0.001). Conclusions: We revealed that patients with refractory mTNBC had a much poorer prognosis among all mTNBC cases and described the characteristics of this patient group.
Collapse
|
6
|
Xu Z, Yang H, Song X, Chen Y, Yang H, Liu M, Huang Z, Zhang Q, Sun J, Liu L, Wang Y. Topical review: recent progress of charge density waves in 2D transition metal dichalcogenide-based heterojunctions and their applications. Nanotechnology 2021; 32:492001. [PMID: 34450606 DOI: 10.1088/1361-6528/ac21ed] [Citation(s) in RCA: 4] [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] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Charge density wave (CDW) is an intriguing physical phenomenon especially found in two-dimensional (2D) layered systems such as transition-metal dichalcogenides (TMDs). The study of CDW is vital for understanding lattice modification, strongly correlated electronic behaviors, and other related physical properties. This paper gives a review of the recent studies on CDW emerging in 2D TMDs. First, a brief introduction and the main mechanisms of CDW are given. Second, the interplay between CDW patterns and the related unique electronic phenomena (superconductivity, spin, and Mottness) is elucidated. Then various manipulation methods such as doping, applying strain, local voltage pulse to induce the CDW change are discussed. Finally, examples of the potential application of devices based on CDW materials are given. We also discuss the current challenge and opportunities at the frontier in this research field.
Collapse
Affiliation(s)
- Ziqiang Xu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Huixia Yang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Xuan Song
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Yaoyao Chen
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Han Yang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Meng Liu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Zeping Huang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Quanzhen Zhang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Jiatao Sun
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Liwei Liu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| | - Yeliang Wang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, People's Republic of China
| |
Collapse
|
7
|
Altvater MA, Tilak N, Rao S, Li G, Won CJ, Cheong SW, Andrei EY. Charge Density Wave Vortex Lattice Observed in Graphene-Passivated 1T-TaS 2 by Ambient Scanning Tunneling Microscopy. Nano Lett 2021; 21:6132-6138. [PMID: 34231367 DOI: 10.1021/acs.nanolett.1c01655] [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] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The nearly commensurate charge density wave (CDW) excitations native to the transition-metal dichalcogenide crystal, 1T-TaS2, under ambient conditions are revealed by scanning tunneling microscopy (STM) and spectroscopy (STS) measurements of a graphene/TaS2 heterostructure. Surface potential measurements show that the graphene passivation layer prevents oxidation of the air-sensitive 1T-TaS2 surface. The graphene protective layer does not however interfere with probing the native electronic properties of 1T-TaS2 by STM/STS, which revealed that nearly commensurate CDW hosts an array of vortex-like topological defects. We find that these topological defects organize themselves to form a lattice with quasi-long-range order, analogous to the vortex Bragg glass in type-II superconductors but accessible in ambient conditions.
Collapse
Affiliation(s)
- Michael A Altvater
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Nikhil Tilak
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Skandaprasad Rao
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Guohong Li
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| | - Choong-Jae Won
- Laboratory for Pohang Emergent Materials, Pohang Accelerator Laboratory and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Sang-Wook Cheong
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
- Laboratory for Pohang Emergent Materials, Pohang Accelerator Laboratory and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
- Center for Quantum Materials Synthesis, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Eva Y Andrei
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, United States
| |
Collapse
|
8
|
Iodice S, Garbarino E, Cerreta M, Tonini D. Sustainability assessment of Construction and Demolition Waste management applied to an Italian case. Waste Manag 2021; 128:83-98. [PMID: 33975139 PMCID: PMC8183595 DOI: 10.1016/j.wasman.2021.04.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 12/01/2020] [Revised: 03/24/2021] [Accepted: 04/11/2021] [Indexed: 05/17/2023]
Abstract
Construction and Demolition Waste represents a priority stream for the European Union and has a large potential for closing the material circulation loop in line with the Circular Economy principles. The present study focuses on the socio-economic and environmental implications of the management of such waste in the Campania Region (Italy), with the aim of documenting the benefits of recycling actions and landfill avoidance. By using local primary data, and complementing them with data from literature and datasets, three scenarios have been investigated: i) Status Quo, i.e., a baseline scenario presenting the current management of Construction and Demolition Waste in the Region; ii) a Linear Economy scenario, considering the total flow disposed of in landfill and iii) a Best Practice scenario based on the implementation of selective demolition practices and increased recycling for the production of high-quality recycled aggregates. Special attention has been paid to the land use and socio-economic implications linked to the management of this flow, which are rarely considered. We quantify that, with the implementation of best practices, ca. 18 Mkg CO2 -eq. can be saved annually relative to the Status Quo alongside creating additional 1,000 jobs-eq. and incurring important benefits on land use. The results stress that the potential environmental and social benefits of selective demolition and best practices are significant, but the incurred economic costs may hinder their application and the resulting development of more circular economy actions in the construction sector, highlighting the need for incentives and tools to facilitate this transition.
