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PMC OpenAccess
Subject 경영,경제 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8111385/view Article Title Performance and onsite regeneration of natural zeolite for ammonium removal in a field-scale non-sewered sanitation systemAuthors C.J. Castro; H.Y. Shyu; L. Xaba; R. Bair; D.H. YehAbstract Natural zeolite clinoptilolite was used as the primary ammonium removal method from the permeate of an anaerobic membrane bioreactor (AnMBR) treating high-strength blackwater generated from a community toilet facility. This zeolite-based nutrient capture system (NCS) was a sub-component of a non-sewered sanitation system (NSSS) called the NEWgenerator and was field tested for 1.5 years at an informal settlement in South Africa. The NCS was operated for three consecutive loading cycles, each lasting 291, 110, and 52 days, respectively. Both blackwater (from toilets) and blackwater with yellow water (from toilets and urinals) were treated during the field trial. Over the three cycles, the NCS was able to remove 80 ± 28%, 64 ± 23%, and 94 ± 11%, respectively, of the influent ammonium. The addition of yellow water caused the rapid exhaustion of zeolite and the observed decrease of ammonium removal during Cycle 2. After Cycles 1 and 2, onsite regeneration was performed to recover the sorption capacity of the spent zeolite. The regenerant was comprised of NaCl under alkaline conditions and was operated as a recycle-batch to reduce the generation of regenerant waste. Modifications to the second regeneration process, including an increase in regenerant contact time from 15 to 30 h, improved the zeolite regeneration efficiency from 76 ± 0.7% to 96 ± 1.0%. The mass of recoverable ammonium in the regenerant was 2.63 kg NH4-N and 3.15 kg NH4-N after Regeneration 1 and 2, respectively. However, the mass of ammonium in the regenerant accounted for only 52.8% and 54.4% of the estimated NH4-N originally sorbed onto the zeolite beds after Cycles 1 and 2, respectively. The use of zeolite clinoptilolite is a feasible method for ammonium removal by NSSS that observe variable nitrogen loading rates, but further research is still needed to recover the nitrogen from the regenerant waste.Is Part Of The Science of the Total Environment 2021-07-01 , Vol.776 Identifier ISSN: 1879-1026, 0048-9697 DOI 10.1016/j.scitotenv.2021.145938Publisher ElsevierCategory Non-sewered sanitation; Zeolite; Ammonium; Wastewater; Resource recovery; SorptionLicense https://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). -
PMC OpenAccess
Subject 경영,경제 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8111332/view Article Title Modeling the potential impacts of climate change and adaptation strategies on groundnut production in IndiaAuthors M.D.M. Kadiyala; Swamikannu Nedumaran; Jyosthnaa Padmanabhan; Murali Krishna Gumma; Sridhar Gummadi; Srinivas Reddy Srigiri; Richard Robertson; Anthony WhitbreadAbstract Groundnut is one of the significant sources of oil, food, and fodder in India. It is grown in marginal arid and semi-arid agro-ecosystems with wide yield fluctuations due to spatial variability of rainfall and soil. Climate change, which is predicted to increase the intra- and inter-annual rainfall variability will further constrain the groundnut economy in India besides the global and domestic economic, social and policy changes. Through this study we aim to examine the biophysical and social economic impacts of climate change on groundnut production and prices to provide a comprehensive analysis of how agriculture and the food system will be affected. Using projected climate data for India, we estimated the biophysical impacts of climate change on groundnut during mid-century using representative concentration pathway (RCP 8.5) scenario. We examined the impacts of changes in population and income besides environmental factors on groundnut productivity. This is to highlight the importance of holistic assessment of biophysical and socioeconomic factors to better understand climate change impacts. Modelled projections show that by 2050, climate change under an optimistic scenario will result in −2.3 to 43.2% change in groundnut yields across various regions in India when climate alone was factored in. But the change in groundnut yields ranged from −0.9% to 16.2% when economic (population and income) and market variables (elasticities, trade, etc.) were also considered. Similarly, under pessimistic climate change scenario, the percent change in groundnut yields would be −33.7 to 3.4 with only the climate factored in and −11.2 to 4.3 with the additional economic and market variables included. This indicates the sensitivity of climate change impacts to differences in socioeconomic factors. This study highlights the need to take into account market effects to gain a holistic understanding of how economic and environmental factors impact agricultural food systems and economies.Is Part Of The Science of the Total Environment 2021-07-01 , Vol.776 Identifier ISSN: 1879-1026, 0048-9697 DOI 10.1016/j.scitotenv.2021.145996Publisher ElsevierCategory Groundnut; DSSAT; Climate change; Adaptation; Spatial modelingLicense https://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). -
