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991.
The present investigation was concerned with the implementation of an information system within a health care setting. A large number of staff required training on a new patient management information system (MIS). The aim of this study was to assess occupational differences on a number of psychological variables associated with MIS success. Computer anxiety was of primary concern due to its relationship to avoidance of computers. A total of 175 questionnaires were distributed, with 103 questionnaires being completed and returned for analysis (61.1%). It was found that clerical/administrative staff had significantly higher self-efficacy regarding computer use and more experience with computers. The nursing group experienced significantly more, computer anxiety, negative attitudes, and negative expectations than the clerical group. Self-efficacy was found to be the best predictor of computer related anxiety. The results have implications for MIS implementation strategies particularly in the areas of training and resource allocation. 相似文献
992.
BE Hoppel RM Weisskoff KR Thulborn JB Moore KK Kwong BR Rosen 《Canadian Metallurgical Quarterly》1993,30(6):715-723
An echo planar linewidth mapping technique, Shufflebutt, has allowed temporal measurements of changes in linewidth caused by static inhomogeneities (delta LWSI) and transverse relaxation rate (delta R2) in models of hypoxia and hypercapnia. We demonstrate these changes are due to intravascular susceptibility differences/(delta chi) between the blood and tissue. Contrast agent injections at a delta chi equivalent to that of deoxygenated blood showed a twofold difference between the contrast agent and physiological anoxia values. Hypercapnia decreased both delta LWSI and delta R2 consistent with an increase in blood oxygenation. We attribute these findings to constant oxygen extraction during an increase in blood flow, resulting in less deoxygenated venous blood and thus reduced delta chi. For in vivo perturbations we found that delta R2/delta R2' approximately 0.33, a ratio much different from that measured in whole blood phantoms (delta R2/delta R2' approximately 2). This demonstrates that signal changes in these studies are produced predominantly by dephasing of extravascular protons due to field inhomogeneities produced by intravascular deoxygenated hemoglobin (deoxyHb). 相似文献
993.
994.
Hoffman's (see 34: 7779) position concerning the independent contribution of a variable in the judgment process is examined by presenting several empirical examples. It is concluded that the concept of relative weight will not provide any information about the independent contribution of a predictor. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Truman L. Ward Audrey T. Gros R. O. Feuge 《Journal of the American Oil Chemists' Society》1959,36(12):667-671
Summary Six new glyceride esters of adipic acid were prepared, and their properties were determined. By the
Presented at the 49th Annual Meeting of the American Oil Chemists' Society, Memphis, Tenn., April 21–23, 1958.
One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S.
Department of Agriculture. 相似文献
996.
RM Moreau 《Canadian Metallurgical Quarterly》1980,125(3):439-441
997.
The effects of an isopropanol environment on the deformation characteristics of copoly (acrylonitrile-butadiene-styrene) (ABS) and poly (vinyl chloride) (PVC) have been investigated. Creep tests were performed in tension and torsion both in air and in isopropanol. It was noted that accelerated rates of creep were encountered during the tensile tests in isopropanol as compared with air but no differences were noted during the torsion tests. An explanation is proposed that the greatly increased creep strains encountered in tension result from diffusion of the fluid into the polymer. The rate of diffusion is controlled by changes in the free volume which occur on application of uniaxial tensile stresses. The existence of the fluid molecules in the polymer matrix reduce its local creep resistance and produce swelling, both of which are manifested as increased creep strains. The fact that no effects were noted during torsion tests (where the free volume remains constant) or when an unstressed specimen was immersed in the fluid indicates that no significant absorption occurs at the equilibrium (unstressed) free volume. 相似文献
998.
Diuretics are commonly prescribed for a wide variety of clinical problems, including hypertension, extracellular volume excess, and disorders of calcium metabolism. Although natriuresis with altered sodium balance is not always the therapeutic goal, this feature of the diuretics is essential for optimal results, irrespective of the clinical problem. 相似文献
999.
A quantitative treatment is presented for the absorption of polarized infra-red radiation at normal incidence by a transversely isotropic polymer film. In addition to the reflectivity correction, an approximate treatment of the internal field problem is also carried out. This is important where the polymer is of high polarizability. It is shown how the orientation and concentration of the absorbing species can be derived from experimental data. 相似文献
1000.
Summary The practical limits of the solubility of pure monostearin in various solvents at different temperatures has been determined
for isopropyl alcohol, ethanol, acetone, methanol, and commercial hexane. The synthetic method was employed, in which the
temperature of known quantities of solvent and solute was decreased until crystallization of the solute began. This temperature,
corrected for supercooling and heat loss to the surrounding bath, was taken as the equilibrium temperature between the known
weight of solute and the known weight of solvent.
The solubility-temperature data of monostearin in each of the various solvents are presented both graphically and in tabular
form.
A comparison of the solubility of monostearin in the various solvents at comparative temperatures indicates that its solubility
is greatest in isopropyl alcohol and decreases in the order ethanol, acetone, methanol, and hexane.
Presented at the 45th annual meeting of the American Oil Chemists' Society, San Antonio, Tex., April 12–14, 1954.
One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture. 相似文献