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991.
The collapse of the L'Ambiance Plaza building, under construction in Bridgeport, Conn., in 1987, killed 28 construction workers. A number of concurrent investigations were undertaken to attempt to determine the cause. At least six separate theories were developed. However, a prompt legal settlement kept these investigations from being completed. This paper reviews the collapse and discusses the competing theories. The failure focused controversy on the safety of the lift-slab construction method. Because there is a need in civil engineering education for case studies to illustrate ethical and professional issues as well as technical principles, this paper also addresses these aspects. Ways for civil engineering educators to use this case study to address these issues also are discussed.  相似文献   
992.
The Job Demand-Control model postulates that job control attenuates the effects of job demands on health and well-being. Support for this interactive effect is rather weak. Conceivably, it holds only when there is a match between job control and individual characteristics that relate to exercising control options, such as locus of control, or self-efficacy. This three-way interaction was tested in a sample of 96 service employees, with affective strain and musculoskeletal pain as dependent variables. As hypothesized, job control attenuated the effects of stressors only for people with an internal locus of control. For people with an external locus of control, job control actually predicted poorer well-being and health as stressors increased. For self-efficacy, the corresponding three-way interaction was significant with regard to affective strain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
Recently we have shown that in fibroblasts (NIH 3T3 and Rat-1 cells) inhibition of protein geranylgeranylation leads to a G0/G1 arrest, whereas inhibition of protein farnesylation does not affect cell cycle distribution. Here we demonstrate that in human tumor cells the geranylgeranyltransferase-I (GGTase-I) inhibitor GGTI-298 blocked cells in G0/G1, whereas the farnesyltransferase (FTase) inhibitor FTI-277 showed a differential effect depending on the cell line. FTI-277 accumulated Calu-1 and A-549 lung carcinoma and Colo 357 pancreatic carcinoma cells in G2/M, T-24 bladder carcinoma, and HT-1080 fibrosarcoma cells in G0/G1, but had no effect on cell cycle distribution of pancreatic (Panc-1), breast (SKBr 3 and MDAMB-231), and head and neck (A-253) carcinoma cells. Furthermore, treatment of Calu-1, Panc-1, Colo 357, T-24, A-253, SKBr 3, and MDAMB-231 cells with GGTI-298, but not FTI-277, induced the protein expression levels of the cyclin-dependent kinase inhibitor p21WAF. HT-1080 and A-549 cells had a high basal level of p21WAF, and GGTI-298 did not further increase these levels. Furthermore, GGTI-298 also induces the accumulation of large amounts of p21WAF mRNA in Calu-1 cells, a cell line that lacks the tumor suppressor gene p53. There was little effect of GGTI-298 on the cellular levels of another cyclin- dependent kinase inhibitor p27KIP as well as cyclin E and cyclin D1. These results demonstrate that GGTase-I inhibitors arrest cells in G0/G1 and induce accumulation of p21WAF in a p53-independent manner and that FTase inhibitors can interfere with cell cycle events by a mechanism that involves neither p21WAF nor p27KIP. The results also point to the potential of GGTase-I inhibitors as agents capable of restoring growth arrest in cells lacking functional p53.  相似文献   
994.
