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121.
政府相关文件的出台为社会工作专业教育发展带来了机遇。随着社会服务需求市场的逐步形成,社会将迫切需要大量合格的社会工作者。专业教育体系要积极回应这一需求,通过明确培养目标和办学特色、加强师资队伍建设、完善课程体系和教材建设、优化教学过程等,促进人才供给与社会需求之间的对接。 相似文献
122.
A Stochastic Model to Assess the Effect of Meat Inspection Practices on the Contamination of the Pig Carcasses 下载免费PDF全文
Eduardo de Freitas Costa Luis Gustavo Corbellini Ana Paula Serafini Poeta da Silva Maarten Nauta 《Risk analysis》2017,37(10):1849-1864
The objective of meat inspection is to promote animal and public health by preventing, detecting, and controlling hazards originating from animals. With the improvements of sanitary level in pig herds, the hazards profile has shifted and the inspection procedures no longer target major foodborne pathogens (i.e., not risk based). Additionally, carcass manipulations performed when searching for macroscopic lesions can lead to cross‐contamination. We therefore developed a stochastic model to quantitatively describe cross‐contamination when consecutive carcasses are submitted to classic inspection procedures. The microbial hazard used to illustrate the model was Salmonella, the data set was obtained from Brazilian slaughterhouses, and some simplifying assumptions were made. The model predicted that due to cross‐contamination during inspection, the prevalence of contaminated carcass surfaces increased from 1.2% to 95.7%, whereas the mean contamination on contaminated surfaces decreased from 1 logCFU/cm² to ?0.87 logCFU/cm², and the standard deviations decreased from 0.65 to 0.19. These results are explained by the fact that, due to carcass manipulations with hands, knives, and hooks, including the cutting of contaminated lymph nodes, Salmonella is transferred to previously uncontaminated carcasses, but in small quantities. These small quantities can easily go undetected during sampling. Sensitivity analyses gave insight into the model performance and showed that the touching and cutting of lymph nodes during inspection can be an important source of carcass contamination. The model can serve as a tool to support discussions on the modernization of pig carcass inspection. 相似文献
123.
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
124.
针对我国目前社会服务供给主体发展现状和社会服务供给特性,结合市场集中度和集约化管理理论,分析我国社会服务供给主体存在的主要问题,论述社会服务供给市场集中度与社会服务供给集约化的关系,提出通过降低准入门槛、鼓励主体竞合、强化规模运营、培育大型主体、理顺主体关系、完善竞争机制及优化市场结构等策略与措施,来推动社会服务供给集约化管理。 相似文献
125.
Junko Kawahara Shigeho Tanaka Chiaki Tanaka Yasunobu Aoki Junzo Yonemoto 《Risk analysis》2012,32(9):1595-1604
Lack of data on daily inhalation rate and activity of children has been an issue in health risk assessment of air pollutants. This study aimed to obtain the daily inhalation rate and intensity and frequency of physical activity in relation to the environment in Japanese preschool children. Children aged four–six years (n= 138) in the suburbs of Tokyo participated in this study, which involved three days' continuous monitoring of physical activity using a tri‐axial accelerometer and parent's completion of a time/location diary during daily life. The estimated three‐day mean daily inhalation rate (body temperature, pressure, saturated with water vapor) was 9.9 ± 1.6 m3/day (0.52 ± 0.09 m3/kg/day). The current daily inhalation rate value of 0.580 m3/kg/day proposed for use in health risk assessment in Japan is confirmed to be valid to calculate central value of inhaled dose of air pollutants in five‐ to six‐year‐old children. However, the 95th percentile daily inhalation rate of 0.83 m3/kg/day based on measurement for five‐year‐old children is recommended to be used to provide an upper bound estimate of exposure that ensure the protection of all five‐ to six‐year‐old children from the health risk of air pollutants. Children spent the majority of their time in sedentary and light level of physical activity (LPA) when indoors, while 85% of their time when outdoors was spent in LPA and moderate‐to‐vigorous physical activity. The results suggest the need to consider variability of minute respiratory ventilation rate according to the environment for more refined short‐term health risk assessment. 相似文献
126.
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
127.
Child‐caregiver Attachment Representations in a Non‐Western Context: The Feasibility and Cultural Equivalence of Story Stems in Urban Ghana 下载免费PDF全文
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
128.
Using In Vitro High‐Throughput Screening Data for Predicting Benzo[k]Fluoranthene Human Health Hazards 下载免费PDF全文
Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high‐throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline‐based meta‐regression can be used to integrate data across multiple assay replicates to generate a concentration–response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk‐specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta‐regression, may allow risk assessors to identify points of departure and risk‐specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods. 相似文献
129.
David Jiménez-Castillo 《Journal of Public Relations Research》2016,28(5-6):268-281
Despite the significance of relationship management in any information provision or exchange, public relations scholarship has typically focused on examining the underlying internal communication processes from a transactional perspective. These processes are frequently associated with organizational information dissemination, overlooking other critical contents to make strategic decisions. This study draws market information processing into the debate about internal communication, providing a greater understanding of how a relational approach can improve market intelligence dissemination. Results show that an effective management of market knowledge requires the use of such an approach, which in turn, cultivates the shared interpretation of market information and innovation performance. The findings stimulate fresh discussion about the nature and development of internal communication knowledge and practice. 相似文献
130.
We propose a family of goodness-of-fit tests for copulas. The tests use generalizations of the information matrix (IM) equality of White and so relate to the copula test proposed by Huang and Prokhorov. The idea is that eigenspectrum-based statements of the IM equality reduce the degrees of freedom of the test’s asymptotic distribution and lead to better size-power properties, even in high dimensions. The gains are especially pronounced for vine copulas, where additional benefits come from simplifications of score functions and the Hessian. We derive the asymptotic distribution of the generalized tests, accounting for the nonparametric estimation of the marginals and apply a parametric bootstrap procedure, valid when asymptotic critical values are inaccurate. In Monte Carlo simulations, we study the behavior of the new tests, compare them with several Cramer–von Mises type tests and confirm the desired properties of the new tests in high dimensions. 相似文献