PMC OpenAccess
Subject 경영,경제 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024944/view Article Title Ambient fine particulate matter in Latin American cities: Levels, population exposure, and associated urban factorsAuthors Nelson Gouveia; Josiah L. Kephart; Iryna Dronova; Leslie McClure; José Tapia Granados; Ricardo Morales Betancourt; Andrea Cortínez O'Ryan; José Luis Texcalac-Sangrador; Kevin Martinez-Folgar; Daniel Rodriguez; Ana V. Diez-RouxAbstract Background Exposure to particulate matter (PM2.5) is a major risk factor for morbidity and mortality. Yet few studies have examined patterns of population exposure and investigated the predictors of PM2.5 across the rapidly growing cities in lower- and middle-income countries. Objectives Characterize PM2.5 levels, describe patterns of population exposure, and investigate urban factors as predictors of PM2.5 levels. Methods We used data from the Salud Urbana en America Latina/Urban Health in Latin America (SALURBAL) study, a multi-country assessment of the determinants of urban health in Latin America, to characterize PM2.5 levels in 366 cities comprising over 100,000 residents using satellite-derived estimates. Factors related to urban form and transportation were explored. Results We found that about 172 million or 58% of the population studied lived in areas with air pollution levels above the defined WHO-AQG of 10 μg/m3 annual average. We also found that larger cities, cities with higher GDP, higher motorization rate and higher congestion tended to have higher PM2.5. In contrast cities with higher population density had lower levels of PM2.5. In addition, at the sub-city level, higher intersection density was associated with higher PM2.5 and more green space was associated with lower PM2.5. When all exposures were examined adjusted for each other, higher city per capita GDP and higher sub-city intersection density remained associated with higher PM2.5 levels, while higher city population density remained associated with lower levels. The presence of mass transit was also associated with lower PM2.5 after adjustment. The motorization rate also remained associated with PM2.5 and its inclusion attenuated the effect of population density. Discussion These results show that PM2.5 exposures remain a major health risk in Latin American cities and suggest that urban planning and transportation policies could have a major impact on ambient levels.Is Part Of The Science of the Total Environment 2021-06-10 , Vol.772 Identifier ISSN: 1879-1026, 0048-9697 DOI 10.1016/j.scitotenv.2021.145035Publisher ElsevierCategory Air pollution; Particulate matter; Built environment; City planningLicense This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). -
PMC OpenAccess
Subject 경영,경제, 인문사회과학 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175364/view Article Title Atomic scale symmetry and polar nanoclusters in the paraelectric phase of ferroelectric materialsAuthors Andreja Bencan; Emad Oveisi; Sina Hashemizadeh; Vignaswaran K. Veerapandiyan; Takuya Hoshina; Tadej Rojac; Marco Deluca; Goran Drazic; Dragan DamjanovicAbstract The nature of the “forbidden” local- and long-range polar order in nominally non-polar paraelectric phases of ferroelectric materials has been an open question since the discovery of ferroelectricity in oxide perovskites, ABO3. A currently considered model suggests locally correlated displacements of B-site atoms along a subset of <111> cubic directions. Such off-site displacements have been confirmed experimentally; however, being essentially dynamic in nature they cannot account for the static nature of the symmetry-forbidden polarization implied by the macroscopic experiments. Here, in an atomically resolved study by aberration-corrected scanning transmission electron microscopy complemented by Raman spectroscopy, we reveal, directly visualize and quantitatively describe static, 2–4 nm large polar nanoclusters in the nominally non-polar cubic phases of (Ba,Sr)TiO3 and BaTiO3. These results have implications on understanding of the atomic-scale structure of disordered materials, the origin of precursor states in ferroelectrics, and may help answering ambiguities on the dynamic-versus-static nature of nano-sized clusters.Is Part Of Nature Communications 2021-06-09 , Vol.12 Identifier ISSN: 2041-1723 DOI 10.1038/s41467-021-23600-3Publisher Nature Publishing Group UKCategory Ferroelectrics and multiferroics; Electronic devicesLicense https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. -
