Cusp Catastrophe Regression and Its Application in Public Health and Behavioral Research

The cusp catastrophe model is an innovative approach for investigating a phenomenon that consists of both continuous and discrete changes in one modeling framework. However, its application to empirical health and behavior data has been hindered by the complexity in data-model fit. In this study, we reported our work in the development of a new modeling method—cusp catastrophe regression (RegCusp in short) by casting the cusp catastrophe into a statistical regression. With the RegCusp approach, unbiased model parameters can be estimated with the maximum likelihood estimation method. To validate the RegCusp method, a series of simulations were conducted to demonstrate the unbiasedness of parameter estimation. Since the estimated residual variance with the Fisher information matrix method was over-dispersed, a bootstrap re-sampling procedure was developed and used as a remedy. We also demonstrate the practical applicability of the RegCusp with empirical data from an NIH-funded project to evaluate an HIV prevention intervention program to educate adolescents in the Bahamas for condom use. Study findings indicated that the model parameters estimated with RegCusp were practically more meaningful than those estimated with comparable methods, especially the estimated cusp point

The iterative properties of solutions for a singular k-Hessian system

In this paper, we focus on the uniqueness and iterative properties of solutions for a singular k-Hessian system involving coupled nonlinear terms with different properties. Unlike the existing work, instead of directly dealing with the system, we use a coupled technique to transfer the Hessian system to an integral equation, and then by introducing an iterative technique, the iterative properties of solution are derived including the uniqueness of solution, iterative sequence, the error estimation and the convergence rate as well as entire asymptotic behaviour

Core human values and their interactions with pro-Tobacco factors on cigarette smoking: The role of factors not explicitly related to a risk behavior

More effective tobacco control requires new data on factors that are not explicitly related to smoking but are influential, such as “Terminal Values” regarding desirable end-states of existence and “Instrumental Values” regarding desirable modes of conduct. Association analysis was conducted among 36 Core Values (18 Terminal and 18 Instrumental) derived from Rokeach’s Value Survey, three risk factors (protobacco media, smoking peers and sensation-seeking), and cigarette smoking using data collected from a sample of 334 medical students in China. The participants were 18 to 24 years old (47% female) and 18.4% of them smoked in the past 30 days. Multivariate analysis indicated that cigarette smoking was negatively associated with nine Terminal Values (e.g., a Sense of Accomplishment and Self-Respect) and ten Instrumental Values (e.g., Clean and Self-Controlled). As expected, when the endorsed number of values/total value scores increased from low to high, the 30-day smoking rate declined from 32.6% - 75.0% to 13.5% - 15.9% (p < .01). The odds ratios (OR) for the endorsed Terminal Values and the total value scores were 0.50 (p < .01) and 0.64 (p < .01) respectively, and the ORs for the endorsed Instrumental Values and the total value scores were 0.42 (p < .01) and 0.44 (

Differences in perception of dysentery and enteric fever and willingness to receive vaccines among rural residents in China.

BACKGROUND: Enteric diseases including dysentery and enteric fever remain significant public health problems in China. While vaccines offer great potential in controlling these diseases, greater understanding of factors influencing acceptance of vaccines is needed to create effective enteric disease control programs in rural China. DESIGN: Cross-sectional quantitative study with randomly sampled households from two sites in China, one experiencing high rates of shigellosis (Zengding) and the other of typhoid/paratyphoid (Lingchuan). METHODS: Sociobehavioral survey data were collected through face-to-face interviews from 501 respondents (56% female) in Zhengding regarding dysentery and 624 in Lingchuan (51% female) regarding enteric fever. Vaccine acceptability was measured by expressed need for vaccination and willingness to pay. Comparative and associative analyses were conducted to assess disease perception, vaccination service satisfaction, likelihood of improvements in water and sanitation, and vaccine acceptability. RESULTS: Nearly all respondents in Lingchuan considered enteric fever to be prevalent in the community, while only one half of the respondents in Zhengding considered dysentery to be problematic (p < 0.01). Nevertheless, more respondents in Zhengding were fearful that a household member would acquire dysentery than were Lingchuan respondents worried that a household member would acquire enteric fever (p < 0.01). Perceived vulnerability of specific subgroups (odds ratios ranging from 1.6 to 8.1), knowing someone who died of the disease (odds ratio reached infinity) and satisfaction with past vaccination services (odds ratios reached infinity) were consistently associated with perceived need for vaccines of target populations of all age groups while the association between perception of sanitary improvement and vaccine need was limited. Perceived need for a vaccine was associated with willingness to pay for the vaccine. CONCLUSIONS: Perceptions of enhanced vulnerability of specific subgroups to a disease and satisfactory experiences with vaccination services may increase the perceived need for a vaccine, leading to increased willingness to pay for vaccine. Vaccines are not perceived as important for the elderly

