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1.
This study evaluated relations among optimism, perceived stress management skills (PSMS), and positive mood in 46 men who had surgical treatment for localized prostate cancer. The authors found that optimism, PSMS, and positive mood scores were positively correlated. Positive mood was unrelated to demographic and disease-related control variables. In a hierarchical regression model controlling for PSMS, the relationship between optimism and positive mood became nonsignificant, whereas PSMS remained a correlate of positive mood. Results suggest that the relationship between optimism and positive mood may be mediated by belief in being able to use stress management techniques effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Low-power wide-dynamic-range systems are extremely hard to build. The biological cochlea is one of the most awesome examples of such a system: It can sense sounds over 12 orders of magnitude in intensity, with an estimated power dissipation of only a few tens of microwatts. In this paper, we describe an analog electronic cochlea that processes sounds over 6 orders of magnitude in intensity, and that dissipates 0.5 mW. This 117-stage, 100 Hz to 10 KHz cochlea has the widest dynamic range of any artificial cochlea built to date. The wide dynamic range is attained through the use of a wide-linear-range transconductance amplifier, of a low-noise filter topology, of dynamic gain control (AGC) at each cochlear stage, and of an architecture that we refer to as overlapping cochlear cascades. The operation of the cochlea is made robust through the use of automatic offset-compensation circuitry. A BiCMOS circuit approach helps us to attain nearly scale-invariant behavior and good matching at all frequencies. The synthesis and analysis of our artificial cochlea yields insight into why the human cochlea uses an active traveling-wave mechanism to sense sounds, instead of using bandpass filters. The low power, wide dynamic range, and biological realism make our cochlea well suited as a front end for cochlear implants.  相似文献   
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ß-Crystallins are structural lens proteins with aconserved two-domain structure and variable N- and C-terminalextensions. These extensions are assumed to be involved in quaternaryinteractions within the ß-crystallin oligomers orwith other lens proteins. Therefore, the production of ßA3-and ßAl-crystallin from the single ßA3/A1mRNA by dual translation initiation is of interest. These crystallinsare identical, except that ßAl has a much shorterN-terminal extension than ßA3. This rare mechanismhas been conserved for over 250 million years during the evolutionof the ßA3/A1 gene, suggesting that the generationof different N-terminal extensions confers a selective advantage.We therefore compared the stability and association behaviourof recombinant ßA3- and ßAl-crystallin.Both proteins are equally stable in urea- and pH-induced denaturationexperiments. Gel filtration and analytical ultracentrifugationestablished that ßA3 and ßA1 both form homodimers.In the water-soluble proteins of bovine lens, ßA3and ßA1 are present in the same molecular weight fractions,indicating that they oligomerize equally with other ß-crystallins.1H-NMR spectroscopy showed that residues Met1 to Asn22 of theN-terminal extension of ßA3 have great flexibilityand are solvent exposed, excluding them from protein interactionsin the homodimer. These results indicate that the differentN-terminal extensions of ßA3 and ßA1 donot affect their homo- or heteromeric interactions.  相似文献   
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Computational science is increasingly supporting advances in scientific and engineering knowledge. The unique constraints of these types of projects result in a development process that differs from the process more traditional information technology projects use. This article reports the results of the sixth case study conducted under the support of the Darpa High Productivity Computing Systems Program. The case study aimed to investigate the technical challenges of code development in this environment, understand the use of development tools, and document the findings as concrete lessons learned for other developers' benefit. The project studied here is a major component of a weather forecasting system of systems. It includes complex behavior and interaction of several individual physical systems (such as the atmosphere and the ocean). This article describes the development of the code and presents important lessons learned.  相似文献   
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In considering well-being among survivors of life-threatening illnesses such as breast cancer, 2 important questions are whether there is continuity between initial adjustment and longer term adjustment and what role personality plays in long-term adjustment. In this research, a sample of 163 early stage breast cancer patients whose psychosocial adjustment was first assessed during the year after surgery completed the same measures 5-13 years after surgery. Initial reports of well-being were relatively strong predictors of follow-up well-being on the same measures. Initial optimism and marital status also predicted follow-up adjustment, even controlling for earlier adjustment, which exerted a substantial unique effect in multivariate analyses. In contrast, initial medical variables played virtually no predictive role. There is substantial continuity of subjective well-being across many years among survivors of breast cancer, rooted partly in personality and social connection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Cancer patients experience positive as well as adverse consequences from diagnosis and treatment. The study reported here examined longer term reverberations of such experiences. A set of benefit-finding items along with measures of well-being were completed by 230 early-stage breast cancer patients in the year postsurgery. Four to 7 years later, 96 of them again completed measures of well-being. Controlling for initial distress and depression, initial benefit finding in this sample predicted lower distress and depression at follow-up. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We present a method for selecting test sequences for concurrent programs from labeled transitions systems (LTS). A common approach to selecting test sequences from a set of LTSs is to derive a global LTS, called the reachability graph, and then force deterministic program executions according to paths selected from the graph. However, using a reachability graph for test path selection introduces a state explosion problem. To overcome this problem, a reduced graph can be generated using incremental reachability analysis, which consists of repeatedly generating a reachability graph for a subset of LTSs, reducing this graph, and using the reduced graph in place of the original LTSs. Unfortunately, existing incremental reachability analysis techniques generate reduced graphs with insufficient information for deterministic testing. We present an incremental approach to testing concurrent programs. Incremental testing consists of incremental reachability analysis for test path selection and deterministic testing for test execution. We define a new type of reachability graph for incremental analysis, called an annotated labeled transition system (ALTS). An ALTS is an LTS annotated with information necessary for deterministic testing. We propose practical coverage criteria for selecting tests paths from an ALTS and present an ALTS reduction algorithm. The results of several case studies are reported  相似文献   
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BACKGROUND: In January 1996, 38 hospitals and health care organizations (for a total of 40 hospitals) in the United States came together in an Institute for Healthcare Improvement (IHI; Boston) Breakthrough Series collaborative to reduce adverse drug events-injuries related to the use or nonuse of medications. METHODS: The participants were taught the Model for Improvement, a method for rapid-cycle change and evaluation, and were then coached on how to identify their own problem areas and develop changes in practice for rapid-cycle testing. These changes could be implementation of one or more known medication error prevention practices or new practices developed. RESULTS: During a 15-month period the 40 hospitals conducted a total of 739 tests of changes. Process changes accounted for 63% of the cycles; the remainder consisted of preliminary data gathering, consensus-building, or education cycles. Eight types of changes were implemented by seven or more hospitals, with a success rate of 70%. These changes included non-punitive reporting, ensuring documentation of allergy information, standardizing medication administration times, and implementing chemotherapy protocols. DISCUSSION: Success in making significant changes was associated with strong leadership, effective processes, and appropriate choice of intervention. Successful teams were able to define, clearly state, and relentlessly pursue their aims, and then chose practical interventions and moved early into changing a process. They did not spend months collecting data before beginning a change. Changes that were most successful were those that attempted to change processes, not people. Health care organizations committed to patient safety need not regard current performance limits as inevitable.  相似文献   
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