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971.
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
972.
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
973.
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
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975.
976.
F. Chang 《统计学通讯:模拟与计算》2013,42(5):1104-1114
Optimal designs for estimating the parameters and also the optimum factor combinations in multiresponse experiments have been considered by various authors. However, till date, in mixture experiments optimum designs have been studied only in the single response case. In this article, attempt has been made to investigate optimum designs for estimating optimum mixing proportions in a multiresponse mixture experiment. 相似文献
977.
John E. Angus 《统计学通讯:模拟与计算》2013,42(4):1307-1331
In many engineering problems it is necessary to draw statistical inferences on the mean of a lognormal distribution based on a complete sample of observations. Statistical demonstration of mean time to repair (MTTR) is one example. Although optimum confidence intervals and hypothesis tests for the lognormal mean have been developed, they are difficult to use, requiring extensive tables and/or a computer. In this paper, simplified conservative methods for calculating confidence intervals or hypothesis tests for the lognormal mean are presented. In this paper, “conservative” refers to confidence intervals (hypothesis tests) whose infimum coverage probability (supremum probability of rejecting the null hypothesis taken over parameter values under the null hypothesis) equals the nominal level. The term “conservative” has obvious implications to confidence intervals (they are “wider” in some sense than their optimum or exact counterparts). Applying the term “conservative” to hypothesis tests should not be confusing if it is remembered that this implies that their equivalent confidence intervals are conservative. No implication of optimality is intended for these conservative procedures. It is emphasized that these are direct statistical inference methods for the lognormal mean, as opposed to the already well-known methods for the parameters of the underlying normal distribution. The method currently employed in MIL-STD-471A for statistical demonstration of MTTR is analyzed and compared to the new method in terms of asymptotic relative efficiency. The new methods are also compared to the optimum methods derived by Land (1971, 1973). 相似文献
978.
979.
1. Postpartum depression has been used as a catchall phase for many postpartum emotional symptoms. Categorizing a number of diverse disorders under one title has resulted in an inability to identify who is most at risk for developing postpartum problems. 2. The postpartum period is a particularly vulnerable period for depression, despite the fact that it is perceived as a time of joy and emotional well-being. 3. By increasing awareness among all health care professionals who care for women during the period following childbirth, postpartum psychiatric disorders can be identified early and treated correctly. 4. Limiting postpartum psychiatric disorders to postpartum depression may result in limited or inappropriate treatment options. 相似文献
980.
We examined the contribution of relational aggression in adolescents' peer and dating relationships to their psychological and behavioral adjustment. In the Fall and again four months later, 1279 (646 female) grade 9 students reported on relational aggression perpetration and victimization in their romantic and peer relationships, depression/anxiety symptoms (psychological adjustment) and delinquency (behavioral adjustment). Using hierarchical regression analyses, controlling for Time 1 adjustment/behavior, peer relational aggression perpetration predicted depression/anxiety. Dating relational victimization also predicted depression/anxiety, but only for girls. Furthermore, girls who were perpetrators of relational aggression in both peer and dating contexts were most likely to show increases in delinquent behavior. We conclude that dating and peer relationships are not redundant, but make independent and additive contributions to adolescent adjustment. Girls, in particular, may be at greatest risk for poor outcomes when they have relationally aggressive relationships. Results also highlight the need for greater awareness of the complexity and significance of adolescent dating relationships. 相似文献