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71.
Reports an error in "Site matters: Multisite randomized trial of motivational enhancement therapy in community drug abuse clinics" by Samuel A. Ball, Steve Martino, Charla Nich, Tami L. Frankforter, Deborah Van Horn, Paul Crits-Christoph, George E. Woody, Jeanne L. Obert, Christiane Farentinos and Kathleen M. Carroll (Journal of Consulting and Clinical Psychology, 2007[Aug], Vol 75[4], 556-567). There are two errors in the means and standard deviations reported in Table 1 (p. 561). The mean (and standard deviation) for the Total sample % positive urine drug tests (28 days) in the motivational enhancement therapy (MET) column is not 0.21 (SD = 0.35) as reported, but rather 0.28 (SD = 0.40). The mean (and standard deviation) for the Total sample % positive urine drug tests (28 days) in the counseling as usual (CAU) column is not 0.28 (SD = 0.40) as reported, but rather 0.31 (SD = 0.41). These corrections do not change any of the values reported for the d, F, or p statistics in this table. (The following abstract of the original article appeared in record 2007-11558-005.) The effectiveness of motivational enhancement therapy (MET) in comparison with counseling as usual (CAU) for increasing retention and reducing substance use was evaluated in a multisite randomized clinical trial. Participants were 461 outpatients treated by 31 therapists within 1 of 5 outpatient substance abuse programs. There were no retention differences between the 2 brief intervention conditions. Although both 3-session interventions resulted in reductions in substance use during the 4-week therapy phase, MET resulted in sustained reductions during the subsequent 12 weeks whereas CAU was associated with significant increases in substance use over this follow-up period. This finding was complicated by program site main effects and higher level interactions. MET resulted in more sustained substance use reductions than CAU among primary alcohol users, but no difference was found for primary drug users. An independent evaluation of session audiotapes indicated that MET and CAU were highly and comparably discriminable across sites. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We have recently demonstrated, by employing azobenzene glycosides, that bacterial adhesion to surfaces can be switched through reversible reorientation of the carbohydrate ligands. To investigate this phenomenon further, we have turned here to more complex—that is, multivalent—azobenzene glycoclusters. We report on the synthesis of a photosensitive trivalent cluster mannoside conjugated to an azobenzene hinge at the focal point. Molecular dynamics studies suggested that this cluster mannoside, despite the conformational flexibility of the azobenzene-glycocluster linkage, offers the potential for reversibly changing the glycocluster's orientation on a surface. Next, the photoswitchable glycocluster was attached to human cells, and adhesion assays with type 1 fimbriated Escherichia coli bacteria were performed. They showed marked differences in bacterial adhesion, dependent on the light-induced reorientation of the glycocluster moiety. These results further underline the importance of orientational effects in carbohydrate recognition and likewise the value of photoswitchable glycoconjugates for their study.  相似文献   
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本文介绍了一种AccuWand研究工具。该工具采用一种新方法,无需裂解细胞或者降解样品便能在几秒钟内快速收集低浓度的细胞和核酸。并通过实例研究展示了该工具的应用价值。  相似文献   
76.
The interaction between a single molecule and the STM tip during intramolecular manipulation is investigated in detail. We show that the conformational change of complex organic molecules can be induced reversibly and very reliably by using exclusively attractive forces. By studying the dependence of this process on the bias voltage and the tip position, the driving forces are characterized. Different regimes of tip-molecule interactions are observed as a function of the distance.  相似文献   
77.
Film cooling is an important measure to enable an increase of the inlet temperature of a gas turbine and, thereby, to improve its overall efficiency. The coolant is ejected through spanwise rows of holes in the blades or endwalls to build up a film shielding the material. The holes often are inclined in the downstream direction and give rise to a kidney vortex. This is a counter-rotating vortex pair, with an upward flow direction between the two vortices, which tends to lift off the surface and to locally feed hot air towards the blade outside the pair. Reversing the rotational sense of the vortices reverses these two drawbacks into advantages. In the considered case, an anti-kidney vortex is generated using two subsequent rows of holes both inclined downstream and yawed spanwise with alternating angles. In a previous study, we performed large-eddy simulations (which focused on the fully turbulent boundary layer) of this anti-kidney vortex film-cooling and compared them to a corresponding physical experiment. The present work analyzes the simulated flow field in detail, beginning in the plenum (inside the blade or endwall) through the holes up to the mixture with the hot boundary layer. To identify the vortical structures found in the mean flow and in the instantaneous flow, we mostly use the λ 2 criterion and the line integral convolution (LIC) technique indicating sectional streamlines. The flow regions (coolant plenum, holes, and boundary layer) are studied subsequently and linked to each other. To track the anti-kidney vortex throughout the boundary layer, we propose two criteria which are based on vorticity and on LIC results. This enables us to associate the jet vortices with the cooling effectiveness at the wall, which is the key feature of film cooling.  相似文献   
78.
This paper presents the stochastic elastic modulus reduction method for system reliability analysis of spatial variance frames based on the perturbation stochastic finite element method (PSFEM) and the local average of a random field. The stochastic responses and reliability index of each element of a structural frame are characterized by the PSFEM and the first-order second-moment method, to properly handle the correlation structures and scale of fluctuation of random fields. A strategy of elastic modulus adjustment for the estimation of system reliability is developed to determine the range and magnitude of elastic modulus reduction, by taking the element reliability index as a governing parameter. The collapse mechanism and system reliability index of a stochastic framed structure are determined through iterative computations of the PSFEM. Compared with the failure mode approaches in traditional system reliability analysis, the proposed method avoids two major difficulties, namely the identification of significant failure modes and estimation of the joint probability of failure modes. The influences of the correlation structure and scale of fluctuation of the random field upon system reliability are investigated to demonstrate the accuracy and computational efficiency of the proposed methodology in system reliability analysis of spatial variance frames.  相似文献   
79.
Data from a community-based multicenter study of motivational enhancement therapy (MET) and counseling as usual (CAU) for outpatient substance users were used to examine questions about the role of the alliance in MET and CAU. Most (94%) of the sample met diagnostic criteria for abuse or dependence (primarily alcohol and/or cocaine). Sixteen therapists for CAU and 14 for MET participated. No reliable differences in patient ratings (n = 319) on the Helping Alliance Questionnaire–II (HAq-II) were evident for MET compared to CAU, but significant differences between therapists were found within each condition in mean patient-rated HAq-II scores. Overall, average levels of alliance were high. The between-therapists component of the alliance, but not the within-therapist component, was significantly associated with self-reported days of primary substance use during the follow-up period from Week 4 to Week 16 (Cohen’s d = 0 .39; n = 257). Therapists with either low or very high alliances had relatively poorer average outcomes (quadratic effect, d = 0.44). For therapists in both MET and CAU, increased use of MET fundamental techniques and MET advanced techniques during treatment sessions was associated with higher levels of alliance. Implications of the findings for conceptualization of the alliance and for training of therapists are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
Memorializes Kenneth S. Bowers, who is noted as one of the world's preeminent hypnosis researchers and an important contributor to personality and cognitive psychology. A very lucid and persuasive writer, Bowers published more than 50 journal articles, 20 book chapters, and 2 books. One of the books, Hypnosis for the Seriously Curious (1976), is still widely regarded as the best general introduction to hypnosis. Many of his research contributions involved the application of E. R. Hilgard's neodissociation theory of divided consciousness to the understanding of a wide range of hypnotic phenomena, including posthypnotic suggestions, hallucinations, analgesia, and amnesia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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