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91.
Pinto Isabel R.; Marques José M.; Levine John M.; Abrams Dominic 《Canadian Metallurgical Quarterly》2010,99(1):107
In 3 experiments, participants (Ns = 50, 95, and 75, respectively) judged 2 ingroup or outgroup members who occupied 1 of 3 statuses—new members, full members, or marginal members. In each case, 1 of these members adopted a normative position and another supported a deviant position regarding a relevant issue. Participants upgraded normative ingroup full members and derogated deviant ingroup full members compared with all other members. In addition, derogation of deviant ingroup members was associated with a socializing and a punishing intention toward new members and full members, respectively. These results are discussed in terms of the group socialization model (e.g., Levine & Moreland, 1994) and the subjective group dynamics model (e.g., Marques, Paez, & Abrams, 1998). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
A method for analysing systems of isolated single-walled carbon nanotubes is of paramount importance if their structural characteristics are to be fully understood and utilized. Here we offer a simple technique for analysing such systems, with unprecedented contrast, using transmission electron microscope imaging of carbon nanotubes suspended over large holes in a silicon nitride grid. The nanotubes are grown directly on the viewing grids, using the chemical vapour deposition process, thus avoiding the use of chemicals or aggressive treatments. This method is simultaneously non-invasive, reusable, allows the analysis of multiple structures based on carbon nanotubes and is quickly implemented. 相似文献
93.
Duff A.Abrams. 《建筑装饰材料世界》2009,(9):38-41
人们采用了很多不同的方法,发展了若干种理论作为混凝土配合比设计的基础。我只需要提到其中的一小部分来唤醒你的记忆。我们现在的习惯是(我很遗憾地说,几乎所有人都这样做)根据经验来进行混凝土的配合比设计,比如我们使用1:2:4的拌合物,而不考虑原料的特殊类型和搅拌水的用量,也 相似文献
94.
A nanoporous platinum (np-Pt) thin film based hydrogen sensor was fabricated and studied. The np-Pt thin films were fabricated through a method of chemical dealloying and coarsening starting from a CuPt alloy. The alloy thin films of CuxPt1?x were deposited by sputtering copper and platinum at the same time. The dealloying process completely removed the copper from the film. We demonstrate a method to control the porosity of np-Pt by a method of coarsening. Scanning electron microscopy confirmed the presence of porosity with size ranging from a few nanometers to tens of nanometers. A sensor device with four electrodes was fabricated on the np-Pt thin films using a stainless steel mask and by sputtering copper. The electrical characteristics of the sensor exhibit marked sensitivity or current changes in the presence of hydrogen. The results demonstrate that np-Pt thin films configured as a gas sensor have high sensitivity to hydrogen. 相似文献
95.
Herzog Thaddeus A.; Abrams David B.; Emmons Karen M.; Linnan Laura A.; Shadel William G. 《Canadian Metallurgical Quarterly》1999,18(4):369
The transtheoretical model (TTM) posits that processes of change and the pros and cons of smoking predict progressive movement through the stages of change. This study provides both a cross-sectional replication and a prospective test of this hypothesis. As part of a larger study of worksite cancer prevention (the Working Well Trial), employees of 26 manufacturing worksites completed a baseline and 2 annual follow-up surveys. Of the 63% of employees completing baseline surveys, 27.7% were smokers (N?=?1,535), and a cohort of these smokers completed the 2-year follow-up. Cross-sectional results replicated previous studies with virtually all the processes of change and the cons of smoking increasing in linear fashion from precontemplation to preparation (all ps?p? 相似文献
96.
Palmer L Abrams F Carter D Schluter WW 《The Joint Commission journal on quality improvement》1999,25(2):78-94
BACKGROUND: Many physical and psychosocial complications arise from the use of physical restraints. Restraints in nursing homes have been estimated to cause approximately 1 in every 1,000 nursing home deaths. When restraints are removed, quality of life and functional status improve; there does not appear to be an increase in serious falls, and serious injuries may even decline. METHODS: To assess the current status in Colorado nursing homes, in 1997 the Colorado Foundation for Medical Care mailed a questionnaire to 214 nursing homes to identify remaining barriers to restraint reduction. Results were used to plan interventions to further reduce inappropriate use that met most providers' needs. Given providers' need for greater family and public awareness of the risks associated with restraints, the project team developed educational tools for distribution to families and a media campaign for the public. In addition, an assessment tool and educational materials were created to facilitate appropriate use of devices and implementation of least-restrictive interventions. Data were collected before and after the intervention phase on remaining barriers, frequency of assessment, and perceived level of success of restraint reduction. RESULTS: Most of the 175 (82%) of Colorado's 214 long-term care providers who received educational materials found them very useful and recommended expansion to other states. Facilities indicated a higher perceived level of success in reducing restraints, an increase in the frequency of assessments, and a decrease in barriers to restraint reduction. The public awareness campaign, performed in tandem with the state health department, reached more than a half-million people in Colorado, using the slogan, "Restraints Have Risks!" 相似文献
97.