Collapse
Affiliation(s)
- Silvia Iodice
- European Commission, Joint Research Centre (JRC), Ispra, Italy; University of Naples Federico II, Department of Architecture, Naples, Italy.
| | - Elena Garbarino
- European Commission, Joint Research Centre (JRC), Seville, Spain
| | - Maria Cerreta
- University of Naples Federico II, Department of Architecture, Naples, Italy
| | - Davide Tonini
- European Commission, Joint Research Centre (JRC), Seville, Spain
| |
Collapse
|
9
|
Dhond R, Acher R, Leatherman S, Page S, Sanford R, Elbers D, Meng F, Ferguson R, Brophy MT, Do NV. Rapid implementation of a modular clinical trial informatics solution for COVID-19 research. Inform Med Unlocked 2021; 27:100788. [PMID: 34786452 PMCID: PMC8588694 DOI: 10.1016/j.imu.2021.100788] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/01/2021] [Accepted: 11/11/2021] [Indexed: 01/31/2023] Open
Abstract
Veterans Health Administration (VHA) services are most frequently used by patients 65 years and older, an age group that is disproportionally affected by COVID-19. Here we describe a modular Clinical Trial Informatics Solution (CTIS) that was rapidly developed and deployed to support a multi-hospital embedded pragmatic clinical trial in COVID-19 patients within the VHA. Our CTIS includes tools for patient eligibility screening, informed consent tracking, treatment randomization, EHR data transformation for reporting and interfaces for patient outcome and adverse event tracking. We hope our CTIS component descriptions and practical lessons learned will serve as a useful building block for others creating their own clinical trial tools and have made application and database code publicly available.
Collapse
Affiliation(s)
- Rupali Dhond
- VA Boston Healthcare System, Boston, MA, USA,Boston University School of Medicine, Boston, MA, USA,Corresponding author. VA Boston Healthcare System, 150 S Huntington Ave, Boston, MA, 02130, USA
| | - Ryan Acher
- VA Boston Healthcare System, Boston, MA, USA
| | | | - Sarah Page
- VA Boston Healthcare System, Boston, MA, USA
| | | | - Danne Elbers
- VA Boston Healthcare System, Boston, MA, USA,University of Vermont, Burlington, VT, USA
| | - Frank Meng
- VA Boston Healthcare System, Boston, MA, USA,Boston University School of Medicine, Boston, MA, USA
| | | | - Mary T. Brophy
- VA Boston Healthcare System, Boston, MA, USA,Boston University School of Medicine, Boston, MA, USA
| | - Nhan V. Do
- VA Boston Healthcare System, Boston, MA, USA,Boston University School of Medicine, Boston, MA, USA
| |
Collapse
|
10
|
Lim S, Kim J, Won C, Cheong SW. Atomic-Scale Observation of Topological Vortices in the Incommensurate Charge Density Wave of 2H-TaSe 2. Nano Lett 2020; 20:4801-4808. [PMID: 32496066 DOI: 10.1021/acs.nanolett.0c00539] [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] [Indexed: 06/11/2023]
Abstract
It has been only recently realized that topological vortices associated with structural distortions or ordered spins are rather common in numerous materials where long-range interactions are not dominant. Incommensurate modulations that frequently occur in charge density wave (CDW) materials are often understood in terms of discommensurations with a periodic phase shift. The accumulation of a one-dimensional (1D) phase shift can result in, for example, CDW dislocations in 2H-TaSe2 with incommensurate CDW (I-CDW). Since any atomic-scale experimental investigation of CDW dislocations in 2H-TaSe2 has been lacking, we have performed the atomic-scale observation of 2H-TaSe2 with I-CDW, stabilized with Pd intercalation or strain, with scanning probe microscopy, and unveiled the existence of topological Z6 or Z4 vortices with topologically protected 2D winding movements of atomic displacement vectors. The discovery opens the ubiquitous nature of topological vortex domains and a new avenue to explore new facets of various incommensurate modulations or discommensurations.
