Geographic distribution of cardiovascular comorbidities in South Africa: a national cross-sectional analysis

Objectives: We sought to estimate the spatial coexistence of hypertension, coronary heart disease (CHD), stroke and hypercholesterolaemia in South Africa. Design: Cross-sectional. Setting: Sub-Saharan Africa and South Africa. Participants: Data were from 13,827 adults (mean±SD age 39±18 years, 58.4% women) interviewed in the 1998 South African Health and Demographic Survey. Interventions: N/A. Primary and secondary outcome measures: We used multivariate spatial disease models to estimate district-level shared and disease-specific spatial risk components, controlling for known individual risk factors. Results: In univariate analysis, observed prevalence of hypertension and CHD is was high in the south-western parts, and low in the north east. Stroke and high blood cholesterol prevalence appeared to be evenly distributed across the country. In multivariate analysis (adjusting for age, gender, ethnicity, education, urban-dwelling, smoking, alcohol consumption and obesity), hypertension and stroke prevalence were highly concentrated in the south-western parts, whilst CHD and hypercholesterolaemia were highly prevalent in central and top north-eastern corridor, respectively. The shared component, which we took to represent nutrition and other lifestyle factors not accounted for in the model, had a larger effect on cardiovascular disease prevalence in the south-western areas of the country. It appeared to have greater effect on hypertension and CHD. Conclusion: This study suggests a clear geographic distribution of cardiovascular disease in South Africa, driven possibly by shared lifestyle behaviours. These findings might be useful for public health resource allocation in low-income settings.     

疾疫的救治、防控与乡村社会的变迁——青海省黄南藏族自治州牧区个案研究

历史上,现今青海省黄南藏族自治州的牧区存在鼠疫、性病、伤寒、天花等疾疫流行的情况,那里的藏族和蒙古族主要依靠社会力量(其中包括民间藏医、寺院以及人们在日常生活方面的行为规范和约束)对疾疫进行救治,国家和地方政府对当地疾疫的防控干预不多。中华人民共和国成立后,当地医疗卫生事业得到很大的发展,疾疫状况有了明显的改善。调查研究表明,近几十年黄南牧区疾疫救治与防控的进步,不仅表现为由民间自发防控向国家政府行为的转化,还表现为由治疗向预防的发展以及疾疫防控的法制化。它在某些方面改变了民众对传统社会组织与宗教的依赖程度,反映出国家力量对边远民族地区基层社会的管理在不断深入和强化。     

Efficient simulation of tail probabilities in a queueing model with heterogeneous servers

This paper considers a multi-server queue with Markov-modulated Poisson input and server-dependent phase-type service times. We develop an efficient rare-event simulation technique to estimate the probability that the number of customers in this system reaches a high value. Relying on explicit bounds on the probability under consideration as well as the associated likelihood ratio, we succeed in proving that the proposed estimator is of bounded relative error. Simulation experiments illustrate the significant speed-up that can be achieved by the proposed algorithm.     

A two-stage unrelated randomized response model for estimating a rare sensitive attribute in probability proportional to size sampling using Poisson distribution

This paper describes the estimating procedures of mean number of entities that possess a rare sensitive attribute using the Mangat (1992) randomized device, when the population consists of some clusters and the population is again stratified with some clusters in each stratum. Unbiased estimation procedures for the mean number of individuals have been discussed and their properties are described when the parameter of a rare unrelated attribute is assumed to be known and unknown. An empirical study is carried out to show the dominance of the proposed estimator over Lee et al. (2013) estimator.     

浅谈遗传病的治疗

概述了目前对遗传病治疗的两种主要途径－环境工程疗法和基因工程疗法的原理及其应用现状。     

稀土Ni-WC喷焊层组织和耐磨性的研究

本文通过在镍基自熔合金粉末中添少量稀土,探稀土对Ｎｉ－ＷＣ喷焊层组织和耐磨性的影响。结果表明,适量地加入稀土坷以改善喷焊层焊态组织,提高焊层硬度和耐磨性,而且,喷焊粉末具有良好的工艺性能。     

高贵山珍稀濒危重点保护植物资源初步研究

高贵山有珍稀濒危重点保护植物共39种(亚种),其中国务院新近公布的Ⅰ级重点保护植物2种,Ⅱ级重点保护植物10种,国家林业局和省级重点保护植物20种,其他珍稀植物7种．高贵山珍稀濒危重点保护植物具有种类丰富、起源古老、成分复杂的区系特点,在湖北省珍稀濒危植物保护中有着重要地位,应加强对高贵山珍稀濒危植物的保护．     

柠檬酸稀土饲料添加剂生产条件研究

对柠檬酸稀土饲料添加剂生产中的酸度、原料比、温度、沉淀条件等进行了研究．经测定,有机稀土饲料添加剂中稀土氧化物的含量为４０．７％（＞３５％）,对动物有害的元素Ｐｂ,Ｈｇ,Ｃｄ,Ａｓ的含量分别小于２０,０．５,１．０,３．５μｇ／ｇ．对动物的急性毒理实验及蓄积性实验证明,该产品无毒、无残留     

A two-stage Land et al.'s randomized response model for estimating a rare sensitive attribute using Poisson distribution

The crux of this paper is to estimate the mean of the number of persons possessing a rare sensitive attribute based on the Mangat (1992 Mangat, N.S. (1992). Two stage reandomized response sampling procedure using unrelated question. J. Ind. Soc. Agric. Stat. 44(1):82–87. [Google Scholar]) randomization device by utilizing the Poisson distribution in survey sampling. It is shown that the proposed model is more efficient than Land et al. (2011 Land, M., Singh, S., Sedory, S.A. (2011). Estimation of a rare attribute using Poisson distribution. Statistics doi:10.1080/02331888.2010.524300[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) when the proportion of persons possessing a rare unrelated attribute is known. Properties of the proposed randomized response model have been studied along with recommendations. We have also extended the proposed model to stratified random sampling on the lines of Lee et al. (2013 Lee, G.S., Uhm, D., Kim, J.M. (2013). Estimation of a rare sensitive attribute in stratified sampling using Poisson distribution. Statistics 47(3):575–589.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). It has been also shown that the proposed estimator is better than Lee et al.'s (2013 Lee, G.S., Uhm, D., Kim, J.M. (2013). Estimation of a rare sensitive attribute in stratified sampling using Poisson distribution. Statistics 47(3):575–589.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) estimator. Numerical illustrations are also given in support of the present study.     

试论防控SARS与我国传染病法律制度的完善

在防控SARS的过程中,传染病法律制度的理解和执行存在一定问题,暴露出现行法律的不完善之处。通过对现有相关法律的全面分析,明确了防控SARS的法律要求;在阐述相关法律新完善的内容的同时,提出了通过此次SARS疫情的流行过程,仍需要完善现行法治的建议。