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排序方式: 共有613条查询结果,搜索用时 15 毫秒
81.
Growing numbers of employees are leaving the traditional workplace and daily commute behind for work at home or in satellite telecenters close to home. This article provides IS managers with tips for establishing successful telecommuting programs and managing telecommuters. 相似文献
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83.
Spielberger Charles D.; Auerbach Stephen M.; Wadsworth Allen P.; Dunn Thomas M.; Taulbee Earl S. 《Canadian Metallurgical Quarterly》1973,40(1):33
Evaluated the stress effects of major surgery on 26 white male patients. The State-Trait Anxiety Inventory (STAI) and Kincannon's Mini-Mult version of the MMPI were given 18-24 hr. before surgery and 3-9 days postsurgery after the S was informed he was recovering without complications. Mean STAI A-State scores were much higher prior to surgery than after; STAI A-Trait scores were essentially the same. Patients with high- and low-A-Trait scores showed similar presurgery-postsurgery changes in A-State. Scores on the Mini-Mult were essentially unchanged by the stresses associated with surgery. Results indicate that the threat of imminent surgery produced elevations in anxiety as an emotional state, but did not affect anxiety proneness (A-Trait). (27 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
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86.
"A representative sample of the resident population of adults in the United States was interviewed about their feelings of distress in different life areas: perceptions of the self; symptoms of distress; adjustment in marriage parenthood, and work." Factor analysis of these data revealed the presence of 5 separate dimensions through which distress may be expressed: anxiety, unhappiness, sense of social inadequacy, lack of identity, and physical ill health. Men and women were distinguished by distress being expressed through physical ill health for men, psychological symptoms for women. The study indicates that psychological adjustment is multi-rather than unidimensional. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Mastering supramolecular self-assembly to a similar degree as nature has achieved on a subcellular scale is critical for the efficient fabrication of complex nanoscopic and mesoscopic structures. We demonstrate that active, molecular-scale transport powered by biomolecular motors can be utilized to drive the self-assembly of mesoscopic structures that would not form in the absence of active transport. In the presented example, functionalized microtubules transported by surface-immobilized kinesin motors cross-link via biotin/streptavidin bonds and form extended linear and circular mesoscopic structures, which move in the presence of ATP. The self-assembled structures are oriented, exhibit large internal strains, and are metastable while the biomolecular motors are active. The integration of molecular motors into the self-assembly process overcomes the trade-off between stability and complexity in thermally activated molecular self-assembly. 相似文献
88.
Determined the effectiveness of single isolated vowels as auditory stimuli in eliciting perceptual illusory changes in ss, a phenomenon referred to by R. M. Warren (see pa, vol. 36:3gh49w) as the "verbal transformation effect." 3 vowels, /i/, /ae/, and /u/, were individually presented to a group of 24 19-24 yr. Old normal listeners in a single experimental session. Each vowel was repeatedly presented by means of headphones for a period of 5 min. Results indicate that single isolated vowels are capable of eliciting verbal transformations in normal listeners. However, the transformations reported often differed from those obtained in previous studies which used more phonetically complex auditory stimuli. The nature of the verbal transformations, average number of alternate forms perceived and transitions employed, and average number of repetitions of the stimuli prior to the onset of the ss' 1st verbal transformations are discussed. Comparisons with findings of previous investigations are provided. (french summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Peter Donkin Sheila V. Mann Eric I. Hamilton 《The Science of the total environment》1981,19(2):121-142
PCB, DDT, DDE, dieldrin and total non-polar organohalogen residues have been determined in the blubber-lipid of grey seals (Halichoerus grypus) sampled during the 1972 breeding season (November) at the Farne Islands off the north eastern coast of England. PCBs were analysed by gas-liquid chromatography linked to a chlorine- and carbon-selective microwave plasma detector and total organohalogen residues were determined by microcoulometry.Total organohalogen residues were negatively correlated with blubber thickness and positively correlated with age in males (aged 1 to 24 y) and females (aged 5 to 38 y). However, the correlation of blubber-lipid residue with age in males depended upon the inclusion of immature (aged < 6 y) animals, and in females reflected only a small residue increment. The mean blubber organohalogen concentration of the males was significantly greater than that of the females. PCB and DDT group residue concentrations were significantly correlated.PCB, DDT, DDE and dieldrin were detected in the liver of mother/foetus pairs demonstrating transplacental movement of these residues.The possibility of the condition of the seals at breeding time influencing residue levels and of these residues influencing the health of the population is discussed. 相似文献
90.
A method was developed for the rapid determination of the initial velocity of the desaturation of saturated fatty acids. In
the reaction, DPNH was a more efficient electron donor than TPNH. Fatdeficient rats have a 2.5-fold greater level of acyl
desaturase per milligram of liver microsomal protein than did animals fed lab chow. Increasing the chain length of the acyl
substrate from 10∶0 to 18∶0 increases the rate of monoene formation, but 19∶0 is desaturated at a rate lower than that for
15∶0. The energy of activation (Ea) for the overall desaturation reaction has been determined for 12∶0 through 19∶0. The Ea
values for desaturation of 13∶0 and 16∶0 are markedly lowr than for the other acids. An interaction between the alkyl chain
of the substrate and polyunsaturated acids of the microsomal membrane-bound phospholipids is postulated to explain the recurring
3-carbon pattern of the relative reaction rates of the various acyl substrates. 相似文献