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Identifying the source of polychlorinated biphenyls (PCBs) is the first step to eliminating contamination within anadromous salmonids and other aquatic species. We evaluated PCB concentrations in the muscle tissue of 4-year old Puget Sound and coastal hatchery Chinook salmon in an effortto identify potential locations where contamination occurs. Ten muscle samples were taken from each of two Puget Sound hatcheries and two coastal hatcheries in Washington State to determine PCB concentrations. Two technical mixtures of PCBs, Aroclor 1254 and Aroclor 1260, were measured in the tissue samples collected. Aroclor 1254 was detected in all samples, while Aroclor 1260 was detected in 16 of 40 samples. Generalized linear modeling (GLM) was used to evaluate the influence of region (Puget Sound and coast), hatchery, sex, fish length, and percent lipids on PCB concentrations. Twenty different GLMs representing multiple null hypotheses were ranked using Akaike Information Criterion (AIC). Six of the 20 models evaluated had substantial support for being the best model to describe PCB concentrations in Chinook salmon. The six models with substantial support were region and lipids; region; hatchery and lipid; region and sex; region, sex, and lipids; and region and length. Region appears to be the most influential variable explaining the variation in PCB concentrations in Chinook salmon in the Pacific Northwest. PCB concentrations in Chinook salmon muscle tissue from Puget Sound hatcheries were significantly greater (mean 49.26 microg/kg wet weight and standard deviation 40.55 microg/kg) than those from coastal hatcheries (mean 17.41 microg/kg wet weight and standard deviation 6.8 microg/kg). Our results suggest that some contamination likely occurs in the Pacific Ocean. However, a larger source likely exists within Puget Sound or along the migratory route of Puget Sound Chinook salmon. The observation of PCBs in Chinook salmon also has important implications for human health and salmon carcass supplementation.

The Strain Index is one of several tools available to evaluate exposure to musculoskeletal stressors in the workplace in order to predict whether workers are at an increased risk of developing distal upper extremity disorders. The purpose of this study was to determine the inter-rater reliability of the Strain Index. Fifteen raters initially estimated or measured data for five Strain Index task variables: (1) intensity of exertion, (2) duration of exertion, (3) efforts per minute, (4) hand/wrist posture, and (5) speed of work, using a computer to view 61 video segments of single task jobs. Video segments were organized to provide a balanced number for each of the five variables under study, where each segment was used to provide data for a single variable. Raters then assigned rating values to each task according to published procedures. For an additional 12 segments, raters performed complete Strain Index analyses, including calculation of Strain Index scores, which were used to determine hazard classifications. Raters assessed the tasks both as individuals and as members of five three-person teams. Inter-rater reliabilities of the procedures leading to and including the Strain Index scores were assessed using an intraclass correlation coefficient, (ICC(2, 1)). Inter-rater reliability for the dichotomous hazard classification was assessed using Kuder-Richardson-20 (KR-20, an ICC for dichotomous data). For task variables and estimated data, ICC(2, 1) varied between 0.66-0.84 for individuals and 0.48-0.93 for teams. The Strain Index score had an ICC(2, 1) of 0.43 and 0.64 for individuals and teams, respectively. For the most important variable, hazard classification, KR-20 was 0.91 for the individuals and 0.89 for the teams.

This study examined the differences in attitudes toward science education among American, Chinese-American, and Chinese parents and students. Parents' expectations for their high school children's science performance were also compared among the three cultural groups. It was found that both Chinese parents and students had more positive attitudes toward science education than did their American counterparts. Chinese parents placed greater emphasis on self-improvement, set higher standards, and more often helped their children to learn science than did American parents. The attitudes of the Chinese-Americans appeared to show the influences of both their Chinese heritage and American culture. Overall, a high positive correlation was found between parents' and students' attitudes toward science education.

Cultural background not only influences family beliefs about the value of education, but may affect how academic expectations are communicated by parents and perceived by their children. This study examined differences in willingness to conform to parents' expectations of academic achievement as perceived by American, Chinese-American, and Chinese high school students. Findings indicated that Chinese students were more willing to accept their parents' advice and cared more about fulfilling academic expectations than did American students. Students in all three groups had similar feelings of independence. The views of Chinese-American students reflected the influence of both their Chinese heritage and the American culture in which they resided.

Estimates of the incidence of laxative abuse in bulimics and in the community-at-large vary widely for various population samples. This review identified 73 studies in which laxative abuse could be assessed in bulimics, nonbulimics, and the community-at-large. Relative risk values for laxative abuse among population subsamples were estimated by moment methods statistical procedure based on mixed model analysis. Results indicated that the lifetime occurrence for laxative abuse behavior in the community-at-large was 4.18%. Bulimic behavior increased the risk for laxative abuse 3.57-fold to 14.94%. Several methodologic and population parameter characteristics are examined for their select impact on laxative abuse. Review of medical nomenclature for classifying laxative substances, iatragenic effects of laxative abuse, and assessment recommendations are also included.

A Buberian perspective on problems related to the establishment of therapeutic environments on mental hospital wards is offered. Depersonalization and over-reliance on a medical treatment orientation in human relationships are identified as central problem areas in mental hospitals. The therapeutic community is identified as a major alternative model to respond to these problem areas. Difficulties in applying the therapeutic community model are identified. Buber's social philosophy, especially his interpretations of spiritual crisis, cultural crisis, structural renewal, and genuine dialogue, are identified as useful tools to clarify and resolve those difficulties.