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51.
52.
Writing and debugging concurrent (shared-variable) programs is notoriously difficult. This motivated the development of numerous static analysis and run-time analysis techniques designed to (help) ensure that concurrent programs satisfy common correctness requirements for concurrent programs, such as absence of race conditions and absence of deadlocks. This paper focuses on another common correctness requirement for concurrent programs, namely, atomicity, which requires that any set of concurrent invocations of designated procedures is equivalent to performing those invocations serially in some order. Run-time analysis algorithms for detecting violations of atomicity are presented. The algorithms vary in cost and precision. 相似文献
53.
Nalavany Blace A.; Ryan Scott D.; Gomory Tomi; Lacasse Jeffrey R. 《Canadian Metallurgical Quarterly》2005,14(1):27
In this pilot study, concept mapping, a methodological approach combining qualitative and quantitative analytic strategies, was used to identify the therapist qualities, competencies, and skills necessary for effective play therapy outcomes as perceived by a sub-sample of 28 experienced play therapists who are members of the Association for Play Therapy (APT). The clusters associated with the therapeutic relationship and facilitative skills (e.g., empathy, warmth, and genuineness) were rated as the most essential skills to possess and also as the most difficult to develop. In contrast, the clusters associated with play therapy interventions and theories were rated as the least important skills to possess but as the easiest to acquire. The findings are discussed, with implications for therapeutic practice, research, and policy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
Tony C. Scott Robert Mann Roberto E. Martinez II 《Applicable Algebra in Engineering, Communication and Computing》2006,17(1):41-47
We present a canonical form for a natural and necessary generalization of the Lambert W function, natural in that it requires minimal mathematical definitions for this generalization, and necessary in that it provides a means of expressing solutions to a number of physical problems of fundamental nature. This generalization expresses the exact solutions for general-relativistic self-gravitating N-body systems in one spatial and one time dimension, and a previously unknown mathematical link between the (1+1) gravity problem and the Schrödinger wave equation. 相似文献
55.
The temperature dependence observed in the mid- and near-infrared optical properties of YBa2Cu3O7 is explained in terms of the Drude model for free charge carriers. In the Drude model, the linear temperature dependence of the dc resistivity arises from the free charge carriers having a temperature-dependent mean free path. This temperature dependence results in the plasmon contribution to the dielectric constant having a damping coefficient which also varies linearly with temperature. We find that the temperature dependence which is observed in the absorption and reflection spectra of YBa2Cu3O7 is consistent with this simple model. 相似文献
56.
J. F. Scott 《Ferroelectrics Letters Section》1995,19(5):171-180
Mathematical analogies are developed between the formalism used to describe regenerative pulsations accompanying optical bistability in ferroelectrics and that used to parametrize the transition from steady flow to laminar vortex generation in viscous fluids. An “effective Reynolds number” and an “effective specific viscosity” are both defined for the optical bistability model. The characteristic length in the problem is defined in a way similar to that in Abrikosov's theory of Type II superconductors. 相似文献
57.
A Mitchener DJ Wyper J Patterson DM Hadley JT Wilson LC Scott M Jones GM Teasdale 《Canadian Metallurgical Quarterly》1997,62(6):633-636
We report a case of cervicofacial necrotizing fasciitis that developed after blepharoplasty, an occurrence that, to our knowledge, has not previously been reported in the medical literature. A patient who presented to our institution 3 days after undergoing blepharoplasty of the upper eyelid was diagnosed as having fulminant fasciitis involving extensive areas of the face, scalp, and neck. We review the case in detail and discuss clinical and radiological clues to diagnosis, surgical and medical management, wound care, and subsequent scar contracture. This case emphasizes the need for individualized, appropriate postoperative care and for an awareness of this rare, potentially fatal complication. Early recognition and aggressive treatment of cervicofacial fasciitis can arrest its rapid progression and prevent devastating sequelae. 相似文献
58.
Intravenous microdialysis sampling in the awake, freely-moving rat for the determination of free drug concentrations in blood is described. Intravenous microdialysis was performed with a nonmetallic, flexible dialysis probe. The pharmacokinetics of theophylline were determined using both microdialysis sampling and collection of whole blood following an iv dose. There was no difference in the half-life of elimination of theophylline determined by microdialysis, 4.4 +/- 0.4 h, and whole blood sampling, 4.5 +/- 0.7 h. The kinetics of elimination were affected by removing blood samples and by using anesthesia. The half-life of elimination was 4.4 +/- 0.4 h when using simultaneous microdialysis and whole-blood sampling and only 3.0 +/- 0.4 h using microdialysis alone. The half-life of elimination was 17.0 +/- 7.1 h in chloral hydrate anesthesized rats. Microdialysis samples were continuously collected for over 7 h without fluid loss using a single experimental animal. Microdialysis sampling directly assesses the free drug concentration in blood. The extent of theophylline binding to blood proteins was determined in vitro in rat plasma and rat whole blood using both ultrafiltration and microdialysis. Theophylline was (47.3 +/- 1.3)% bound in rat plasma and (52.2 +/- 1.6)% bound in rat whole blood. Microdialysis sampling is a powerful tool for pharmacokinetic studies, providing accurate and precise pharmacokinetic data. 相似文献
59.
MD Medlock JR Madsen PD Barnes DS Anthony LE Cohen RM Scott 《Canadian Metallurgical Quarterly》1997,27(3):121-128
There are many in vivo animal models for studying airway mucus secretion and hypersecretion, each with advantages and disadvantages. Use of a particular test system will depend upon the aspect of secretion to be modelled. Airway hypersecretory diseases exhibit chronic mucus hypersecretion, of which the clinical impact is predominantly in the distal airways. The majority of documented test preparations study acute secretion, invariably using tracheal preparations, but have been invaluable in elucidating the normal physiology of airway mucus secretion. Chronic models of the hypersecretory state in the distal airways have been developed, but are predominantly histologic in nature (for example quantification of increased goblet cell number). There are few investigations of mucus hypersecretion. Examination of the 'antisecretory' potential of pharmaceutical compounds has been investigated predominantly in chronic histologic models with the drug being given 'prophylactically' rather than 'therapeutically'. Refinement of chronic hypersecretory models should lead to elucidation of the connection between airway irritation, inflammation, MUC gene expression, mucous cell hyperplasia/metaplasia, airway hypersecretion and bronchial hypersecretory disease. 相似文献
60.