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101.
To protect and secure food resources for the United States, it is crucial to have a method to compare food systems’ criticality. In 2007, the U.S. government funded development of the Food and Agriculture Sector Criticality Assessment Tool (FASCAT) to determine which food and agriculture systems were most critical to the nation. FASCAT was developed in a collaborative process involving government officials and food industry subject matter experts (SMEs). After development, data were collected using FASCAT to quantify threats, vulnerabilities, consequences, and the impacts on the United States from failure of evaluated food and agriculture systems. To examine FASCAT's utility, linear regression models were used to determine: (1) which groups of questions posed in FASCAT were better predictors of cumulative criticality scores; (2) whether the items included in FASCAT's criticality method or the smaller subset of FASCAT items included in DHS's risk analysis method predicted similar criticality scores. Akaike's information criterion was used to determine which regression models best described criticality, and a mixed linear model was used to shrink estimates of criticality for individual food and agriculture systems. The results indicated that: (1) some of the questions used in FASCAT strongly predicted food or agriculture system criticality; (2) the FASCAT criticality formula was a stronger predictor of criticality compared to the DHS risk formula; (3) the cumulative criticality formula predicted criticality more strongly than weighted criticality formula; and (4) the mixed linear regression model did not change the rank‐order of food and agriculture system criticality to a large degree.  相似文献   
102.
Injection drug users are at high risk for homelessness and human immunodeficiency virus (HIV) infection. This study sought to examine incidence rates and the social and economic antecedents of homelessness of impoverished inner-city injection drug users. Of the 569 participants, from a nontreatment sample who participated HIV prevention study, interviewed at baseline, 324 (57%) were reinterviewed 5.2 months later. At baseline 48% of the participants reported that they had been homeless in the past 10 years. Of the 324, 18% reported that at both interviews they had been homeless within the prior 6 months, 12% reported homelessness at baseline but not at follow-up, and 8% reported homelessness at follow-up but not at baseline. At baseline personal social support network characteristic of size of material aid and size of sex network was found to be associated with self-reports of homelessness. Baseline reports of presence of mother in personal network, size of material aid network, and network density were found to be associated with reports of homelessness at follow-up. These result suggest the need for alternative approaches to addressing issues of homelessness injection drug users.  相似文献   
103.
As Allport (1954) implied, the content of stereotypes may be systematic, and specifically, ambivalent. We hypothesize two clusters of outgroups, one perceived as incompetent but warm (resulting in paternalistic prejudice) and one perceived as competent but not warm (resulting in envious prejudice). Perceived group status predicts perceived competence, and perceived competition predicts perceived (lack of) warmth. Two preliminary surveys support these hypotheses for 17 outgroups. In-depth analyses of prejudice toward particular outgroups support ambivalent prejudice: Paternalistic prejudice toward traditional women, as well as envious prejudice toward career women, results in ambivalent sexism (Glick & Fiske, 1996). Envious prejudice toward Asians results in perceived competence but perceived lack of social skills. Ambivalent content reflects systematic principles.  相似文献   
104.
This paper examines effects of tacit and codified knowledge on performance improvement as organizations gain experience with a new technology. We draw from knowledge management and learning curve research to predict improvement rate heterogeneity across organizations. We first note that the same technology can present opportunities for improvement along more than one dimension, such as efficiency and breadth of use. We compare improvement for two dimensions: one in which the acquisition of codified knowledge leads to improvement and another in which improvement requires tacit knowledge. We hypothesize that improvement rates across organizations will be more heterogeneous for dimensions of performance that rely on tacit knowledge than for those that rely on codified knowledge (H1), and that group membership stability predicts improvement rates for dimensions relying on tacit knowledge (H2). We further hypothesize that when performance relies on codified knowledge, later adopters should improve more quickly than earlier adopters (H3). All three hypotheses are supported in a study of 15 hospitals learning to use a new surgical technology. Implications for theory and practice are discussed.  相似文献   
105.
In organ transplantation, placebo-controlled clinical trials are not possible for ethical reasons, and hence non-inferiority trials are used to evaluate new drugs. Patients with a transplanted kidney typically receive three to four immunosuppressant drugs to prevent organ rejection. In the described case of a non-inferiority trial for one of these immunosuppressants, the dose is changed, and another is replaced by an investigational drug. This test regimen is compared with the active control regimen. Justification for the non-inferiority margin is challenging as the putative placebo has never been studied in a clinical trial. We propose the use of a random-effect meta-regression, where each immunosuppressant component of the regimen enters as a covariate. This allows us to make inference on the difference between the putative placebo and the active control. From this, various methods can then be used to derive the non-inferiority margin. A hybrid of the 95/95 and synthesis approach is suggested. Data from 51 trials with a total of 17,002 patients were used in the meta-regression. Our approach was motivated by a recent large confirmatory trial in kidney transplantation. The results and the methodological documents of this evaluation were submitted to the Food and Drug Administration. The Food and Drug Administration accepted our proposed non-inferiority margin and our rationale.  相似文献   
106.
