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11.
The validity and reliability of two factor structures of the Mental Adjustment to Cancer (MAC) scale for assessing coping style was assessed by examining the relationship between the subscales, psychological distress, and quality of life (QOL) among Stage II and Stage IV breast cancer patients in four phases. First, MANOVAs assessed differences in coping, distress, and QOL across disease stages. Second, for each MAC factor structure, canonical correlation analyses assessed the relationship between coping styles, distress, and QOL, for each disease-stage group separately. Third, structural equation modeling (SEM) assessed the relationship among coping styles, distress, and QOL for all participants. Finally, the internal consistency of both MAC factor structures was assessed using Chronbach's alpha. The results were as follows: (1) significant differences across disease stages were found for coping styles using either the Watson or the Schwartz MAC subscales, but there were no differences in levels of distress or QOL; (2) for both MAC factor structures, coping style was found to be highly related to emotional distress and QOL, however, the strengths of the correlations between individual coping styles and distress/QOL indicators varied across disease stages; (3) SEM indicated that coping style was significantly related to distress and QOL when stage of disease was not considered, and that coping style and indicators of distress/QOL are separate, but highly correlated factors, as opposed to a single latent construct; and, (4) the Watson MAC subscales showed slightly better internal consistency than the Schwartz MAC subscales. Taken together, these findings highlight: (i) the validity of both MAC factor structures for clinical and research use with American breast cancer patients; (ii) the role of coping style as a mediator between disease stage and psychological distress and QOL; and, (iii) the need for refinement of certain Watson and Schwartz subscales. 相似文献
12.
GJ Harris EH Aylward CE Peyser GD Pearlson J Brandt JV Roberts-Twillie PE Barta SE Folstein 《Canadian Metallurgical Quarterly》1996,53(4):316-324
During oogenesis in Drosophila, germ cells appear in sequential clusters of 16 interconnected cells. The events surrounding the differentiation of these cells are not fully understood. Here we present genetic and morphological analysis of mutations in the gene stand still (stil). Through complementation analyses we have refined the location of this gene to cyological region 49B-C. Our analyses of ovaries from ethylmethane sulfonate (EMS)-induced mutant alleles of this gene suggest that mutations in the stil gene produce a wide range of phenotypic abnormalities, from the absence of germ cells in the most severe alleles, to egg chambers with cytoskeletal defects in the less severe alleles. Our results suggest a role for this gene in specifying or maintaining a cytoskeletal component, with consequences during oogenesis and possibly during germ line sex determination. 相似文献
13.
In this paper, the concept of Human-Centred Technology will be described with regard to the different dimensions of workplace, groupwork and networks and in terms of the frameworks of both society and the natural environment. These different aspects of Human-Centred Systems will be illustrated by a series of case studies representing several European countries. The report covers a wide range of research fields. The emphasis is on technology: the roles of control and information technology in enterprises today — including issues of applying AI — and the strategies of designing and implementing technology taking into account the specific aspects which characterize human-centred systems. 相似文献
14.
By the very nature of information technology (IT), change and dynamism have always been significant drivers on its path to further development—and it has traditionally been the Western countries leading these. Now the picture is changing. The new high growth economies of the world (also known as BRIC countries) are increasingly pressing forward as active IT development drivers. Internal IT organizations of international companies are experiencing these global shifts firsthand and are facing changes in their traditional roles. This exploratory research is aimed at clarifying the context of the impact of high growth economies on such IT departments of Western-rooted enterprises. Forty-six interviews were conducted with IT managers, HR managers and expatriates emphasizing the importance of intercultural interaction, maturing IT economies, change in IT landscape and entrepreneurship. 相似文献
15.
Duyao Zhang Shoujin Sun Dong Qiu Mark A. Gibson Matthew S. Dargusch Milan Brandt Ma Qian Mark Easton 《Advanced Engineering Materials》2018,20(5)
16.
This paper reports on a method for the investigation of mechanical stress on MEMS sensor and actuator structures due to packaging
processes. A silicon test chip is developed and manufactured to validate the simulation results. Finite element analysis (FEA)
is used to optimize the geometric parameters and to find a stress sensitive sensor geometry. A diaphragm structure is used
as mechanical amplifier for bulk induced stresses during the packaging process. Piezo resistive solid state resistors are
doped into the surface of the chip to measure the stress in the diaphragms and at the contact pads being most significant
locations for analysis. A high precision ohmmeter was used to measure the resistance prior and past the packaging process.
