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51.
Morgenstern Jon; Irwin Thomas W.; Wainberg Milton L.; Parsons Jeffrey T.; Muench Frederick; Bux Donald A. Jr.; Kahler Christopher W.; Marcus Susan; Schulz-Heik Jay 《Canadian Metallurgical Quarterly》2007,75(1):72
This study tested the efficacy of behavioral treatments for alcohol use disorders (AUD) among men who have sex with men (MSM) and who are at risk for HIV transmission. HIV-negative MSM with current AUD (N = 198) were recruited, offered treatment focused on reducing drinking and HIV risk, and followed during treatment and 12 months posttreatment. Participants (n = 89) accepted treatment and were randomized to either 4 sessions of motivational interviewing (MI) or 12 sessions of combined MI and coping skills training (MI + CBT). Other participants (n = 109) declined treatment but were followed, forming a non-help-seeking group (NHS). MI yielded significantly better drinking outcomes during the 12-week treatment period than MI + CBT, but posttreatment outcomes were equivalent. NHS participants significantly reduced their drinking as well. Service delivery and treatment research implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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53.
Jason B. K. Pang Marc O. Eberhard John F. Stanton 《Canadian Metallurgical Quarterly》2010,15(3):231-239
A new beam-to-column connection has been developed for assembling precast concrete bridge bents in regions of high seismicity. The connection is made with a small number of large column bars, which are grouted into large corrugated-metal ducts embedded in the cap beam. Bents built with these connections can be erected quickly and permit generous construction tolerances. To evaluate the seismic performance of the proposed connection, lateral-load tests were performed on three manifestations of the connection, as well as on a comparable cast-in-place connection. The tests demonstrated that the force-displacement response and damage progression in the precast connection are similar to those of typical cast-in-place concrete connections. Deliberate partial debonding of the longitudinal reinforcement only slightly affected the force-displacement response and observed damage. 相似文献
54.
Frank Wiesmann Jan Ruff Charlotte Dienesch Andrea Leupold Eberhard Rommel Axel Haase Stefan Neubauer 《Magma (New York, N.Y.)》2000,11(1):10-15
9. Conclusion Due to its high temporal and spatial resolution, magnetic resonance imaging meets the requirements for accurate and robust
in vivo visualization of the murine cardiovascular system. As an intrinsically three-dimensional imaging technique, it allows
for quantification of LV volumes without relying on geometric models. Therefore, MRI is uniquely suited for the investigation
of morphologic and functional changes in models of heart failure.
The potential application of MRI in the mouse comprises visualization of cardiovascular anatomy and pathology in newborn and
adult mice, detection of LV geometric and functional changes both acutely and chronically, visualization of cardiac microstructures
such as cardiac valves and coronary arteries, and characterization and quantification of arteriosclerotic plaques in major
murine arteries. Furthermore, MR spectroscopy applied to the mouse heart can give important information on in vivo myocardial
metabolism. Thus, we feel confident that high resolution MRI may substantially contribute to the understanding of the basic
mechanisms of a variety of cardiovascular diseases. 相似文献
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56.
Herbert Wilhelmi Eberhard Steinmetz Gereon Schlsser Ulrich Renz Bernd Hillemacher Frank Lange 《国际钢铁研究》1991,62(11):492-495
Zur Erfassung der Strömungsverhältnisse in Kaltmodellen bodengeblasener Stahlwerkspfannen wurden theoretische und experimentelle Untersuchungen durchgeführt. Frühere Berechnungen laminarer Strömungen, die unter stark vereinfachenden Annahmen vorgenommen wurden, zeigen nur tendenzielle Übereinstimmungen zu den mit LDA-Verfahren ermittelten Strömungsbildern. Durch die Entwicklung der Großrechneranlagen ist der Einsatz von Strömungssimulationsprogrammen möglich, mit denen auch turbulente Strömungen berechnet werden können. Der Vergleich der berechneten Geschwindigkeitsvektorfelder mit den gemessenen Vektorfeldern zeigt eine grundsätzlich übereinstimmende Darstellung der Strömungsverläufe. Jedoch werden die im Experiment an Wassermodellen beobachteten Gegenwirbel und Ablösungen der Abwärtsströmungen von der Gefäßwand rechnerisch nicht erfaßt. Nur die numerische Simulation für zähere Flüssigkeiten (Paraffinöl) zeigt eine von der Wand abgelöste Abwärtsströmung und die Ausbildung eines Gegenwirbels. Man kommt also nicht umhin, neben der mathematischen Modellierung auch praktische Versuche durchzuführen, wie man umgekehrt die physikalischen Modelle mit mathematischen begleiten sollte. 相似文献
58.
59.
Eberhard Seifert 《Progress in Nuclear Energy》1990,24(1-3):251-258
A monte Carlo method for the calculation of the reactivity effect of a small sample in a nuclear reactor is described. Particle histories are started within the sample. Therefore, it is not necessary to enter the sample from outside with a small probability. After leaving the sample, the histories are terminated at some distance from the sample site using pre-calculated results of the unperturbed reference system. The influence of some approximations is diminished because these pre-calculated results are used only far away from the region of interest. Some numerical results show the efficiency of the method. The method is fast and can also be used at rather small and slow computers. 相似文献
60.
Bartolomucci Alessandro; de Biurrun Gabriel; Fuchs Eberhard 《Canadian Metallurgical Quarterly》2001,115(4):344
This study investigated how male tree shrews (Tupaia balngeri) performed in a searching task while in their home cages and assessed whether different food distributions affected their performance. The animals were faced with a holeboard containing 9 food sources arranged in a 3 X 3 matrix or in 3 clusters, each containing 3 sources. Animals tended to start and end the trials from preferred locations, thereafter solving the task by strategically organizing the reward collection according to a minimum-distance principle. In the cluster configuration, they visited the sources hierarchically. Food distribution did not affect the performance. Comparison with data from mice and capuchin monkeys revealed that tree shrews and capuchins solved the task in a similar strategic way, whereas mice did not. These findings attract particular attention because of the phylogenetic position of tree shrews, which are regarded as closely related to primates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献