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61.
Beach Steven R. H.; Hurt Tera R.; Fincham Frank D.; Franklin Kameron J.; McNair Lily M.; Stanley Scott M. 《Canadian Metallurgical Quarterly》2011,3(3):201
We examined 393 African American married couples assigned to (a) a culturally sensitive version of a widely disseminated relationship enhancement program (CS-PREP); (b) a similar version of the same program that also included a focus on prayer (PFP condition); or (c) an information-only control condition in which couples received a self-help version of the same program. Husbands averaged 40.5 years of age and wives averaged 38.9 years. We found a significant interaction between intervention and time of assessment, reflecting group differences in linear trends for the three conditions, with the two intervention conditions performing better than the control condition, and PFP producing superior outcomes to CS-PREP only for wives at post and marginally better results at 12-month follow-up. Results support continued exploration of the adjunctive use of prayer in the context of relationship enhancement programs where appropriate to make them more culturally sensitive. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
62.
M Fujita K Yamanishi E Araie S Sasayama DP McKown D Franklin 《Canadian Metallurgical Quarterly》1994,9(6):292-299
It is now accepted that repetitive 2-min coronary occlusion can develop collateral vessels to the area perfused by the occluded coronary artery. However, which factors influence collateral development has yet to be fully elucidated. The goal of the present study was to identify the determinants of the rate of coronary collateral development in dogs undergoing repeated coronary occlusion. The study was conducted in 19 conscious dogs instrumented for measurements of a subendocardial segment length in the area perfused by the left circumflex coronary artery (LCCA), LCCA flow, and left ventricular pressure. An externally inflatable pneumatic occluder was placed around the LCCA. After the recovery from surgery, 2-min LCCA occlusions were conducted eight times daily. Following 141 +/- 61 (SD) LCCA occlusions (20 +/- 7 days), an LCCA occlusion produced no reduction in segment shortening and negligible reactive hyperemia. The total number of LCCA occlusions needed for adequate collateral development (the rate of collateralization) correlated well with the severity of myocardial ischemia during the first occlusion, which was determined mainly by the extent of postsurgical initial collateral circulation. On the other hand, the response to the ischemic stimulus in the later stage of collateral development was independent of the extent of development of the initial postsurgical collaterals. It is concluded that the overall rate of collateral development is slower in dogs with initially poorer collaterals; however, the response of each dog to the ischemic stimulus in the later stage of collateral development was similar among dogs regardless of the extent of the initial collaterals. 相似文献
63.
Built-in self-test (BIST) methods are examined, including the fault models and the test algorithms on which the BIST implementations are based. The notion of generic test architectures suitable for implementing a wide variety of test algorithms is introduced. A taxonomy for test architectures is provided and used to categorize BIST implementations, and important implementations are surveyed. It is demonstrated that BIST is a viable solution to the problem of testing large memories and that approaches based on test architectures rather than on test algorithms are more versatile and will likely predominate in the future 相似文献
64.
WA Franklin AF Gazdar J Haney II Wistuba FG La Rosa T Kennedy DM Ritchey YE Miller 《Canadian Metallurgical Quarterly》1997,100(8):2133-2137
Individuals with one aerodigestive tract malignancy have a high incidence of second primary aerodigestive tumors. The mechanism for this field effect has not been determined. We studied an individual with widespread dysplastic changes in the respiratory epithelium but no overt carcinoma. The entire tracheobronchial tree obtained at autopsy was embedded in paraffin, and bronchial epithelial cells were isolated by microdissection. DNA extracted from the microdissected cells was analyzed for point mutations in the p53 tumor suppressor gene. A single, identical point mutation consisting of a G:C to T:A transversion in codon 245 was identified in bronchial epithelium from 7 of 10 sites in both lungs. Epithelium at sites containing the p53 mutation was morphologically abnormal, exhibiting squamous metaplasia and mild to moderate atypia. No invasive tumor was found in the tracheobronchial tree or any other location. Cells from peripheral blood, kidney, liver, and lymph node exhibited no abnormality in the p53 gene. The widespread presence of a single somatic p53 point mutation in the bronchi of a smoker suggests that a single progenitor bronchial epithelial clone may expand to populate broad areas of the bronchial mucosa-a novel mechanism for field carcinogenesis in the respiratory epithelium that may be of importance in assessing individuals for risk of a second primary tumor as well as in devising effective strategies for chemoprevention of lung cancer. 相似文献
65.
