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Overproduction of the deleterious reactive oxygen species (ROS) is one of the major causes of mercury, a heavy metal with diverse applications and environmental presence, induced neuronal and gastrointestinal adversities in exposed organism including Drosophila melanogaster. Sestrin, an oxidative stress responsive gene, emerges as a novel player in the management of oxidative stress response. Due to limited information regarding the role of sestrin in mercury-induced gastrointestinal adversities, it was hypothesized that modulation of sestrin may improve the mercury-induced gastrointestinal adversities in Drosophila. Here, we fed Drosophila with 400 μM HgCl2 and found that sestrin transcriptional level was significantly increased in midguts. Sestrin knockdown in HgCl2-exposed midguts decreased survival rates and climbing ability of flies, and inhibited superoxide dismutase and glutathione-S-transferase activities of midgut epithelieum. Meanwhile, sestrin knockdown in midgut aggravated the HgCl2-induced disruption of intestinal organization by worsening ROS production and cell apoptosis. Immunohistochemical staining data revealed that sestrin knockdown inhibited intestinal stem cell division in HgCl2-exposed midguts. Furthermore, JNK signaling was found to mediated sestrin expression in midgut. Taken together, the study demonstrated that sestrin protects Drosophila midgut from HgCl2-induced oxidative damage by inhibiting ROS production and stimulating the tissue regeneration program under regulation of JNK signaling pathway. This work suggests therapeutic implications of sestrin against heavy metal-induced gastrointestinal adversities in mammals.

How much are Chinese people and various citizen groups concerned about the environment relative to other major public problems? What are the key factors and to what extent do these factors shape individual Chinese environmental concern? Based on a micro-macro model and a county fixed model proposed in this study, we employ nationwide representative public opinion survey data and provincial statistics to examine the determinants and variations of public environmental concern in China. The data shows that environmental concern is not among the top-ranked issue concerns in China overall, but in the urban areas and in the east-coastal region environmental protection features as a rather important issue. Our regression analyses further demonstrate that the Chinese environmental concern is significantly affected by both micro-level socio-demographic variables and macro-level regional economic conditions and environmental risks. In the east-coastal region, such individuals as urbanites with high income are most environmentally concerned. There is a lack of concern over environmental issues among the public in the west region, where little association between individual sociodemographics and their environmental concern is detected. In the central-northeast region, education effect is evident in the rural area. Location contextual factors such as economic development and environmental risk account for most of the observed variations in public environment concern.

Though value-at-risk (VaR) has been widely applied by finance industry, a possibility of multiple optimums that is caused by the nonlinearity in modeling can challenge its application. To deal with this technical issue, we propose a linearized VaR model that employs the mixed 0-1 programing in Lin (2009) P4 model. We further advance the previous models with considering various transaction costs and the optimization of short-selling weights. We compare the performance of buy-and-hold (BH) strategy, the mean-variance (MV) model, the original P4 model, and our linearized P4 (LP4) model by rebalancing a wide scale of international and alternative investments during a period between 2001 and 2012. The results of numerical tests show the superior performance of the VaR models to the BH and the MV portfolios. The LP4 model yields the global optimum and outperforms the corresponding P4 model in both return and risk. The stability of portfolio value generated from the LP4 model supports its higher effectiveness in risk management than the P4 model.

Land requisition has been an important way for local Chinese governments to generate revenue and promote urbanization, but little is known how the land-losing farmers cope. This study investigates the impact of land requisition on farmers’ off-farm labor participation. We provide evidence that rural-urban migration is one way that land-losing farmers now adapt to land requisition. Using data from the China Household Finance Survey, we first show that village characteristics, not household characteristics, are the key determining factors for how likely a household is to lose land. With a traditional difference-in-differences (DD) model and a DD model with individual fixed effects, we show that land loss due to government requisition has a significant migration effect in the total sample: it increases individual migration rates by 4.5–6.8 percentage points. Land requisition has no impact on local off-farm engagement. These findings are robust to using different samples, to correction for sample attrition, and to a falsification test. We also find that the migration effect is experienced in particular by younger and older farmers, by women, and by the better educated. From a policy perspective, the labor allocation response to land requisition identified in this paper suggests that providing job training and social protection to land-losing farmers, and facilitating their migration to cities, could help them to cope with the experience of land loss.

Do elected leaders in an authoritarian regime have any real power? Does grassroots democracy in a one-party state entail parochial problems? Making use of primary survey data covering two election cycles in a mountainous area of China, where an administrative village consists of several natural villages (NVs), we find that elected village heads favor their home NVs in resource allocations, especially when these NVs have a large population. In contrast, the home NVs of appointed Communist Party secretaries do not receive disproportionately more resources, on average. This pattern of resource allocation is compatible with the interest of village heads and suggests that as elected leaders, village heads have some true power in resource distribution.