This article introduces the second issue of the special double issue focusing on forensic, cultural, and systems issues in child sexual abuse cases. We briefly review the articles, which include a discussion of child sexual abuse myths, an empirical analysis of extended child sexual abuse evaluations, an article on the role of the medical provider in child sexual abuse evaluations, a study of satisfaction levels with multidisciplinary teams in child advocacy centers, and a commentary advocating for the credentialing of forensic interviewers. We call for further empirical examination of media related to child sexual abuse risk, research on appropriate models for extended sexual abuse interviews and evaluations, and optimal practices relevant to each member of multidisciplinary teams in a child advocacy center.  相似文献   
107.
Alcoholic beverage consumption among high school students has shifted from beer to liquor. The current longitudinal study examined the effects of beverage-specific alcohol use on drinking behaviors among urban youth. Data included 731 adolescents who participated in Project Northland Chicago and reported consuming alcohol in 7th grade. Logistic regression tested the effects of beverage-specific use on consequences (e.g., alcohol use in the past month, week, heavy drinking, and ever drunkenness). Compared to wine users, adolescents who reported drinking hard liquor during their last drinking occasion had increased odds of alcohol use during the past month (OR = 1.44; 95% CI = 1.01-2.05), past week (OR = 3.37; 95% CI = 1.39-8.18), and ever drunkenness (OR = 1.56; 95% CI = 1.07-2.29). Use of hard liquor was associated with increased risk of alcohol-related consequences. Early selection of certain alcoholic beverages (e.g., hard liquor) may result in negative health outcomes and problematic alcohol use over time.  相似文献   
108.
ABSTRACT

The purpose of this groundbreaking study was to evaluate outcomes of 482 LGBTQ (lesbian, gay, bisexual, transgender, or questioning) youth and young adults who received services and supports through the Comprehensive Community Mental Health Services for Children with Serious Emotional Disturbances Program (CMHI). This study was a secondary data analysis using data from a larger study of 3208 LGBTQ and non-LGBTQ youth ages 11 through 21 who had a serious emotional disturbance (SED). This study is significant in that it evaluates functional outcomes for young people identified as LGBTQ based on a specialized service framework (i.e., system of care approach). In essence, do LGBTQ youth with SED benefit from a specific approach to intervention? In addition, a comparison at intake on suicidality, bullying and victimization was conducted between the LGBTQ and non-LGBTQ identifying youth from the larger sample. The youth and a caregiver were interviewed face-to-face separately at intake, 6-months, and 12-months. Significant improvements were found across all of the dependent variables, supporting the viability of SOC for improving outcomes for LGBTQ youth. Future research should continue to build on this study by adding to the design a control group to improve internal validity of the findings.  相似文献   
109.
SiZer (SIgnificant ZERo crossing of the derivatives) is a graphical scale-space visualization tool that allows for statistical inferences. In this paper we develop a spatial SiZer for finding significant features and conducting goodness-of-fit tests for spatially dependent images. The spatial SiZer utilizes a family of kernel estimates of the image and provides not only exploratory data analysis but also statistical inference with spatial correlation taken into account. It is also capable of comparing the observed image with a specific null model being tested by adjusting the statistical inference using an assumed covariance structure. Pixel locations having statistically significant differences between the image and a given null model are highlighted by arrows. The spatial SiZer is compared with the existing independent SiZer via the analysis of simulated data with and without signal on both planar and spherical domains. We apply the spatial SiZer method to the decadal temperature change over some regions of the Earth.  相似文献   
110.
Abstract

Objective: To assess the perceptions and practices of a national sample of college and university presidents regarding their support for concealed handguns being carried on college campuses. Participants: The sample for this study consisted of a national random sample of 900 college or university presidents. Methods: In the spring of 2013, a 3-wave mailing procedure was used to ensure an adequate response rate to a valid and reliable questionnaire. Results: The response rate was 46%, more than what was needed based on the power analysis. The vast majority (95%) of respondents were not supportive of carrying concealed handguns on campuses. They perceived there to be more disadvantages than advantages to handguns on campus. However, college administrators were not focused enough on the primary prevention of campus firearm trauma. Conclusions: The findings of this study suggest a number of activities that could be implemented to enhance safety on college and university campuses.  相似文献   
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