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Considers the progress, or lack thereof, that has been made in the development of ability testing. It is argued that the lack of progress is best understood in terms of the consumer market for tests and what it seeks. Current tests, inadequate though they may be, largely respond to the demands of test consumers. However, these demands are showing some signs of changing, and the time has come for test publishers to take these signs seriously, rather than continuing to produce products that represent changes in superficial appearance more so than in substance. Although the available alternatives to conventional tests have often been inadequate themselves, they do point the way toward measurement of skills beyond basic memory and analytical abilities, namely, skills such as creative and practical aspects of intelligence, as well as thinking and learning styles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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LG Farkas 《Canadian Metallurgical Quarterly》1996,33(1):10-8; discussion 19-22
Experience, based on anthropometric examination of over 1000 children with facial syndromes and more than 2400 healthy subjects of both sexes and various ages, has led me to diverge in some points from the more usual views found in the physical anthropologic literature. The purpose of this paper is to discuss the major controversial topics associated with anthropometric measurement. These include the problems associated with formation of a representative population sample, the relative validity of longitudinal and cross-sectional studies, the interpretation of intraobserver and interobserver testings, and the questionable judgments of mensurative skill in clinical practice. The factors influencing the accuracy of anthropometric measurements, definitions of both the consistent and less reliable measurements, and the duration of validity of anthropometric normative data are also discussed.  相似文献   

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The tenets of a cognitive, motivational model called hope theory (Snyder et al., 1991) are reviewed, along with the two accompanying instruments for measuring hope in children and adolescents. More than a decade of research on hope theory as it relates to students, teachers, and schools is summarized. Likewise, the applications of hope theory for school psychologists are reviewed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

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Superelastic NiTi was subjected to simultaneous neutron diffraction and uniaxial compressive cycling between 10 and 980 MPa. The objective was an in-situ investigation of the evolution of the stress-induced, reversible transformation between austenite and martensite, to determine the cause of the changes in the macroscopic stress-strain response with cycling. Rietveld refinement was used to analyze the neutron spectra and quantify the phase fraction, texture, and elastic strain. The average phase strain in the mechanically loaded austenite (at a given stress) remained unaltered during the 100 load-unload cycles. However, differences in both the volume fraction and texture of austenite and martensite were noted as cycling progressed, suggesting that these factors are responsible for the changes in the macroscopic stress-strain response of NiTi with mechanical cycling.  相似文献   

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We determined carnitine concentrations in blood and in liver and abdominal muscle biopsy specimens in 13 men and 16 women undergoing elective surgery (mostly gallbladder removal). The data suggest that the carnitine pools of plasma and erythrocytes are different. The erythrocytes show a higher acylcarnitine concentration than does plasma (P < 0.001). Several reference bases for values in tissues have been used--dry weight, noncollagen protein (NCP), and DNA--because these may be differently influenced by disease. In liver specimens, the quotient NCP (g)/DNA (g) was significantly higher in men, 54.4 +/- 6.3 (mean +/- SD), than in women, 47.7 +/- 7.0 (P < 0.01). Liver total carnitine content in relation to DNA was significantly higher in men than in women: 0.29 +/- 0.06 vs 0.22 +/- 0.08 mmol/g DNA (P < 0.01). Free carnitine content was significantly higher in men than in women independently of the reference base, e.g., 3.7 +/- 1.0 mumol/g NCP for men vs 2.9 +/- 1.0 for women (P < 0.05). No difference was found between the sexes in the abdominal muscle carnitine content, 20.6 +/- 6.7 mumol/g NCP for men vs 17.9 +/- 5.0 for women. Our study establishes control ranges, thereby providing an important basis for studies of patients with abnormal carnitine metabolism.  相似文献   

