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51.
Riggio Ronald E.; Riggio Heidi R.; Salinas Charles; Cole Emmet J. 《Canadian Metallurgical Quarterly》2003,7(2):83
Three studies explored the role that basic social/communication skills play in leader emergence and effectiveness. In Study 1, 218 undergraduate students were administered self-report measures of social/communication skills and extraversion, worked in small groups on a problem-solving task, and elected leaders at task midpoint. Coders measured leaders' verbal communication. Groups elected leaders who spoke most and were extraverted but were not more socially skilled. In Study 2, leaders were selected on the basis of their possession of communication skills and led small groups in 2 tasks. More skilled communicators were rated as more effective leaders, but they did not lead more productive groups. Study 3 examined fire service leaders. Social skills were related to satisfaction with the leader but related to leader performance only for higher level leaders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Compared the effects of self-control training, using cognitive-behavioral game play (CB) and biofeedback game play (BF), on the behaviors of 58 male and 5 female 8–12 yr olds with Full Scale IQ of 90 or higher on the Wechsler Intelligence Scale for Children--Revised (WISC--R) and diagnosed with attention deficit hyperactivity disorder (ADHD). The experimental groups were compared to a control game group (GC), which received no self-control training. A 3?×?3 (treatment?×?time) factorial design with repeated measures, using IQ as a covariate, and multiple outcome criteria was employed comparing the groups. Findings support the hypothesis that self-control training by BF reduces a child's perception of his or her self-control problems, but the same does not generalize to parental report of self-control or behavioral measures. Hyperactivity, one of the cardinal symptoms of ADHD, was significantly decreased in GC. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
54.
Children's beliefs about intelligence and school performance. 总被引:1,自引:0,他引:1
The study was designed, first, to explore associations among children's beliefs about intelligence and effort, goal orientations, self-reported learning strategies, and academic achievement. Assessments of all variables were conducted twice over 1 school year on 319 children in Grades 3–6. Results indicate that the belief that intelligence is relatively fixed was associated with the beliefs that performance is relatively stable and that intelligence is global in its effects on performance. This set of beliefs was differentiated from the belief that effort has positive effects on intelligence and performance. Children's beliefs in intelligence as fixed and affecting performance were negatively associated with academic achievement, but a path analysis provided only modest support for the hypothesis that the effect of such beliefs would be mediated by a performance goal orientation and accompanying superficial learning strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Eija Jms Heidi Holkeri Helena Vihinen Mats Wikstrum Marjo Simonen Bjrn Walse Nisse Kalkkinen Juha Paakkola Marja Makarow 《Yeast (Chichester, England)》1995,11(14):1381-1391
Escherichia coli β-lactamase was secreted into the culture medium of Saccharomyces cerevisiae in biologically active form, when fused to the C-terminus of the hsp150δ-carrier. The hsp150δ-carrier is an N-terminal fragment of the yeast hsp150 protein, having a signal peptide and consisting mostly of a 19 amino acid peptide repeated 11 times in tandem. Here we expressed the hsp150δ-carrier fragment alone in S. cerevisiae. Apparently due to a positional effect of the gene insertion, large amounts of the hsp150δ-carrier were synthesized. About half of the de novo synthesized carrier molecules were secreted into the culture medium, the rest remaining mostly in the pre-Golgi compartment. The extensively O-glycosylated carrier fragment was purified from the culture medium under non-denaturing conditions. Circular dichroism spectroscopy showed that it had no regular secondary structure. Nuclear magnetic resonance spectroscopy showed that a non-glycosylated synthetic peptide, the consensus sequence of the repetitive 19 amino acid peptide, also lacked secondary structure. The unstructured carrier polypeptide may facilitate proper folding and secretion of heterologous proteins attached to it. 相似文献
56.