Recently, J. J. Starns and J. L. Hicks (2005) have argued that source dimensions are retrieved independently from memory (see record 2005-15992-004). In their innovative experiment, manipulating the retrievability of 1 source feature did not affect memory for a 2nd feature. Following C. S. Dodson and A. P. Shimamura (2000; see record 2000-08540-012), the authors argue that the source memory measure that Starns and Hicks used (known as the average conditional source identification measure) is vulnerable to a response bias in this particular paradigm, and this may undermine Starns and Hicks's conclusion. Starns and Hicks, however, acknowledged this possibility. The authors substantiate this claim by a simulation and by replicating Starns and Hicks's experiment. In 2 further experiments, the authors use an extended multinomial model to analyze data showing that Starns and Hicks's conclusion holds even if results cannot be attributed to response biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
Investigated the independent effects of induced mood on the encoding of persuasive messages and on the assessment of attitude judgments. In Exp 1, positive or negative mood was induced either before the encoding of a counterattitudinal message or before the assessment of attitude judgments. When mood was induced before message presentation, Ss in a bad mood were more persuaded by strong than by weak arguments, whereas Ss in a good mood were equally persuaded by strong and by weak arguments. When Ss encoded the message in a neutral mood, however, the advantage of strong over weak arguments was more pronounced when Ss were in a good rather than in a bad mood at the time of attitude assessment. In Exp 2, Ss exposed to a counterattitudinal message composed of either strong or weak arguments formed either a global evaluation or a detailed representation of the message. Positive, negative, or neutral mood was then induced. Ss in a good mood were most likely and Ss in a negative mood least likely to base their reported attitudes on global evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
Clinical trials on exogenous application of polypeptide growth factors in chronic wounds have not fulfilled the high expectations derived from results of experimental studies. There is no convincing evidence that growth factors may substitute for good wound care and efficient surgical approaches to wound closure. The ultimate goal of treatment of chronic ulcerations remains reconstitution of a durable skin envelope without unstable scarring. Therefore, optimization of current methods of wound therapy, including reconstructive vascular and plastic surgery and adequate metabolic and wound control, should be employed before any adjuvant growth factor therapy is attempted. As long as efficient and inexpensive therapy of chronic wounds by growth factors has not been demonstrated, empincal growth factor treatment should be rejected on scientific and economic grounds. Current use appears to be reasonable only under a regime of controlled clinical studies comparing growth factor treatment with conventional wound therapy and operative measures according to the rules of "good clinical practice".  相似文献   
997.
In-discharge reaction of coal with nitrogen/hydrogen mixtures rather than nitrogen alone raises rates of hydrogen cyanide generation by a factor of 10–50, and makes hydrogen cyanide account for ≈70–90% of the total product-gas volume. From these results and parallel tests with a pure carbon, it is concluded that enhanced formation of hydrogen cyanide is controlled by transient hydrogenation of aromatic carbon and consequent creation of additional (non-aromatic) reaction centres which can be abstracted by N*.  相似文献   
998.
BACKGROUND: Postoperative hypoxaemia may be detected by pulse oximetry monitoring of the arterial haemoglobin saturation (SpO2). The SpO2-values obtained on the preoperative night are presumed to represent baseline values for the patients. The aim of this study was to evaluate the possible difference between nocturnal SpO2-values in the patient's home and in the hospital before operation. METHODS: We included 20 patients, 60 years or older, who underwent continuous monitoring of SpO2 on one night in the patient's home and on the night following hospitalisation before surgery. The alarms were turned off and the values were not accessible to the hospital staff. The SpO2 value was stored every 10 s. We described the general oxygen saturation level using the median of all valid values and we calculated the number of valid SpO2-values at 3 levels: above 90%, between 86 and 90%, and below 86%. RESULTS: The number of valid SpO2-values at home and in the hospital were 2186 and 2330, respectively; the median value was 96% on both occasions. Only 0.36% of the values were below 91% on the two occasions and there were no statistically significant differences between the number of SpO2-values at any of the considered levels. CONCLUSION: Arterial oxygen saturation values measured on the preoperative night in the hospital seem reliable as baseline values for elderly patients.  相似文献   
999.
1000.
Ebene Darstellung eines Vielstoffsystems durch mehrfache Parallelprojektion. Schlackengleichgewichte im System Fe–CaO–FeOn–SiO2–MnOn–MgO bei 1600 °C. Mikroskopische Untersuchung der Schlackenphase. Theoretische Entwicklung von Sättigungslinien für ausgewählte konstante Gehalte von Einzelstoffen. Erörterung der Ergebnisse im Hinblick auf ?LD?- und Siemens-Martin-Schlacken.  相似文献   
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