Performance visualization tools of the past decade have yielded new insights into the behavior of sequential, parallel and distributed programs. However, they have three inherent limitations: (1) they only display what happened in one execution of a program (this is dangerous when analyzing concurrent applications, which are prone to non-deterministic behavior); (2) a human uses one or more bandwidth-limited senses with a visualization tool (this limits the scalability of a visualization tool); (3) the relationship of ‘interesting’ program events is often separated in time by other events; thus discerning time-dependent behavior often hinges on finding the ‘right’ visualization—a possibly time-consuming activity. CHITRA93 complements visualization systems, while alleviating these limitations, and analyzes a set (or ensemble) of traces by combining the visualization of a few traces with a statistical analysis of the entire ensemble (overcoming (1)). It reduces the ensemble to empirical models that capture the time-dependent relationships of ‘interesting’ program events through application, programming language and computer architecture independent analysis techniques (addressing (2) and (3)). It also incorporates the following transforms, such as aggregation, that simplify the ensemble and reduce the state-space size of the models generated; a user interface that allows certain transforms to be selected by editing the visualization with a mouse; homogeneity tests that allow partitioning of an ensemble; an efficient semi-Markov model generation algorithm whose computation time is linear in the sum of the lengths of the traces comprising the ensemble; and a CHAID-based model that can fathom non-Markovian relationships among transitions in the traces. The use of CHITRA93 is demonstrated by partitioning ten parallel database traces with nearly 8,000 states into two homogeneous subsets, each modeled by an irreducible, periodic and hierarchical stochastic process with as few as four states. 相似文献
98.
J. R. Aldrich W. R. Lusby J. P. Kochansky C. B. Abrams 《Journal of chemical ecology》1984,10(4):561-568
In the predatory spined soldier bug,Podisus maculiventris, the dorsal abdominal glands are much smaller in adult females than males. Females produce a mixture of (E)-2-hexenal, (E)-2-octenal, (E)-2-hexenoic acid, benzaldehyde, and nonanal in these glands. The female dorsal abdominal gland secretion may be a close-range pheromone since the dorsal abdominal gland secretion from males has been shown to be a long-range aggregation pheromone in this species. The metathoracic scent gland secretions of male and female spined soldier bugs are apparently identical, and similar to that of other pentatomids, except for the presence of the monoterpene alcohol, linalool.Mention of a commercial product does not constitute an endorsement of this product by the USDA. 相似文献
99.
R Niaura B Marcus A Albrecht P Thompson D Abrams 《Canadian Metallurgical Quarterly》1998,30(9):1414-1418
PURPOSE: This study investigated the combined effects of exercise and smoking cessation on serum lipids. METHODS: Eighteen female smokers quit smoking using standard behavioral methods combined with exercise (N = 9) or with a nonexercise contact time control (N = 9). The smoking cessation program for both groups consisted of 12 weekly 1-h behavioral modification sessions held over 12 wk. Exercise training consisted of three supervised 45-min sessions per week for 12 wk. Contact control consisted of three health education lectures/discussions per week for 12 wk. Fitness (estimated VO2 peak), dietary variables, and fasting serum lipids and lipoproteins were assessed before and at the end of treatment. VO2 peak increased in the exercise subjects compared with the controls. RESULTS: Total caloric intake as well as total fat and carbohydrate increased significantly after smoking cessation in the controls, but there were no dietary changes in the exercise group. high density lipoprotein (HDL)-C2 increased (7.6 mg x dL(-1), P < 0.01) in the exercise group, whereas the increases in HDL and its subfractions did not attain statistical significance in the contact control group. Total cholesterol, low density lipoprotein (LDL)-C, and triglycerides did not change in either group. CONCLUSIONS: We conclude that exercise training magnifies the increase in HDL-C that usually occurs with smoking cessation. 相似文献
100.
Four experiments addressed the influence of variables on lexical decision performance after response initiation has occurred. In Experiment 1, participants made an arm movement in one direction for word trials and pressed a button with the other hand for nonword trials. The results indicated that word frequency not only modulated the speed to initiate the arm movement, but also modulated the acceleration and force of the movement after initiation. The results of Experiment 2 indicated that word frequency and stimulus degradation produced large and additive effects on response latency, accuracy, and the force of the response after initiation. In Experiments 3 and 4, participants made the same arbitrary speech response in a modified lexical decision task for both high- and low-frequency words. The results indicated that both the onset and duration of the speech response were modulated by word frequency. The results are viewed as most consistent with an enabled response model, wherein early operations can enable appropriate action systems before central decisions are made. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献