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Subject 경영,경제, 인문사회과학 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8173014/view Article Title Geometrically encoded SERS nanobarcodes for the logical detection of nasopharyngeal carcinoma-related progression biomarkersAuthors Duo Lin; Chang-Lin Hsieh; Keng-Chia Hsu; Pei-Hsuan Liao; Sufang Qiu; Tianxun Gong; Ken-Tye Yong; Shangyuan Feng; Kien Voon KongAbstract The limited availability of nasopharyngeal carcinoma-related progression biomarker array kits that offer physicians comprehensive information is disadvantageous for monitoring cancer progression. To develop a biomarker array kit, systematic identification and differentiation of a large number of distinct molecular surface-enhanced Raman scattering (SERS) reporters with high spectral temporal resolution is a major challenge. To address this unmet need, we use the chemistry of metal carbonyls to construct a series of unique SERS reporters with the potential to provide logical and highly multiplex information during testing. In this study, we report that geometric control over metal carbonyls on nanotags can produce 14 distinct barcodes that can be decoded unambiguously using commercial Raman spectroscopy. These metal carbonyl nanobarcodes are tested on human blood samples and show strong sensitivity (0.07 ng/mL limit of detection, average CV of 6.1% and >92% degree of recovery) and multiplexing capabilities for MMPs.Is Part Of Nature Communications 2021-06-08 , Vol.12 Identifier ISSN: 2041-1723 DOI 10.1038/s41467-021-23789-3Publisher Nature Publishing Group UKCategory Biosensors; Bioanalytical chemistry; BiochemistryLicense https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. -
PMC OpenAccess
Subject 경영,경제 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8085768/view Article Title Can transparency and accountability programs improve health? Experimental evidence from Indonesia and Tanzania☆Authors Jean Arkedis; Jessica Creighton; Akshay Dixit; Archon Fung; Stephen Kosack; Dan Levy; Courtney TolmieAbstract We assess the impact of a transparency and accountability program designed to improve maternal and newborn health (MNH) outcomes in Indonesia and Tanzania. Co-designed with local partner organizations to be community-led and non-prescriptive, the program sought to encourage community participation to address local barriers in access to high quality care for pregnant women and infants. We evaluate the impact of this program through randomized controlled trials (RCTs), involving 100 treatment and 100 control communities in each country. We find that on average, this program did not have a statistically significant impact on the use or content of maternal and newborn health services, nor on perceptions of civic efficacy or civic participation among recent mothers in the communities where it was offered. These findings hold in both countries and in a set of prespecified subgroups. To identify reasons for the lack of impacts, we use a mixed-method approach combining interviews, observations, surveys, focus groups, and ethnographic studies that together provide an in-depth assessment of the complex causal paths linking participation in the program to improvements in MNH outcomes. Although participation in program meetings was substantial and sustained in most communities, and most attempted at least some of what they had planned, only a minority achieved tangible improvements, and fewer still saw more than one such success. In our assessment, the main explanation for the lack of impact is that few communities were able to traverse the complex causal paths from planning actions to accomplishing tangible improvements in their access to quality health care.Is Part Of World Development 2021-06-01 , Vol.142 Identifier ISSN: 0305-750X DOI 10.1016/j.worlddev.2020.105369Publisher Pergamon PressCategory Transparency; Accountability; Community participation; Maternal and newborn health; Indonesia; TanzaniaLicense https://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). -
PMC OpenAccess
Subject 경영,경제 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024784/view Article Title The fall of the innovation empire and its possible rise through open scienceAuthors E. Richard GoldAbstract There is growing concern that the innovation system's ability to create wealth and attain social benefit is declining in effectiveness. This article explores the reasons for this decline and suggests a structure, the open science partnership, as one mechanism through which to slow down or reverse this decline. The article examines the empirical literature of the last century to document the decline. This literature suggests that the cost of research and innovation is increasing exponentially, that researcher productivity is declining, and, third, that these two phenomena have led to an overall flat or declining level of innovation productivity. The article then turns to three explanations for the decline – the growing complexity of science, a mismatch of incentives, and a balkanization of knowledge. Finally, the article explores the role that open science partnerships – public-private partnerships based on open access publications, open data and materials, and the avoidance of restrictive forms of intellectual property – can play in increasing the efficiency of the innovation system.Is Part Of Research Policy 2021-06-01 , Vol.50 (5) Identifier ISSN: 1873-7625, 0048-7333 DOI 10.1016/j.respol.2021.104226Publisher Elsevier, North-Holland Pub. CoCategory Innovation; Research productivity; Open science; Intellectual property; Patents; Research incentives; Public-private partnerships; NetworksLicense This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). -
PMC OpenAccess
