Pub Date : 2025-10-11DOI: 10.1016/j.jdeveco.2025.103656
Caio Pedro Castro , Raphael Corbi
We examine the short-term impact of income shocks on mortality in Brazil using administrative data and the quasi-random timing of disbursements from a federal wage allowance program for low-income workers. Exploiting variation in payment timing by birth month and a sharp eligibility cutoff, we find that mortality increases by 9.5% during the week of payment, particularly for deaths related to economic activity such as cardiovascular conditions and external causes. Effects are strongest in areas with low financial development and poor healthcare access, suggesting that limited consumption smoothing and delayed medical care amplify mortality risks. Our findings highlight how institutional constraints in developing countries shape the health consequences of predictable income transfers, with implications for the design and timing of social protection programs.
{"title":"Income shocks and mortality of low-wage workers: Evidence from wage allowances in Brazil","authors":"Caio Pedro Castro , Raphael Corbi","doi":"10.1016/j.jdeveco.2025.103656","DOIUrl":"10.1016/j.jdeveco.2025.103656","url":null,"abstract":"<div><div>We examine the short-term impact of income shocks on mortality in Brazil using administrative data and the quasi-random timing of disbursements from a federal wage allowance program for low-income workers. Exploiting variation in payment timing by birth month and a sharp eligibility cutoff, we find that mortality increases by 9.5% during the week of payment, particularly for deaths related to economic activity such as cardiovascular conditions and external causes. Effects are strongest in areas with low financial development and poor healthcare access, suggesting that limited consumption smoothing and delayed medical care amplify mortality risks. Our findings highlight how institutional constraints in developing countries shape the health consequences of predictable income transfers, with implications for the design and timing of social protection programs.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103656"},"PeriodicalIF":4.6,"publicationDate":"2025-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-10DOI: 10.1016/j.jdeveco.2025.103660
Leandro S. Carvalho , Joana Cardim , Pedro Carneiro , Damien de Walque
One way to advance our understanding of individual differences in decision-making is to study the development of children's decision-making. This paper studies the causal effects of daycare attendance on children's economic preferences and decision-making abilities, exploiting a lottery system that randomized admissions into oversubscribed daycare centers in Rio de Janeiro. Impacts are estimated separately for boys and girls. Daycare attendance increased the decision-making quality of boys by 0.16 standard deviations (SD) and the aversion of girls to disadvantageous inequality (i.e., having less than one's peer) by 0.23 SD. It also decreased the self-control of boys by 0.19 SD.
{"title":"The decision-makers we become: Early education and the decision-making of boys and girls","authors":"Leandro S. Carvalho , Joana Cardim , Pedro Carneiro , Damien de Walque","doi":"10.1016/j.jdeveco.2025.103660","DOIUrl":"10.1016/j.jdeveco.2025.103660","url":null,"abstract":"<div><div>One way to advance our understanding of individual differences in decision-making is to study the development of children's decision-making. This paper studies the causal effects of daycare attendance on children's economic preferences and decision-making abilities, exploiting a lottery system that randomized admissions into oversubscribed daycare centers in Rio de Janeiro. Impacts are estimated separately for boys and girls. Daycare attendance increased the decision-making quality of boys by 0.16 standard deviations (SD) and the aversion of girls to disadvantageous inequality (i.e., having less than one's peer) by 0.23 SD. It also decreased the self-control of boys by 0.19 SD.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103660"},"PeriodicalIF":4.6,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145362572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-10DOI: 10.1016/j.jdeveco.2025.103657
Dean Karlan , Matt Lowe , Robert Osei , Isaac Osei-Akoto , Benjamin N. Roth , Christopher Udry
We randomized mobile money transfers to a sample of low-income Ghanaians during the COVID-19 pandemic. Treated households received eight transfers that sum to roughly one month’s income, while control households only received one transfer. The mere announcement of upcoming transfers has no effect. Once disbursed, transfers increase contemporaneous food expenditure by 8% and income by 20%, but do not affect psychological well-being. Over 40% of the transfers are spent on food. We find suggestive evidence that transfers increased social distancing. The positive effect on income does not persist to two years after the last transfer, and surprisingly, two-year effects on consumption and psychological well-being are negative. Together, we learn that pandemic-era cash transfers can support households economically without diminishing adherence to public health protocols, though with null or negative long-term effects.
