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991.
Differences in duration judgments made by younger and older adults were reviewed. Previous research is unclear about whether such differences exist and, if so, how they may be explained. The meta-analyses revealed substantial age-related differences. Older adults gave larger verbal estimates and made shorter productions of duration than did younger adults. There were no age-related differences in reproduction of duration or in psychophysical slope relating judged and target duration. Older adults' duration estimates were more variable than were those of younger ones. Findings are discussed in terms of pacemaker rate and attentional resources. An explanation regarding divided attention between nontemporal and temporal information processing best explains the findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
This article presents an elaborated model of organizational regression suggesting that, within the framework of general systems and catastrophe theory, organizational units and whole enterprises can be viewed as struggling to attain a state of super-resilience that enables them to cope effectively with a large number of regressive forces. The model comprises 6 phases of organizational regression that occur either in a 10-stage process or in a chaotically unpredictable but behaviorally understandable and orderly sequence. Internal and external regressive forces that constantly pressure an organization toward less effective performance and more primitive behavior are identified. Organizational barriers and balancing forces that counter the regressive pressures are also described, along with the consequences of regression for individuals and enterprises. Several brief case illustrations (e.g., Montgomery Ward, Apple Computer, and General Electric Corporation) are provided to highlight aspects of this conceptual approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Richard O Sinnott Author vitae 《Computer Standards & Interfaces》1998,19(7):375-385
It could be argued that the primary issue to be dealt with in software engineering today is re-use of software. Current software development rarely, if ever, starts from nothing. Unfortunately, the same cannot be said for the development of specifications. To overcome this problem, various works have attempted to show how specifications can be built using architectural principles. We discuss one such approach in particular, the Architectural Semantics of Open Distributed Processing. We show the limitations of this work with regard to the architecting of specifications and propose a new approach, based on frameworks. To highlight the approach we use the work currently being done in the TOSCA project in its development of a service creation and validation environment for telecommunication services. 相似文献
994.
F Tesson P Richard P Charron B Mathieu C Cruaud L Carrier O Dubourg N Lautié M Desnos A Millaire R Isnard AA Hagege JB Bouhour M Bennaceur B Hainque P Guicheney K Schwartz M Komajda 《Canadian Metallurgical Quarterly》1998,12(6):385-392
The effects of two progestogen-only pills containing either 75 microgram desogestrel (DSG) or 30 microgram levonorgestrel (LNG) on hemostasis were investigated in a double-blind, randomized, controlled study of seven treatment cycles in 78 healthy women. DSG reduced factor VII activity (p < 0.05) and prothrombin fragment 1+2 (p < 0.05) and increased protein S (p < 0.001). LNG reduced factor VII activity (p < 0.01) and plasminogen activity (p < 0.01) and increased tissue-plasminogen activator (t-PA) (p < 0.05). At the end of the post-treatment cycle with DSG, protein S (p < 0.01) and t-PA (p < 0.05) were increased and plasminogen activity was decreased (p < 0.05), whereas with LNG, t-PA was increased (p < 0.001) and prothrombin fragment 1+2 (p < 0.05) and plasminogen activity (p < 0.001) were decreased. Between-group comparisons revealed higher values for DSG regarding the anticoagulatory parameter protein S at cycle 7 (p < 0.01) and post-treatment assessments (p < 0.05), and the fibrinolytic parameter plasmin-antiplasmin complex was higher with DSG at cycle 7 (p < 0.05) and at post-treatment (p < 0.05). Both preparations had comparable and potentially favorable effects of hemostasis, and may offer suitable hormonal contraception to women with a personal or family history of venous thromboembolic diseases. 相似文献
995.
