V. Chellappa, Angelin Lincy Gunasekaran, Kalaimani Ramakrishnan
The factor influencing waste generation in the Indian construction industry has been examined in previous studies, along with the most significant factors generating waste. However, no study has answered the question: do different stakeholders have similar concerns? This study aimed to identify the significant factors generating waste from the multi-stakeholder's perspectives. The factors generating construction waste were identified through a comprehensive literature analysis. A total of 36 construction waste-generating factors were identified and clustered into six different groups: design and drawing (DED), procurement and handling (PHL), construction methods and planning (CMP), human resources (HR), site condition (SC), and external (EX). A questionnaire survey was conducted to gather multi-stakeholder's viewpoints (designers, owners, and contractors) and was ranked based on the relative importance index (RII). The most significant factors indicated by all the groups were frequent design change, poor attitude and behavior of workers, ineffective planning and scheduling, and poor control and supervision. The findings could assist in facilitating waste management strategies to be more effective and focused. Overall, the study findings are expected to identify new patterns of cooperation among different stakeholders.
{"title":"Factors influencing construction waste generation: perspectives from India","authors":"V. Chellappa, Angelin Lincy Gunasekaran, Kalaimani Ramakrishnan","doi":"10.1680/jwarm.23.00006","DOIUrl":"https://doi.org/10.1680/jwarm.23.00006","url":null,"abstract":"The factor influencing waste generation in the Indian construction industry has been examined in previous studies, along with the most significant factors generating waste. However, no study has answered the question: do different stakeholders have similar concerns? This study aimed to identify the significant factors generating waste from the multi-stakeholder's perspectives. The factors generating construction waste were identified through a comprehensive literature analysis. A total of 36 construction waste-generating factors were identified and clustered into six different groups: design and drawing (DED), procurement and handling (PHL), construction methods and planning (CMP), human resources (HR), site condition (SC), and external (EX). A questionnaire survey was conducted to gather multi-stakeholder's viewpoints (designers, owners, and contractors) and was ranked based on the relative importance index (RII). The most significant factors indicated by all the groups were frequent design change, poor attitude and behavior of workers, ineffective planning and scheduling, and poor control and supervision. The findings could assist in facilitating waste management strategies to be more effective and focused. Overall, the study findings are expected to identify new patterns of cooperation among different stakeholders.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74199143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1680/jwarm.2023.176.3.94
C. Chroni
{"title":"Editorial: Embracing the circular economy – revolutionising construction through waste utilisation for improved material quality and performance","authors":"C. Chroni","doi":"10.1680/jwarm.2023.176.3.94","DOIUrl":"https://doi.org/10.1680/jwarm.2023.176.3.94","url":null,"abstract":"","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"58 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73661228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study evaluated characteristics of mortars using recycled construction and demolition waste (CDW) from the industry as fine recycled aggregate in replacement of natural sand (NS). Mixes with replacements in volume of 20 and 100% CDW and a control mix with just NS were tested for their compressive and flexural strength and alkali–silica reactivity (ASR). For mechanical strength, experimental results showed satisfactory performance for 20% CDW content. Concerning the ASR test, mortars with CDW performed better than the control, demonstrating a general innocuous behaviour for ASR. Scanning electron microscopy and energy-dispersive X-ray analysis were performed on aggregate and mortar samples before and after the ASR test and confirmed the results, demonstrating that the attack was more severe in the samples with the greatest amount of siliceous material in the aggregate. The results demonstrate the viability of the use of CDW fine aggregate replacement in mortars, envisaging the possibility of its incorporation in concrete.