Collapse
Affiliation(s)
- Seongjoon Lim
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Piscataway, New Jersey 08854, United States
| | - Jaewook Kim
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Piscataway, New Jersey 08854, United States
| | - Choongjae Won
- Laboratory for Pohang Emergent Materials, Pohang Accelerator Laboratory and Max Plank POSTECH/KOREA Research Initiative, Pohang University of Science and Technology, Pohang 37673, Korea
| | - Sang-Wook Cheong
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Piscataway, New Jersey 08854, United States
- Laboratory for Pohang Emergent Materials, Pohang Accelerator Laboratory and Max Plank POSTECH/KOREA Research Initiative, Pohang University of Science and Technology, Pohang 37673, Korea
| |
Collapse
|
11
|
Roque S, Maia Pederneiras C, Brazão Farinha C, de Brito J, Veiga R. Concrete-Based and Mixed Waste Aggregates in Rendering Mortars. Materials (Basel) 2020; 13:ma13081976. [PMID: 32340288 PMCID: PMC7254318 DOI: 10.3390/ma13081976] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/08/2020] [Accepted: 04/21/2020] [Indexed: 11/17/2022]
Abstract
This paper presents a study of incorporation of two types of construction and demolition waste (CDW) in rendering mortars, as aggregates at 0%, 20%, 50% and 100% (by volume). Recycled concrete aggregate (RCA) and mixed recycled aggregate (MRA) were used. The former is mainly composed of cementitious waste and the latter consists of a mixture of non-segregated wastes. The performance of the cement mortars with recycled aggregates was evaluated through an extensive experimental programme. The analysis comprised workability, mechanical strength, water absorption, shrinkage, open porosity and the evaluation of durability by permeability to water under pressure after an artificial accelerated ageing test. The results are considered positive, although as the incorporation of recycled aggregates (both MRA and RCA) increased the mechanical strength, the modulus of elasticity and bulk density decreased, which leads to the production of lighter mortars that are less susceptible to cracking. The modified mortar with 20% of MRA presented the best performance, in terms of mechanical behaviour.
Collapse
Affiliation(s)
- Samuel Roque
- Civil Engineering Research and Innovation for Sustainability (CERIS), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1-1049-001 Lisbon, Portugal; (S.R.); (C.M.P.); (C.B.F.)
| | - Cinthia Maia Pederneiras
- Civil Engineering Research and Innovation for Sustainability (CERIS), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1-1049-001 Lisbon, Portugal; (S.R.); (C.M.P.); (C.B.F.)
- National Laboratory for Civil Engineering, Av. do Brasil 101, 1700-066 Lisbon, Portugal;
| | - Catarina Brazão Farinha
- Civil Engineering Research and Innovation for Sustainability (CERIS), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1-1049-001 Lisbon, Portugal; (S.R.); (C.M.P.); (C.B.F.)
- National Laboratory for Civil Engineering, Av. do Brasil 101, 1700-066 Lisbon, Portugal;
| | - Jorge de Brito
- Civil Engineering Research and Innovation for Sustainability (CERIS), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1-1049-001 Lisbon, Portugal; (S.R.); (C.M.P.); (C.B.F.)
- Correspondence:
| | - Rosário Veiga
- National Laboratory for Civil Engineering, Av. do Brasil 101, 1700-066 Lisbon, Portugal;
| |
Collapse
|
12
|
Wang H, She H, Xu J, Liang L. A Three-Point Hyperbolic Combination Model for the Settlement Prediction of Subgrade Filled with Construction and Demolition Waste. Materials (Basel) 2020; 13:ma13081959. [PMID: 32331250 PMCID: PMC7216158 DOI: 10.3390/ma13081959] [Citation(s) in RCA: 2] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 11/16/2022]
Abstract
Using construction and demolition waste (CDW) as road subgrade filling materials is an excellent way to solve the disparity between increased demand and road construction aggregate shortages. However, a key quality control problem is predicting the subgrade settlement, primarily because the CDW subgrade settlement prediction methods are not yet mature. To go some way in overcoming this problem, in this paper we developed a three-point hyperbolic combination model to predict CDW subgrade settlement, in which three appropriate points for the measured settlement curve were selected in the prediction samples to improve the hyperbolic model. Then, common prediction models—namely, the hyperbolic model, the three-point model, and the Hushino model—were compared with the proposed combination model to assess its viability. Finally, the three-point hyperbolic combination prediction accuracy was analyzed for different start points t0 and time intervals Δt. The analyses found that the proposed model was in good agreement with the measured data, had a high correlation coefficient, and had only small errors. However, the time interval Δt needed to be greater than 80 days and the start point t0 needed to be selected at the beginning of the stable post-filling period, that is, t0 = 90–100 days. The application parameters were also determined to provide a reference for the large-scale application and settlement predictions of CDW subgrade.
