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991.
Effect of Climate Change on the Concentration and Associated Risks of Vibrio Spp. in Dutch Recreational Waters 下载免费PDF全文
Ankie Sterk Franciska M. Schets Ana Maria de Roda Husman Ton de Nijs Jack F. Schijven 《Risk analysis》2015,35(9):1717-1729
Currently, the number of reported cases of recreational‐ water‐related Vibrio illness in the Netherlands is low. However, a notable higher incidence of Vibrio infections has been observed in warm summers. In the future, such warm summers are expected to occur more often, resulting in enhanced water temperatures favoring Vibrio growth. Quantitative information on the increase in concentration of Vibrio spp. in recreational water under climate change scenarios is lacking. In this study, data on occurrence of Vibrio spp. at six different bathing sites in the Netherlands (2009–2012) were used to derive an empirical formula to predict the Vibrio concentration as a function of temperature, salinity, and pH. This formula was used to predict the effects of increased temperatures in climate change scenarios on Vibrio concentrations. For Vibrio parahaemolyticus, changes in illness risks associated with the changed concentrations were calculated as well. For an average temperature increase of 3.7 °C, these illness risks were calculated to be two to three times higher than in the current situation. Current illness risks were, varying per location, on average between 10?4 and 10?2 per person for an entire summer. In situations where water temperatures reached maximum values, illness risks are estimated to be up to 10?2 and 10?1. If such extreme situations occur more often during future summers, increased numbers of ill bathers or bathing‐water‐related illness outbreaks may be expected. 相似文献
992.
This article describes the results of a qualitative case study evaluating a research mentorship program in community care settings in Ontario, Canada. The purpose of the program was to build evaluation and research capacity among staff of community care agencies through a mentorship program. Data were collected through in-depth, semi-structured interviews, focus group interviews, and written evaluations. Three themes were identified: taking hold, fostering hold, and holding on. Mentees took hold of new evaluation and research skills. Factors fostering hold included positive mentoring relationships and participation in relevant research projects. Mentees struggled to hold on to, and apply their skills within a community care context of challenges such as constrained resources and a mandate to provide client-centered care. The lessons learned include having trainees participate in relevant, time-limited evaluation and research projects, and early implementation of mechanisms to sustain integration of trainees' knowledge and skills within community care agencies. 相似文献
993.
This study examines whether place of residence is a factor associated with reporting a positive HIV/AIDS, Hepatitis C (HCV), or Sexually Transmitted Disease (STD) status in a sample of 400 injection drug users (IDUs) residing on the Island of Puerto Rico (N=139) and in western Massachusetts (N=261). Logistic regression models revealed that IDUs residing in western Massachusetts were 66% less likely to be HIV positive compared to IDUs residing in Puerto Rico (p<.000) while IDUs residing in western Massachusetts were about 67% less likely to have a positive STD status than those residing in Puerto Rico (p<.000). Place of residence was not significantly associated with HCV status. Results indicate the need to develop prevention programs tailored to the unique socio-cultural context of Puerto Rican IDUs residing on the Island of Puerto Rico whose circumstances differ from those in the mainland US. To reduce drug use, HIV/AIDS, HCV, and STDs among Puerto Ricans in both locales, the Capacity Enhancement Model is proposed in order to develop more effective prevention programs. 相似文献
994.
995.
Research was conducted investigating university students' prejudicial attitudes toward bisexual men and women in South Africa. The combined male and female Attitudes Regarding Bisexuality Scale (ARBS) showed unacceptable internal consistency reliabilities, especially for the Black-African participants. An expert focus group was convened in order to elaborate on and clarify the low reliability coefficients. The ARBS was then adapted for the South African population and resulted in two separate instruments designed to measure attitudes regarding bisexual men and bisexual women separately. Five hundred eighty seven university students completed these scales. The results indicated that the attitudes of heterosexual, homosexual, and asexual students toward bisexual men and women are more negative than the attitudes of bisexual students. 相似文献
996.