{"title":"Influence of recycled fines on strength and alkali–silica reactivity in cement composites","authors":"Natália Salamoni, Gustavo Toigo, Joana Sousa-Coutinho","doi":"10.1680/jwarm.22.00002","DOIUrl":"https://doi.org/10.1680/jwarm.22.00002","url":null,"abstract":"This study evaluated characteristics of mortars using recycled construction and demolition waste (CDW) from the industry as fine recycled aggregate in replacement of natural sand (NS). Mixes with replacements in volume of 20 and 100% CDW and a control mix with just NS were tested for their compressive and flexural strength and alkali–silica reactivity (ASR). For mechanical strength, experimental results showed satisfactory performance for 20% CDW content. Concerning the ASR test, mortars with CDW performed better than the control, demonstrating a general innocuous behaviour for ASR. Scanning electron microscopy and energy-dispersive X-ray analysis were performed on aggregate and mortar samples before and after the ASR test and confirmed the results, demonstrating that the attack was more severe in the samples with the greatest amount of siliceous material in the aggregate. The results demonstrate the viability of the use of CDW fine aggregate replacement in mortars, envisaging the possibility of its incorporation in concrete.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136261098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Spent Mushroom Compost (SMC) already broken down into smaller particles by fungal action is an ideal material for producing biogas. Two cycles of five Solid State Anaerobic Digesters (SS-ADs) with different mix-ratio of SMC and Switchgrass (SG) were operated at feedstock-to-effluent ratio (F/E) of 2 at a temperature 35±2°C. The total solids concentration of the digester was kept at ∼17%. Initial biogas production observed during the start-up of the digester confirmed the presence of readily available extractives for digestion. In the first cycle, the highest methane yield was observed in SMC 0 (0% SMC + 100% SG) of 28.82 L/kg VS/d and the lowest yield was observed in SMC 4 (100% SMC + 0% SG) as 10.32 L/kg VS/d. The substrate containing 100% SG (SMC 0) recorded the highest cumulative biogas yield of 295.43 L/kg VS in 63 days. The digesters with higher SMC fraction showed lower methane production, low pH value, and high VFA content upon decomposition. The SS-ADs having SMC/SG of 50:50 showed more than 2 times methane production in comparison with SS-ADs having SMC as sole substrate. An estimation of volumetric productivity also established a linear relationship with the SMC/SG ratio.
{"title":"Co-digestion of mushroom compost with switchgrass using solid–state anaerobic digester","authors":"R. Nair, A. Thalla, V. V. Nair","doi":"10.1680/jwarm.22.00009","DOIUrl":"https://doi.org/10.1680/jwarm.22.00009","url":null,"abstract":"Spent Mushroom Compost (SMC) already broken down into smaller particles by fungal action is an ideal material for producing biogas. Two cycles of five Solid State Anaerobic Digesters (SS-ADs) with different mix-ratio of SMC and Switchgrass (SG) were operated at feedstock-to-effluent ratio (F/E) of 2 at a temperature 35±2°C. The total solids concentration of the digester was kept at ∼17%. Initial biogas production observed during the start-up of the digester confirmed the presence of readily available extractives for digestion. In the first cycle, the highest methane yield was observed in SMC 0 (0% SMC + 100% SG) of 28.82 L/kg VS/d and the lowest yield was observed in SMC 4 (100% SMC + 0% SG) as 10.32 L/kg VS/d. The substrate containing 100% SG (SMC 0) recorded the highest cumulative biogas yield of 295.43 L/kg VS in 63 days. The digesters with higher SMC fraction showed lower methane production, low pH value, and high VFA content upon decomposition. The SS-ADs having SMC/SG of 50:50 showed more than 2 times methane production in comparison with SS-ADs having SMC as sole substrate. An estimation of volumetric productivity also established a linear relationship with the SMC/SG ratio.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"35 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75064913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-01DOI: 10.1680/jwarm.2023.176.2.30
L. Y. Ng, R. Tan, D. Ng
{"title":"Editorial: Sustainable waste management via material recovery and energy production","authors":"L. Y. Ng, R. Tan, D. Ng","doi":"10.1680/jwarm.2023.176.2.30","DOIUrl":"https://doi.org/10.1680/jwarm.2023.176.2.30","url":null,"abstract":"","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"34 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81713726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A sustainable approach to the small-scale treatment of portable toilet and septic tank waste is in need in order to minimize the associated public health and environmental risks. Treatment of human wastes is highly regulated by legislation in many countries given the high content of organic components and pathogens. In conventional wastewater treatment plants (WWTP), sewage undergoes a series of treatment stages (primary, secondary and tertiary) before effluent discharge. Delivering this approach at a small scale, to meet demands of temporary events, public gatherings or remote locations provides benefits in reducing transport and bulk handling. For a small-scale treatment process to effectively work the process steps need to be simplified and minimized. We review the potential of a new treatment scheme where the first step is the solid-liquid fraction separation, followed by the anaerobic digestion of the solid fraction including energy recovery in a combined heat and power (CHP) unit. The liquid fraction undergoes a series of filtration and disinfection steps to comply with effluent regulations. Digestate from anaerobic digestion is burned on site to provide local domestic/office heating. This approach has a great potential for application in different locations where inputs may be sporadic, such as outdoor festivals, disaster response scenarios and construction sites.