Collapse
Affiliation(s)
- Haiying Wang
- School of Construction Machinery, Chang’an University, Xi’an 710064, China; (H.S.); (L.L.)
- Correspondence:
| | - Hui She
- School of Construction Machinery, Chang’an University, Xi’an 710064, China; (H.S.); (L.L.)
| | - Jian Xu
- School of Management, Xi’an University Science and Technology, Xi’an 710054, China;
| | - Linhao Liang
- School of Construction Machinery, Chang’an University, Xi’an 710064, China; (H.S.); (L.L.)
| |
Collapse
|
13
|
Gao Y, Yin Y, Li B, He K, Wang X. Post-failure behavior analysis of the Shenzhen "12.20" CDW landfill landslide. Waste Manag 2019; 83:171-183. [PMID: 30514464 DOI: 10.1016/j.wasman.2018.11.015] [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: 01/03/2018] [Revised: 08/28/2018] [Accepted: 11/09/2018] [Indexed: 06/09/2023]
Abstract
Since the 1990s, with rapid economic development and urbanization occurring in many countries, the amount of construction and demolition waste (CDW) has also increased. Landfills have become the most commonly used method of disposing of CDW. The safety of landfill slopes is very important. On December 20, 2015, a catastrophic landslide occurred in Shenzhen, Guangdong, Southeastern China. Seventy-seven people were killed, and 33 buildings were buried or damaged. In this paper, the Shenzhen 12.20 landslide is used as an example, and the characteristics of the landfill landslide's post-failure behavior are studied. The following conclusions are made: (1) According to our field investigations, the landslide's motion can be divided into the source area, the propagation area, and the accumulation area. During post-failure motion, loose saturated spoil, which experiences motion similar to that of a slurry flow, and water are the critical factors that cause slope failure and result in a long runout slide. (2) The DAN3D analysis method can satisfactorily reproduce the motion of the Shenzhen "12.20" landslide. (3) A Frictional model can be used for the simulation analysis of the source area. In addition, the Bingham model can be used for the fluidization simulation analysis of the propagation and accumulation areas of a CDW landslide. These conclusions can be used for scientific analysis of CDW landfill landslide hazard zoning and early monitoring and warnings.
Collapse
Affiliation(s)
- Yang Gao
- Key Laboratory of Shale Gas and Geoengineering, Institute of Geology and Geophysics, Chinese Academy of Sciences, China; Institute of GeoMechanics, Chinese Academy of GeoSciences, CGS, China
| | - Yueping Yin
- China Institute of Geo-Environment Monitoring, CGS, China
| | - Bin Li
- Institute of GeoMechanics, Chinese Academy of GeoSciences, CGS, China.
| | - Kai He
- Institute of GeoMechanics, Chinese Academy of GeoSciences, CGS, China
| | - Xueliang Wang
- Key Laboratory of Shale Gas and Geoengineering, Institute of Geology and Geophysics, Chinese Academy of Sciences, China
| |
Collapse
|
14
|
Chen J, Su Y, Si H, Chen J. Managerial Areas of Construction and Demolition Waste: A Scientometric Review. Int J Environ Res Public Health 2018; 15:E2350. [PMID: 30356018 PMCID: PMC6266467 DOI: 10.3390/ijerph15112350] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 10/17/2018] [Accepted: 10/22/2018] [Indexed: 11/23/2022]
Abstract
In past decades, the massive generation of construction and demolition waste (CDW) was increasingly threatening the public environment and humanity health worldwide. A large amount of research has been devoted to the CDW from difference perspectives. However, few scholars have attempted to summarize and review the extant studies, especially in the managerial areas of CDW (MA-CDW). This paper fills this gap via a systematic and quantitative review in the CDW management field. Employing the scientometric analysis method, a total of 261 articles published from 2006 to 2018 were collected to construct the knowledge map and comprehensive framework for MA-CDW. Results show that the overall evolutionary trend of MA-CDW was from basic management concepts to internal and external challenges analysis, to organizational strategy and innovative management practices. The major MA-CDW knowledge domains were identified and summarized into four pillars, namely: (1) factor and challenge; (2) composition and quantification; (3) assessment and comparison; and (4) technology and method. Based on the trend, knowledge gaps and future research directions were found out and discussed. This study contributes to the existing MA-CDW knowledge by presenting a comprehensive knowledge framework. Furthermore, these findings can provide the researchers and practitioners with an in-depth understanding for the sustainable governance of CDW.