Associations between Leisure Activities and HIV Risk Behaviors among Rural Migrants in Urban China

Although much has been documented on factors affecting HIV risk behavior among rural-to-urban migrants in China, data are lacking on the impact of leisure activities. In this study, we examined the association between leisure activities and HIV risk behavior among a sample of rural-to-urban migrants from two large cities (Beijing and Nanjing) in China. Cross-sectional data were analyzed for a sample of 4,085 participants aged 18 to 30 years (40.5% females). Findings from the analysis indicated that although the migrants worked long hours, they engaged in a number of activities when they did not work, including watching television (60.2%), reading (59.1%), sleeping (55.6%), and chatting with friends and co-workers (45.0%). Multiple regression analysis indicated that reading, doing chores (females only), listening to radio programs/audio CDs (male only) were associated with reduced likelihood of HIV risk behavior while playing cards in groups, visiting entertaining installments, watching videos (including Xrated, males only), and wondering around (females only) were associated with increased likelihood of HIV risk behavior. Findings of this study suggest that constructive and individualized activities (e.g., reading, listening to radios, and doing chores) may prevent migrants from engage in HIV risk behaviors while group and entertaining activities related to drugs and sex may increase the odds for migrants to engage in HIV risk behaviors. Prevention research should consider leisure activities as both an influential factor (including time trends and gender differences) for program development and an important venue for program delivery

Disclosure appraisal mediating the association between perceived stigma and HIV disclosure to casual sex partners among HIV+ MSM: a path model analysis

HIV stigma is widely believed to be related to HIV disclosure. However, there is a dearth of studies examining the mechanisms that link stigma to disclosure. This is a specific study to assess the relationship between perceived stigma and HIV disclosure to casual sex partners based on a social cognitive theory. HIV+ men who have sex with men (MSM) from two U. S. cities (N = 297) completed questionnaires administered using audio computer-assisted self-interviewing. Path modeling analysis was used to assess the theory-based structural relationships. Perceived stigma was negatively associated with attitudes, intention and behavior of HIV disclosure to casual sex partners. The association was fully mediated by disclosure appraisal, including disclosure outcome expectations, costs and self-efficacy. Findings of this study add new knowledge regarding HIV stigma and disclosure, and provide timely data supporting more effective behavioral interventions to encourage HIV disclosure among MSM

Old-Age Support System and Policy Reform in China

With the on-going economic transition from the central planned system to a marketoriented system, the population aging process in China is also accelerating, and the support system for the elderly becomes an important issue demanding attention. With data from Chinese national statistics and a regional probability sampling survey in Wuhan Area, two supporting systems for the aged in China are examined in this paper. After a briefing of the population aging process in China, a detailed discussion of the two supporting systems, i.e. the formal and the informal support systems for the aged, including arrangement, operation and funding mechanisms of the systems, is made in terms of policy reform. Then follows an international comparison to highlight features and problems of the Chinese systems. Finally, solutions are proposed for the restructuring of China's pension systems

On the energy transfer from nanocrystalline ZnS to Tb 3+ ions confined in reverse micelles

