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1.
This study aimed to better understand the impact of business trips on the traveler, the family, and the organization; to learn about maximizing the positive aspects of business travel; and to suggest measures to prevent and manage travel stress. Thirty-five business travelers (American, Israeli, and Swedish) were interviewed about the costs and benefits of their traveling, with a focus on gaining insight into coping strategies. Content analysis of the interviews showed that trips consist of 4 phases--(a) pretrip, (b) journey, (c) stay, and (d) posttrip--and that each phase is characterized by different coping strategies. Business travelers reported using proactive individual and organizational coping strategies in the pretrip phase and a combination of proactive and reactive coping strategies in the other phases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
F Hammarqvist B Westman CE Leijonmarck K Andersson J Wernerman 《Canadian Metallurgical Quarterly》1996,119(4):417-423
A number of studies have localized CGRP to nerves in the cornea and iris, and it is thought that CGRP, along with other neuropeptides, is involved in pain sensation. It is also possible that CGRP could mediate trophic influences between nerve endings and corneal epithelium. This investigation utilized an in vitro rabbit corneal whole mount preparation to study the effect of topical 2.5 microM CGRP application on epithelial wound healing rates of 5 mm diameter epithelial wounds. CGRP (2.5 microM) was applied topically to 5 mm epithelial wounds at 0, 4, 16, 20, 24, 28, 40, 44, 48, 52, 56, 64, 68, and 72 hours after wounding and healing was visualized with fluorescein. CGRP was found to increase the epithelial wound healing rate by 25%, from 51 +/- 3 microns/hr for the control corneas, to 64 +/- 2 microns/hr for CGRP-treated corneas (mean +/- standard error, n = 10). Histological examination of the corneas following healing showed that the epithelium of the CGRP-treated corneas healed in a similar manner as in the control corneas. These findings may have clinical utility for the understanding and treatment of corneal and other epithelial wounds. 相似文献
3.
Smokeless tobacco use is a significant health risk for carcinoma of the oropharynx, and has a high prevalence in the southern United States. To evaluate the potential demand for a smokeless tobacco cessation program, we surveyed patients attending the General Medicine Clinic of a Veterans Affairs Medical Center. The prevalence of smokeless tobacco use was 5.8%, which did not justify creation of a clinic-based cessation program. Since we observed adults using smokeless tobacco as a means to reduce or stop their smoking, smoking cessation programs should include counseling against smokeless tobacco use. 相似文献
4.
Cellulose hydrogels have been synthesized by reacting solutions of cellulose xanthate with different amounts of epichlorohydrin (0–24% w/w on cellulose) after which the cellulose was regenerated. The weight fraction of crystalline cellulose, determined by density measurements, decreases with the extent of chemical crosslinking and was estimated to vary between 30 and 42% for dry gels. The degree of equilibrium swelling in water of the prepared hydrogels varied between 3.05 and 6.33 g water/g dry gel (g/g). The degree of swelling decreases with increasing chemical crosslinking. As a result of the irreversible changes occurring during drying, the degree of swelling in water can be reduced down to 0.74 g/g. According to density gradient column measurements, the partial specific volume of water is 0.865 cm3/g at water contents below 0.13 g/g. It is suggested that water having this partial specific volume is the specific hydration water. At higher water contents, the partial specific volume of gel water equals the specific volume of bulk water. It is implicit in the interpretation of the density data in terms of a two state model of gel water that the crystallinity of cellulose is independent of the water content. Depending on the degree of swelling, heat treatment resulted in either an irreversible increase or decrease of the degree of swelling. 相似文献
5.
