Can market-oriented and government-led spatial agglomeration of factories reduce carbon emission intensity? Evidence from China.

Both market-oriented and government-led spatial agglomeration of factories profoundly affect China's carbon emission intensity. However, few studies have comprehensively examined the effect of spatial agglomeration of factories driven by different motivations on carbon emission intensity, and often ignore the moderating effect of local government attention to the environment. This study attempts to incorporate market-oriented and government-led spatial agglomeration of factories into the same analytical framework and examine their interaction effects on carbon emission intensity. We first calculate an Agglomeration Index based on the geographic coordinates of micro-factories to measure market-oriented agglomeration of factories, and take development zone policies as a proxy for government-led agglomeration of factories. Based on city-level data from 1998 to 2013, we empirically analyze their impacts on carbon emission intensity and further explore regional heterogeneity and mechanisms. The results show that both the market-oriented and government-led spatial agglomeration of factories can significantly reduce carbon emission intensity through scale effect, innovation effect and structure effect. However, the agglomeration of factories caused by government forces has weakened the original effect of market-oriented agglomeration of factories in reducing carbon emission intensity. Heterogeneity analysis indicates that government-led agglomeration of factories is more effective in reducing carbon emission intensity in less-developed regions. Furthermore, the improvement of the governments' attention to the environment can further exert the positive effect of spatial agglomeration of factories on carbon emission intensity. Our study deepens the understanding of the effects of spatial agglomeration of factories caused by different motivations, and provides a reference for China and other developing countries to formulate relevant policies for reducing carbon emission intensity.

The causal effect and autonomous buffering mechanisms of large-scale internal migration on carbon emissions: evidence from China.

Large-scale internal migration and unprecedented urbanization have dramatically promoted economic growth in China, resulting in a rapid surge in carbon emissions in urban areas. However, few studies have investigated the causal effect of mass internal migration on carbon emissions or examined the effects of autonomous mitigation mechanisms, such as population agglomeration and technological innovation. This study identifies the causal effect of internal migration on prefectural-level cities' carbon emissions in China by employing an instrumental variable and further investigates the buffering effect of population agglomeration and technological innovation using mediating effect models. The results show that mass internal migration has a substantial impact on increasing carbon emissions in prefectural-level cities. If the proportion of inflowed migrants rises by 1% point, prefectural-level cities' carbon emissions per capita will increase by 1.9%. A series of robustness tests confirms the result. Population migration also promotes population agglomeration and technological innovation in urban areas. Two autonomous mechanisms buffer 11.9% and 5.4% of prefectural-level cities' incremental carbon emissions per capita caused by population migration, respectively. This study highlights the crucial role of population agglomeration and technological innovation in mitigating carbon emissions in cities experiencing significant migrant inflows and provides several implications for formulating relevant policies.

Which factors affect the performance of technology business incubators in China? An entrepreneurial ecosystem perspective.

To examine which factors affect the performance of technology business incubators in China, the present study proposes an entrepreneurial ecosystem framework with four key areas, i.e., people, technology, capital, and infrastructure. We then assess this framework using a three-year panel data set of 857 national-level technology business incubators in 33 major cities from 28 provinces in China, from 2015 to 2017. We utilize factor analysis to downsize dozens of characteristics of these technology business incubators into seven factors related to the four proposed areas. Panel regression model results show that four of the seven factors related to three areas of the entrepreneurial ecosystem, namely people, technology, and capital areas, have statistically significant associations with an incubator's performance when applied to the overall national data set. Further, seven factors related to all four areas have various statistically significant associations with an incubator's performance in five major regional data set. In particular, a technology related factor has a consistently statistically significant association with the performance of the incubator in both national model and the five regional models, as we expected.

The Impact of Natural Disasters on Dietary Intake.