The captured data allows for computation of the resulting stress loads in magnitude. Therefore, a stress evaluation of different
packaging technologies is conducted and the impact of the packaging process on reliability can be estimated immediately. 相似文献
17.
Lachter Joel Brandt Summer L. Battiste Vernol Matessa Michael Johnson Walter W. 《Cognition, Technology & Work》2017,19(2-3):279-288
Cognition, Technology & Work - From the 1950s through the 1980s, aircraft design was marked by an increase in reliability and automation, and, correspondingly, a decrease in the crew complement... 相似文献
18.
E. H. Brandt 《Journal of Low Temperature Physics》1981,44(1-2):33-57
The vortex lattice in type II superconductors is unstable against the growth of helical perturbations if the current along the vortices exceeds a critical value. The longitudinal critical current, the pitch, and the spatially varying amplitude of the elliptically polarized helices are calculated from the London theory at the onset of instability in planar current distributions far from the surface. For weak pinning (L2 c
66) the wavelength and width of the mode extend over the entire specimen, and the critical current is 2H(c
66/c
11)1/4. For moderate pinning (c
66 L2 c
11) the wavelength and width are close to Campbell's pinning length (c
11/L)1/2, and the critical current times its mean density is 2H
2(L/c
11)1/2. For strong pinning (L2 c
11) helical instability occurs at pin-free vortex sections, the helix wavelength is 2.2d, and the critical current density is 0.47Hd/2 (H, d, c
11 and c
66), and L are the magnetic field, spacing, elastic moduli, and pinning parameter of the vortex lattice, and is the magnetic penetration depth). 相似文献
19.
O'Brien S Luo Y Wu C Petrak M Bohm E Brandt JM 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2012,226(3):235-245
The micromotion at the interface between the polyethylene tibial insert and metal tibial tray [corrected] in modular total knee replacements [corrected] has been shown to contribute to wear particle-induced osteolysis and may [corrected] cause implant failure. Therefore, studying the design parameters that are involved in the backside wear process is an important task that may lead to improvement in new total knee replacements. In the present study, a finite element model was developed to predict the backside micromotion along the entire modular interface. Both the linear elastic constitutive model and non-linear J2-plasticity constitutive model were considered in the finite element model for polyethylene and were corroborated against published results obtained from displacement controlled knee simulator wear tests. The finite element simulation with the non-linear J2-plasticity constitutive model was able to predict backside micromotion [corrected] more accurately than the simulation with the linear elastic constitutive model. [corrected] The developed finite element model (including the non-linear J2-plasticity constitutive model) was then applied to assess the effects of the tibial tray locking mechanism design (dovetails versus fullperipheral [corrected] design) and different levels of interference fit on insert micromotion. The developed finite element model, implementing the non-linear J2-plasticity constitutive model, was shown to successfully predict clinical amounts of backside micromotion and could be used for the design and development of total knee replacements for the reduction of backside micromotion and polyethylene [corrected] wear. 相似文献
20.
Experimental evidence for flux-line cutting in superconductors (intersection and cross-joining of singly quantized vortices) is briefly reviewed. The interaction energy between two straight vortices tilted at an angle ( 0)is then shown to be finite in the London model, i.e., in the limit of vanishing core radius. Next, the activation energy and maximum interaction force are calculated for the vortices in an analytic approximation to the Ginzburg-Landau theory. Here two competing interactions determine the behavior. Electromagnetic repulsion (0 < < /2) varies as cos and decays over distances scaled by the penetration depth , while core attraction is independent of and varies over distances scaled by the coherence length . The force is always repulsive at large flux-line separation (0 < < /2) and its maximum decreases rapidly as decreases, so that flux-line cutting isexpected to be more probable in low- materials. The calculations provide a basis for explaining longitudinal flux-flow resistance as well as some intriguing magnetization behavior in the same configuration.This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Sciences Division, and by the Deutsche Forschungsgemeinschaft.On leave from Max-Planck-Institut für Metallforschung, Institut für Physik, Stuttgart, West Germany.On leave from New University of Ulster, Coleraine, Northern Ireland. 相似文献