{"title":"Treatment of human waste in small-scale facilities: a prospective review","authors":"C. Rodriguez, A. Hursthouse, Z. El-Hassan","doi":"10.1680/jwarm.22.00017","DOIUrl":"https://doi.org/10.1680/jwarm.22.00017","url":null,"abstract":"A sustainable approach to the small-scale treatment of portable toilet and septic tank waste is in need in order to minimize the associated public health and environmental risks. Treatment of human wastes is highly regulated by legislation in many countries given the high content of organic components and pathogens. In conventional wastewater treatment plants (WWTP), sewage undergoes a series of treatment stages (primary, secondary and tertiary) before effluent discharge. Delivering this approach at a small scale, to meet demands of temporary events, public gatherings or remote locations provides benefits in reducing transport and bulk handling. For a small-scale treatment process to effectively work the process steps need to be simplified and minimized. We review the potential of a new treatment scheme where the first step is the solid-liquid fraction separation, followed by the anaerobic digestion of the solid fraction including energy recovery in a combined heat and power (CHP) unit. The liquid fraction undergoes a series of filtration and disinfection steps to comply with effluent regulations. Digestate from anaerobic digestion is burned on site to provide local domestic/office heating. This approach has a great potential for application in different locations where inputs may be sporadic, such as outdoor festivals, disaster response scenarios and construction sites.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"45 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90489004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is significant to use recycled waste plastic bags in concrete to solve the issue of the disposal of leftover polyethylene in the environment. This research incorporated the plastic bags’ polyethylene into concrete and evaluated the mechanical properties of concrete, to reduce cracking to some extent and increase the tensile & flexural strengths and deformation capacity. Six mixtures were used with varying percentages of waste plastic bags (i.e., 0%, 0.3%, 0.6%, 0.9%, 1.2%, and 1.5%). The sorptivity test was conducted following ASTM C1585 and the volume of permeable voids test was according to the ASTM C642 requirements. The pullout strength of the steel rebar in a concrete cylinder was also determined. With waste polyethylene, it was noted that the flexural strength increased, pull-out bond strength declined and initial sorptivity increased. This decline in the volume of permeable voids was due to the heterogeneity of the mixture which leads to the low density of the mixture due to waste plastic bags. Experiments proved that substituting plastic bags for fine aggregates in concrete, increases flexural and split tensile strengths while decreasing compressive and pullout strength.
{"title":"Investigating the potential of waste polyethylene in concrete","authors":"Hammad Ghafoor, S. Abbas, S. Shahid, Shahid Ali","doi":"10.1680/jwarm.22.00028","DOIUrl":"https://doi.org/10.1680/jwarm.22.00028","url":null,"abstract":"It is significant to use recycled waste plastic bags in concrete to solve the issue of the disposal of leftover polyethylene in the environment. This research incorporated the plastic bags’ polyethylene into concrete and evaluated the mechanical properties of concrete, to reduce cracking to some extent and increase the tensile & flexural strengths and deformation capacity. Six mixtures were used with varying percentages of waste plastic bags (i.e., 0%, 0.3%, 0.6%, 0.9%, 1.2%, and 1.5%). The sorptivity test was conducted following ASTM C1585 and the volume of permeable voids test was according to the ASTM C642 requirements. The pullout strength of the steel rebar in a concrete cylinder was also determined. With waste polyethylene, it was noted that the flexural strength increased, pull-out bond strength declined and initial sorptivity increased. This decline in the volume of permeable voids was due to the heterogeneity of the mixture which leads to the low density of the mixture due to waste plastic bags. Experiments proved that substituting plastic bags for fine aggregates in concrete, increases flexural and split tensile strengths while decreasing compressive and pullout strength.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"6 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76304963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Sapsford, D. I. Stewart, Dannielle E. Sinnett, I. Burke, P. Cleall, M. Harbottle, W. Mayes, N. Owen, A. Sardo, A. Weightman
Many countries face serious strategic challenges with the future supply of both aggregates and critical elements. Yet, at the same time, they must sustainably manage continued multimillion tonne annual arisings of mineral-dominated wastes from mining and industry. In an antithesis of Circular Economy principles, these wastes continue to be landfilled despite often comprising valuable components, such as critical metals, soil macronutrients and mineral components which sequester atmospheric CO2. In this paper, the authors aim to introduce a new concept for value recovery from mineral-rich wastes where materials are temporarily stored and cleaned in landfill-like repositories designed to be mined later. The time in storage is utilised for remediating contaminated materials and separating and concentrating valuable components. It is proposed that this could be achieved through engineering the repository to accelerate “lithomimetic” processes, i.e. those mimicking natural supergene processes responsible for the formation of secondary ores. This paper summarises the concept and justifications and outlines fundamental aspects of how this new concept might be applied to the design of future repositories. The proposed concept aims to end the current “linear” landfilling of mineral-rich wastes in favour of reuse as aggregates and ores.
