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91.
Jeff D. Gamlin Jordan F. Clark Greg Woodside Roy Herndon 《Canadian Metallurgical Quarterly》2001,127(2):171-174
Sulfur hexafluoride (SF6) was injected into a 9 km reach of the Santa Ana River in Orange County, CA, over a period of two weeks. The entire flow of this river, which averaged 2.8 m3 s?1, percolated into the ground in the field area. The tracer was monitored at wells near the river to determine subsurface flow patterns and flow times with an accuracy much greater than could be achieved using numerical simulations of ground-water flow. During the experiment, SF6 effectively tagged 3.7 × 106 m3 of water. The tracer plume was mapped in the subsurface for 18 months and indicates that linear ground-water velocities averaged about 2 km year?1. The tracer reached two wells adjacent to the river (about 200 m away) within three weeks, giving evidence that SF6 was not retarded significantly relative to the ground-water flow. This is in agreement with previous laboratory experiments. 相似文献
92.
Design teams rarely consider multiple solution ideas before committing to one. They often forget that an even better idea could be just around the corner, and consider alternative ideas only when they don't like the current one. Using sketchboarding, design studio, or a combination of these two techniques can let teams quickly ideate over many solutions. They then have a chance to arrive at a solution that no one individual had thought of. 相似文献
93.
The traditional explanation for dual-task interference is that tasks compete for scarce processing resources. Another possible explanation is that the outcome of the processing required for one task conflicts with the processing required for the other task (e.g., cross talk). To explore the contribution of outcome conflict to task interference, we manipulated the relatedness of the tasks. In Experiment 1, subjects searched concurrently for names of boys in one channel and names of cities in another channel. Responses were significantly delayed when nontarget on one channel belonged to, or was even just related to, the category designated as the target for the other channel. No comparable effects were found when the tasks were performed in isolation. Thus, the difficulty of the individual tasks is not the only determinant of how much they will interfere when combined, and there must be substantial interactions between processes carrying out the two tasks. In Experiment 2 subjects searched one channel for specific target letters and another channel for specific target digits. The nontargets in a channel were either from the same alphanumeric category as the targets for that channel or from the opposite category (i.e., the category of the targets for the other channel). It was found that although between-category search was more efficient than within-category search in single tasks, it was less efficient in dual tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Wyman Peter A.; Brown C. Hendricks; Inman Jeff; Cross Wendi; Schmeelk-Cone Karen; Guo Jing; Pena Juan B. 《Canadian Metallurgical Quarterly》2008,76(1):104
Gatekeeper-training programs, designed to increase identification and referral of suicidal individuals, are widespread but largely untested. A group-based randomized trial with 32 schools examined impact of Question, Persuade, Refer (QPR) training on a stratified random sample of 249 staff with 1-year average follow-up. To test QPR impact, the authors introduced and contrasted 2 models of gatekeeper-training effects in a population: gatekeeper surveillance and gatekeeper communication. Intent-to-treat analyses showed that training increased self-reported knowledge (effect size [ES] = 0.41), appraisals of efficacy (ES = 1.22), and service access (ES = 1.07). Training effects varied dramatically. Appraisals increased most for staff with lowest baseline appraisals, and suicide identification behaviors increased most for staff already communicating with students about suicide and distress. Consistent with the communication model, increased knowledge and appraisals were not sufficient to increase suicide identification behaviors. Also consistent with the communication model were results from 2,059 8th and 10th graders surveyed showing that fewer students with prior suicide attempts endorsed talking to adults about distress. Skill training for staff serving as "natural gatekeepers" plus interventions that modify students' help-seeking behaviors are recommended to supplement universal gatekeeper training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Greenberg Jeff; Pyszczynski Tom; Solomon Sheldon; Rosenblatt Abram; Veeder Mitchell; Kirkland Shari; Lyon Deborah 《Canadian Metallurgical Quarterly》1990,58(2):308
Three experiments were conducted to test the hypothesis, derived from terror management theory, that reminding people of their mortality increases attraction to those who consensually validate their beliefs and decreases attraction to those who threaten their beliefs. In Study 1, subjects with a Christian religious background were asked to form impressions of Christian and Jewish target persons. Before doing so, mortality was made salient to half of the subjects. In support of predictions, mortality salience led to more positive evaluations of the in-group member (the Christian) and more negative evaluations of the out-group member (the Jew). In Study 2, mortality salience led to especially negative evaluations of an attitudinally dissimilar other, but only among subjects high in authoritarianism. In Study 3, mortality salience led to especially positive reactions to someone who directly praised subjects' cultural worldviews and especially negative reactions to someone who criticized them. The implications of these findings for understanding in-group favoritism, prejudice, and intolerance of deviance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
The author describes the process that led him to run for election to the Arizona State House of Representatives. His decision was more the result of an interest in the political process and a commitment to the principles of the democratic process than simply a belief that he could effect major changes in the delivery of mental health care to Arizona's citizens. He is now 1 voice out of the 91 in the Arizona State House of Representatives, not 1 voice in about 5 million residents of the state. His training as a psychologist, including training in the scientific method, has helped him become a better representative. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
98.
Research has demonstrated that oral reading fluency probes are reliable and valid for indexing reading achievement. If these probes are to be used for decision making, bias must be examined for various factors, including ethnicity, gender, language background, and socioeconomic status. Data from nearly 4,000 Caucasian and Hispanic students in grades one through three were used to examine potential bias in oral reading fluency scores predicting Stanford Achievement Test-Ninth Edition (SAT-9; Harcourt Brace & Co., 1997a, 1997b) Total Reading scores. Using a series of hierarchical multiple regression models, bias was first examined using concurrent SAT-9 scores as the criterion and then examined using subsequent SAT-9 scores as the criterion. The results reveal that it is the combination of factors, not any one in isolation, that significantly contributes to intercept bias findings. Overall, home language emerged as the strongest factor influencing bias in the prediction of SAT-9 scores from oral reading fluency scores. The implications of these findings are discussed as related to current and proposed uses of oral reading fluency probes. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
99.
Stice Eric; Rohde Paul; Seeley John R.; Gau Jeff M. 《Canadian Metallurgical Quarterly》2008,76(4):595
In this depression prevention trial, 341 high-risk adolescents (mean age = 15.6 years, SD = 1.2) with elevated depressive symptoms were randomized to a brief group cognitive-behavioral (CB) intervention, group supportive-expressive intervention, bibliotherapy, or assessment-only control condition. CB participants showed significantly greater reductions in depressive symptoms than did supportive-expressive, bibliotherapy, and assessment-only participants at posttest, though only the difference compared with assessment controls was significant at 6-month follow-up. CB participants showed significantly greater improvements in social adjustment and reductions in substance use at posttest and 6-month follow-up than did participants in all 3 other conditions. Supportive-expressive and bibliotherapy participants showed greater reductions in depressive symptoms than did assessment-only controls at certain follow-up assessments but produced no effects for social adjustment and substance use. CB, supportive-expressive, and bibliotherapy participants showed a significantly lower risk for major depression onset over the 6-month follow-up than did assessment-only controls. The evidence that this brief CB intervention reduced risk for future depression onset and outperformed alternative interventions for certain ecologically important outcomes suggests that this intervention may have clinical utility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.