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41.
Traditionally, a database manager tracks only transactions — an insufficient way to maintain a complete history. This multilevel system tracks three history levels: character, transaction, and global action. 相似文献
42.
Kazdin Alan E.; Bass Debra; Ayers Wayne A.; Rodgers Antoinette 《Canadian Metallurgical Quarterly》1990,58(6):729
The present study evaluated the characteristics of research on child and adolescent psychotherapy. Published studies (N?=?223) of psychotherapy from 1970 to 1988 were codified to characterize research, clinical, and methodological characteristics. The major results indicate that (1) treatment research focuses almost exclusively on the impact of treatment techniques with scant attention to influences (child/adolescent, parent, family, therapist) that may moderate outcome and (2) several characteristics of the children/adolescents and methods of treatment delivery and approaches depart markedly from those evident in the practice of treatment. Priorities for treatment research to place clinical practice on firmer empirical footing are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
44.
This study was designed to draw on clinical practice as a way of identifying priority areas for child and adolescent psychotherapy research. 1,162 psychologists and psychiatrists described several features of their clinical work and evaluated the effects of alternative treatment approaches, factors that influence therapeutic change, and the priority of alternative types of research. The majority agreed on (a) the importance of several specific child, parent, and therapist factors that contribute to outcome; (b) the utility and effectiveness of alternative treatment approaches; and (c) the high priority of research on therapeutic processes and matching cases to alternative types of treatments. In general, the factors, treatments, and types of studies identified have rarely been examined empirically. The use of practitioner views to identify lines of research may aid not only in reducing the hiatus between research and practice but also in placing clinical work on a stronger empirical footing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
A relationship between instantaneous crack tip velocity (
), dynamic stress intensity factor (KI, and temperature (T) for A533B steel is estimated using dynamic crack position vs time data measured in a series of very large scale crack arrest tests. The corresponding dynamic stress intensity vs time history and the dynamic arrest toughness for each test are obtained from generation mode elastodynamic analyses based on cubic polynomial fits to the discrete crack position data points. Application mode elastodynamic analytical predictions based on the proposed
relationship are within 7% of experimentally measured arrest crack lengths and within 50% of measured arrest times. These predictions represent significant improvements over results obtained using previous preliminary estimates of the
relation for A533B. The influence of nonlinear material behavior on the results is also evaluated. 相似文献
46.
Under pressurized thermal shock (PTS) loading conditions arrest of running cracks at temperatures that range up to or above those corresponding to the onset of Charpy upper shelf is of particular interest. Only few crack arrest toughness (KIa) data above 200 MPa√m obtained from rather expensive PTS-experiments and wide-plate tests are available. In the present paper the capabilities of a relatively small panel crack arrest specimen for yielding KIa data in excess of 200 MPa√m under conditions of a rising KI-field are investigated. For this purpose static and dynamic finite element analyses are performed. It is shown that dynamic effects cannot be neglected for this specimen type and KIa-values up to about 300 MPa√m can be expected from measurements in suitably conducted experiments. 相似文献
47.
Bass Bernard M.; Avolio Bruce J.; Jung Dong I.; Berson Yair 《Canadian Metallurgical Quarterly》2003,88(2):207
How do leadership ratings collected from units operating under stable conditions predict subsequent performance of those units operating under high stress and uncertainty? To examine this question, the authors calculated the predictive relationships for the transformational and transactional leadership of 72 light infantry rifle platoon leaders for ratings of unit potency, cohesion, and performance for U.S. Army platoons participating in combat simulation exercises. Both transformational and transactional contingent reward leadership ratings of platoon leaders and sergeants positively predicted unit performance. The relationship of platoon leadership to performance was partially mediated through the unit's level of potency and cohesion. Implications, limitations, and future directions for leadership research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
R Zhang E Shohami E Beit-Yannai R Bass V Trembovler A Samuni 《Canadian Metallurgical Quarterly》1998,24(2):332-340
Reactive oxygen-derived species were previously implicated in mediation of post-traumatic brain damage; however, the efficacy of traditional antioxidants in preventing/reversing the damage is sometimes limited. The present work focused on the mechanisms underlying the neuroprotective activity of cell permeable, nontoxic, antioxidants, namely stable nitroxide radicals in an experimental model of rat closed-head injury. Brain damage was induced by the weight-drop method and the clinical status was evaluated according to a neurological severity score at 1 h and 24 h, where the difference between these scores reflects the extent of recovery. The metal chelator deferoxamine as well as three nitroxide derivatives, differing in hydrophilicity and charge, and one hydroxylamine (a reduced nitroxide) facilitated the clinical recovery and decreased the brain edema. The nitroxides, but neither the hydroxylamine nor deferoxamine, protected the integrity of the blood-brain barrier. Superoxide dismutase also improved the clinical recovery but did not affect brain edema or the blood-brain barrier. The results suggest that by switching back and forth between themselves, the nitroxide and hydroxylamine act catalytically as self-replenishing antioxidants, and protect brain tissue by terminating radical-chain reactions, oxidizing deleterious metal ions, and by removal of intracellular superoxide. 相似文献
49.
Celiac disease, or gluten-sensitive enteropathy, classically presents as diarrhea and weight loss in childhood, but it may also have protean manifestations and appear well into adult life. The increasing availability of noninvasive blood tests that are highly sensitive and specific for celiac disease enables primary care physicians to recognize the disorder in a wide variety of clinical situations. The authors believe that the disease is more common than supposed and thus offer this diagnostic review to increase awareness. 相似文献
50.
EA Gaumnitz P Bass MA Osinski MA Sweet C Singaram 《Canadian Metallurgical Quarterly》1995,109(3):789-799
BACKGROUND & AIMS: Achalasia is characterized by loss of myenteric neurons and incomplete relaxation of the lower esophageal sphincter (LES). The aim of this study was to develop an achalasia model in the opossum using the surfactant benzyldimethyltetradecylammonium chloride (BAC). This study further characterizes the achalasia model. METHODS: BAC or saline was injected circumferentially into the LES of 14 adult opossums. Eight months after injection, manometry, isolated muscle bath studies, electrical field stimulation, and histochemical analysis were performed. RESULTS: Manometrically, the LES of BAC-treated opossums showed higher pressures (38.7 +/- 12 mm Hg vs. 17 +/- 3.0 mm Hg) and reduced esophageal body contraction amplitudes (4.2 +/- 3 mm Hg vs. 27.4 +/- 12 mm Hg). Isolated muscle strips challenged with carbachol and sodium nitroprusside contracted and relaxed similarly to controls. Electrical field stimulation failed to induce relaxation in BAC-treated tissue but did induce contraction. Contractile responses were markedly reduced by tetrodotoxin and atropine in BAC-treated animals and controls. An altered nitric oxide system was shown by the lack of response to L-arginine and N omega-nitro-L-arginine. Histology showed loss of myenteric neurons and increased cholinergic nerve bundles. CONCLUSIONS: Loss of NO inhibitory myenteric neurons markedly reduces the relaxation of the LES, and histology and pharmacological responses suggest a proliferation of cholinergic nerves into the LES contributing to the static elevated pressures of the amyenteric LES. 相似文献