Collapse
Affiliation(s)
- Jianguo Chen
- School of Economics and Management, Tongji University, Shanghai 200092, China.
| | - Yangyue Su
- School of Economics and Management, Tongji University, Shanghai 200092, China.
| | - Hongyun Si
- School of Economics and Management, Tongji University, Shanghai 200092, China.
| | - Jindao Chen
- School of Economics and Management, Tongji University, Shanghai 200092, China.
| |
Collapse
|
15
|
Ryu H, Chen Y, Kim H, Tsai HZ, Tang S, Jiang J, Liou F, Kahn S, Jia C, Omrani AA, Shim JH, Hussain Z, Shen ZX, Kim K, Min BI, Hwang C, Crommie MF, Mo SK. Persistent Charge-Density-Wave Order in Single-Layer TaSe 2. Nano Lett 2018; 18:689-694. [PMID: 29300484 DOI: 10.1021/acs.nanolett.7b03264] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We present the electronic characterization of single-layer 1H-TaSe2 grown by molecular beam epitaxy using a combined angle-resolved photoemission spectroscopy, scanning tunneling microscopy/spectroscopy, and density functional theory calculations. We demonstrate that 3 × 3 charge-density-wave (CDW) order persists despite distinct changes in the low energy electronic structure highlighted by the reduction in the number of bands crossing the Fermi energy and the corresponding modification of Fermi surface topology. Enhanced spin-orbit coupling and lattice distortion in the single-layer play a crucial role in the formation of CDW order. Our findings provide a deeper understanding of the nature of CDW order in the two-dimensional limit.
Collapse
Affiliation(s)
- Hyejin Ryu
- Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
- Max Planck POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology , Pohang 37673, Korea
| | - Yi Chen
- Department of Physics, University of California , Berkeley, California 94720, United States
| | - Heejung Kim
- Department of Physics, Pohang University of Science and Technology , Pohang 37673, Korea
| | - Hsin-Zon Tsai
- Department of Physics, University of California , Berkeley, California 94720, United States
| | - Shujie Tang
- Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
| | - Juan Jiang
- Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Franklin Liou
- Department of Physics, University of California , Berkeley, California 94720, United States
| | - Salman Kahn
- Department of Physics, University of California , Berkeley, California 94720, United States
| | - Caihong Jia
- Department of Physics, University of California , Berkeley, California 94720, United States
- Henan Key Laboratory of Photovoltaic Materials and Laboratory of Low-dimensional Materials Science, Henan University , Kaifeng 475004, People's Republic of China
| | - Arash A Omrani
- Department of Physics, University of California , Berkeley, California 94720, United States
| | - Ji Hoon Shim
- Department of Physics, Pohang University of Science and Technology , Pohang 37673, Korea
- Department of Chemistry and Division of Advanced Nuclear Engineering, Pohang University of Science and Technology , Pohang 37673, Korea
| | - Zahid Hussain
- Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Zhi-Xun Shen
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
- Geballe Laboratory for Advanced Materials, Departments of Physics and Applied Physics, Stanford University , Stanford, California 94305, United States
| | - Kyoo Kim
- Max Planck POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology , Pohang 37673, Korea
- Department of Physics, Pohang University of Science and Technology , Pohang 37673, Korea
| | - Byung Il Min
- Department of Physics, Pohang University of Science and Technology , Pohang 37673, Korea
| | - Choongyu Hwang
- Department of Physics, Pusan National University , Busan 46241, Korea
| | - Michael F Crommie
- Department of Physics, University of California , Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
- Kavli Energy Nano Sciences Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Sung-Kwan Mo
- Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| |
Collapse
|
16
|
Hase I, Yanagisawa T, Kawashima K. One Way to Design a Valence-Skip Compound. Nanoscale Res Lett 2017; 12:127. [PMID: 28235362 PMCID: PMC5315650 DOI: 10.1186/s11671-017-1897-z] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 02/03/2017] [Indexed: 06/06/2023]
Abstract