Davidson Oranit B.; Eden Dov; Westman Mina; Cohen-Charash Yochi; Hammer Leslie B.; Kluger Avraham N.; Krausz Moshe; Maslach Christina; O'Driscoll Michael; Perrewé Pamela L.; Quick James Campbell; Rosenblatt Zehava; Spector Paul E. 《Canadian Metallurgical Quarterly》2010,95(5):953
A rigorous quasi-experiment tested the ameliorative effects of a sabbatical leave, a special case of respite from routine work. We hypothesized that (a) respite increases resource level and well-being and (b) individual differences and respite features moderate respite effects. A sample of 129 faculty members on sabbatical and 129 matched controls completed measures of resource gain, resource loss, and well-being before, during, and after the sabbatical. Among the sabbatees, resource loss declined and resource gain and well-being rose during the sabbatical. The comparison group showed no change. Moderation analysis revealed that those who reported higher respite self-efficacy and greater control, were more detached, had a more positive sabbatical experience, and spent their sabbatical outside their home country enjoyed more enhanced well-being than others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
A. E. R. Westman 《Journal of the American Ceramic Society》1929,12(9):585-595
The forces which act when clay is mixed with water and when water is removed from wet clay by evaporation have received little study. For this reason, very little definite information regarding the internal mechanism of the drying of clayware is available. In this paper, the writer reviews the experiments and theories of Pukall, Terzaghi, Dixon, etc., lists some of the forces which may act when ware is drying, and defines an important force which he calls “capillary suction.” A simple experiment is described, by means of which this force can be readily demonstrated. The development and final form of an apparatus for measuring the capillary suction of ceramic materials is described and data obtained from measurements on a ball clay, a kaolin, flint, feldspar and mixtures of these substances are reported. Capillary suction decreases rapidly with increase in the flint and feldspar of a ceramic body. By utilizing the capillary suction produced by evaporation of water from a clay surface, water at atmospheric pressure has been made to enter a steel bomb in which the gas pressure was maintained at 200 lbs. per square inch. 相似文献
7.
THE EFFECT OF MECHANICAL PRESSURE ON THE IMBIBITIONAL AND DRYING PROPERTIES OF SOME CERAMIC CLAYS,I*
A. E. R. Westman 《Journal of the American Ceramic Society》1932,15(10):552-563
A number of ceramic clays in the plastic condition were held between water-permeable pistons under mechanical pressure of from 200 to 20,000 pounds per square inch in contact with water at atmospheric pressure until equilibrium was reached; the water in the pistons was removed by compressed air, the pressure released. and the moisture content, density, drying shrinkage, and other properties of the clays determined. In every case, the moisture content and drying shrinkage decreased with increasing pressure and with some clays at high pressures expansion occurred on drying. Rather complete data are given for a number of clays and their theoretical and practical significance is discussed. 相似文献
8.
A transmission electron microscope study has been made of a silicon nitride component with 6 w/o yttrium oxide as a sintering aid hot isostatically pressed (HIP) with an encapsulation glass of borosilicate. The TEM study concentrated on the interface region between ceramic and glass. Two different types of hexagonal boron nitride were formed near the interface. One, with a textured structure, seemed to nucleate heterogeneously on the surfaces of silicon oxynitride grains. The (001) planes of the crystals extended outwards, giving a thickness of approximately 0.5 microns. The other type formed as hexagonally shaped grains separate from the first type and appeared to have grown as several segments in different directions around a nucleus. In each segment BN layers are parallel to each other and perpendicular to their common [001]BM direction. This second type of BN crystal was also detected a little further from the surface within the silicon nitride. The volume fraction of additive glassy phase tended to be lower in this surface region than in the bulk. Possible mechanisms of prevention of encapsulation glass penetration into the porous ceramic component during HIP were discussed. 相似文献
9.
In this introduction, the authors discuss work–family research in the context of occupational health psychology (OHP), describe the special contributions of articles in this special issue, and outline directions for the next generation of research in the field of OHP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
A. E. R. Westman 《Journal of the American Ceramic Society》1928,11(9):715-723
Attention is drawn to an error in the equation for calculating linear shrinkage (per cent of dry length) from volume shrinkage (per cent of dry volume) which was given in the Report of the Committee on Standards, American Ceramic Society , Year Book, 1921–22. In order to avoid errors due to the use of incorrect equations, in future work, the more useful equations for making the ordinary shrinkage, expansion, and design calculations are derived and tabulated. To facilitate numerical computation, four figure tables are given by means of which the labor involved in the more usual ceramic calculations involving shrinkage and expansion can be greatly reduced. The use of the equations and tables is explained and illustrated by means of examples. 相似文献