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91.
Once merely thought of as the protein responsible for the overall physical nature of the human immunodeficiency virus type 1 (HIV-1), the Gag polyprotein has since been elucidated to have several roles in viral replication and functionality. Over the years, extensive research into the polyproteins’ structure has revealed that Gag can mediate its own trafficking to the plasma membrane, it can interact with several host factors and can even aid in viral genome packaging. Not surprisingly, Gag has also been associated with HIV-1 drug resistance and even treatment failure. Therefore, this review provides an extensive overview of the structural and functional roles of the HIV-1 Gag domains in virion integrity, functionality and infectivity.  相似文献   
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We argue that more help does not necessarily lead to more gratitude. Rather, gratitude depends on how a given instance of help compares with the help that a person is used to receiving. Participants read vignettes detailing an event in which 11 different friends either lent them varying amounts of money or spent varying amounts of time providing help. The amount of gratitude elicited by a given amount of help (e.g., a loan of £36 [about $56] or 49 min help) differed substantially depending on how this amount ranked among the help they were getting from their other friends. Comparison across four experimental conditions suggested that these judgments operated via the same general cognitive mechanisms used to judge other social events and psychophysical stimuli (as outlined by range frequency theory). Although more help does lead to more gratitude, people appear to be sensitive to how that help compares with what others are providing, and experienced gratitude depends on these relative judgments. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
94.
The recent article in Canadian Psychology by Carleton, Peluso, and Asmundson (2010) assessing the research activity of Canadian psychology departments with graduate programmes has generated substantial feedback. We are very pleased to have provided not only an initial data set for review by departments and individuals, but also to have prompted what we believe is an important discussion. The current article responds to a thoughtful critique and extension of our initial work (Symons, 2011). Herein we address and expand on each of the comments raised by Symons in an attempt to fully delineate the successes and challenges for our profession as we take the next steps in this area of research. Also, in light of the review and other anecdotal feedback received to date, we make further recommendations for using the data available from the Web of Knowledge, the rankings we provided, and the data provided by Symons. We conclude with directions for future research that we believe will help further the area. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
95.
A mind-body skills group program was evaluated to determine its effects on symptoms of posttraumatic stress disorder (PTSD) and depression, and on hopelessness in children and adolescents in Gaza. The 10-session mind-body skills groups included meditation, guided imagery, breathing techniques, autogenic training, biofeedback, genograms, and self-expression through words, drawings, and movement. Data were analyzed from 129 children and adolescents meeting criteria for PTSD. Significant improvements in PTSD and depression symptoms and a significant decrease in a sense of hopelessness were observed immediately following participation in the program. At 7-month follow-up, the improvements in the total PTSD and depression scores were largely maintained and the decreased sense of hopelessness was fully maintained despite ongoing violent conflict and economic hardship. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
96.
In vivo host responses to an electrode‐like array of aligned carbon nanotubes (ACNTs) embedded within a biopolymer sheet are reported. This biocompatibility study assesses the suitability of immobilized carbon nanotubes for bionic devices. Inflammatory responses and foreign‐body histiocytic reactions are not substantially elevated when compared to negative controls following 12 weeks implantation. A fibrous capsule isolates the implanted ACNTs from the surrounding muscle tissue. Filamentous nanotube fragments are engulfed by macrophages, and globular debris is incorporated into the fibrous capsule with no further reaction. Scattered leukocytes are observed, adherent to the ACNT surface. These data indicate that there is a minimal local foreign‐body response to immobilized ACNTs, that detached fragments are phagocytosed into an inert material, and that ACNTs do not attract high levels of surface fouling. Collectively, these results suggest that immobilized nanotube structures should be considered for further investigation as bionic components.  相似文献   
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We consider the amount of available information about an arbitrary future state of a Gaussian stochastic process. We derive an infinite series for the marginal mutual information in terms of the autocorrelation function. We derive an infinite series for the newly available information for prediction, the conditional mutual information, in terms of the moving average parameters, and directly characterize predictability in terms of sensitivity to random shocks. We apply our results to long memory, or more generally, hyperbolic decay models, and give information‐theoretic characterizations of the transition from persistence to anti‐persistence, stationary long memory to nonstationarity, and a stationary regime where the mutual information is not summable.  相似文献   
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JOM - The use of titanium machine turnings has been identified as a possible ultralow-cost method to produce titanium powder. However, very little data are available on the viability of this...  相似文献   
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