Sex role stereotyping of college professors: Bias in students' ratings of instructors. 总被引:1,自引:0,他引:1
We investigated the impact of three variables on students' ratings of instruction (SRIs): social contact between instructor and students (present vs. absent), the instructor's facial expression (smiling vs. neutral), and the instructor's sex. Subjects were presented with hypothetical scenarios in which these factors varied while behaviors directly related to teaching were held constant. Results revealed an interaction between instructor sex and both of the other two factors: Behaviors indicative of friendliness toward students elevated SRIs for female instructors but not for male instructors. In addition, subjects rated the male professors as more effective than female professors. These findings are consistent with other reports that students expect female instructors to excel in both stereotypically masculine (e.g., competence) and feminine (e.g., warmth) domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Nine Sprague-Dawley rats were trained in a 3-alternative delayed matching-to-sample task in which the samples were rewarded forced choices of 1 arm of a 3-arm starburst maze, and retention was indicated by returning to that arm following a delay or retention interval. If the S made an error on its 1st free choice of a trial, the chosen arm was blocked off, and the S was allowed a 2nd choice between the remaining 2 arms. Ss quickly acquired this task. Exp II showed that choice accuracy was lower with 1-min retention intervals than with immediate tests. In Exp III, there was evidence for 2 separable proactive interference effects. The degree to which prior events influenced responding decreased as the intertrial interval increased. Choice accuracy improved with increasing intertrial interval and declined with increasing retention interval durations. Additionally, choice accuracy was higher when the sample from the previous trial matched the sample from the current trial and lower when they did not match. These results suggest that encoding information about visited spatial locations is a gradual process rather than an all-or-none process in rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
This study addresses the effect of fiber reinforcement, chain extension, and physical foaming agent type on foam morphology and viscosity behavior of pulp fiber reinforced poly(lactic acid) (PLA) biocomposites. PLA reinforced with 0, 10, and 20 wt % of bleached kraft pulp fibers with and without chain extender were foamed using two different physical foaming agents (carbon dioxide and isobutane) by extrusion foaming. Densities, foam morphologies, and viscosities were systematically analyzed and compared from the produced foams. As a conclusion, low-density foams are produced with both foaming agents and fiber levels, fiber addition limiting cell growth. Isobutane provides better dimensional stability with narrower cell size distribution, whereas carbon dioxide enables lower foaming temperature. Chain extension is essential to achieve foam with low density and good cell structure. Contrary to nonchain extended PLA, addition of fibers reduced the viscosity of chain extended PLA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48202. 相似文献
59.
Mari J. Jaakamo Tytti J. Luukkonen Piia K. Kairenius Ali R. Bayat Seppo A. Ahvenjärvi Tuomo M. Tupasela Johanna H. Vilkki Kevin J. Shingfield Heidi M. Leskinen 《Journal of dairy science》2019,102(10):8825-8838
We examined the effects of 2 grass silage-based diets differing in forage:concentrate (FC) ratio and those of a red clover silage-based diet on intake, milk production, ruminal fatty acid (FA) biohydrogenation, milk FA composition, and milk fat globule (MFG) size distribution. Ten multiparous Nordic Red cows received the following treatments: grass silage-based diets containing high (70:30, HG) or low (30:70, LG) FC ratio or a red clover silage-based diet with an FC ratio of 50:50 (RC) on a dry matter basis. Determinations of MFG were performed from fresh milk samples without addition of EDTA so the results of fat globules >1 µm in diameter are emphasized instead of the entire globule population. Lower FC ratio in grass silage-based diets increased milk production with no effect on daily fat yield, leading to 13% lower milk fat concentration. The effect of FC ratio on MFG size was moderate. It did not affect the volume-weighted diameter in grass silage-based diets, although LG lowered the volume-surface diameter of MFG in the size class >1 µm compared with HG. Compared with HG, feeding LG moderately decreased the biohydrogenation of 18:2n-6, leading to a higher level of polyunsaturated fatty acids in milk fat. Feeding RC lowered milk fat concentration and daily milk fat yield compared with grass silage-based diets. The volume-weighted diameter of MFG in the size class >1 µm was smaller in RC milk compared with grass silage-based diets. Feeding RC increased the flow of 18:3n-3 at the omasum by 2.4-fold and decreased the apparent ruminal 18:3n-3 biohydrogenation compared with grass silage-based diets despite similar intake of 18:3n-3. It also resulted in the lowest amount of saturated FA and the highest amounts of cis-9 18:1, 18:3n-3, and polyunsaturated FA in milk. In conclusion, LG decreased milk fat content and induced minor changes in MFG size distribution compared with HG, whereas RC lowered milk fat production, altered milk FA composition to nutritionally more beneficial direction, and led to smaller MFG compared with grass silage-based diets. 相似文献
60.