Annibal Parracho Sant’Anna Rodrigo Otávio de Araújo Ribeiro Steven Dutt-Ross 《Social indicators research》2011,104(3):523-532
A new form of composition of the indicators employed to generate the United Nations Human Development Index (HDI) is presented
here. This form of composition is based on the assumption that random errors affect the measurement of each indicator. This
assumption allows for replacing the vector of evaluations according to each indicator by vectors of probabilities of being
the best or the worst according to such attribute. The probabilistic composition of such probabilities of preference according
to each indicator into probabilities of being the best or the worst according to all of them generates indices that may unveil,
on one hand, performances to be followed and, on the other hand, extreme conditions that an additive composition would hide.
Differences between the results of application of the diverse forms of composition are examined in the case of the HDI and
in the case of the districts version of the HDI employed to compare Brazilian municipalities. It is verified that the smallest
correlation between the education enrolment rate and the other indicators in the Brazilian case enlarges such differences. 相似文献
997.
Stepping stones for the unemployed: the effect of temporary jobs on the duration until (regular) work 总被引:1,自引:0,他引:1
Marloes de Graaf-Zijl Gerard J. van den Berg Arjan Heyma 《Journal of population economics》2011,24(1):107-139
Transitions from unemployment into temporary work are often succeeded by a transition from temporary into regular work. This
paper investigates whether temporary work increases the transition rate to regular work. We use longitudinal survey data of
individuals to estimate a multi-state duration model, applying the ‘timing of events’ approach. The data contain multiple
spells in labour market states at the individual level. We analyse results using novel graphical representations, which unambiguously
show that temporary jobs shorten the unemployment duration, although they do not increase the fraction of unemployed workers
having regular work within a few years after entry into unemployment. 相似文献
998.
Darren E. Sherkat Melissa Powell-WilliamsGregory Maddox Kylan Mattias de Vries 《Social science research》2011,40(1):167-180
We examine how religious and political factors structure support for same-sex marriage in the United States over the last two decades. Using data from the General Social Surveys, we show that respondents who identify more strongly with the Republican Party, sectarian denominations, and those who subscribe to biblical fundamentalism and political conservatism are substantially more opposed to same-sex marriage than are other Americans. Heterogeneous ordinal logistic regression models show that these religious and political factors have become more important over the last two decades. Cohorts born after 1945 became substantially more supportive of marriage rights between 1988 and 2008, but shifts in support for marriage rights were less sizeable for persons affiliated with sectarian denominations, religious fundamentalists, Republicans, and political conservatives. Estimates from structural equation models show that religious factors influence political conservatism and Republican identification, yet both religious and political factors have significant and substantial independent direct effects on support for same-sex marriage. 相似文献
999.
Han-Ying Liang Jacobo de Uña-Álvarez 《Journal of statistical planning and inference》2011,141(11):3475-3488
In this paper, the empirical likelihood method is used to define a new estimator of conditional quantile in the presence of auxiliary information for the left-truncation model. The asymptotic normality of the estimator is established when the data exhibit some kind of dependence. It is assumed that the lifetime observations with multivariate covariates form a stationary α‐mixing sequence. The result shows that the asymptotic variance of the proposed estimator is not larger than that of standard kernel estimator. Finite sample behavior of the estimator is investigated via simulations too. 相似文献
1000.
K. M. A. de Souza J. T. Kent & K. V. Mardia 《Journal of the Royal Statistical Society. Series C, Applied statistics》1999,48(2):211-227
A general statistical approach is presented for the identification of objects in digital images, motivated by an application in aquaculture involving underwater images of fish. Using Procrustes analysis, a point distribution model is fitted on a set of training images and used as a prior distribution for the shape of a deformable template. The likelihood of a proposed template is calculated in terms of the response from a feature detector along the boundary of the template. The posterior distribution of template variables is examined by using Markov chain Monte Carlo analysis. A key challenge in the aquaculture application is the variable nature of edges arising from the surface curvature of fish and the low contrast between the foreground and background. Conventional gradient-based edge detection proves inadequate, but a parallel pattern detector copes much better. Results are presented for a fully automated analysis of the database. The strengths and weaknesses of this approach are discussed and future developments are outlined. 相似文献