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31.
Examined the impact of increasing the percentage of hires (above the T. A. Cleary [1968] fair-hiring level) from minority groups with demonstrated lower average job performance. Increased minority hiring resulted in only a small performance loss, even when minority hiring exceeded the minority applicant representation. However, when minorities were hired at a rate equal to or greater than their applicant representation, the expected performance loss among the hired minorities was much greater than performance loss across all hires. More important, the discrepancy in performance between majority and minority hires increased as minority hiring increased. With minority hiring above the level of minority applicant representation, this discrepancy exceeded the population difference in performance between the 2 groups. These findings suggest additional considerations when raising minority hiring above minority applicant representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
AF da Silva P McCollum T Szymanska L de Cossart 《Canadian Metallurgical Quarterly》1996,83(10):1370-1372
A total of 700 patients who had carotid endarterectomy (CEA) in the UK and Ireland during a 6-month interval between March and August 1994 were studied prospectively. Some 108 patients (15.4 per cent) had a contralateral internal carotid artery occlusion. Previous reports have shown an associated stroke rate of about 10 per cent in these patients. This study assessed complications and outcome for patients undergoing CEA with contralateral internal carotid artery occlusion compared with those without. The indications for surgery were comparable between the two groups although the patients with occlusion had a slightly higher incidence of arrhythmia and stroke. Intraoperative shunts were used in a significantly higher proportion of those with occlusion (83.3 versus 64.7 per cent, P = 0.0001). The combined death and stroke rate for patients with occlusion was 5.6 per cent compared with 2.4 per cent for the remainder (P not significant). On the basis of the present data, CEA with a contralateral carotid artery occlusion carries only a slight increase in the rate of postoperative stroke and death. This increase was not statistically significant and is lower than that reported previously. 相似文献
33.
B. Herreros G. Lifante A. Kling J.C. Soares M.F. da Silva P.D. Townsend P.J. Chandler J. Olivares J.M. Cabrera 《Optical Materials》1996,6(4):281-286
We present a structural study of two Nd3+/MgO codoped LiNbO3 waveguides fabricated by two different methods: ion-implantation and proton-exchange. Rutherford backscattering spectrometry in combination with channelling was used to study the influence of the waveguide fabrication method on the possible modification of the LiNbO3 crystal structure within the waveguiding layer. The results show that the ion-implanted waveguide mainly maintains the same properties as the virgin crystal, apart from a deterioration of a thin surface layer, whilst the proton-exchanged waveguide exhibits a quite different behaviour, although its surface is less damaged. 相似文献
34.
P Cruz R Almeida M Gon?alves G Marote J Silva C Cavaleiro V Jacinto 《Canadian Metallurgical Quarterly》1994,7(5):277-280
Ocular paresis is a usual diagnosis in neuro-ophthalmologic consultation, and its aetiology is indeed a challenge. The authors studied 3400 records concerning this consultation, between 1982 and the third quarter of 1993. During this period 221 cases with ocular paresis were selected. During this retrospective study we point out the following items: the cranial nerve affected; the neuro-ophthalmologic semiology; the aetiology and clinical evolution, according to the age groups. From 221 cases selected, 111 were paresis from the VIth pair (50.2%), 88 from the IIIrd pair (39.8%), 14 multiple paresis (6.4%) and 8 paresis from the IVth pair (3.6%). The most frequent complaint was diplopia (> 90%). As far as the aetiological diagnosis is concerned, this was easier to establish in patients > 50 years of age. In this age group the most usual aetiology was vascular and traumatic pathologies. In younger patients the most frequent pathologies were traumatic and tumoral. The prognostic was better in the vascular group, the paresis recovery being > 50% in all other pathologies, except the tumoral one. 相似文献
35.