Objectives: In this study, we explored the potential impact of disasters on individuals' fruit and vegetable consumption. Methods: Individual-level data (N = 351,229) from the Behavioral Risk Factor Surveillance System (BRFSS) 2011 survey were merged with county-level disaster declaration data from the Federal Emergency Management Agency (FEMA) based on disaster duration, interview month and residential county. Multilevel mixed-effects generalized linear models were conducted to examine the impact of different types of disasters on self-reported daily fruit, 100% pure fruit juice, beans, green vegetables, orange vegetables, other vegetables and overall vegetables consumption frequencies, adjusting for individual covariates. Results: No associations between disasters and daily fruit and overall vegetable consumption frequency were identified at either national or state levels. Only floods were consistently associated with reduced consumption of orange vegetables. Conclusions: This study did not identify an association between natural disasters and daily overall fruit/vegetable consumption frequency at national or state levels, whereas disasters were found to alter the consumption of certain vegetable subgroup (orange vegetables) slightly. Longitudinal studies with validated and detailed measures on diet and disaster are warranted to advance research in this field.

Impact of Hurricane Katrina on Mental Health among US Adults.

Objectives: Hurricane Katrina was an intense tropical cyclone that made landfall in the United States (US) in August 2005, causing catastrophic damage in several states. This study examined the impact of Hurricane Katrina on mental health status among US adults. Methods: Multilevel regressions based on the difference-in-differences study design were performed on individual-level data (N = 70,267) retrieved from the Behavioral Risk Factor Surveillance System 2004-2006 surveys. Results: Hurricane Katrina was found to be associated with an increase of 0.68 poor mental health days among residents of Katrina-affected states. The negative impact of Hurricane Katrina on mental health status tended to be larger among Louisiana residents, women, young and middle-aged adults, lower income respondents, and those with poor/fair self-rated physical health than among Mississippi residents, men, older adults, higher income respondents, and those with good/excellent self-rated physical health. Conclusion: Hurricane Katrina adversely impacted mental health of residents in Katrina-affected states, and the impact differed across population subgroups. Future studies should investigate other potential risk and protective factors for the mental health consequences of disasters. They should examine long-term impacts on mental health following disasters to better inform population-based mental health interventions for disaster survivors.

Trade openness and the obesity epidemic: a cross-national study of 175 countries during 1975-2016.

PURPOSE: This study assessed the longitudinal relationship between trade openness and obesity rate across 175 countries during 1975-2016. METHODS: Two-way (country and year) fixed-effects regressions were performed to examine the openness index (i.e., sum of export and import over gross domestic product) in relation to country obesity rate, using data from World Health Organization and World Bank. RESULTS: The openness index was found to be positively associated with country obesity prevalence-a 10% increase in the openness index was associated with an increase in obesity rate by 0.80% (95% confidence interval, 0.67%-0.94%). Across continents, the positive relationship between the openness index and obesity prevalence was strongest among Asian countries, followed by countries in North America and Africa. Across income levels, the positive relationship between the openness index and obesity prevalence was strongest among lower middle-income countries, followed by upper middle-income countries and low-income countries. In contrast, no relationship between the two was identified among high-income countries. CONCLUSIONS: Trade openness was positively associated with country obesity prevalence, and its influence concentrated among developing nations. Policy makers should closely monitor the evolution in obesity rate during trade liberalization and nutrition transition to minimize its negative impact on weight-related population health.

Impact of State Laws Governing Physical Education on Attendance Among US High School Students, 2003 to 2017.

PURPOSE: This study assessed the influence of state laws governing physical education (PE) on weekly PE class attendance among US high school students. DESIGN: Cross-sectional. SETTING: 2003 to 2017 US national Youth Risk Behavior Survey (YRBS). PARTICIPANTS: A total of 533 468 high school students. MEASURES: Data on state laws governing PE came from National Cancer Institute's Classification of Laws Associated with School Students (CLASS). Eight distinct state PE policies were scored, with higher scores denoting stronger laws. ANALYSIS: Individual-level YRBS data were merged with CLASS data based on students' residential state and survey year. State fixed-effect negative binomial regressions were performed, adjusting for individual-level characteristics and YRBS survey design. RESULTS: A 1-score increase in state laws governing PE class time, staffing for PE, joint use agreement for physical activity, assessment of health-related fitness, and PE curriculum was associated with an increase in weekly PE attendance by 0.30, 0.28, 0.22, 0.20, and 0.13 days (P < .001), respectively. In contrast, a 1-score increase in state laws governing moderate-to-vigorous-intensity physical activity time in PE, PE proficiency, and recess time was associated with a reduction in weekly PE attendance by 0.25, 0.15, and 0.09 days (P < .001), respectively. The effects of most state PE policies on PE class attendance were larger among girls than boys. CONCLUSION: State PE policies differentially impacted US high school students' PE class attendance, with larger effects on female students.