{"title":"Social protection and social distancing during the pandemic: Mobile money transfers in Ghana","authors":"Dean Karlan , Matt Lowe , Robert Osei , Isaac Osei-Akoto , Benjamin N. Roth , Christopher Udry","doi":"10.1016/j.jdeveco.2025.103657","DOIUrl":"10.1016/j.jdeveco.2025.103657","url":null,"abstract":"<div><div>We randomized mobile money transfers to a sample of low-income Ghanaians during the COVID-19 pandemic. Treated households received eight transfers that sum to roughly one month’s income, while control households only received one transfer. The mere announcement of upcoming transfers has no effect. Once disbursed, transfers increase contemporaneous food expenditure by 8% and income by 20%, but do not affect psychological well-being. Over 40% of the transfers are spent on food. We find suggestive evidence that transfers increased social distancing. The positive effect on income does not persist to two years after the last transfer, and surprisingly, two-year effects on consumption and psychological well-being are negative. Together, we learn that pandemic-era cash transfers can support households economically without diminishing adherence to public health protocols, though with null or negative long-term effects.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103657"},"PeriodicalIF":4.6,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We investigate whether teachers hold systematically biased expectations about students based on caste identity, using data from a large, detailed, and representative survey of public schools in Bihar, India. Students take standardized tests that determine their actual academic rank, while teachers independently rate each student’s relative standing within the class. The gap between a student’s actual rank and their teacher’s perceived rating gives us a measure of the teacher’s Evaluation Bias. Using a teacher fixed-effect approach, we find that forward caste teachers systematically underestimate the performance of backward caste students compared to forward caste peers taught in the same class. These caste-based differences in Evaluation Bias remain robust to alternative definitions of backward caste status and different measures of students’ performance.
{"title":"Caste identity and teachers’ biased expectations: Evidence from Bihar, India","authors":"Ritwik Banerjee , Satarupa Mitra , Soham Sahoo , Ashmita Gupta","doi":"10.1016/j.jdeveco.2025.103650","DOIUrl":"10.1016/j.jdeveco.2025.103650","url":null,"abstract":"<div><div>We investigate whether teachers hold systematically biased expectations about students based on caste identity, using data from a large, detailed, and representative survey of public schools in Bihar, India. Students take standardized tests that determine their actual academic rank, while teachers independently rate each student’s relative standing within the class. The gap between a student’s actual rank and their teacher’s perceived rating gives us a measure of the teacher’s <em>Evaluation Bias</em>. Using a teacher fixed-effect approach, we find that forward caste teachers systematically underestimate the performance of backward caste students compared to forward caste peers taught in the same class. These caste-based differences in <em>Evaluation Bias</em> remain robust to alternative definitions of backward caste status and different measures of students’ performance.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103650"},"PeriodicalIF":4.6,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-09DOI: 10.1016/j.jdeveco.2025.103668
Binlei Gong , Haoyang Li , Liguo Lin , Hanxiang Ling , Wei Sun
This paper exploits China’s Water Quality Control Assessment Plan as a natural experiment to examine the impact of environmental regulation on fertilizer use and food security. Leveraging variation in enforcement incentives across counties determined by their locations relative to water quality monitoring stations, we document a 5.9 % fertilizer application reduction in upstream counties, driven by reduction in public financial support for agriculture. Salience of information highlighting agriculture as a major pollution source reinforces enforcement incentives in curbing fertilizer use. Agricultural output remained stable, reflecting both prior overuse of fertilizer and slight productivity gains likely associated with improved water quality.
{"title":"Two birds, one stone: Responses of agriculture to water pollution regulation","authors":"Binlei Gong , Haoyang Li , Liguo Lin , Hanxiang Ling , Wei Sun","doi":"10.1016/j.jdeveco.2025.103668","DOIUrl":"10.1016/j.jdeveco.2025.103668","url":null,"abstract":"<div><div>This paper exploits China’s Water Quality Control Assessment Plan as a natural experiment to examine the impact of environmental regulation on fertilizer use and food security. Leveraging variation in enforcement incentives across counties determined by their locations relative to water quality monitoring stations, we document a 5.9 % fertilizer application reduction in upstream counties, driven by reduction in public financial support for agriculture. Salience of information highlighting agriculture as a major pollution source reinforces enforcement incentives in curbing fertilizer use. Agricultural output remained stable, reflecting both prior overuse of fertilizer and slight productivity gains likely associated with improved water quality.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103668"},"PeriodicalIF":4.6,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-08DOI: 10.1016/j.jdeveco.2025.103649
Seiro Ito , Abu S. Shonchoy
Rural families in developing countries often face a critical trade-off: keeping children in school or involving them in seasonal agricultural labor. Misaligned school calendars intensify this challenge, significantly increasing school dropout rates. Leveraging the timing of Ramadan school holidays as a natural experiment, we find that annual exams coinciding with the harvest season increase school dropout rates by 6.6 to 9.0 percentage points (from the base of 25% dropout) among children from agricultural households in Bangladesh. This effect is predominantly driven by boys who participate in peak seasonal agricultural activities. Our findings are robust to varying age cut-offs and definitions of agricultural households. Long-term analyses employing age-specific cohorts using national household surveys corroborate these results. Complementary evidence from India, exploiting state-level academic calendar variations, further supports the findings. This study underscores the importance of carefully designing school calendars in rural areas that align with local agricultural seasonality.
