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991.
This paper presents an analysis of the interactions among multiple human bodies, modeled by multilayered cylinders, exposed to microwaves. Cylinders are used because it is very difficult to compute the whole-body average specific absorption rate (SAR) at higher frequencies using a realistic human model. The average SAR is numerically discussed for a typical case of the linear array of two and three adult body models when the wave is vertically incident to the array. 相似文献
992.
C Hornstein P Richter A Mortimer A Will A Beuth I Müller-Wulff H Sauer 《Canadian Metallurgical Quarterly》1998,69(3):243-248
Wound contraction is thought to be independent of site, and circular full-thickness skin wounds are though not to contract completely. To verify these statements four circular full-thickness skin wounds were created on each side of eight pigs and randomised to treatment with either split-thickness skin grafts, or healing by secondary intention under a hydrocolloid dressing. Time to healing, contraction, and final scar shape were evaluated. The median healing time was 12 days (range 6-18) in the grafted wounds and 30 days (range 15-45) in the secondarily healing wounds. There were significant differences in healing time between the different sites on the pigs. In the secondarily healing group, medial-caudal wounds healed in 21 (15-21) days compared with lateral wounds which healed in 36 (21-45) days (p < 0.005), while no differences were found in the grafted group. There was a clear relationship between site and contractility and shape of the scars in both treatment groups. Scars located on the lateral-caudal aspect of the pig were predominantly round and contracted only slightly. Scars located on the lateral aspect of the pig tended to be oval. Contraction was greatest in the medial scars and least in the lateral scars. Median contraction was 33% (range -2-63) in skin grafted wounds and 64% (range 42-82) in secondarily healed wounds. This randomised experiment showed that extent of wound contraction is dependent of site, and that circular wounds do heal with contraction. 相似文献
993.
S Lupien R Richter SC Risch A Mirow JC Gillin RL Hauger 《Canadian Metallurgical Quarterly》1995,58(1):23-35
Recent studies performed with depressed patients and normal subjects suggest that corticosteroids may alter dopaminergic activity. We measured the time course of the interaction between corticosteroid and plasma homovanillic acid (HVA) levels in 10 young healthy subjects after the administration of 2 mg of dexamethasone in session 1 and after the administration of 4.5 g of metyrapone in session 2. Plasma levels of adrenocorticotropic hormone (ACTH), 11-desoxycortisol, cortisol, HVA, and prolactin (PRL) were measured at 08:00, 09:00, 12:00, 15:00, and 16:00 h on a baseline day and during both drug-administration sessions. Dexamethasone administration resulted in a significant decrease in plasma levels of ACTH, 11-desoxycortisol, and cortisol at all time points and to a significant decrease in PRL secretion in the early morning. Plasma HVA levels were unchanged after dexamethasone administration. Metyrapone administration resulted in a significant decrease in cortisol levels and a significant increase in ACTH and 11-desoxycortisol levels. Plasma HVA levels were significantly increased in the early morning, while PRL levels were unaltered. These results are discussed in relation to the neurochemical and behavioral changes associated with steroid administration and interpreted with regard to a possible association between HVA and PRL in the effects of corticosteroids on dopaminergic activity. 相似文献
994.
995.
M Díaz Gómez CL Ramos Acosta J Rico Sevillano M Robayna Curbelo J Alvarez Alvarez 《Canadian Metallurgical Quarterly》1997,20(231):11-14
One of the important tasks for a nurse is to insure that the newborn receives all the nourishment that it needs. A well fed baby is healthier, experiences a shorter hospital stay and develops a stronger bond with its mother. To prove this point a study was performed on a group of low birth weight newborns (free of other pathological symptoms) to compare nutrition against hospitalization time. 85 children of both sexes were divided into 3 groups: premature but of normal gestational size, premature but small for gestational size, and full term but small for gestational size; all had a birth weight superior to 2 kilos and were examined postpartum on their first and third week. The groups were then subdivided into 2 groups: one received only artificial milk formula and the other group received their mothers' milk through a bottle. The children that drank the maternal milk required fewer days in the hospital (18 +/- 6 days versus 27 +/- 7 days for those drinking only formula) and had a smaller percentage of weight loss after birth (3.7 +/- 2.0% versus 5.2 +/- 2.9%), demonstrating a significant difference in their overall health. 相似文献
996.
X-Ray Stress Measurements on Ti48Al2Cr Titanium Aluminide Material Stresses in specimens of Ti48Al2Cr material with various microstructures and surface conditions were measured by X-ray diffraction. The measurements were performed on the (224)/(422) twin peak of the γ-phase with CuKα-radiation by means of a position sensitive detector with metal wire. Depending on the mashining condition of the surface residual stresses between ca. – 1300MPa (compression) and + 500MPa (tension) were found. The X-ray elastic constants – s1 and 1/2 s2 were determined with flat specimens subjected to four point bending stresses. Results and measuring conditions are discussed with respect to problems with coarse grain, titanium fluorescence, peak selection and long measuring times. 相似文献
997.
A. Pia?tkowska J. Jagielski G. Gawlik W. MatzE. Richter M. MozeticA. Zalar 《Wear》2003,254(10):1037-1041
The relations linking structure, microhardness and adhesion were studied for ion-beam mixed tungsten layers deposited on the surface of high-speed steel. The 45 nm thick W layer were mixed with 340 keV Kr ions at temperatures ranging from RT up to 450 °C. The increase of mixing temperature results in partial crystallization of the layers and the increase of the layer hardness. Substantial increase of layer adhesion has been observed in scratch tests for all mixed samples. 相似文献
998.
DA Woolf KC Rose J Rumberg DI Westwood F Reinhardt SJ Morris W Richter RH Williams 《Canadian Metallurgical Quarterly》1995,51(7):4691-4694
999.
Birch J.R. Simonis G.J. Afsar M.N. Clarke R.N. Dutta J.M. Frost H.M. Gerbaux X. Hadni A. Hall W.F. Heidinger R. Ho W.W. Jones C.R. Koniger F. Moore R.L. Matsuo H. Nakano T. Richter W. Sakai K. Stead M.R. Stumper U. Vigil R.S. Wells T.B. 《Microwave Theory and Techniques》1994,42(6):956-965
The results of a measurement intercomparison aimed at assessing the systematic errors in near-millimetre-wavelength dielectric measurements on reasonably transparent solid specimens are presented and discussed. Various monochromatic, broad band, guided wave and free space measurement methods were intercompared in the frequency region from 30 to 900 GHz using round-robin measurements of the refractive index and absorption coefficient of seven specimens. Typically, systematic errors of up to 1% were found in the refractive index results, while very much larger systematic errors were found in the absorption results 相似文献
1000.
Produkte zum IT-gestützten Social Networking in Unternehmen 总被引:2,自引:2,他引:0
The use of Social Networking Services for private purposes has been increasing considerably in the past few years. In the same time companies started to experiment with such services to support formal and informal communication and networking among their employees. This article gives an overview of services and application for IT-supported Social Networking in companies. First, the authors place Social Networking Services in the context of Web 2.0 and Social Software. Thereupon, they discuss the benefits and the motivation of the deployment of Social Networking Software in companies, and introduce some specific IT solutions. Finally, they also address necessary future developments in the field of Social Networking Services. 相似文献