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91.
Using a national sample of hospital discharges, we found identical seasonal patterns for spontaneous abortions and conceptions but no significant seasonal variation in the rate of spontaneous abortions per 1,000 conceptions. The differences between our findings and those of previous investigators of spontaneous abortion may reflect our more comprehensive definition of spontaneous abortion, our more complete estimate of the monthly number of conceptions, and our more rigorous statistical analysis. The periodic regression analysis (PRA) reported in our study may be useful in other studies that monitor short-term trends. 相似文献
92.
The Cartter Report and Roose-Andersen Reports (sponsored by the American Council of Education) on quality of graduate education in American universities have been used as a basis for national policy and funding judgments, and for institutional, academic discipline, and student applicant uses. It is argued that instead of serving the public purposes for which they were intended, these reports serve more directly private guild interests of the participating disciplines, particularly psychology. Reasons include the fact that psychology has become increasingly technician-oriented, and the sampling procedure used to select raters and the questions asked were biased. These issues could be better approached by defining appropriate models of excellent graduate programs, developing scales for rating the variables considered to contribute to excellence, and then assessing the validity of those measures. The consequences of present biased rating procedures are far too significant for society and students for psychologists to continue to ignore. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
A workable psychology of individuality is "one that would generate good research ideas, which, in turn, would lead to steady increases in dependable knowledge." Individual uniqueness "is described primarily in terms of choice and organization, and I consider it the task of psychologists to make those concepts workable—to bring them into the general stream of thinking in research, assessment, and practical activities." Tyler stresses "the significance of concepts of choice and organization in an inclusive psychology of the development of the human individual… . At each stage of our lives, we impose limits on the next stage, by the choices we make and the ways in which we organize what we have experienced." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
95.
M. G. O'Reilly P. O. Olomolaiye A. H. Tyler T. Orr 《Building Research & Information》1994,22(5):247-251
A useful review of issues of health and safety linked to legislation, as well as highlighting the most serious types of accidents identified in the survey. 相似文献
96.
Form factors are used in radiosity image synthesis to describe the fraction of diffusely reflected light leaving one surface and reaching another. They incorporate fundamental geometric properties of interacting surfaces used for light transfer computation.Many numerical applications such as realistic image synthesis require accurate and simple formula for the form factors from small oriented differential areas (treated as a point with a normal) to different geometrical objects; a disk was used in this paper. The exact analytic solution for the general point-to-disk form factor integral is used to develop more accurate numerical techniques for form factor integration for surfaces commonly in use. The improvements are illustrated with realistic image synthesis. 相似文献
97.
Non-stoichiometry, induced by exposure to oxygen and vacuum has been investigated for the uranium oxides UO2, U4O9 and U3O8 using X-ray photoelectron spectroscopy. Each stoichiometric uranium oxide is shown to display a unique X-ray photoelectron spectrum which can be altered quite dramatically by changes in stoichiometry and explained by a defect cluster model. 相似文献
98.
Recent research has suggested that the shell of an air-entrained void is important for resisting coalescence between air-voids and diffusion of gas from the surrounding fluid. The current paper describes the physical and chemical properties of an air-void shell during the first 2 h of hydration and chemical characteristics at 60 days. Results from this research suggest that the air-void shells found in air-entrained paste have varied physical properties and the crystalline material of these shells is largely made up of fine cement particles during the first 2 h of hydration. Observations of paste at 60 days of hydration suggest that the shell is made up of calcium silicate hydrate (C-S-H) with a morphology different from that in the bulk paste. 相似文献
99.
100.
Tyler Maher 《Critical reviews in food science and nutrition》2019,59(10):1619-1644
Dietary fat has been implicated in the rise of obesity due to its energy density, palatability and weak effects on satiety. As fat is a major contributor to overall energy intake, incorporating fat with satiating properties could potentially reduce energy intake. This review outlines the potential mechanisms, as far as we know, by which Medium-Chain Triglycerides (MCT), Conjugated Linoleic Acid (CLA), Short-Chain Fatty Acids (SCFA), Diacylglycerol (DAG), n-3 PUFA, and Small Particle Lipids, exerts their satiating effects. The evidence suggests that the lipid with the most potential to enhance satiety is MCT. SCFA can also promote satiety, but oral administration has been linked to poor tolerability rather than satiety. Data on the appetite effects of CLA is limited but does suggest potential. Research comparing these lipids to each other is also lacking and should be explored to elucidate which of these ‘functional lipids’ is the most beneficial in enhancing satiety. 相似文献