Subject 경영,경제 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8085769/view Article Title Migration, labor and women’s empowerment: Evidence from an agricultural value chain in BangladeshAuthors Alan de Brauw; Berber Kramer; Mike MurphyAbstract As a substantial portion of the rural labor force migrates to urban areas, it is commonly assumed that women could take over traditionally male tasks in agricultural production, with potentially empowering outcomes for women. We study how changes in the supply of labor may influence female labor participation and empowerment outcomes. Using a detailed panel dataset on jute producers in the delta region of Bangladesh, we test whether out-migration of household members and perceived labor shortages are associated with the share of household and hired labor performed by women, and women’s empowerment. When a household experiences reduced household or hired labor supply, we observe a relatively larger use of female household labor, but a reduced share of female hired labor. We also find that reduced labor supply is not associated with significant reductions in gender wage gaps, or enhanced women’s empowerment. These findings suggest that given existing gender norms, male and female labor are not perfect substitutes for one another, and as a result, male outmigration is not associated with improved outcomes for women in cash crop production in the short run. Our results demonstrate a need for better understanding of the role of gender in rural labor markets, particularly in contexts of rapid urbanization.Is Part Of World Development 2021-06-01 , Vol.142 Identifier ISSN: 0305-750X DOI 10.1016/j.worlddev.2021.105445Publisher Pergamon PressCategory Rural; Labor; Agriculture; Migration; Gender; BangladeshLicense https://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). -
PMC OpenAccess
Subject 경영,경제, 인문사회과학 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8113234/view Article Title Community composition of microbial microcosms follows simple assembly rules at evolutionary timescalesAuthors Nittay Meroz; Nesli Tovi; Yael Sorokin; Jonathan FriedmanAbstract Managing and engineering microbial communities relies on the ability to predict their composition. While progress has been made on predicting compositions on short, ecological timescales, there is still little work aimed at predicting compositions on evolutionary timescales. Therefore, it is still unknown for how long communities typically remain stable after reaching ecological equilibrium, and how repeatable and predictable are changes when they occur. Here, we address this knowledge gap by tracking the composition of 87 two- and three-species bacterial communities, with 3–18 replicates each, for ~400 generations. We find that community composition typically changed during evolution, but that the composition of replicate communities remained similar. Furthermore, these changes were predictable in a bottom-up approach—changes in the composition of trios were consistent with those that occurred in pairs during coevolution. Our results demonstrate that simple assembly rules can hold even on evolutionary timescales, suggesting it may be possible to forecast the evolution of microbial communities.Is Part Of Nature Communications 2021-05-17 , Vol.12 Identifier ISSN: 2041-1723 DOI 10.1038/s41467-021-23247-0Publisher Nature Publishing Group UKCategory Evolutionary ecology; Coevolution; Experimental evolution; Microbial ecologyLicense https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. -
PMC OpenAccess
Subject 경영,경제, 인문사회과학 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8101336/view Article Title On-demand synthesis of phosphoramiditesAuthors Alexander F. Sandahl; Thuy J. D. Nguyen; Rikke A. Hansen; Martin B. Johansen; Troels Skrydstrup; Kurt V. GothelfAbstract Automated chemical synthesis of oligonucleotides is of fundamental importance for the production of primers for the polymerase chain reaction (PCR), for oligonucleotide-based drugs, and for numerous other medical and biotechnological applications. The highly optimised automised chemical oligonucleotide synthesis relies upon phosphoramidites as the phosphate precursors and one of the drawbacks of this technology is the poor bench stability of phosphoramidites. Here, we report on the development of an on-demand flow synthesis of phosphoramidites from their corresponding alcohols, which is accomplished with short reaction times, near-quantitative yields and without the need of purification before being submitted directly to automated oligonucleotide synthesis. Sterically hindered as well as redox unstable phosphoramidites are synthesised using this methodology and the subsequent couplings are near-quantitative for all substrates. The vision for this technology is direct integration into DNA synthesisers thereby omitting manual synthesis and storage of phosphoramidites.Is Part Of Nature Communications 2021-05-12 , Vol.12 Identifier ISSN: 2041-1723 DOI 10.1038/s41467-021-22945-zPublisher Nature Publishing Group UKCategory DNA; Synthetic chemistry methodology; Polymer synthesisLicense https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.