BackgroundThis study describes the patterns and socioeconomic influences of tobacco use among adults in tobacco-cultivating regions of rural southwest China.MethodsA cross-sectional survey was conducted in 8681 adults aged ≥18 years in rural areas of Yunnan Province, China from 2010 to 2011. A standardized questionnaire was administered to obtain data about participants’ demographic characteristics, individual socioeconomic status, ethnicity, self-reported smoking habits, and exposure to secondhand smoke (SHS). The socioeconomic predictors of current smoking, nicotine addiction, and SHS exposure were analyzed using multivariate logistic regression.ResultsThe prevalence rates of tobacco use were much higher in men compared with women (current smoking 68.5% vs. 1.3%; and nicotine dependence 85.2% vs. 72.7%). However, the rate of SHS exposure was higher in women compared with men (76.6% vs. 70.5%). Tobacco farmers had higher prevalence rates of current smoking, nicotine dependence, and SHS exposure compared with participants not engaged in tobacco farming (P<0.01). Most tobacco users (84.5%) reported initiating smoking during adolescence. A total of 81.1% of smokers smoked in public places, and 77.6% smoked in workplaces. Individuals belonging to an ethnic minority had a lower probability of SHS exposure and nicotine dependence. Individual educational level was found to be inversely associated with the prevalence of current smoking, exposure to SHS, and nicotine dependence. Higher annual household income was associated with a greater risk of nicotine dependence.ConclusionsThis study suggests that tobacco control efforts in rural southwest China must be tailored to address tobacco-cultivating status and socioeconomic factors.

A number of studies have evaluated two functional polymorphisms on p53 Arg72Pro and GSTP1 Ile105Val, in relation to esophageal cancer susceptibility. However, the results remain conflicting rather than conclusive. This meta-analysis on 2919 cases and 4074 controls for p53 Arg72Pro and 1885 cases and 2194 controls for GSTP1 Ile105Val from 13 published case-control studies showed that no significant general main effects for GSTP1 Ile105Val on esophageal cancer risk. However, we found that the p53 Arg72Pro was associated with an increased risk of esophageal cancer ((Pro/Arg +Pro/Pro) versus Arg/Arg: OR=1.20, 95%CI=1.06-1.36) without any between-study heterogeneity.In the stratified analysis by ethnicity, we found that the increased esophageal cancer risk associated with p53 Arg72Pro polymorphism was more evident in Asian group ((Pro/Arg +Pro/Pro) versus Arg/Arg: OR=1.35, 95%CI=1.14-1.60, P=0.09 for heterogeneity test), although we still failed to find any significant association between GSTP1 Ile105Val polymorphism and esophageal cancer risk in different ethnicity. These results suggest that p53 Arg72Pro polymorphism, but not GSTP1 Ile105Val, may contribute to esophageal cancer development, especially in Asian. Additional well-designed large studies were required for the validation of this association.

Adolescents are disproportionately represented in nations vulnerable to humanitarian crises. The mental health effects of exposure to trauma are significant, but evidence concerning the experience of disaster-affected adolescents in Asia is limited. The current study aimed to investigate expressions of psychological distress and behavioral effects of exposure to natural disasters among adolescents in China and Nepal. Key informant interviews and focus group discussions were conducted with adolescents, caregivers, teachers and experts in disaster-affected districts of Yunnan Province, China (n = 79), and Kathmandu Valley, Nepal (n = 62). Open coding and thematic content analysis were employed to examine themes within the data. Indicators of distress were categorized in four domains that reflected expressions of anxiety and stress, mood difficulties, somatic complaints, and behavioral changes for adolescent disaster survivors. Differential reports of psychological concerns by gender were evident in Nepal but not China. Post-traumatic growth and strengthened connections between adolescents and their families were described in both settings. The findings complement similar reports from disaster-affected populations globally that have highlighted cross-cultural elements manifest in adolescents’ descriptions of distress. Sustainable mental health services that are sensitive to adolescents’ experiences of trauma and their unique capabilities will be a necessary component of long-term rehabilitation following disasters.

ObjectivesTo examine contextual and individual demographical predictors of smoking and exposure to second-hand smoke (SHS) in a tobacco-cultivating rural area of southwest China.MethodsA cross-sectional survey of 4070 consenting individuals aged 18 years or more was conducted in 2010. Information on demographical characteristics, tobacco smoking status and SHS exposure were obtained by a standard questionnaire. Multilevel logistic regression was used to model the variation in prevalence of smoking and SHS exposure.ResultsIn the study population, the prevalence rates of smoking and exposure to SHS were 63.5% and 74.7% for men, and 0.6% and 71.2% for women, respectively. Men were more likely to use tobacco than women: OR 8.27, 95% CI (4.83 to 10.97). Age was inversely associated with the probability of tobacco use (OR 0.98, 95% CI 0.97 to 0.99), and exposure to SHS (OR 0.97, 95% CI 0.96 to 0.99). Individual educational level was inversely associated with smoking, but showed no association with exposure to SHS. Adults who did not grow tobacco were less likely to consume tobacco (OR 0.75, 95% CI 0.57 to 0.99) and to be exposed to SHS (OR 0.76, 95% CI 0.58 to 0.99). Living in a high-income community was associated with a low rate of current smoking (OR 0.66, 95% CI 0.57 to 0.77) and SHS exposure (OR 0.58, 95% CI 0.52 to 0.65).ConclusionsFuture interventions to reduce smoking and exposure to SHS in China should focus more on tobacco farmers, less-educated individuals and on poor rural communities.

Using a contingent claims model, we examine the impacts of both operating leverage and financial leverage on a firm's investment decisions in the context of capacity expansion. Our model shows that quasi-fixed operating costs could significantly mitigate the underinvestment problem for debt-financed firms. The existing debt induces equity holders to delay equity-financed expansion because the expanded earnings base will also benefit the debt holders by lowering the bankruptcy risk. The operating costs decrease this type of wealth transfer from equity holders to debt holders by magnifying the bankruptcy risk of the existing debt upon investment. By applying the Cox proportional hazard model on a large sample of publicly traded U.S. firms over 1966-2016, we offer empirical support for the theoretical predictions. The results are robust to various measures of operating leverage.