Abstract ZnS nanoparticles with different sizes are synthesized using a reverse micelles method in the presence of Tb 3+ ions. The photoluminescence, excitation and absorption spectra of ZnS/Tb 3+ NPs are studied to elucidate remarkable energy transfer from both ZnS host and the surfactant, i.e., AOT, to Tb 3+ ions. When Tb 3+ ions are introduced merely on the outside of ZnS nanoparticles in reverse micelles, obvious energy transfer from ZnS to the Tb 3+ ions is also observed, indicating the important role of spatial confinement on the performance of energy transfer between host and luminescent centers which are even not doped into the host lattices

Effects of multi-organ crosstalk on the physiology and pathology of adipose tissue

In previous studies, adipocytes were found to play an important role in regulating whole-body nutrition and energy balance, and are also important in energy metabolism, hormone secretion, and immune regulation. Different adipocytes have different contributions to the body, with white adipocytes primarily storing energy and brown adipocytes producing heat. Recently discovered beige adipocytes, which have characteristics in between white and brown adipocytes, also have the potential to produce heat. Adipocytes interact with other cells in the microenvironment to promote blood vessel growth and immune and neural network interactions. Adipose tissue plays an important role in obesity, metabolic syndrome, and type 2 diabetes. Dysfunction in adipose tissue endocrine and immune regulation can cause and promote the occurrence and development of related diseases. Adipose tissue can also secrete multiple cytokines, which can interact with organs; however, previous studies have not comprehensively summarized the interaction between adipose tissue and other organs. This article reviews the effect of multi-organ crosstalk on the physiology and pathology of adipose tissue, including interactions between the central nervous system, heart, liver, skeletal muscle, and intestines, as well as the mechanisms of adipose tissue in the development of various diseases and its role in disease treatment. It emphasizes the importance of a deeper understanding of these mechanisms for the prevention and treatment of related diseases. Determining these mechanisms has enormous potential for identifying new targets for treating diabetes, metabolic disorders, and cardiovascular diseases

Diagnostic and prognostic role of circRNAs in pancreatic cancer: a meta-analysis

BackgroundCircular RNAs (circRNAs) are types of endogenous noncoding RNAs produced by selective splicing that are expressed highly specifically in various organisms and tissues and have numerous clinical implications in the regulation of cancer development and progression. Since circRNA is resistant to digestion by ribonucleases and has a long half-life, there is increasing evidence that circRNA can be used as an ideal candidate biomarker for the early diagnosis and prognosis of tumors. In this study, we aimed to reveal the diagnostic and prognostic value of circRNA in human pancreatic cancer (PC).MethodsA systematic search for publications from inception to 22 July 2022 was conducted on Embase, PubMed, Web of Science (WOS), and the Cochrane Library databases. Available studies that correlated circRNA expression in tissue or serum with the clinicopathological, diagnostic, and prognostic values of PC patients were enrolled. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were used to evaluate clinical pathological characteristics. Area under the curve (AUC), sensitivity, and specificity were adopted to assess diagnostic value. Hazard ratios (HRs) were utilized to assess disease-free survival (DFS) and overall survival (OS).ResultsThis meta-analysis enrolled 32 eligible studies, including six on diagnosis and 21 on prognosis, which accounted for 2,396 cases from 245 references. For clinical parameters, high expression of carcinogenic circRNA was significantly associated with degree of differentiation (OR = 1.85, 95% CI = 1.47–2.34), TNM stage (OR = 0.46, 95% CI = 0.35–0.62), lymph node metastasis (OR = 0.39, 95% CI = 0.32–0.48), and distant metastasis (OR = 0.26, 95% CI = 0.13–0.51). As for clinical diagnostic utility, circRNA could discriminate patients with pancreatic cancer from controls, with an AUC of 0.86 (95% CI: 0.82–0.88), a relatively high sensitivity of 84%, and a specificity of 80% in tissue. In terms of prognostic significance, carcinogenic circRNA was correlated with poor OS (HR = 2.00, 95% CI: 1.76–2.26) and DFS (HR = 1.96, 95% CI: 1.47–2.62).ConclusionIn summary, this study demonstrated that circRNA may act as a significant diagnostic and prognostic biomarker for pancreatic cancer