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201.
The author explored the mathematics efficacy beliefs of 270 South Asian (Indo Canadian) immigrant and Anglo Canadian nonimmigrant Grade 7 students. Self-efficacy beliefs strongly predicted mathematics performance for both cultural groups, but there were differences between the 2 groups in the sources of self-efficacy, the predictiveness of the secondary motivation variables, and the vertical dimensions of individualism and collectivism. It is argued that the Indo Canadian students are more vertical or hierarchical than the Anglo Canadian students and that comparison with others strongly influences their motivation beliefs and the formation of their efficacy beliefs. Self-efficacy in some cultures may be more other-oriented than is typically seen in Western cultures. A caution against generalizing about Asian populations is given, and implications for school settings are explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
202.
Robert G Clyde James L Bown Ted R Hupp Nikolai Zhelev John W Crawford 《Journal of the Royal Society Interface》2006,3(10):617-627
The cell cycle is implicated in diseases that are the leading cause of mortality and morbidity in the developed world. Until recently, the search for drug targets has focused on relatively small parts of the regulatory network under the assumption that key events can be controlled by targeting single pathways. This is valid provided the impact of couplings to the wider scale context of the network can be ignored. The resulting depth of study has revealed many new insights; however, these have been won at the expense of breadth and a proper understanding of the consequences of links between the different parts of the network. Since it is now becoming clear that these early assumptions may not hold and successful treatments are likely to employ drugs that simultaneously target a number of different sites in the regulatory network, it is timely to redress this imbalance. However, the substantial increase in complexity presents new challenges and necessitates parallel theoretical and experimental approaches. We review the current status of theoretical models for the cell cycle in light of these new challenges. Many of the existing approaches are not sufficiently comprehensive to simultaneously incorporate the required extent of couplings. Where more appropriate levels of complexity are incorporated, the models are difficult to link directly to currently available data. Further progress requires a better integration of experiment and theory. New kinds of data are required that are quantitative, have a higher temporal resolution and that allow simultaneous quantitative comparison of the concentration of larger numbers of different proteins. More comprehensive models are required and must accommodate not only substantial uncertainties in the structure and kinetic parameters of the networks, but also high levels of ignorance. The most recent results relating network complexity to robustness of the dynamics provide clues that suggest progress is possible. 相似文献
203.
Les Hatton Andy Wright Stuart Smith Gregg Parkes Paddy Bennett Robert Laws 《Software》1988,18(4):301-329
The portability of software has become a major commercial issue in recent times. Such portability does not come easily, as few if any computer languages are really portable in practice. An additional complicating factor, especially in the commercial environment, is that the resulting software must be efficient. This paper describes the design and successful implementation of a 500,000+ line portable FORTRAN 77 package for the processing of seismic data. The package exhibits demonstrably high efficiency on a wide variety of machines from minicomputers to the largest supercomputers. Experiences gained during this exercise throw much light on the integration of the various thought processes which occur during the software engineering cycle, especially the notion of locality. 相似文献
204.
Summary A series of thermotropic, liquid crystalline (LC) polyesters was prepared in which the mesogenic group contained an unusually
large, polarizable pendant group in an attempt to increase intermolecular interactions so as to impart a more isotropic character
to the mechanical properties of the solid polymer. The series included repeating units containing main chain, polymethylene
flexible spacers of increasing lengths. All of the polymers formed stable nematic LC phases and had relatively low melting
temperatures, but recrystallization from the melt was very slow in each case.
Dedicated to Prof. Dragutin Fleš on the occasion of his 70th birthday 相似文献
205.
The essential elements for a system of customer direct access to electricity supplies are already in place, with protocols for existing pool operation and inter-system coordination, as well as the Western System Power Pool market. Extending our experience with gas and electricity wholesale markets to direct access for large retail electricity customers, then to small customers, is achievable now. 相似文献
206.
Blascovich Jim; Brennan Kelly; Tomaka Joe; Kelsey Robert M.; Hughes Pamela; Coad Mary Lou; Adlin Richard 《Canadian Metallurgical Quarterly》1992,63(1):164
Investigated in 3 experiments the relationships between affect intensity and basal, evoked, and perceived cardiac arousal. Affect intensity was assessed using R. J. Larsen and E. Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (J. Blascovich, 1990). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
207.
Grant Igor; Olshen Richard A.; Atkinson J. Hampton; Heaton Robert K.; Nelson Julie; McCutchan J. Allen; Weinrich James D. 《Canadian Metallurgical Quarterly》1993,7(1):53
The relationship of depressed mood to cognitive disturbance in HIV infection was examined in a sample of 139 homosexual men. Ss were grouped according to the classification of the Centers for Disease Control: 39 were in Group IV, 62 were in Group II or Group III, and 38 were HIV-negative. Ss completed the Profile of Mood States and 10 neuropsychological tests. Analysis employing a classification approach indicated that, although symptoms of depression and neuropsychological impairment were more common in Ss who were HIV-positive, particularly those classified as Group IV, there were no systematic relationships between depression and neuropsychological impairment. Depressed mood and cognitive disturbance each seem to have unique associations to HIV illness status. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
208.
Lutgendorf Susan K.; Russell Daniel; Ullrich Philip; Harris Tamara B.; Wallace Robert 《Canadian Metallurgical Quarterly》2004,23(5):465
This study prospectively examined the relationship between religious attendance, interleukin-6 (IL-6) levels, and mortality rates in a community-based sample of 557 older adults. Attending religious services more than once weekly was a significant predictor of lower subsequent 12-year mortality and elevated IL-6 levels (> 3.19 pg/mL), with a mortality ratio of .32 (95% confidence interval [CI] = 0.15,0.72; p 相似文献
209.
Robert Keller James Karki 《电子产品世界》2003,(12):30-31
第三代移动电话主要依靠宽带码分多址(WCDMA)技术,信号处理技术的发展、体系结构的进步以及新开发的高速数据转换器和运算放大器正在使无线基础结构的设计师们降低成本,更好地实现第三代无线通信系统的目标。 相似文献
210.
Barbara K. Reck Robert B. Gordon 《JOM Journal of the Minerals, Metals and Materials Society》2008,60(7):55-59
Nickel and chromium are essential ingredients in alloys increasingly important for energy-efficient, environmentally friendly
modern technology. Quantitative assessment of the flows of these metals through the world economy from resource extraction
to final disposal informs resource policy, energy planning, environmental science, and waste management. This article summarizes
the worldwide technological cycles of nickel and chromium in 2000. Stainless steel is the major use of these metals, but they
serve numerous other special needs, as in superalloys for high-temperature service, as plating materials, and in coinage.
Because they are used primarily in alloys, novel recycling issues arise as their use becomes more widespread.
“... the great New York and St. Louis double track, nickel plated railroad...”
— Norwalk, Ohio, Chronicle 10 March 1881 announces arrival of surveyors for the future Nickel Plate Railway
“Later [1911] I formed an alloy of Iron and Chromium, which showed remarkable resistance to rust and tarnish ... [It was]
rediscovered by an Englishman named Brearley, in 1914.”
—Elwood Haynes to Stephen F. Roberts, 17 January 1925 相似文献