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831.
832.
Recreational and subsistence angling are important aspects of urban culture for much of North America where people are concentrated near the coasts or major rivers. Yet there are fish and shellfish advisories for many estuaries, rivers, and lakes, and these are not always heeded. This paper examines fishing behavior, sources of information, perceptions, and compliance with fishing advisories as a function of ethnicity for people fishing in the Newark Bay Complex of the New York–New Jersey Harbor. We test the null hypothesis that there were no ethnic differences in sources of information, perceptions of the safety of fish consumption, and compliance with advisories. There were ethnic differences in consumption rates, sources of information about fishing, knowledge about the safety of the fish, awareness of fishing advisories or of the correct advisories, and knowledge about risks for increased cancer and to unborn and young children. In general, the knowledge base was much lower for Hispanics, was intermediate for blacks, and was greatest for whites. When presented with a statement about the potential risks from eating fish, there were no differences in their willingness to stop eating fish or to encourage pregnant women to stop. These results indicate a willingness to comply with advisories regardless of ethnicity, but a vast difference in the base knowledge necessary to make informed risk decisions about the safety of fish and shellfish. Although the overall median income level of the population was in the $25,000–34,999 income category, for Hispanics it was on the border between $15,000–24,999 and $25,000–34,999.  相似文献   
833.
When Shannon entropy is used as a criterion in the optimal design of experiments, advantage can be taken of the classical identity representing the joint entropy of parameters and observations as the sum of the marginal entropy of the observations and the preposterior conditional entropy of the parameters. Following previous work in which this idea was used in spatial sampling, the method is applied to standard parameterized Bayesian optimal experimental design. Under suitable conditions, which include non-linear as well as linear regression models, it is shown in a few steps that maximizing the marginal entropy of the sample is equivalent to minimizing the preposterior entropy, the usual Bayesian criterion, thus avoiding the use of conditional distributions. It is shown using this marginal formulation that under normality assumptions every standard model which has a two-point prior distribution on the parameters gives an optimal design supported on a single point. Other results include a new asymptotic formula which applies as the error variance is large and bounds on support size.  相似文献   
834.
835.
This article describes a Delphi‐based expert judgment study aimed at the selection of indicators to identify the occurrence of emerging mycotoxin hazards related to Fusarium spp. in wheat supply chains. A panel of 29 experts from 12 European countries followed a holistic approach to evaluate the most important indicators for different chain stages (growth, transport and storage, and processing) and their relative importance. After three e‐mailing rounds, the experts reached consensus on the most important indicators for each of the three stages: wheat growth, transport and storage, and processing. For wheat growth, these indicators include: relative humidity/rainfall, crop rotation, temperature, tillage practice, water activity of the kernels, and crop variety/cultivar. For the transport and storage stage, they include water activity in the kernels, relative humidity, ventilation, temperature, storage capacity, and logistics. For wheat processing, indicators include quality data, fraction of the cereal used, water activity in the kernels, quality management and traceability systems, and carryover of contamination. The indicators selected in this study can be used in an identification system for the occurrence of emerging mycotoxin hazards in wheat supply chains. Such a system can be used by risk managers within governmental (related) organizations and/or the food and feed industry in order to react proactively to the occurrence of these emerging mycotoxins.  相似文献   
836.
Resumen

Se propone un acercamiento socio-construccionista para el estudio de las subjetividades de género sexual frente al tratamiento cognitivista y sociocognitivista, dominantes en Psicología Social, en la investigación sobre identidad sexual, estereotipos y categorías de género. Asimismo se parte de ciertos planteamientos provenientes de la epistemología feminista postmoderna que ponen un énfasis especial en el análisis del lenguaje como instrumento mediatizador, regulador y modelador de la subjetividad y el género desde una perspectiva de las relaciones de poder y su regulación de subjetividades. Desde este triple marco el objetivo es analizar si la subjetividad de género femenino, supuestamente heredada y compartida según la mayoría de estudios de estereotipos, modela las identificaciones de las propias mujeres o si éstas desarrollan formas de resistencia hacia ella. Por todo ello la metodología de Análisis del Discurso aparece como la estrategia de investigación más adecuada. Los resultados del Análisis del Discurso de las narraciones de las mujeres sobre ellas mismas pone de manifiesto distintas subjetividades con diferentes niveles de agencia en relación a la reproducción o transformación de la escisión de género femenino.  相似文献   
837.
The author examines a case from a qualitative research study exploring repetition-compulsion and repair in consensual sadomasochistic/dominant-submissive (SMDS) sexual play. The study attempts to bridge the epistemological divide between clinically derived psychoanalytic theories about perversion and nonclinical research on consensual SMDS subcultures. The case addresses research questions about the presence of, and possibilities for, working through childhood developmental conflicts in consensual SMDS (as theoretically differentiated from its nonconsensual counterparts).

This study, along with those theories that uproot classical notions of sexuality and the “oedipal divide,” lends support for the view that the diversity of lived and practiced sexualities defies facile categorization and that, if categorization is to be attempted, it must take into account individual meanings and relational/larger social contexts.  相似文献   
838.
Delta areas like the Netherlands are threatened by global climate change. Awareness is, however, rather low. Our research objective was to investigate whether coping responses to flooding risks could be enhanced in a virtual environment (VE). A laboratory experiment was conducted in which participants were exposed to a simulated dike breach and consequent flooding of their virtual residence. We tested the hypothesis that an interactive 3D flood simulation facilitates coping responses compared to noninteractive film and slide simulations. Our results showed that information search, the motivation to evacuate, and the motivation to buy flood insurance increased after exposure to the 3D flood simulation compared to the film and slide simulations. Mediation analyses revealed that some of these presentation mode effects were mediated by a greater sense of being present in the VE. Implications to use high‐end flood simulations in a VE to communicate real‐world flooding risks and coping responses to threatened residents will be discussed.  相似文献   
839.
The mean absolute deviation (MAD) estimator has recently received a great deal of attention as applied to full-rank linear regression models. This paper provides a necessary and sufficient condition for the MAD estimator to be a non-linear estimator, in which case conditions for the variance of the MAD estimator to be larger or smaller than those for OLS are, in general, unknown. The non-linearity of the MAD estimator is examined for several two-way designs; in particular (1) randomized block design (2) two-way nested design (3) two-way classification with interaction and (4) partially balanced incomplete block design  相似文献   
840.
This study tested the effects of a 2-day team building intervention on team members’ team identification, social support and collective self-efficacy. Members (n?=?32) of three teams from different sectors completed questionnaires before, directly after and six weeks after the team building intervention. Two teams served as control groups. Results showed lasting positive effects of team building on identification, support and collective self-efficacy in the training groups but no changes in the control groups.  相似文献   
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