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51.
Ford Kentya H.; Diamond Pamela M.; Kelder Steven H.; Sterling Kymberle Landrum; McAlister Alfred L. 《Canadian Metallurgical Quarterly》2009,23(2):271
Attitudes toward smoking, self-efficacy to avoid smoking, and smoking intention, widely cited correlates of youth smoking prevention, are often measured in large-scale youth tobacco surveys. The psychometric properties of these scales have not been well studied among middle school youth. We examined the factorial, discriminate, and convergent validity of these scales among sixth to eighth graders from a convenience sample of 22 Texas middle schools (51.2% female; 51.21% White, 32.1% Hispanic, 16.9% African American, and 8.8% Other; 67.8% nonsmokers, 21.9% experimental smokers; 3.3% former smokers; and 7.6% current smokers). Confirmatory factor analysis and invariance testing suggest that smoking attitudes, self-efficacy, and intention have evidence of construct validity in this multiethnic sample, and the scales are appropriate to assess these constructs among middle school adolescents. Additional studies are needed to establish additional evidence of validity of these constructs in other middle school samples and other subgroups (e.g. current, experimental, and former smokers). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Michael Mahoney, who made seminal contributions not only to the Society for the Exploration of Psychotherapy Integration (SEPI) but also to the entire field of psychotherapy, died a tragic death at the age of 60 on May 31, 2006. He published more than 250 scholarly articles and chapters, authored and edited 19 books (one of which was awarded a Citation Classic by the Science Citation Index), edited 4 journals, and served on 23 editorial boards plus numerous guest editorships and advisory boards. His research spanned a tremendous breadth without sacrificing depth. Primarily, however, he inquired into development across the life course, including but not limited to psychotherapy. Initially trained as a behaviorist, he played a significant role in the cognitive revolution in psychology; he was also a leading figure in constructivist psychotherapies. He was a Fellow of the World Academy of Art and Science, as well as a Fellow of the American Association for the Advancement of Science. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
We develop a new method for estimating the discrepancy of tensors associated with multiparty communication problems in the “Number on the Forehead” model of Chandra, Furst, and Lipton. We define an analog of the Hadamard property of matrices for tensors in multiple dimensions and show that any k-party communication problem represented by a Hadamard tensor must have Ω(n/2 k ) multiparty communication complexity. We also exhibit constructions of Hadamard tensors. This allows us to obtain Ω(n/2 k ) lower bounds on multiparty communication complexity for a new class of explicitly defined Boolean functions. 相似文献
54.
J. Benziger L. Cadonati F. Calaprice M. Chen A. Corsi F. Dalnoki-Veress R. Fernholz R. Ford C. Galbiati A. Goretti E. Harding Aldo Ianni Andrea Ianni S. Kidner M. Leung F. Loeser K. McCarty D. McKinsey A. Nelson A. Pocar C. Salvo D. Schimizzi T. Shutt A. Sonnenschein 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2009,608(3):464-474
The system for controlled filling of the nested flexible scintillator containment vessels in the Borexino solar neutrino detector is described. The design and operation principles of pressure and shape monitoring systems are presented for gas filling, gas displacement by water, and water displacement by scintillator. System specifications for safety against overstressing the flexible nylon vessels are defined as well as leak-tightness and cleanliness requirements. The fluid-filling system was a major engineering challenge for the Borexino detector. 相似文献
55.
A risk-based strategy for Listeria monocytogenes has been developed by New Zealand Food Safety Authority. Incidents of L. monocytogenes in ready-to-eat foods reported to the regulatory authority were analysed to identify common factors that contributed to the contamination. In addition, the current regulatory framework and available food industry guidance were reviewed to prepare a strategy that will provide a consistent and informed approach to managing the risk of L. monocytogenes. Also recognised is the future impact of an aging population and an increase in the availability and range of chilled ready-to-eat foods that should be integrated into the strategy if an objective of ‘no increase in the reported incidence of foodborne listeriosis after five years’ is to be achieved. 相似文献
56.
G. F. Aouad J. A. Kirkhami P. S. Brandon F. E. Brown G. S. Cooper S. Ford 《Construction Management & Economics》2013,31(5):384-397
Modelling of knowledge in the construction industry is a cumbersome task because of the large amount of data involved and the lack of automated information-modelling tools. Adoption of a method and an automated CASE (Computer-Aided Software Engineering) tool could eliminate many problems encountered in the development of information systems in the construction industry. In particular, this approach may help to assess the information requirements and define strategies for such information systems. The Information Engineering Method (IEM) is introduced to illustrate hoar the conceptual models may be improved by using this method. Additionally Texas Instruments' Information Engineering Facility (IEF?) CASE tool is described to illustrate the advantages of automating such a method. The introduction of conceptual modelling in the construction industry using data and process models should lead to a better structuring of information. This should result in the development of well defined and structured, not ad hoc, applications. This conceptual modelling approach using information engineering is currently being used at the University of Salford to study the potential development of an integrated database (design, procurement and management of construction) for the construction industry. The case study describes the information analysis phase of the procurement process included towards the end of this paper. 相似文献
57.
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59.
据iSuppli公司,由于全经济和电子市场继续复苏,尽管2011年半导体产业不会再现今年预期中的强劲表现,但将继续增长.
2011年全球半导体销售额将达到3174亿美元,比今年预期的3020亿美元温和增长5.1%. 相似文献
60.
Arsenic mobility in natural environments is controlled primarily by sorption onto metal oxide surfaces, and the extent of this sorption may be influenced strongly by the presence of other dissolved substances that interact with surfaces or with arsenic itself. Natural organic matter (NOM), a prevalent constituent of natural waters, is highly reactive toward both metals and surfaces and is thus a clear candidate to influence arsenic mobility. The objectives of this study were therefore to reveal the influences of diverse NOM samples on the sorption of arsenic onto hematite, a model metal oxide, as well as to reveal influences of arsenic on the sorption of NOM, using conditions and concentrations relevant to natural freshwater environments. Of the six NOM samples tested, four formed aqueous complexes with arsenate and arsenite. The extent of complexation varied with the NOM origin and, in particular, increased with the cationic metal (primarily Fe) content of the NOM sample. In addition, every NOM sample showed active redox behavior toward arsenic species, indicating that NOM may greatly influence redox as well as complexation speciation of arsenic in freshwater environments. When NOM and As were incubated together with hematite, NOM dramatically delayed the attainment of sorption equilibrium and diminished the extent of sorption of both arsenate and arsenite. Consistent with this result, when NOM and As were introduced sequentially, all NOM samples displaced sorbed arsenate and arsenite from hematite surfaces, and arsenic species similarly displaced sorbed NOM from hematite in significant quantities. Competition between NOM and As for sorption thus appears to be a potentially important process in natural waters, suggesting that NOM may play a greater role in arsenic mobility than previously recognized. In addition, in all sorption experiments, arsenite was consistently desorbed or prevented from sorbing to a greater extent than arsenate, indicating that interactions with NOM may also partially explain the generally greater mobility of arsenite in natural environments. 相似文献