N Fernandez L Monge AL Garcia-Villalon JL Garcia B Gomez G Dieguez 《Canadian Metallurgical Quarterly》1995,294(2-3):483-490
The in vitro effects of endothelin-1 on cerebral veins were studied using cylindrical segments, 5 mm long, from dog pial veins. Isometric responses to endothelin-1 (10(-12)-10(-7) M) and to the endothelin ET(B) receptor agonist, IRL 1620 (Suc-[Glu9,Ala11,15]endothelin-1-(8-21), 10(-12) -10(-7) M), were recorded in veins under control conditions and pretreated with the endothelin ET(A) receptor antagonist, BQ-123 (cyclo-(D-Asp-Pro-D-Val-Leu-D-Trp), 10(-8) -10(-5) M), and the endothelin ETB receptor antagonist, BQ-788 (N-[N-[N-[(2,6-dimethyl-1-piperidinyl)carbonyl]-4-methyl-L-leucyl]-1-(me thoxycarbonyl)-D-tryptophyl]-D-norleucine monosodium, 10(-6) and 10(-5) M). The response to endothelin-1 was also recorded in veins pretreated with the nitric oxide synthesis inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME, 10(-4) M), or the cyclooxygenase inhibitor, meclofenamate (10(-5) M), and in veins without endothelium or placed in medium without Ca2+ but with EDTA (0.1 mM). In control veins, endothelin-1 produced a concentration-dependent contraction (EC50 = 2.0 x 10(-10) M; maximal contraction = 113 +/- 6 mg) and IRL 1620 induced no effects or a small contraction only with high concentrations (10(-8) - 10(-6) M) (EC50 = 1.5 x 10 (-8) M; maximal contraction = 9 +/- 3 mg). BQ-123 shifted the response to endothelin-1 to the right in a parallel, concentration-dependent way, whereas BQ-788, L-NAME or meclofenamate did not modify the response to endothelin-1. Compared with the control, veins in a medium without Ca2+ had similar EC50 values, but a lower maximal contraction induced by endothelin-1 (57 +/- 10 mg, P < 0.05), and veins without endothelium exhibited similar EC50 values. Thus, endothelin-1 produces marked cerebral venoconstriction that could be mainly mediated by activation of endothelin ETA receptors, may be dependent on extracellular Ca2+, and may be independent of endothelium, nitric oxide and prostanoids. 相似文献
996.
997.
Elliott Timothy R.; Shewchuk Richard; Hagglund Kristofer; Rybarczyk Bruce; Harkins Stephen 《Canadian Metallurgical Quarterly》1996,41(4):267
The relation of problem-solving confidence, perceived tolerance of stressors, and situation-specific coping efforts to occupational burnout was examined among 88 nurses in physical rehabilitation units. Participants completed measures of problem solving and burnout, and were administered a questionnaire that required them to list stressors encountered at work and their ability to tolerate this stressor. Participants were also asked to list their typical ways of coping with this stressor. Consistent with predictions, confidence in one's ability to handle problems and perceived tolerance were significantly predictive of lower burnout scores, regardless of time spent on the job. Of the coping variables, emotion-focused coping was significantly associated with higher burnout scores. Post-hoc analyses of self-reported coping activities indicated that some coping efforts (e.g., taking time off from work, confronting a supervisor) could be construed as symptoms of burnout, according to theoretical conceptualizations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Causal explanation and dispositional attribution are distinguished. Causal explanation involves giving an explanation for why a particular event occurred, whereas dispositional attribution involves learning about the characteristics of some entity. Moreover, it is proposed that production of causal explanations requires J. S. Mill's (1872/1973) method of difference, whereas production of dispositional attributions requires Mill's method of agreement. Exp 1 shows that both the method of difference and the method of agreement are used to make causal explanations. Experiments 1, 2, and 3 indicate that lay attributors consistently favor use of the method of agreement but not the method of difference to make dispositional attributions of both faciliatory and inhibitory characteristics. The distinction between causal explanation and dispositional attribution is used to organize seemingly contradictory findings and to provide an integrative framework for models of causal judgment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
The behavior of dissolved Fe, Mn, Cu and Cd in the Duwamish River downstream of a sewage treatment plant located near Seattle, Washington, was investigated in three distinct zones: (1) immediately downstream of the effluent outfall, (2) further downstream in the freshwater portion of the river and (3) in the estuarine mixing zone. A three-end-member tracer model utilizing salinity and dissolved inorganic nitrogen was developed to distinguish physical mixing processes from biogeochemical reactions. The results of this investigation indicate that Fe was removed from the dissolved phase onto particulates near the plant. Although no additional reactions controlled the distribution of dissolved Fe, Mn and Cu in the freshwater portion of the river, Cd was removed from the dissolved phase. In the estuarine mixing zone, a significant fraction of the dissolved Fe and Cu was removed from solution, while Mn and Cd desorbed from particulates. The chemical forms of the trace metals rather than their sources appear to determine their participation in these reactions. 相似文献
1000.
This paper presents a syntax-directed editor dubbed SRE, for syntax recognizing editor. Unlike other syntax-directed editors, SRE enables the user to edit programs with nearly the same natural and unrestrictive ease as a conventional text editor. In addition, it helps identify syntax errors and many typing errors before leaving the editor and attempting to compile a program. Programs are also formatted during entry, thereby providing immediate visual feedback of the recognized structure. The editor replaces the scanner/parser pass of a conventional compiler and thus reduces compilation time substantially. 相似文献