{"title":"Seasonality, academic calendar and school dropouts in South Asia","authors":"Seiro Ito , Abu S. Shonchoy","doi":"10.1016/j.jdeveco.2025.103649","DOIUrl":"10.1016/j.jdeveco.2025.103649","url":null,"abstract":"<div><div>Rural families in developing countries often face a critical trade-off: keeping children in school or involving them in seasonal agricultural labor. Misaligned school calendars intensify this challenge, significantly increasing school dropout rates. Leveraging the timing of Ramadan school holidays as a natural experiment, we find that annual exams coinciding with the harvest season increase school dropout rates by 6.6 to 9.0 percentage points (from the base of 25% dropout) among children from agricultural households in Bangladesh. This effect is predominantly driven by boys who participate in peak seasonal agricultural activities. Our findings are robust to varying age cut-offs and definitions of agricultural households. Long-term analyses employing age-specific cohorts using national household surveys corroborate these results. Complementary evidence from India, exploiting state-level academic calendar variations, further supports the findings. This study underscores the importance of carefully designing school calendars in rural areas that align with local agricultural seasonality.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103649"},"PeriodicalIF":4.6,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-08DOI: 10.1016/j.jdeveco.2025.103651
Jeanet Sinding Bentzen , Nina Boberg-Fazlic , Paul Sharp , Christian Volmar Skovsgaard , Christian Vedel
Did religious missions influence firm-level productivity? This study examines the impact of the Inner Mission (IM) movement on productivity in early twentieth-century Denmark, a predominantly Protestant and homogeneous society undergoing rapid industrialization. Using data on 964 creameries and employing an instrumental variables approach, we provide evidence that IM intensity reduced productivity in butter production, measured by the Milk-to-Butter ratio. The main mechanisms were Sunday closures, which disrupted economies of scale, and the fragmentation of creameries due to doctrinal disagreements among farmers. These disruptions prevented creameries from operating efficiently and reduced their profitability. Our results show how religiosity shaped patterns of modernization and industrial development absent the usual colonial or missionary confounders. This historical case speaks to debates in development economics about how informal institutions and moral regulation can constrain firm behavior and productivity.
{"title":"Holy cows and spilled milk: The impact of religious missions on firm-level productivity","authors":"Jeanet Sinding Bentzen , Nina Boberg-Fazlic , Paul Sharp , Christian Volmar Skovsgaard , Christian Vedel","doi":"10.1016/j.jdeveco.2025.103651","DOIUrl":"10.1016/j.jdeveco.2025.103651","url":null,"abstract":"<div><div>Did religious missions influence firm-level productivity? This study examines the impact of the Inner Mission (IM) movement on productivity in early twentieth-century Denmark, a predominantly Protestant and homogeneous society undergoing rapid industrialization. Using data on 964 creameries and employing an instrumental variables approach, we provide evidence that IM intensity reduced productivity in butter production, measured by the Milk-to-Butter ratio. The main mechanisms were Sunday closures, which disrupted economies of scale, and the fragmentation of creameries due to doctrinal disagreements among farmers. These disruptions prevented creameries from operating efficiently and reduced their profitability. Our results show how religiosity shaped patterns of modernization and industrial development absent the usual colonial or missionary confounders. This historical case speaks to debates in development economics about how informal institutions and moral regulation can constrain firm behavior and productivity.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103651"},"PeriodicalIF":4.6,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145363007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
While existing evidence shows that nation-building policies unify societies, little is known about how and what makes some societal groups to resist them. We examine this in the context of the post-Mexican Revolution (1920s–1950s), when the new state implemented a nation-building policy to eliminate Indigenous cultures and identities by increasing connectivity via transport infrastructure. In a difference-in-differences design, we leverage heterogeneity in the exposure to pre-colonial political centralisation as a proxy for the ability of Indigenous populations in mobilising to resist national integration. We find that the expansion of transport infrastructure was lower in municipalities with a stronger efficacy of Indigenous mobilisation. We demonstrate that this underprovision of public goods can be partly explained by Indigenous identity preservation and high abilities for collective actions.
