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981.
Larry L. Lawson Jr. Jeffrey E. Hill Lorenzo Vilizzi Scott Hardin Gordon H. Copp 《Risk analysis》2013,33(8):1414-1431
The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate‐zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species. 相似文献
982.
Jon E. Grant JD MD MPH Brian L. Odlaug MPH Katherine Derbyshire BS Liana R. N. Schreiber BA Katherine Lust PhD MPH Gary Christenson MD 《Journal of American college health : J of ACH》2013,61(1):75-78
Abstract Objective: This study examined the prevalence of mental health disorders and their clinical correlates in a university sample of lesbian, gay, bisexual, and queer (LGBQ) students. Participants: College students at a large public university. Methods: An anonymous, voluntary survey was distributed via random e-mail generation to university students during April and May of 2011. LGBQ students were compared with their heterosexual counterparts on psychological and physical status as well as academic performance. Results: LGBQ students reported worse depressive symptoms, higher levels of perceived stress, considered themselves less attractive, and were more likely to be overweight. LGBQ students were significantly more likely to report histories of affective, substance use, and certain anxiety disorders as well as compulsive sexual behavior and compulsive buying. Conclusions: The higher rates of many psychiatric conditions among LGBQ students underscore the need for universities to provide LGBQ students a nonjudgmental environment to discuss sexual orientation and health issues. 相似文献
983.
This paper considers a likelihood ratio test for testing hypotheses defined by non-oblique closed convex cones, satisfying the so called iteration projection property, in a set of k normal means. We obtain the critical values of the test using the Chi-Bar-Squared distribution. The obtuse cones are introduced as a particular class of cones which are non-oblique with every one of their faces. Examples with the simple tree order cone and the total order cone are given to illustrate the results. 相似文献
984.
Over the last 40 years, the Sahel has seen a long-term downward trend in rainfall. The importance of ecological variables as factors affecting child survival in rural subsistence societies has already been emphasized, but little empirical evidence has been gathered to support this. This paper presents a comparative event history analysis aimed at understanding how rainfall variations may influence child mortality in two neighbouring countries, Burkina Faso and Mali. These countries are similar in terms of population dynamics, economy, livelihood, child mortality and rainfall conditions (i.e. strong south–north decreasing rainfall gradient). Individual data for both countries came from two detailed nationally representative retrospective surveys conducted in 2000. Rainfall data for the 1960–1998 time period were obtained from the Climatic Research Unit. This study shows that child survival in each country is related to specific patterns of rainfall variation across livelihood regions, highlighting the complex nature of environmental causality of child mortality. 相似文献
985.
Motion picture performance: A review and research agenda 总被引:1,自引:0,他引:1
Allègre L. Hadida 《国际管理评论杂志》2009,11(3):297-335
This paper provides a comprehensive literature review of empirical studies of motion picture performance published from 1977 to 2006 inclusive in the following five disciplines of the social sciences: strategy, organization theory, marketing, cultural economics and sociology. It introduces a novel framework which organizes the various dimensions and explanatory factors of movie performance into five distinct categories and underscores their relationships. The paper, which uses this model as a roadmap for discussions of film success, serves two complementary purposes. First, it clarifies the current state of the literature, stresses core contributions and exposes limitations in existing research by emphasizing hitherto neglected independent explanatory factors, dependent dimensions and correlations between them. Second, it introduces five conceptual, methodological and empirical suggestions for further cinema performance research aimed at addressing these limitations and, accordingly, at providing better accounts of motion picture performance in view of the fast-changing conditions of cinema production, marketing and consumption. 相似文献
986.
Data on population trends in Russia show that despite fluctuations, the long-term trend is a continued decline in the size of the Russian population. The government's pro-fertility policies may not be able to stem this trend, and the potential for in-migration of people of Russian descent is almost exhausted. 相似文献
987.
988.
We know that inequality varies by region and also begins early in life. Bivariate data suggest that 5–14-year-old children in the 1994 National Longitudinal Survey of Youth (NLSY) score differently in reading and mathematics achievement depending on their region, with children in the South and West scoring lower. We combine literatures on regional bases of inequality and family and school capital to generate hypotheses explaining these differences. Analyses of covariance provide supportive evidence. For both outcomes among boys, the variation is explained by additive models including family and child social and human capital, although selected aspects of school capital are also influential; these models also explain math achievement among girls. A model including both additive and interactive effects explains regional differences in reading achievement for girls. We interpret these findings in terms of their implications for studying inequality in child achievement as well as for emphasizing the importance of regional inequality, particularly beyond the South versus non-South distinction. 相似文献
989.
Tammy L. Henderson Maria Sirois Angela Chia-Chen Chen Christopher Airriess David A. Swanson David Banks 《Population research and policy review》2009,28(1):67-92
In 2005, the National Science Foundation funded a number of projects to study the impact of Hurricane Katrina. The current
article provides an overview of several research approaches used to conduct post-Katrina research. Each method had some advantages
and disadvantages. The post-disaster context meant that experience from traditional survey methods often did not apply. Comparisons
of advantages and disadvantages associated with each sampling method serve to inform future post-disaster research and illuminate
the limits of classical research methods. 相似文献
990.
PD Dr. Sascha L. Schmidt Prof. Dr. Benno Torgler Prof. Dr. Dr. h.c. mult. Bruno S. Frey 《Zeitschrift für Betriebswirtschaft》2009,79(3):303-334
Relative income differences are likely to lead to envy within a reference group. Envy in turn influences social behavior and individual performance. While positional concerns are apparent in daily life, empirical evidence is rare in the economic literature. This paper investigates the impact of the relative income position on individuals’ performance or productivity. As ?performance“ is difficult to measure we turn to soccer players whose performance has been well documented. The broad sample covers eight seasons of the German premier soccer league (Bundesliga) between 1995 and 2004, and includes 1040 players, a salary proxy and several performance variables. The results show that player performance is strongly affected by relative income position. A disadvantage in the relative income position reduces productivity. The larger the income differences within a team, the stronger are the effects of positional concern. Team composition also significantly affects behaviour. 相似文献