Active control devices can be implemented on seismic structures to reduce structural response from earthquakes. Certain locations of the structure are advantageous for placement of the controllers in the sense that these locations effectively reduce structural response while using the minimum control effort. A method is proposed which uses an empirical procedure to find the optimal locations by maximizing an optimal locations index. The method takes into consideration the modal responses and earthquake spectra for two different earthquake records. The proposed method is compared to two methods; in the first method a control energy performance index is minimized; the second method uses a minimum response performance index as the criterion. The proposed method is found to agree with the two alternative methods and saves computation time. 相似文献
66.
Parallel simulated annealing using speculative computation 总被引:1,自引:0,他引:1
Witte E.E. Chamberlain R.D. Franklin M.A. 《Parallel and Distributed Systems, IEEE Transactions on》1991,2(4):483-494
A parallel simulated annealing algorithm that is problem-independent, maintains the serial decision sequence, and obtains speedup which can exceed log2P on P processors is discussed. The algorithm achieves parallelism by using the concurrency technique of speculative computation. Implementation of the parallel algorithm on a hypercube multiprocessor and application to a task assignment problem are described. The simulated annealing solutions are shown to be, on average, 28% better than the solutions produced by a random task assignment algorithm and 2% better than the solutions produced by a heuristic 相似文献
67.
68.
R. P. Tucker P. Henningsson S. L. Franklin D. Chen Y. Ventikos R. J. Bomphrey M. S. Thompson 《Journal of the Royal Society Interface》2014,11(97)
In vitro mechanotransduction studies, uncovering the basic science of the response of cells to mechanical forces, are essential for progress in tissue engineering and its clinical application. Many varying investigations have described a multitude of cell responses; however, as the precise nature and magnitude of the stresses applied are infrequently reported and rarely validated, the experiments are often not comparable, limiting research progress. This paper provides physical and biological validation of a widely available fluid stimulation device, a see-saw rocker, as an in vitro model for cyclic fluid shear stress mechanotransduction. This allows linkage between precisely characterized stimuli and cell monolayer response in a convenient six-well plate format. Models of one well were discretized and analysed extensively using computational fluid dynamics to generate convergent, stable and consistent predictions of the cyclic fluid velocity vectors at a rocking frequency of 0.5 Hz, accounting for the free surface. Validation was provided by comparison with flow velocities measured experimentally using particle image velocimetry. Qualitative flow behaviour was matched and quantitative analysis showed agreement at representative locations and time points. Maximum shear stress of 0.22 Pa was estimated near the well edge, and time-average shear stress ranged between 0.029 and 0.068 Pa. Human tenocytes stimulated using the system showed significant increases in collagen and GAG secretion at 2 and 7 day time points. This in vitro model for mechanotransduction provides a versatile, flexible and inexpensive method for the fluid shear stress impact on biological cells to be studied. 相似文献
69.
K.J. Weber V. Everett P.N.K. Deenapanray E. Franklin A.W. Blakers 《Solar Energy Materials & Solar Cells》2006,90(12):1741-1749
Ray tracing modeling has been used to calculate the performance of static concentrator modules with a geometric concentration ratio of 2 and incorporating very narrow (1–2 mm), long and bifacial cells. The modules utilize either a v-groove or a lambertian rear reflector. It is shown that the use of very narrow cells allows a performance improvement of 5% or more compared to structures incorporating wider cells, in the case of v-groove reflectors. The averaged yearly performance for both types of reflectors is found to be rather similar, with expected light collection in the range 82–86% of that of a module with 100% cell coverage. Experimental measurements on modules with lambertian reflectors are shown to be in good agreement with the results of modeling. 相似文献
70.
Steven E. Franklin 《Computers & Geosciences》1987,13(6)
The general system of geomorphometry is composed of elevation, derivatives of elevation at a point, and moments of the distribution of elevation over some area. All of the point measures in this system can be obtained by computer processing of a digital elevation model (DEM), and they can be used as input to the analysis and classification of terrain. A suite of FORTRAN programs implementing this system for dense grid DEMs has been designed and used in various operating environments. Attention has been given to the methods used in the approximation of terrain concepts such as slope and relief. An area of high relief in subarctic Canada is used to illustrate the discussion. 相似文献