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521.
A novel method was used to incorporate in vivo host–pathogen dynamics into a new robust outbreak model for legionellosis. Dose‐response and time‐dose‐response (TDR) models were generated for Legionella longbeachae exposure to mice via the intratracheal route using a maximum likelihood estimation approach. The best‐fit TDR model was then incorporated into two L. pneumophila outbreak models: an outbreak that occurred at a spa in Japan, and one that occurred in a Melbourne aquarium. The best‐fit TDR from the murine dosing study was the beta‐Poisson with exponential‐reciprocal dependency model, which had a minimized deviance of 32.9. This model was tested against other incubation distributions in the Japan outbreak, and performed consistently well, with reported deviances ranging from 32 to 35. In the case of the Melbourne outbreak, the exponential model with exponential dependency was tested against non‐time‐dependent distributions to explore the performance of the time‐dependent model with the lowest number of parameters. This model reported low minimized deviances around 8 for the Weibull, gamma, and lognormal exposure distribution cases. This work shows that the incorporation of a time factor into outbreak distributions provides models with acceptable fits that can provide insight into the in vivo dynamics of the host‐pathogen system. 相似文献
522.
《统计学通讯:模拟与计算》2012,41(6):688-709
We begin by definition of semi-Markov flow and discussion of its properties. Asymptotic behavior of multi-server and single-server queueing systems is studied under assumption of time-compression or service time growth. The results obtained are used for calculation of large systems reliability. Statistical estimates of parameters involved are also provided. 相似文献
523.
Fengyan Tang 《China Journal of Social Work》2017,10(1):39-51
As a critical community resource, the senior centre has provided older Americans with a wide array of recreational, nutritional, health, and social service programmes. Funding resources include the Older Americans Act allocations, local organisations and governments, national charities, voluntary associations, and religious associations. The types of programmes offered at a senior centre reflect two models: social agency model or voluntary organisation model. The five most popular programmes are nutrition, health and fitness, recreation, volunteering, and social services. Participation in senior centre activities has positive impacts on the overall well-being of older adult participants. With the rapid growth in the ageing population and improved life expectancy in China, senior centres may serve as a focal point for Chinese older adults by providing a broad spectrum of social services to enhance the well-being of community-dwelling older adults, to support their independence and dignity, and to facilitate ageing in place in later life. 相似文献
524.
关于我国的城市规划管理权限一直存在"集中"与"放权"的讨论,并且城市规划管理体制也存在差异。通过对全国部分城市的规划管理体制进行梳理,从市、区(县、市)两级分权视角总结出我国城市规划管理体制中的"垂直型"、"半垂直型"和"非垂直型"三种典型模式,分别以南京、北京和上海为案例分析三种规划管理体制典型模式的主要特点和事权划分,并对其各自的优缺点进行比较,最后提出我国城市规划管理体制改革的若干建议,包括将规划决策权"上收"与实施管理重心"下移"、建立"市—区—镇(街)"三级规划管理机构体系、整合市区两级规划部门内部机构设置形成"大处室"和"大科室"以及完善城市规划委员会制度等。 相似文献
525.
Unemployment among persons with disabilities is high. The situation is worse for women with disabilities as they experience multiple disadvantages on account of gender and disability. The condition for women with disabilities in Ghana could be more complicated, given the intersection of disability, gender, poverty, cultural beliefs and practices. As employment provides not only income for women with disabilities but opportunities for social participation and increases psychological well-being as well as self-esteem, it is imperative to remove barriers that hinder their employment. The current study examines issues associted with the unemployment of women with physical disabilities in Tamale, Ghana, and makes recommendations to policy-makers and practitioners in order to improve the condition of persons with disabilities in general, and particularly women with disabilities. 相似文献
526.
《Journal of Statistical Computation and Simulation》2012,82(11):1727-1744
Interval-valued variables have become very common in data analysis. Up until now, symbolic regression mostly approaches this type of data from an optimization point of view, considering neither the probabilistic aspects of the models nor the nonlinear relationships between the interval response and the interval predictors. In this article, we formulate interval-valued variables as bivariate random vectors and introduce the bivariate symbolic regression model based on the generalized linear models theory which provides much-needed exibility in practice. Important inferential aspects are investigated. Applications to synthetic and real data illustrate the usefulness of the proposed approach. 相似文献
527.
Measuring Children's Experience of Their Right to Participate in School and Community: A Rights‐Based Approach
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This paper discusses the development of a children's rights‐based measure of participation and the findings from its use in a survey of 10‐ to 11‐year‐old children (n = 3773). The measure, which was developed in collaboration with a group of children, had a high reliability (Cronbach's alpha = 0.89). Findings suggest that children's positive experience of their participation rights is higher in school than in community, and higher for girls compared to boys. It is argued that involving children in the ‘measurement’ of their own lives has the potential to generate more authentic data on children's lived experiences. 相似文献
528.
529.
Recently Beh and Farver investigated and evaluated three non‐iterative procedures for estimating the linear‐by‐linear parameter of an ordinal log‐linear model. The study demonstrated that these non‐iterative techniques provide estimates that are, for most types of contingency tables, statistically indistinguishable from estimates from Newton's unidimensional algorithm. Here we show how two of these techniques are related using the Box–Cox transformation. We also show that by using this transformation, accurate non‐iterative estimates are achievable even when a contingency table contains sampling zeros. 相似文献
530.
Child‐caregiver Attachment Representations in a Non‐Western Context: The Feasibility and Cultural Equivalence of Story Stems in Urban Ghana
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![点击此处可从《Social Development》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Story stem measures are an increasingly popular method for assessing the attachment representations of young children, but little is known of their cross‐cultural applicability. This study aimed to characterise the attachment representations in 73 five‐ to eight‐year‐old children in urban Ghana, West Africa, using the Manchester Child Attachment Story Task (MCAST) to test its feasibility, psychometric characteristics and concurrent associations with caregiver‐ and teacher‐rated child behaviour, and to conduct a qualitative thematic analysis of methodological observations. Among the classifiable cases (92 percent), all attachment classifications were observed, yielding a higher rate of secure attachment than in European samples. Inter‐rater reliability, internal consistency, and internal structure were reasonable and largely similar to European studies, although one structural difference was the separation of ‘child assuagement of distress’ from other secure‐related items. MCAST narratives were associated with teacher‐ and caregiver‐rated hyperactivity, but internal consistency was low in most Strengths and Difficulties Questionnaire scales. Possible culturally‐sensitive explanations for our psychometric and qualitative findings are discussed. Overall, story stems are a promising tool for accessing attachment representations in non‐Western samples, although modifications are likely to improve cross‐cultural equivalence when applied to non‐Western cultures. Further investigation is needed to link MCAST outcomes to parenting and socio‐emotional development. 相似文献