ALBERT

Description: In recent years, thermosensitive poly(N-isopropylacrylamide) (PNIPAM) microspheres have received extensive attention due to their many advantages, and their size and swelling ratio are two crucial factors. In this paper, homogeneous and hollow thermosensitive microspheres were prepared by free radical polymerization in an aqueous solution. The effects of the process parameters on the size of the microspheres were studied. The results indicated that the change in size during reaction at different temperatures was not obvious. The size of the microspheres ranged from 802 ± 35.4 nm to 423 ± 33.7 nm with the changes in the dosage of the initiator. Meanwhile, it was observed that the size of microspheres was slightly reduced due to the increase of reaction time. When the dosage of methyl methacrylate (MAA) is increased, the size of the hollow microspheres increased by more than 110%. The average size of the microspheres was smaller when the content of sodium dodecyl sulfate (SDS) was 3 wt%. The microspheres with varying reaction parameters showed a continuous decreasing swelling ratio when the temperatures were changed from 28 °C to 35 °C. In comparison with homogeneous microspheres, the average swelling ratio of hollow microspheres was larger.

Description: The objective of this study is to follow the composite theory approach to analyze the effect of social capital on self-rated mental health in rural and urban China. Our nationally representative sample includes 10,968 respondents from 130 county-level communities. Two-level random-coefficient linear regressions, which model individual and community variations in subjective mental health, were estimated by taking the hierarchical structure of the dataset into account. We found that a significant proportion of the total variations in self-rated mental health were explained at the community level. We also found an association between low contextual civic trust and poor self-rated mental health after adjusting for individual social capital and individual socioeconomic-demographic variables. The study also revealed that: (1) in rural areas a positive relationship between civic and political trust and mental health existed both at the individual and the community level, respectively; and (2) in urban areas, only political trust at the individual level contributed to better mental health. In addition, the individual and community level political participation exhibited a positive impact on mental health measures in both rural and urban China. The individual level civic participation was positively associated to the outcome variable. However, the community-level civic participation seemed to negatively impact mental health in urban area. Our findings emphasize the importance of both individual and community-level healthcare interventions in China. Finally, this study also found that human capital covariates remained important predictors of self-rated mental health status even after controlling social capital both at individual and community levels. This study suggested that the composite thesis could provide a more convincing narrative than other theories in explaining the effects of both human and social capital on health.