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101.
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Wallace J. Craig; Edwards Bryan D.; Arnold Todd; Frazier M. Lance; Finch David M. 《Canadian Metallurgical Quarterly》2009,94(1):254
As a test of the 2-dimensional model of work stressors, the present study proposed differential relationships between challenge stressors and hindrance stressors and role-based performance, which were expected to be moderated by organizational support. In a sample of 215 employees across 61 offices of a state agency, the authors obtained a positive relationship between challenge stressors and role-based performance and a negative relationship between hindrance stressors and role-based performance. In addition, organizational support moderated the relationship between challenge stressors and role-based performance but did not moderate the relationship between hindrance stressors and role-based performance. This suggests that organizations would benefit from increasing challenges in the workplace as long as they are supportive of employees and removing hindrances. Further implications for organizational theory and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Inherently conducting polymers (ICPs) have been an area of intense interest over the past 30 years, culminating with the award of the 2000 Nobel Prize in Chemistry to MacDiarmid, Heeger and Shirakawa. More recently the unique properties of these materials (e.g., higher conductivity, more rapid discrete electrochemical switching processes) apparent at the nanodimension have become accessible. Significant breakthroughs in synthesis and fabrication of inherently conducting polymers with nanodimensional control have made this possible. This review aims to discuss some of the synthetic approaches researchers have made in an attempt to probe the nano domain as well as some of the property enhancements afforded to these structures. 相似文献
104.
Vickery Chad D.; Gontkovsky Samuel T.; Wallace Jeanette J.; Caroselli Jerome S. 《Canadian Metallurgical Quarterly》2006,51(1):30
Objective: The current study explored the effectiveness of a group therapy intervention that was focused specifically on self-concept changes following acquired brain injury (ABI). Method: Eighteen individuals in the postacute phase of recovery underwent a 6-week group therapy intervention and were administered a self-concept measure before and after the intervention. Results: Group members showed a significant increase (improvement) in self-concept ratings at the end of the group intervention. Conclusions: Although the results of this study suggest that this intervention may be helpful in improving self-concept following ABI, further exploration is clearly warranted. Future research is needed to investigate the impact of self-concept on emotional adjustment, participation in rehabilitation activities, and functional outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Wallace DJ Van Gilder T Shallow S Fiorentino T Segler SD Smith KE Shiferaw B Etzel R Garthright WE Angulo FJ 《Journal of food protection》2000,63(6):807-809
In 1997, the Foodborne Diseases Active Surveillance Program (FoodNet) conducted active surveillance for culture-confirmed cases of Campylobacter, Escherichia coli O157, Listeria, Salmonella, Shigella, Vibrio, Yersinia, Cyclospora, and Cryptosporidium in five Emerging Infections Program sites. FoodNet is a collaborative effort of the Centers for Disease Control and Prevention's National Center for Infectious Diseases, the United States Department of Agriculture's Food Safety and Inspection Service, the Food and Drug Administration's Center for Food Safety and Applied Nutrition, and state health departments in California, Connecticut, Georgia, Minnesota, and Oregon. The population under active surveillance for foodborne infections was approximately 16.1 million persons or roughly 6% of the United States Population. Through weekly or monthly contact with all clinical laboratories in these sites, 8,576 total isolations were recorded: 2,205 cases of salmonellosis, 1,273 cases of shigellosis, 468 cases of cryptosporidiosis, 340 of E. coli O157:H7 infections, 139 of yersiniosis, 77 of listeriosis, 51 of Vibrio infections, and 49 of cyclosporiasis. Results from 1997 demonstrate that while there are regional and seasonal differences in reported incidence rates of certain bacterial and parasitic diseases, and that some pathogens showed a change in incidence from 1996, the overall incidence of illness caused by pathogens under surveillance was stable. More data over more years are needed to assess if observed variations in incidence reflect yearly fluctuations or true changes in the burden of foodborne illness. 相似文献
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Nulling interferometry, a proposed technique for dimming a star relative to its surroundings by destructively interfering the light collected by two individual telescopes [Bracewell, Nature 274, 780-781 (1978); Shao and Colavita, Ann. Rev. Astron. Astrophys. 30, 457-498 (1992)], has the potential to permit the direct detection of nearby extrasolar planets. However, because of the extremely high degree of symmetry required for useful levels of starlight nulling, the technique remains in its infancy. We present results of laboratory experiments with a rotational shearing interferometer that are aimed at demonstrating the feasibility of deep nulling at the levels needed for direct planet detection. Our first results include the successful nulling of red laser light to a part in 10(5) and the stabilization of the null leakage to a part in 10(4). 相似文献
109.
The expression of luteinizing hormone-releasing hormone (LHRH) and its receptors has been demonstrated in a number of human malignant tumors, including cancers of the breast, ovary, endometrium and prostate. These findings suggest the presence of an autocrine regulatory system based on LHRH. Recent studies in our laboratory have demonstrated that the function of LHRH produced by ovarian cancer cells is the inhibition of their proliferation. Dose-dependent antiproliferative effects of LHRH-agonists have been observed by several laboratories in cell lines derived from the above cancers. Interestingly, also LHRH-antagonists have marked antiproliferative activity in most of the ovarian, breast and endometrial cancer cell lines tested so far, indicating that the dichotomy of LHRH-agonists/LHRH-antagonists is not valid for the LHRH-system in cancer cells. In addition, our data suggest that the classical LHRH receptor signal transduction mechanisms known from the pituitary (phospholipase-C, protein kinase C, adenylyl cyclase) are not involved in the mediation of LHRH effects in cancer cells. Data obtained by several groups, including ours, rather suggest that LHRH analogs interfere with the signal transduction of growth-factor receptors and related oncogene products associated with tyrosine-kinase activity. The mechanism of action is probably an LHRH-induced activation of a phosphotyrosine phosphatase, counteracting the effects of receptor associated tyrosine kinase. In our hands, LHRH analogs virtually blocked the EGF-induced MAP-kinase activity of ovarian and endometrial cancer cells. The pharmacological exploitation of this mechanism might provide promising new therapies for these cancers. 相似文献
110.