{"title":"Circular economy landfills for temporary storage and treatment of mineral-rich wastes","authors":"D. Sapsford, D. I. Stewart, Dannielle E. Sinnett, I. Burke, P. Cleall, M. Harbottle, W. Mayes, N. Owen, A. Sardo, A. Weightman","doi":"10.1680/jwarm.22.00008","DOIUrl":"https://doi.org/10.1680/jwarm.22.00008","url":null,"abstract":"Many countries face serious strategic challenges with the future supply of both aggregates and critical elements. Yet, at the same time, they must sustainably manage continued multimillion tonne annual arisings of mineral-dominated wastes from mining and industry. In an antithesis of Circular Economy principles, these wastes continue to be landfilled despite often comprising valuable components, such as critical metals, soil macronutrients and mineral components which sequester atmospheric CO2. In this paper, the authors aim to introduce a new concept for value recovery from mineral-rich wastes where materials are temporarily stored and cleaned in landfill-like repositories designed to be mined later. The time in storage is utilised for remediating contaminated materials and separating and concentrating valuable components. It is proposed that this could be achieved through engineering the repository to accelerate “lithomimetic” processes, i.e. those mimicking natural supergene processes responsible for the formation of secondary ores. This paper summarises the concept and justifications and outlines fundamental aspects of how this new concept might be applied to the design of future repositories. The proposed concept aims to end the current “linear” landfilling of mineral-rich wastes in favour of reuse as aggregates and ores.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"33 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82641546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Construction and demolition waste constitutes the largest municipal solid waste (MSW) globally with environmental concerns. However, waste management is not considered a priority objective in construction compared to time and cost. Therefore, construction practitioners’ waste management priority is evaluated in this study. A review of the literature revealed waste management attributes from multiple perspectives. A questionnaire survey was adopted to solicit practitioners’ contributions on their importance. Then, the attributes were prioritised and categorised into high, medium and low priorities using the Voting Analytical Hierarchy Process (VAHP). Empirical results indicate that the high priority materials procurement attributes were alliance with suppliers, a take-back clause in suppliers’ agreement document, accurate material quantification, accurate material ordering, and just-in-time delivery (JIT) plan. Senior managers’ early commitment to waste minimisation, effective communication among project participants, making subcontractors responsible for their waste, identifying recyclable materials and identifying reusable materials were high-priority attributes for managing waste in the construction stage. The findings of this study indicate areas where contractors should focus effort to improve waste management in the industry by collaborating with subcontractors and suppliers. Future studies should focus on developing frameworks that provide actionable means for implementing waste management attributes identified in this research.
{"title":"Prioritising critical attributes for the management of materials procurement and construction waste","authors":"C. Chidiobi, C. Booth, J. Lamond","doi":"10.1680/jwarm.22.00013","DOIUrl":"https://doi.org/10.1680/jwarm.22.00013","url":null,"abstract":"Construction and demolition waste constitutes the largest municipal solid waste (MSW) globally with environmental concerns. However, waste management is not considered a priority objective in construction compared to time and cost. Therefore, construction practitioners’ waste management priority is evaluated in this study. A review of the literature revealed waste management attributes from multiple perspectives. A questionnaire survey was adopted to solicit practitioners’ contributions on their importance. Then, the attributes were prioritised and categorised into high, medium and low priorities using the Voting Analytical Hierarchy Process (VAHP). Empirical results indicate that the high priority materials procurement attributes were alliance with suppliers, a take-back clause in suppliers’ agreement document, accurate material quantification, accurate material ordering, and just-in-time delivery (JIT) plan. Senior managers’ early commitment to waste minimisation, effective communication among project participants, making subcontractors responsible for their waste, identifying recyclable materials and identifying reusable materials were high-priority attributes for managing waste in the construction stage. The findings of this study indicate areas where contractors should focus effort to improve waste management in the industry by collaborating with subcontractors and suppliers. Future studies should focus on developing frameworks that provide actionable means for implementing waste management attributes identified in this research.","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"336 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76896765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.1680/jwarm.2023.176.1.1
M. Promentilla
{"title":"Editorial: Our future begins here and now","authors":"M. Promentilla","doi":"10.1680/jwarm.2023.176.1.1","DOIUrl":"https://doi.org/10.1680/jwarm.2023.176.1.1","url":null,"abstract":"","PeriodicalId":45077,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Waste and Resource Management","volume":"267 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80696021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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