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Superelastic NiTi was subjected to simultaneous neutron diffraction and uniaxial compressive cycling between 10 and 980 MPa. The objective was anin-situ investigation of the evolution of the stress-induced, reversible transformation between austenite and martensite, to determine the cause of the changes in the macroscopic stress-strain response with cycling. Rietveld refinement was used to analyze the neutron spectra and quantify the phase fraction, texture, and elastic strain. The average phase strain in the mechanically loaded austenite (at a given stress) remained unaltered during the 100 load-unload cycles. However, differences in both the volume fraction and texture of austenite and martensite were noted as cycling progressed, suggesting that these factors are responsible for the changes in the macroscopic stress-strain response of NiTi with mechanical cycling. R. VAIDYANATHAN, formerly Postdoctoral Associate, Laboratory for Experimental and Computational Micromechanics, Massachusetts Institute of Technology  相似文献   

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The issue of the relative merit of biomarkers and alternative measures of exposure arises most commonly in the context of epidemiological studies aimed at hazard detection and quantification. When exposures are from biological agents, biomarkers are usually the first and often the only justifiable choice. In general, however, the relative merit of different types of exposure measurements need to be evaluated on a case-by-case basis. Biomarkers may be affected by random errors, time-related sampling errors, physiological confounding and disease-induced differential error, all of which need to be explicitly evaluated before embarking on the use of a biomarker in a full-scale epidemiological study. Random errors affecting biomarkers may be reduced by replication or combination of measurements, or both. Alternative measurements of exposure can be evaluated against a biomarker when there is adequate evidence for regarding the marker as the true measure of a biologically relevant exposure.  相似文献   

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Modified coulometric titrations on the galvanic cell: O in liquid Bi, Sn or Ge/ZrO2( + CaO)/Air, Pt, were performed to determine the oxygen activities in liquid bismuth and tin at 973, 1073 and 1173 and in liquid germanium at 1233 and 1373 K. The standard Gibbs energy of solution of oxygen in liquid bismuth, tin and germanium for 1/2 O2 (1 atm) →O (1 at. pct) were determined respectively to be ΔG° (in Bi) = −24450 + 3.42T (±200), cal· g-atom−1 = − 102310 + 14.29T (±900), J·g-atom−1, ΔG° (in Sn) = −42140 + 4.90T (±350), cal· g-aton−1 = −176300 + 20.52T (± 1500), J-g-atom−1, ΔG° (inGe) = −42310 + 5.31 7 (±300), cal·g-atom−1 = −177020 + 22.21T(± 1300), J· g-atom−1, where the reference state for dissolved oxygen was an infinitely dilute solution. It was reconfirmed that the modified coulometric titration method proposed previously by two of the present authors produced far more reliable results than those reported by other investigators. TOYOKAZU SANO, formerly a Graduate Student, Osaka University  相似文献   

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Self-measurement of blood glucose is part of the daily routine for patients with diabetes, and healthcare professionals use these values for therapy and treatment. Healthcare providers are encouraging patients with insulin-dependent diabetes to test their blood glucose level four to six times a day to effectively manage their disease and significantly reduce the incidence of serious and costly complications. Unfortunately, people with diabetes test less than once a day on average, associating this noncompliance with pain associated with drawing blood from the finger. Glucose-monitoring techniques are under study that would allow body fluids other than blood to be used in a painless or almost painless manner. These new technologies could lead to a revolutionary advance in the treatment of diabetes, and the current research and development can now be reviewed.  相似文献   

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Intensity modulation of electron beams is one step towards truly conformal therapy. This can be realized with the MM50 racetrack microtron that utilizes a scanning beam technique. By adjusting the scan pattern it is possible to obtain arbitrary fluence distributions. Since the monitor chambers in the treatment head are segmented in both x- and y-directions it is possible to verify the fluence distribution to the patient at any time during the treatment. Intensity modulated electron beams have been measured with film and a plane parallel chamber and compared with calculations. The calculations were based on a pencil beam method. An intensity distribution at the multileaf collimator (MLC) level was calculated by superposition of measured pencil beams over scan patterns. By convolving this distribution with a Gaussian pencil beam, which has propagated from the MLC to the isocentre, a fluence distribution at isocentre level was obtained. The agreement between calculations and measurements was within 2% in dose or 1 mm in distance in the penumbra zones. A standard set of intensity modulated electron beams has been developed. These beams have been implemented in a treatment planning system and are used for manual optimization. A clinical example (prostate) of such an application is presented and compared with a standard irradiation technique.  相似文献   

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