Chronic Noise Exposure and Adiposity: A Systematic Review and Meta-analysis.

CONTEXT: Noise is a key environmental stressor affecting millions of people worldwide on a daily basis. Chronic exposure to noise may elevate the risk of adiposity through sleep deprivation and heightened stress level. EVIDENCE ACQUISITION: A literature search was conducted in the PubMed, Web of Science, and Cochrane Library for articles published until February 20, 2018, that assessed the relationship between noise and adiposity. A standardized data extraction form was used to collect methodologic and outcome variables from each included study. EVIDENCE SYNTHESIS: Eleven studies were identified, among which seven reported a positive association between chronic exposure to noise and adiposity. Compared with their counterparts exposed to a lower noise level, adults chronically exposed to a noise level above 55-60 dBA were associated with a higher waist circumference by 7.5 mm per year (95% CI=3.6, 11.4, I2=0.0%). An increase in chronic exposure to noise by 10 dBA was found to be associated with a higher waist circumference by 7.0 mm per year (95% CI=2.5, 11.6, I2=93.9%) in the random effect model but not the inverse variance heterogeneity model. Chronic noise exposure was not found to be associated with BMI. CONCLUSIONS: Noise tends to be positively associated with waist circumference but not BMI in adults, but current evidence remains limited. Future studies should assess the impact of noise on adiposity in alternative settings and across population subgroups and geographic areas, examine different sources of noise, and elucidate the biomedical and psychosocial pathways linking noise to adiposity.

State Laws Governing Competitive Foods and Beverages Sold in Schools and Childhood Obesity among Children with Special Healthcare Needs, 2007-2016.

Objective In this study, we assessed the impact of state laws governing competitive foods/beverages sold in schools on childhood overweight/obesity among children aged 10-17 years with and without special healthcare needs (SHCN). Methods Individual-level data from 2007-2008, 2011-2012, and 2016 National Survey of Children's Health (N = 108,009) were merged to data on state codified laws regulating competitive foods/beverages sold in schools based on children's residential state and survey year. State random-effect logistic regressions were performed to estimate the odds of childhood overweight/obesity in relation to the presence and strength of competitive food/beverage laws, adjusting for child/family characteristics and state soda sales tax. Results No association between state laws governing competitive foods/beverages sold in schools and childhood overweight/obesity was identified among children with and without SHCN. In addition, no impact of state soda sales tax on childhood overweight/obesity was found among children with SHCN. Conclusions No protective effect of state laws governing competitive foods/beverages sold in schools against obesity risk among children with SHCN was revealed. This study has design and measurement limitations. Future research should replicate findings of this study and assess school district competitive food/beverage policies in relation to adiposity among this highly vulnerable child population.

Impact of ambient air pollution on obesity: a systematic review.

BACKGROUND/OBJECTIVES: Over 80% of the global populations living in urban areas are exposed to air quality levels that exceed the World Health Organization limits. Air pollution may lead to unhealthy body weight through metabolic dysfunction, chronic disease onset, and disruption of regular physical activity. SUBJECTS/METHODS: A literature search was conducted in the PubMed and Web of Science for peer-reviewed articles published until September 2017 that assessed the relationship between air pollution and body weight status. A standardized data extraction form was used to collect methodological and outcome variables from each eligible study. RESULTS: Sixteen studies met the selection criteria and were included in the review. They were conducted in seven countries, including the US (n = 9), China (n = 2), Canada (n = 1), Italy (n = 1), The Netherlands (n = 1), Serbia (n = 1), and South Korea (n = 1). Half of them adopted a longitudinal study design, and the rest adopted a cross-sectional study design. Commonly examined air pollutants included PM, NO2, SO2, O3, and overall air quality index. Among a total of 66 reported associations between air pollution and body weight status, 29 (44%) found air pollution to be positively associated with body weight, 29 (44%) reported a null finding, and the remaining eight (12%) found air pollution to be negatively associated with body weight. The reported associations between air pollution and body weight status varied by sex, age group, and type of air pollutant. Three pathways hypothesized in the selected studies were through increased oxidative stress and adipose tissue inflammation, elevated risk for chronic comorbidities, and insufficient physical activity. CONCLUSIONS: Concurrent evidence regarding the impact of air pollution on body weight status remains mixed. Future studies should assess the impact of severe air pollution on obesity in developing countries, focus on a homogenous population subgroup, and elucidate the biomedical and psychosocial pathways linking air pollution to body weight.