Huseyin Selcuk Jeosadaque J Sene Marc A Anderson 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(9):979-984
This study addresses the removal of humic acid (HA) dissolved in an aqueous medium by a photoelectrocatalytic process. UV254 removal and the degradation of color (Vis400) followed pseudo‐first order kinetics. Rate constants were 1.1 × 10?1 min?1, 8.3 × 10?2 min?1 and 2.49 × 10?2 min?1 (R2 > 0.97) for UV254 degradation and 1.7 × 10?1 min?1, 6.5 × 10?2 min?1 and 2.0 × 10?2 min?1 for color removal from 5 mg dm?3, 10 mg dm?3 and 25 mg dm?3 HA respectively. Following a 2 h irradiation time, 96% of the color, 98% of the humic acid and 85% of the total organic carbon (TOC) was removed from an initial 25 mg dm?3 HA solution in the photoanode cell. Photocatalytic removal on the same photoanode was also studied in order to compare the two methods of degradation. Results showed that the photoelectrocatalytic method was much more effective than the photocatalytic method especially at high pH values and with respect to UV254 removal. The effect of other important reaction variables, eg pH, external potential and electrolyte concentration, on the photoelectrocatalytic HA degradation was also studied. Copyright © 2003 Society of Chemical Industry 相似文献
36.
A difficulty in reliability modeling is how to capture the impact of all of the various reliability defect types. The general approach to optimizing burn-in that we describe in this article addresses a multiple-defect environment. The approach has four main parts: (i) modeling the product's failure rate distribution, (ii) establishing the Pareto distribution of reliability defects, (iii) assessing the kinetic information of each reliability defect, and (iv) estimating the DPPM under product use conditions. This article compares and contrasts the acceleration effects of various extrinsic defects found in 130- and 90-nm CMOS technology products. 相似文献
37.
38.
The proteasome is a multi-subunit protease responsible for the production of peptides presented by major histocompatibility complex class I molecules. Accumulated evidence indicates that, upon stimulation with interferon-gamma (IFN-gamma), three beta-type subunits, designated LMP2, LMP7, and PSMB10, are incorporated into the 20S proteasome by displacing the housekeeping beta-type subunits designated PSMB6, PSMB5, and PSMB7, respectively. These changes in the subunit composition appear to facilitate class I-mediated antigen presentation, presumably by altering the cleavage specificities of the proteasome. In the present study, we determined the organization of the mouse gene Psmb5, coding for the PSMB5 subunit. Psmb5 is made up of three exons, spanning approximately 5 kilobases. Its exon-intron organization differs radically from those of the other IFN-gamma-regulated, beta-type subunit genes including Lmp7 with which Psmb5 is believed to share an immediate common ancestor. The structure of the mouse Psmb5 gene is identical to that of its recently characterized human counterpart. Thus, the unique organization of the gene coding for the PSMB5 subunit appears to have been established before mammalian radiation. As well as the Psmb5 gene, the mouse genome contains a processed pseudogene designated Psmb5-ps. Interspecific backcross mapping showed that Psmb5 maps close to the Gtrgal2 locus on chromosome 14 and that Psmb5-ps is located in the vicinity of the Psme3 locus on chromosome 11. These results were confirmed by fluorescent in situ hybridization analysis that localized Psmb5 to band C2 to proximal D1 of chromosome 14 and Psmb5-ps to band D of chromosome 11. 相似文献
39.
Qing-Huo Liu Anderson B. Weng Cho Chew 《Geoscience and Remote Sensing, IEEE Transactions on》1994,32(3):494-498
The authors formulate and implement a numerical mode-matching (NMM) method to model electrode-type resistivity tools in invaded thin beds. The authors derive the low-frequency approximation of the Maxwell's equations to obtain the partial differential equation for the potential field. The new NMM program is validated by comparing the numerical results with those obtained from other dc programs. It is found that this new program is much faster than the program using the finite-element method (FEM), and hence is useful for routine interpretation of resistivity logs and for inversion 相似文献
40.
Simoes A.S. Silva M.M. Anunciada A.V. 《Industrial Electronics, IEEE Transactions on》1994,41(2):251-255
A boost type converter is described that is suitable for low-voltage DC-supply of fluorescent lamps. It has inherent lamp current limitation (ballast action) and provides the high voltage pulses and electrode heating that are required for igniting the lamp. The proposed circuit is applicable in automotive, emergency, and portable light sources.<> 相似文献