{"title":"Public good or public bad? Nation-building and Indigenous institutions","authors":"Aldo Elizalde , Eduardo Hidalgo , Nayeli Salgado , Sotiris Kampanelis","doi":"10.1016/j.jdeveco.2025.103652","DOIUrl":"10.1016/j.jdeveco.2025.103652","url":null,"abstract":"<div><div>While existing evidence shows that nation-building policies unify societies, little is known about how and what makes some societal groups to resist them. We examine this in the context of the post-Mexican Revolution (1920s–1950s), when the new state implemented a nation-building policy to eliminate Indigenous cultures and identities by increasing connectivity via transport infrastructure. In a difference-in-differences design, we leverage heterogeneity in the exposure to pre-colonial political centralisation as a proxy for the ability of Indigenous populations in mobilising to resist national integration. We find that the expansion of transport infrastructure was lower in municipalities with a stronger efficacy of Indigenous mobilisation. We demonstrate that this underprovision of public goods can be partly explained by Indigenous identity preservation and high abilities for collective actions.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103652"},"PeriodicalIF":4.6,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-30DOI: 10.1016/j.jdeveco.2025.103645
Anik Ashraf , Elizabeth Lyons
This paper investigates the complementarity between business training and timely access to financial capital for small and medium enterprises (SMEs) in Kenya. All participants in the business support program we study are offered training. One-third of participants are offered loans immediately after training (Concurrent Loan group), one-third are offered loans six weeks after training (Delayed Loan group), and the remaining third are offered loans after another four weeks (Control group). While a long time lag may reduce knowledge retention and application among SMEs, concurrent access to loans and associated business spending may divert the entrepreneurs’ attention away from improving business practices. We find evidence for the latter in both intention-to-treat and treatment-on-the-treated estimates. While SMEs in both Control and Delayed Loan groups improve their business practices, SMEs in the Concurrent Loan group who take loans do not improve their practices at all. Moreover, entrepreneurs who take loans spend less time on their businesses and experience declines in their business revenue.
{"title":"Complementing business training with access to finance: Evidence from SMEs in Kenya","authors":"Anik Ashraf , Elizabeth Lyons","doi":"10.1016/j.jdeveco.2025.103645","DOIUrl":"10.1016/j.jdeveco.2025.103645","url":null,"abstract":"<div><div>This paper investigates the complementarity between business training and timely access to financial capital for small and medium enterprises (SMEs) in Kenya. All participants in the business support program we study are offered training. One-third of participants are offered loans immediately after training (<em>Concurrent Loan</em> group), one-third are offered loans six weeks after training (<em>Delayed Loan</em> group), and the remaining third are offered loans after another four weeks (<em>Control</em> group). While a long time lag may reduce knowledge retention and application among SMEs, concurrent access to loans and associated business spending may divert the entrepreneurs’ attention away from improving business practices. We find evidence for the latter in both intention-to-treat and treatment-on-the-treated estimates. While SMEs in both Control and Delayed Loan groups improve their business practices, SMEs in the Concurrent Loan group who take loans do not improve their practices at all. Moreover, entrepreneurs who take loans spend less time on their businesses and experience declines in their business revenue.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103645"},"PeriodicalIF":4.6,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-30DOI: 10.1016/j.jdeveco.2025.103653
Shouhan Dai, Binlei Gong, Peinan Hu, Xiaoyun Wei
This study examines how pension schemes influence land reallocation and agricultural productivity. While previous research typically groups households based on the presence of elderly members, we distinguish between households where the elderly are operators and those where they are not. Our findings show that land is reallocated from elderly-operated to younger-operated households, leading to a 9.8 % increase in agricultural productivity. The rural pension scheme in China drives migration and land leasing out in elderly-operated households, while facilitating rent-in and scale expansion in younger households. These findings offer new insights into how pension schemes can enhance agricultural factor reallocation and productivity.
{"title":"Rural pension, factor reallocation and agricultural productivity: Evidence from China","authors":"Shouhan Dai, Binlei Gong, Peinan Hu, Xiaoyun Wei","doi":"10.1016/j.jdeveco.2025.103653","DOIUrl":"10.1016/j.jdeveco.2025.103653","url":null,"abstract":"<div><div>This study examines how pension schemes influence land reallocation and agricultural productivity. While previous research typically groups households based on the presence of elderly members, we distinguish between households where the elderly are operators and those where they are not. Our findings show that land is reallocated from elderly-operated to younger-operated households, leading to a 9.8 % increase in agricultural productivity. The rural pension scheme in China drives migration and land leasing out in elderly-operated households, while facilitating rent-in and scale expansion in younger households. These findings offer new insights into how pension schemes can enhance agricultural factor reallocation and productivity.</div></div>","PeriodicalId":48418,"journal":{"name":"Journal of Development Economics","volume":"179 ","pages":"Article 103653"},"PeriodicalIF":4.6,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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