Valence-skip compound is a good candidate with high T c and low anisotropy because it has a large attractive interaction at the site of valence-skip atom. However, it is not easy to synthesize such compound because of (i) the instability of the skipping valence state, (ii) the competing charge order, and (iii) that formal valence may not be true in some compounds. In the present study, we show several examples of the valence-skip compounds and discuss how we can design them by first principles calculations. Furthermore, we calculated the electronic structure of a promising candidate of valence skipping compound RbTlCl3 from first principles. We confirmed that the charge-density wave (CDW) is formed in this compound, and the Tl atoms in two crystallographic different sites take the valence Tl1+ and Tl3+. Structure optimization study reveals that this CDW is stable at the ambient pressure, while this CDW gap can be collapsed when we apply pressure with several gigapascals. In this metallic phase, we can expect a large charge fluctuation and a large electron-phonon interaction.
Collapse
Affiliation(s)
- I. Hase
- National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 2, Umezono 1-1-4, Tsukuba, Ibaraki 305-8568 Japan
| | - T. Yanagisawa
- National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 2, Umezono 1-1-4, Tsukuba, Ibaraki 305-8568 Japan
| | - K. Kawashima
- IMRA Material R&D Co., Ltd., Kariya, Aichi 448-0032 Japan
| |
Collapse
|
17
|
Bovea MD, Powell JC. Developments in life cycle assessment applied to evaluate the environmental performance of construction and demolition wastes. Waste Manag 2016; 50:151-172. [PMID: 26919970 DOI: 10.1016/j.wasman.2016.01.036] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [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: 09/03/2015] [Revised: 12/23/2015] [Accepted: 01/28/2016] [Indexed: 06/05/2023]
Abstract
This paper provides a review of the literature that applies the life cycle assessment (LCA) methodology to the assessment of the environmental performance of the life cycle of construction and demolition waste (CDW) management systems. This article is focused on generating a general mapping of the literature and on identifying the best practices in compliance with LCA framework and proposing directions for future LCA studies in this field. The temporal evolution of the research in this field and the aim of the studies have grown in parallel with the legal framework related to waste and energy efficiency of buildings. Most studies have been published in Europe, followed by USA. Asia and Australia, being at an incipient application stage to the rest of the world. Topics related to "LCA of buildings, including their EoL" and "LCA of general CDW management strategies" are the most frequently analysed, followed by "LCA of EoL of construction elements" and "LCA of natural material vs recycled material". Regarding the strategies, recycling off-site and incineration, both combined with landfill for the rejected fractions, are the most commonly applied. Re-use or recycling on-site is the strategy least applied. The key aspect when LCA is applied to evaluate CDW management systems is the need to normalise which processes to include in the system boundary and the functional unit, the use of inventory data adapted to the context of the case study and the definition of a common set of appropriate impact assessment categories. Also, it is important to obtain results disaggregated by unit processes. This will allow the comparison between case studies.
Collapse
Affiliation(s)
- M D Bovea
- Departament of Mechanical Engineering & Construction, Universitat Jaume I, Castellón, Spain.
| | - J C Powell
- CSERGE, School of Environmental Sciences, University of East Anglia, Norwich NR4 7 TJ, UK
| |
Collapse
|
18
|
Rodríguez-Robles D, García-González J, Juan-Valdés A, Morán-Del Pozo JM, Guerra-Romero MI. Overview regarding construction and demolition waste in Spain. Environ Technol 2014; 36:3060-3070. [PMID: 25230145 DOI: 10.1080/09593330.2014.957247] [Citation(s) in RCA: 6] [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] [Indexed: 06/03/2023]
Abstract
The construction sector comprises a number of activities that may result in environmental impacts of considerable magnitude, waste generation being one of the major negative effects of this industry due to the large streams generated. Proper knowledge of the environmental problem caused by the sector is of great importance in order to achieve an effective waste management. Thus, this paper analyse the Spanish situation regarding construction and demolition waste (CDW) compared with other European Union countries; which sets out the current figures of the CDW scenario (legislation, generation, composition, treatment and market) as well as the difficulties encountered when handling this residue.
