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41.
Used Bender-Gestalt recall scores and clinical evaluation of Bender protocols to predict organicity in 2 comparisons in a total of 89 Ss: normals vs premorbids for Huntington's disease and normals vs Ss already affected with Huntington's disease (mean ages, 31 yrs for normals and premorbids and 38 yrs for Huntington's Ss). Mean Bender recall scores significantly discriminated between normals and premorbids. Chi-squares reflecting predictive accuracy were significant for both comparisons using the Bender recall score but were nonsignificant for the predictions by clinical evaluations. Hit rates for the recall score prediction, however, were not much better than those for the clinical evaluation method and were too low for diagnostic evaluation of individual cases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
This paper investigates the methodology for the systematic optimisation of a low-cost transport piping network for distributed solar systems. In order to determine the range of power sizes for which this form of energy transport is economical, equations are developed to yield optimum engineering design parameters for steam-based energy transport in pipelines. A computer software package has been developed which gives the most cost effective layout of optimum networks, size of each pipe/insulation, percentage of the maximum pressure drop to the inlet pressure (% Δp), and percentage of the cost of energy transportation to the energy collected (% cost). Power station sizes of up to 84 MWe have been studied with collectors of area 300 m2 each. 相似文献
43.
44.
Investigated the effects of paternal deprivation on 248 4th-grade Mexican-American students. Drawings of the human figure--1 male and 1 female--were obtained from each S, following the procedures of the Goodenough-Harris Drawing Test. Ss were also administered Raven's Coloured Progressive Matrices and the Bender Gestalt Test. Each S was rated on degree of personal adjustment by his/her classroom teacher on a 4-point scale, ranging from well adjusted, no problems in relating to others, to serious maladjustment. Results show that father-present Ss obtained significantly higher Goodenough-Harris scores than father-absent Ss on both the male and the female figures drawn. The female figures drawn by the father-absent Ss had significantly fewer feminine attributes than those drawn by father-present Ss. Whereas teachers found father-present males and females and father-absent females fairly well adjusted, father-absent males were found to show significantly more signs of social and emotional maladjustment than all the other 3 groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
High-strength products made from atomized Al-Zn-Mg-Cu-Co alloy powders have good combinations of strength, ductility, resistance
to stress-corrosion cracking and fracture toughness. Powder Metallurgy (PJM) methods produce fine metallurgical structures
and compositions which cannot be produced by Ingot Metallurgy (IJM) methods.
Fine structures result from very rapid solidification and from the effect of fine dispersoids in restricting grain growth.
Stress-corrosion cracking (SCC) performance is favored by grain morphology of PJM products. Co2Al9 particles in PJM products are 0.02 to 2.0 μm spheroids occurring frequently on grain boundaries where they may serve several
functions in slowing SCC attack. Oxide particles are irregular shapes, 0.01 to 0.04 μm in size, occurring in clusters at grain
boundaries and in grain bodies. Some of the oxide particles are magnesium oxide and alter the environment in a SCC crack to
arrest attack. Porosity is not a significant factor in the structure of PJM products made by a vacuum compacting process.
P/M wrought products have superior combinations of high strength and stress-corrosion cracking resistance compared to IJM
7075 and 7050 alloys. While equaling the fracture toughness of 7075 alloy, the PJM products at present have somewhat lower
fracture toughness than 7050 alloy, due in part to a larger amount of second-phase particles in the form of Co2Al9 and oxide.
This paper is based on an invited presentation made at a symposium on “Advances in the Physical Metallurgy of Aluminum Alloys”
held at the Spring Meeting of TMS-IMD in Philadelphia, Pennsylvania, on May 29 to June 1, 1973. The symposium was co-sponsored
by the Physical Metallurgy Committee and the Non-Ferrous Metals Committee of TMS-IMD. 相似文献
46.
Dermal absorption of pesticides is a primary exposure route for agricultural workers, but is not well characterized. Current measurement techniques are either invasive, such as tape-stripping, or require extensive sample preparation or analysis time, such as urinary metabolite monitoring or wipe sampling followed by gas chromatography analysis. We present the application of a noninvasive, spectroscopic approach for the measurement of pesticide absorption into skin. Attenuated total reflectance infrared spectroscopy (ATR-IR) was used to monitor directly the absorption of two pesticides--captan and azinphos-methyl--in ten volunteers over 20 min under occlusive conditions. We found substantial variability in absorption across subjects. Our results were comparable to those measured by the more traditional method of wipe-sampling followed by extraction and gas chromatography analysis. Multivariate data analysis, in the form of multivariate curve resolution (MCR), is a novel addition to this type of experiment, yielding time-resolved information unachievable by standard methods. These data are potentially more informative than the monitoring of blood or urinary metabolites because they can be acquired in essentially real-time, allowing observations of pesticide absorption on a rapid timescale rather than over hours or days. 相似文献
47.
Chao TH Lam T Vong BG Través PG Hortelano S Chowdhury C Bahjat FR Lloyd GK Moldawer LL Boscá L Palladino MA Theodorakis EA 《Chembiochem : a European journal of chemical biology》2005,6(1):133-144
The synthesis and the biological evaluation of a new family diterpenes are presented. The synthetic studies were inspired by the structural framework of acanthoic acid (1) and yielded a family of compounds that were evaluated as anti-inflammatory agents. Among them, compounds 2, 10, 12, and 16 exhibited a very low nonspecific cytotoxicity and inhibited the synthesis of TNF-alpha with greater than 65 % efficacy at low micromolar concentrations. Cytokine-specificity studies revealed that these compounds also inhibited the synthesis of the proinflammatory cytokines IL-1beta and IL-6, while inhibition of IL-1ra and IL-8 synthesis was marginal and only occurred at high concentrations. Further studies, through EMSA and Western blot analyses, indicated that these compounds decreased the extent of phosphorylation of IkappaBalpha; this suggests that they exert their anti-inflammatory profile by inhibiting NF-kappaB-mediated cytokine synthesis. These findings imply that these diterpenes represent promising leads for the development of novel anti-inflammatory agents. 相似文献
48.
49.
In this paper a nonlinear analysis of a multifilter phase-lock loop (MPLL) by using the method of "harmonic balance" is presented. The particular MPLL considered has a low-pass filter and a bandpass filter in parallel. An analytic expression for the relationship between the input signal phase deviation and the phase error is determined for sinusoidal FM in the absence of noise. The expression is used to determine bounds on the proper operating region for the MPLL and to investigate the "jump phenomenon" previously observed. From these results the proper modulation index, modulating frequency, etc., used for the design of an MPLL is determined. Data for the loop unlock boundary obtained from the theoretical expression are compared to data obtained from analog computer simulations of the MPLL. 相似文献
50.
In the course of isolating and analyzing the fatty acid methyl esters (FAME) from steelhead trout (Salmo gairdneri) eggs and sac fry, a component was found on gas liquid chromatography to have a retention time longer than any characteristic
polyunsaturated fatty acid previously encountered in trout. Subsequent purification and analysis demonstrated this component
to be cholesterol. Thus, cholesterol and related compounds can interfere in the analysis of FAME when the methyl esters are
prepared by transesterification. 相似文献