Diet and self-rated health among oldest-old Chinese.

INTRODUCTION: Dietary behavior is a central modifiable risk factor for human health. This study examined the longitudinal relationship between dietary habits and self-rated health among the oldest-old Chinese. METHODS: Participants aged 80 years and above (N = 7273) were first interviewed in 1998 and followed in subsequent waves 2-3 years apart till 2011-2012 in the Chinese Longitudinal Healthy Longevity Survey. Cox proportional hazards regressions were performed to estimate the effects of dietary habits on poor self-rated health, adjusting for various individual characteristics. RESULTS: Compared to those who rarely/never consumed fruit, vegetable, meat, egg, and soybean-derived product, participants consuming such products almost every day were 28%, 20%, 32%, 16%, and 16% less likely to report poor self-rated health during follow-up, respectively. Compared to those who rarely/never consumed fruit, meat, fish, soybean-derived product, and tea, participants consuming such products occasionally were 12%, 24%, 11%, 15%, and 14% less likely to report poor self-rated health during follow-up, respectively. Compared to those who rarely/never consumed sugar, participants consuming sugar almost every day were 14% more likely to report poor self-rated health during follow-up. The effects of dietary habits on self-rated health to some extent differed by sex. CONCLUSIONS: Oldest-old Chinese could gain health benefit from regular consumption of fruit, vegetable, meat, fish, egg, soybean-derived product, and tea; whereas their sugar consumption may need to be reduced. Future research is warranted to establish the recommended daily nutrient allowances for the oldest-old adults and better address the nutritional needs of this vulnerable population.

Impact of ambient air pollution on physical activity among adults: a systematic review and meta-analysis.

AIMS: This study systematically reviewed literature regarding the impact of ambient air pollution on physical activity among children and adults. METHODS: Keyword and reference search was conducted in PubMed and Web of Science to systematically identify articles meeting all of the following criteria - study designs: interventions or experiments, retrospective or prospective cohort studies, cross-sectional studies, and case-control studies; subjects: adults; exposures: specific air pollutants and overall air quality; outcomes: physical activity and sedentary behaviour; article types: peer-reviewed publications; and language: articles written in English. Meta-analysis was performed to estimate the pooled effect size of ambient PM2.5 air pollution on physical inactivity. RESULTS: Seven studies met the inclusion criteria. Among them, six were conducted in the United States, and one was conducted in the United Kingdom. Six adopted a cross-sectional study design, and one used a prospective cohort design. Six had a sample size larger than 10,000. Specific air pollutants assessed included PM2.5, PM10, O3, and NOx, whereas two studies focused on overall air quality. All studies found air pollution level to be negatively associated with physical activity and positively associated with leisure-time physical inactivity. Study participants, and particularly those with respiratory disease, self-reported a reduction in outdoor activities to mitigate the detrimental impact of air pollution. Meta-analysis revealed a one unit (µg/m3) increase in ambient PM2.5 concentration to be associated with an increase in the odds of physical inactivity by 1.1% (odds ratio = 1.011; 95% confidence interval = 1.001, 1.021; p-value < .001) among US adults. CONCLUSIONS: Existing literature in general suggested that air pollution discouraged physical activity. Current literature predominantly adopted a cross-sectional design and focused on the United States. Future studies are warranted to implement a longitudinal study design and evaluate the impact of air pollution on physical activity in heavily polluted developing countries.