Collapse
Affiliation(s)
| | - Julia García-González
- a Department of Engineering and Agricultural Sciences , University of Leon , Leon , Spain
| | - Andrés Juan-Valdés
- a Department of Engineering and Agricultural Sciences , University of Leon , Leon , Spain
| | - Julia M Morán-Del Pozo
- a Department of Engineering and Agricultural Sciences , University of Leon , Leon , Spain
| | | |
Collapse
|
19
|
Sittijunda S, Tomás AF, Reungsang A, O-thong S, Angelidaki I. Ethanol production from glucose and xylose by immobilized Thermoanaerobacter pentosaceus at 70 °C in an up-flow anaerobic sludge blanket (UASB) reactor. Bioresour Technol 2013; 143:598-607. [PMID: 23845708 DOI: 10.1016/j.biortech.2013.06.056] [Citation(s) in RCA: 4] [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: 03/27/2013] [Revised: 06/11/2013] [Accepted: 06/14/2013] [Indexed: 06/02/2023]
Abstract
The newly isolated extreme thermophilic ethanologen Thermoanaerobacter pentosaceus was immobilized in different support materials in order to improve its ethanol production ability. In batch fermentation, a maximum ethanol yield of 1.36 mol mol(-1) consumed sugars was obtained by T. pentosaceus immobilized on rapeseed straw. Additionally, immobilized T. pentosaceus' ethanol production was improved by 11% in comparison to free cells. In continuous mode, it was shown that hydraulic retention time (HRT) affected ethanol yield, and a dramatic shift from ethanol to acetate and lactate production occurred at an HRT of 6 h. The maximum ethanol yield and concentration, 1.50 mol mol(-1) consumed sugars and 12.4 g l(-1), were obtained with an HRT of 12 h. The latter represented an improvement of 60% in relation to previously obtained results. This indicates that immobilization of T. pentosaceus is an effective strategy to improve its ethanol production ability.
Collapse
Affiliation(s)
- Sureewan Sittijunda
- Department of Environmental Engineering, Technical University of Denmark, 113 Miljoevej, 2800 Kongens Lyngby, Denmark
| | | | | | | | | |
Collapse
|
20
|
Dulermo T, Tréton B, Beopoulos A, Kabran Gnankon AP, Haddouche R, Nicaud JM. Characterization of the two intracellular lipases of Y. lipolytica encoded by TGL3 and TGL4 genes: new insights into the role of intracellular lipases and lipid body organisation. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1486-95. [PMID: 23856343 DOI: 10.1016/j.bbalip.2013.07.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 11/23/2022]
Abstract
Eukaryotes store lipids in a specialised organelle, the lipid body (LB), mainly as triglycerides (TAGs). Both the rates of synthesis and degradation contribute to the control of the accumulation of TAGs. The synthesis of TAGs in yeasts has been well documented, especially in the model yeast Saccharomyces cerevisiae and in the oleaginous yeast Yarrowia lipolytica. However, descriptions of the processes involved in TAG degradation are more scarce and mostly for S. cerevisiae. Here, we report the characterisation of two Y. lipolytica genes, YlTGL3 and YlTGL4, encoding intracellular lipases involved in TAG degradation. The two proteins are localised in lipid bodies, and YlTgl4 was mainly found at the interface between LBs. Surprisingly, the spatial organisation of YlTgl3 and YlTgl4 depends on the culture medium and on the physiological phase of the cell. Inactivation of one or both genes doubles the lipid accumulation capacity of Y. lipolytica, increasing the cell's capacity to accumulate TAGs. The amino acid sequence of YlTgl4 contains the consensus sequence motif (G/A)XSXG, typical of serine hydrolases, whereas YlTgl3 does not. Single and double mutants are unable to degrade TAGs, and higher expression of YlTgl4 correlates with TAG degradation. Therefore, we propose that YlTgl4 is the main lipase responsible for TAG degradation and that YlTgl3 may act as a positive regulator of YlTgl4 rather than a functional lipase. Thus, contrary to S. cerevisiae, Y. lipolytica possesses two intracellular lipases with distinct roles and with distinct localisations in the LB.
Collapse
|