The compressive deformation behaviors of two new 0.26C–1.56Mn–1.72Si(wt%) based and 0.23C–1.50Mn–1.79Al(wt%) based microalloyed high-strength steels were investigated and compared with each other at the temperatures from 900 °C to 1100 °C and strain rates from 0.01 s −1 to 30 s −1 on Gleeble-1500 thermo-simulation machine. It was found that the flow stress of high Al steel is higher than that of high Si steel at the same hot deformation condition due to the higher solute strengthening parameters (SSPs) of Al than that of Si. The flow stress constitutive equations of hot deformation were developed for both steels, and it was found that the activation energy Q about 396 kJ/mol for the high Si steel was higher than that (310 kJ/mol) for the high Al steel. The dynamic recrystallization behavior of both steels was also investigated and found that Al alloying delayed distinctly the onset of dynamic recrystallization, however, the dynamic recrystallization kinetics of high Al steel was faster than that of high Si steel.

The compressive deformation behaviors of a new 0.23C–1.50Mn–1.79Al (wt%) based microalloyed high-strength steel were investigated at the temperatures from 900 °C to 1100 °C and strain rates from 0.01 s −1 to 30 s −1 on a Gleeble-1500 thermo-simulation machine. The flow stress constitutive equation of hot deformation for this steel was developed with the activation energy Q being about 310 kJ/mol. Activation energy analysis showed that high Al addition in this steel seemed not to affect the activation energy much. A regression expression proposed by Medina and Hernandez [24] to predict the Q value of microalloyed steels was found to have a relative error 2.58% for this steel. The dynamic recrystallization (DRX) analysis showed that the DRX behavior of the experimental steel was evidently affected by both the deformation temperature and the strain rate. The dependence of steady-state grain size, the peak strain and the peak stress on Zener–Hollomon parameter of this steel was plotted and found that the values of Zener–Hollomon exponents of this steel was in reasonable agreement with microalloyed steels without high Al addition.

With rapid economic growth and industrial expansion, China consumes more coal than any other nation. Therefore, it is particularly crucial to forecast China's coal production to help managers make strategic decisions concerning China's policies intended to reduce carbon emissions and concerning the country's future needs for domestic and imported coal. Such decisions, which must consider results from forecasts, will have important national and international effects. This article proposes three improved forecasting models based on grey systems theory: the Discrete Grey Model (DGM), the Rolling DGM (RDGM), and the p value RDGM. We use the statistical data of coal production in China from 1949 to 2005 to validate the effectiveness of these improved models to forecast the data from 2006 to 2010. The performance of the models demonstrates that the p value RDGM has the best forecasting behaviour over this historical time period. Furthermore, this paper forecasts coal production from 2011 to 2015 and suggests some policies for reducing carbon and other emissions that accompany the rise in forecasted coal production.

The rapid economic growth in China is accompanied by a large scale rural-to-urban migration, but over time more children are left behind rural areas. This paper studies how the overweight and underweight status of the rural children is associated with the out migration of others in their household. We find that migration is related to different nutritional outcomes for the left-behind children. The older children (aged 7–12) are more likely to be underweight; the younger (aged 2–6) are less likely to be overweight if left behind without the care of a grandparent. We also find evidence that the remaining adult household members spent less time preparing meals, whereas older children take up more household chores.

Evidence shows that exposure to nutritional adversity in early life has larger long-term impacts on women than on men. Consistent with these findings, our paper shows a higher incidence of disability and illiteracy among female survivors of the Great Chinese Famine (1959-1961). Moreover we find that the better health of male survivors most plausibly reflects higher male excess mortality during the famine, whereas the observed gender difference in illiteracy rate is probably better explained by the culture of son preference.

The paper re-visits the site of a large, World Bank-financed, rural development program in China, 10 years after it began and four years after disbursements ended. The program emphasized community participation in multi-sectoral interventions (including farming, animal husbandry, infrastructure and social services). Data were collected on 2000 households in project and non-project areas, spanning 10 years. A double-difference estimator of the program's impact (on top of pre-existing governmental programs) reveals sizeable short-term income gains that were mostly saved. Only small and statistically insignificant gains to mean consumption emerged in the longer-term — though in rough accord with the average gain to permanent income. The use of community-based beneficiary selection greatly reduced the overall impact, given that the educated poor were under-covered. The main results are robust to corrections for various sources of selection bias, including village targeting and interference due to spillover effects generated by the response of local governments to the external aid.

This paper investigates the impact of land tenure insecurity on the migration decisions of China's rural residents. A simple model first frames the relationship among these variables and the probability that a reallocation of land will occur in the following year. After first demonstrating that a village leader's support for administrative land reallocation carries with it the risk of losing a future election, the paper exploits election-timing and village heterogeneity in lineage group composition and demographic change to identify the effect of land security. In response to an expected land reallocation in the following year, the probability that a rural resident migrates out of the county declines by 2.8 percentage points, which accounts for 17.5 percent of the annual share of village residents, aged 16 to 50, who worked as migrants during the period. This finding underscores the potential importance of secure property rights for facilitating labor market integration and the movement of labor out of agriculture.