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21.
This article is the continuation of M. Schommer's (1993) study, in which the development of secondary students' beliefs about the nature of knowledge and learning, or epistemological beliefs, was examined. High school students (N?=?69) completed an epistemological questionnaire as freshmen in 1992 and as seniors in 1995. Repeated-measures analyses revealed that their beliefs in fixed ability to learn, simple knowledge, quick learning, and certain knowledge changed as they neared the end of their 4th year in high school. In addition, the less students believed in quick learning, the better grade point average they earned. These results are consistent with a cross-sectional study (M. Schommer, 1993) establishing substantial differences in students' epistemological beliefs across the high school years and thus strengthen the case that there is development of epistemological beliefs related to learning during high school. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
This study provides estimates of comorbid psychiatric disorders in women with binge eating disorder (BED). Sixty-one BED and 60 control participants, who were recruited from the community, completed the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-III-Revised (DSM-III-R) Axis I and Axis II disorders and self-report measures of eating and general psychiatric symptomatology. Regarding psychiatric diagnoses, women with BED had higher lifetime prevalence rates for major depression. any Axis I disorder, and any Axis II disorder relative to controls. BED women also evidenced greater eating and psychiatric symptomatology than did controls. Results suggest that the prevalence of comorbid psychiatric disorders in BED may be lower than previously indicated by clinical studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
Believing they were exchanging attitude surveys with a stranger, 270 undergraduates of high or low self-esteem (Texas Social Behavior Inventory) were randomly assigned to 0, 50, or 100% attitude similarity conditions. They indicated on the Interpersonal Judgment Scale their attraction to the stranger and estimates of the stranger's probable attraction to them. Attitude similarity significantly affected Ss' attraction to the stranger and estimates of strangers' attraction to the S. Ss closely approximated predictions of D. Byrne and D. Nelson's (1965) formula in estimating attraction from the stranger. Moreover, attitude similarity influenced goodness of fit between formula predictions and attraction estimates and influenced assumptions about attraction reciprocity. Self-esteem did not influence attraction to the stranger or expected attraction from the stranger. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
California Tobacco Survey respondents were asked the intensity of their cigarette smoking 1 year previously and at the time of the survey. Respondents reported a generally lower smoking intensity at survey time compared with 1 year previously. Multivariable statistical models on the change in smoking intensity in the past year were fitted to assess the effects of low-tar cigarette use, a quit attempt in the past year, smoking intensity 1 year previously, and demographic variables (age, education, income, and race). The most important predictor of change in intensity was the intensity 1 year previously. The next most important predictor was whether a quit attempt had been made in the previous year. The demographic variables also were found to have a significant effect, although their effects were of smaller magnitude. Low-tar cigarette use was not a significant predictor of change in intensity in multivariable analysis. The effect of a quit attempt on the reduction in intensity of smoking suggests that periods of cessation may reduce the intensity of smoking and the level of addiction for several months following relapse. Consequently, it may be important to control for cessation activity in studies comparing exposures from conventional tobacco products to exposures from new products that purport to offer lower harm.  相似文献   
25.
Experiments were carried out in control and Ehrlich ascites carcinomatous mice to determine whether orbital venous sinus blood could be used to reflect blood in the systemic circulation (decapitation blood) in the case of a rapidly turning over metabolic fuel such as free fatty acids. The early time course of intravenously injected, labeled free fatty acids was measured using [9,10-3H]palmitic acid and [1-14C]linoleate complexed to mouse serum. No significant differences between decapitation and orbital sinus blood were found at early times in either group of mice. The orbital sinus clearly contains blood that is not stagnant and is replaced so rapidly that it is suitable for studying very rapidly turning over, circulating metabolites. Supported in part by VA Medical Research and NIH, USPHS Grant No. CA 15813.  相似文献   
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"A complex task setting provided by the simulation of a radar air traffic control system was the context employed to evaluate the extent to which work-team productivity is modifiable as a consequence of different supervisors and supervisory procedures under different task loads. Six two-man teams were observed. Each team worked under each of three supervisors. The supervisors shifted from team to team. Three techniques were adopted alternately: laissez-faire, active monitoring, and direct participation. It was observed that the individual supervisor was a more consistent influence on performance than the particular role he employed. The effect of role per se was significant but interpretable only in light of the particular performance criterion used. For example, processing speed was greatest under laissezfaire conditions, while error avoidance was superior under the conditions which required more overt supervisory activity. Task load was not found to be an interactive factor." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
Macrocyclic trichothecenes, mycotoxins produced by Stachybotrys chartarum, have been implicated in adverse reactions in individuals exposed to mold-contaminated environments. Cellular and humoral immune responses and the presence of trichothecenes were evaluated in patients with mold-related health complaints. Patients underwent history, physical examination, skin prick/puncture tests with mold extracts, immunological evaluations and their sera were analyzed for trichothecenes. T-cell proliferation, macrocyclic trichothecenes, and mold specific IgG and IgA levels were not significantly different than controls; however 70% of the patients had positive skin tests to molds. Thus, IgE mediated or other non-immune mechanisms could be the cause of their symptoms.  相似文献   
29.
Thin-film GaAs waveguides were designed and fabricated by molecular beam epitaxy for use in mid-infrared (MIR) evanescent field liquid sensing. Waveguides were designed to facilitate the propagation of a single mode at a wavelength of 10.3 microm emitted from a distributed feedback quantum cascade laser, which overlaps with molecular selective absorption features of acetic anhydride. The characterization of the waveguides shows transmission across a broad MIR band. Evanescent field absorption measurements indicate a significant sensitivity enhancement in contrast to multimode planar silver halide waveguides.  相似文献   
30.
Despite the rapid growth in nanotechnology, very little is known about the unintended health or environmental effects of manufactured nanomaterials. The development of nanotechnology risk assessments and regulations requires quantitative information on the potential for exposure to nanomaterials. The objective of this research isto characterize airborne particle concentrations during the production of carbonaceous nanomaterials, such as fullerenes and carbon nanotubes, in a commercial nanotechnology facility. We measured fine particle mass concentrations (PM2.5), submicrometer size distributions, and photoionization potential, an indicator of the particles' carbonaceous content, at three locations inside the facility: inside the fume hood where nanomaterials were produced, just outside the fume hood, and in the background. The measurements were not selective for engineered nanomaterials and may have included both engineered nanomaterials and naturally occurring or incidental particles. Average PM2.5 and particle number concentrations were not significantly different inside the facility versus outdoors. However, large, short-term increases in PM2.5 and particle number concentrations were associated with physical handling of nanomaterials and other production activities. In many cases, an increase in the number of sub-100 nm particles accounted for the majority of the increase in total number concentrations. Photoionization results indicate that the particles suspended during nanomaterial handling inside the fume hood were carbonaceous and therefore likely to include engineered nanoparticles, whereas those suspended by other production activities taking place outside the fume hood were not. Based on the measurements in this study, the engineering controls at the facility appear to be effective at limiting exposure to nanomaterials.  相似文献   
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