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11.
Although innovation is highly valued in organizations, early-career professionals face a paradox of bringing in novel ideas, yet having varied latitude and support to see these new ideas through. Building on 35 critical-incident-based interviews with early-career engineers in the United States, this study illuminates the socially situated dynamics of their innovation efforts, examining the process of such promotive proactive behaviour. We find that all participants reported some engagement in creating, championing and implementing new ideas, typically in the form of self-initiated improvements to the tools and processes participants used in their jobs. Encouragement from direct supervisors, supportive organizational cultures and practices, job scope, time afforded and one's perceived status were key considerations in determining whether to take such initiative. Carrying out innovative work behaviours, in turn, was largely dependent on continued employee initiative and ad hoc, informal cooperation, with individual effort punctuated by influential interactions with others that often determined the perceived valence of efforts. The study adds to understanding the social interactions and perceptions of voice required for innovative work behaviour, revealing when and to whom these prerequisites are afforded. Implications for organizations' innovation capacity and new hires' participation in innovation are discussed.  相似文献   
12.
This paper looks at stress intensity factors of cracks in resistance spot welded joints. Stress intensity factors have been used in the past to predict fatigue crack propagation life of resistance spot welds. However, the stress intensity factors from all previous work was based on assumed initial notch cracks at the nugget, parallel to the sheets. Physical evidence shows, however, that fatigue cracks in spot welds propagate through the thickness of the sheets rather than through the nugget. In this work, stress intensity factors of assumed notch cracks and through thickness cracks in tensile shear (TS) and modified coach peel (MCP) specimens were determined by the finite element method. The finite element results from the assumed notch cracks were compared with the results in the literature and were found to be in agreement with the results from Zhang’s equations [Int. J. Fract. 88 (1997) 167]. The stress intensity factors of assumed notch cracks were found to be different from those of through thickness cracks. To date, no analytic equations for stress intensity factors of through thickness cracks in spot welds have been published. In the current work, simple equations are proposed to estimate the KI and KII values of through thickness cracks in TS and MCP specimens.  相似文献   
13.
[Correction Notice: An erratum for this article was reported in Vol 117(3) of Journal of Abnormal Psychology (see record 2008-11014-022). In the aforementioned article, Amy K. Cuellar's last name was misspelled. The corrected list of author names is: Sheri L. Johnson, Amy K. Cuellar, Camilo Ruggero, Carol Winett-Perlman, Paul Goodnick, Richard White, and Ivan Miller.] To date, few prospective studies of life events and bipolar disorder are available, and even fewer have separately examined the role of life events in depression and mania. The goal of this study was to prospectively examine the role of negative and goal-attainment life events as predictors of the course of bipolar disorder. One hundred twenty-five individuals with bipolar I disorder were interviewed monthly for an average of 27 months. Negative and goal-attainment life events were assessed with the Life Events and Difficulties Schedule. Changes in symptoms were evaluated using the Modified Hamilton Rating Scale for Depression and the Bech-Rafaelsen Mania Scale. The clearest results were obtained for goal-attainment life events, which predicted increases in manic symptoms over time. Negative life events predicted increases in depressive symptoms within regression models but were not predictive within multilevel modeling of changes in depressive symptoms. Given different patterns for goal attainment and negative life events, it appears important to consider specific forms of life events in models of bipolar disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
The extent to which protein synthesis is involved in working memory was investigated with the protein synthesis inhibitor anisomycin (ANI). Male albino and Long-Evans rats were trained to perform accurately on a 12-arm radial maze when delays of 240 min were interposed between Choice 6 and Choice 7. Bilateral hippocampal cannulas were then implanted. Accuracy on Choices 7–22 was studied when ANI (80 μg/μl) or saline was injected either 30 min before Choice 1 or 5–20 min after Choice 6 in Exp I. Pretrial injection of ANI significantly impaired performance following the 240-min delay, whereas ANI injected during the delay had no such effect. In Exps II and III, the ANI-induced amnesia was replicated, and the temporal course of development of the amnesia was determined. Pretrial administration of ANI did not significantly affect retention after a 2-min delay but produced amnesia after delays of 15 min or longer. Data suggest that protein synthesis is important for the formation of temporary memories, provided the retention interval is long enough. It is suggested that working memory includes both short- and long-term components. Protein synthesis appears to be important for formation of the long-term component, but not the short-term component, of working memory. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
Field-caught adult male and femaleAedes hendersoni are difficult to distinguish from the sibling speciesA. triseriatus. We found that mosquitoes from the same sex of the sibling species can not be readily separated either by unique cuticular hydrocarbon components or by differences in percent composition of those components. Multivariate analysis of the cuticular hydrocarbon data does not provide good separation. Cuticular hydrocarbons were identified using gas chromatography electron-impact mass spectrometry and gas chromatography chemical-ionization mass spectrometry. Flame-ionization capillary gas chromatography was used for quantitative analysis of individual mosquitoes. Sixty-four hydrocarbons with chain lengths from C16 to greater than C46 were common to both species. Identified hydrocarbon components weren-alkanes, monomethylalkanes, dimethylalkanes, trimethylalkanes, and alkenes.Diptera: Culicidae.  相似文献   
16.
This article addresses two methodological questions that are crucial for research on the natural language in the counseling process: (a) What fraction, or segment, of an interview best represents the entire interview? (b) Do different starting points yield different results? Using a variety of data sets and process measures, we tested segment generalizability in different formats of counseling (individual and family) and with different coding systems (of client and counselor behavior). Results from three studies suggested that, whereas starting points made little difference, generalizing from any size segment to a whole session should not be done when interviews are examined individually. On the other hand, when interviews are aggregated, even fairly small segments can be sampled reliably. In making their own sampling decisions, investigators should consider theoretical and clinical significance and conduct subsample generalizability tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
Compared the cognitions of 294 low, moderate, and high test-anxious (the Test Anxiety Scale for Children) 5th and 6th graders in an analog test situation. High test-anxious Ss reported significantly more task-debilitating cognitions than either moderate- or low-anxious Ss, including negative evaluations and off-task thoughts. High test-anxious Ss also reported fewer positive evaluations than low test-anxious Ss, whereas moderately anxious Ss did not differ significantly from either extreme group. It was unexpected that the moderate- and high-anxious groups reported significantly more on-task thoughts than the low-anxious group and did not significantly differ from each other. Both test anxiety and cognitions showed significant although modest relations with actual task performance after the effects of ability were partialled out. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
18.
19.
Examined somatic androgyny and IQ in 3 longitudinal studies, conducted at the Institute of Human Development, in order to determine how robust the androgyny–ability relationships reported in recent studies are, and whether these relationships are found after sexual maturity is attained. Results do not reveal significant relationships between androgyny and abilities at either adolescence or middle adulthood, although trends are in the predicted directions. There were no systematic findings from analyses separating aspects of somatic androgyny that are more likely to be primarily under control of the sex hormones as opposed to those that are probably subject to other genetic and/or environmental influences. These results are discussed in terms of factors that might moderate androgyny–ability relationships. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
20.
Larval weight of Tribolium castaneum was used to evaluate six varieties of common beans (Phaseolus vulgaris). Beans incorporated into test diets were raw, autoclaved, or extracted with either water or 80% methanol. All treatments improved the nutritional quality of beans when compared to raw beans. The bean extracts were growth depressing. In another study heating of the freeze-dried water extract of black beans improved its nutritive value but not of the methanol extract. Tribolium castaneum larvae may be used to evaluate the nutritional quality of Phaseolus vulgaris and different bean treatments.  相似文献   
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