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排序方式: 共有735条查询结果,搜索用时 31 毫秒
81.
By a strategy suggested by E. H. Uhlenhuth et al (1983), Diagnostic and Statistical Manual of Mental Disorders (DSM-III) referenced syndrome classifications were derived on the basis of the Hopkins Symptoms Checklist—42 scores of 1,131 elderly community residents. Overall syndrome prevalence rates were consistent with other epidemiologic data: 3.9% for depression, 1.0% for agoraphobia-panic, 2.6% for other phobia, and 6.9% for anxiety. Prevalence rates reflected expected sex differences and showed an age trend for other phobias. Considerable comorbidity among syndromes was observed. The association of the syndromes with patterns of psychosocial risk factors, prior diagnoses, and medication suggests that some but not all of the identified syndromes reflect clinically relevant classifications. If further developed, syndrome classifications based on self-report scales can provide inexpensive and clinically relevant measures of caseness. Required refinements of this approach are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Matt Kaufmann 《Journal of Automated Reasoning》1992,9(3):355-372
We describe an implementation of an extension to the Boyer-Moore Theorem Prover and logic that allows first-order quantification. The extension retains the capabilities of the Boyer-Moore system while allowing the increased flexibility in specification and proof that is provided by quantifiers. The idea is to Skolemize in an appropriate manner. We demonstrate the power of this approach by describing three successful proof-checking experiments using the system, each of which involves a theorem of set theory as translated into a first-order logic. We also demonstrate the soundness of our approach.This research was supported in part by ONR Contract N00014-88-C-0454. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the official policies, either expressed or implied, of Computational Logic, Inc., the Office of Naval Research or the U.S. Government. 相似文献
83.
Resnicow Ken; Davis-Hearn Marsha; Smith Matt; Baranowski Tom; Lin Lillian S.; Baranowski Janice; Doyle Colleen; Wang Dongqing Terry 《Canadian Metallurgical Quarterly》1997,16(3):272
Social-cognitive theory (SCT) was used to explain the fruit and vegetable intake of 1,398 3rd graders. SCT variables assessed included self-efficacy, outcome expectations, preferences, social norms, asking skills, and knowledge. Fruit and vegetable intake was assessed with 7-day records. Bivariate correlations with fruit and vegetable intake ranged from .17 for asking skills to .29 for fruit and vegetable preferences. In analyses controlling for school-level clustering, only preferences and positive outcome expectations remained significantly associated with fruit and vegetable intake, accounting for approximately 10%–11% of the variance. Limitations in the conceptualization, scope, and measurement of the variables assessed may have contributed to the weak associations observed. Models incorporating factors other than individual-level social-cognitive variables may be required to more fully explain children's dietary behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Genetic and environmental influences on self-reported parent-child relationships were examined in a sample of 824 individual male twins and their parents. Cross-sectional comparisons of twin similarity at ages 11 and 17 yrs were undertaken to identify developmental changes in the contribution of genetic and environmental factors to family relationships. Significant genetic influences were found on perceptions of parent-son conflict, regard, involvement, and overall support. Heritabilities were significantly higher in older twins, suggesting increased genetic influence with age. Age differences were present primarily in the father-son relationship. These results provide support for the proposal of S. Scarr and K. McCartney (1983) that the importance of active gene-environment correlations increases during adolescence. Older adolescents may have more choice and impact on the nature of the relationships they have with their parents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
We have shown that osteogenic protein-1 (OP-1) (bone morphogenetic protein-7) is responsible for the induction of nephrogenic mesenchyme during embryonic kidney development. Gene knock-out studies showed that OP-1 null mutant mice die of renal failure within the first day of postnatal life. In the present study, we evaluated the effect of recombinant human OP-1 for the treatment of acute renal failure after 60 min bilateral renal artery occlusion in rats. Bioavailability studies in normal rats indicate that approximately 1.4 microg OP-1/ml is available in the circulation 1 min after intravenous administration of 250 microg/kg, which then declines steadily with a half life of 30 min. About 0.5% of the administered OP-1 dose/g tissue is targeted for OP-1 receptors in the kidney. We show that OP-1 preserves kidney function, as determined by reduced blood urea nitrogen and serum creatinine, and increased survival rate when administered 10 min before or 1 or 16 h after ischemia, and then at 24-h intervals up to 72 h after reperfusion. Histochemical and molecular analyses demonstrate that OP-1: (a) minimizes infarction and cell necrosis, and decreases the number of plugged tubules; (b) suppresses inflammation by downregulating the expression of intercellular adhesive molecule, and prevents the accumulation and activity of neutrophils; (c) maintains the expression of the vascular smooth muscle cell phenotype in pericellular capillaries; and (d) reduces programmed cell death during the recovery. Collectively, these data suggest that OP-1 prevents the loss of kidney function associated with ischemic injury and may provide a basis for the treatment of acute renal failure. 相似文献
86.
The impact of perceived group success-failure on motivational beliefs and attitudes: A causal model.
Two models describing the theoretical relationship among the constructs of perceived group success–failure, individual and collective levels of job-specific efficacy and outcome expectancy, satisfaction, and organizational commitment were developed. Model 1 proposed that the causal relationship between group success–failure and subsequent attitudinal variables (satisfaction and organizational commitment) is completely mediated by efficacy and outcome expectancy variables. Model 2 proposed a direct causal link from perceived group success–failure to the attitudinal variables and omitted questionable causal paths from personal efficacy and collective outcome expectancy to the attitudinal variables. The competing models were subjected to structural equation path model analysis. The 2nd model produced an adequate fit between theory and data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Matt Jones Steve Jones Gareth Bradley Nigel Warren David Bainbridge Geoff Holmes 《Personal and Ubiquitous Computing》2008,12(7):513-525
Listening to music on personal, digital devices whilst mobile is an enjoyable, everyday activity. We explore a scheme for
exploiting this practice to immerse listeners in navigation cues. Our prototype, ONTRACK, continuously adapts audio, modifying
the spatial balance and volume to lead listeners to their target destination. First we report on an initial lab-based evaluation
that demonstrated the approach’s efficacy: users were able to complete tasks within a reasonable time and their subjective
feedback was positive. Encouraged by these results we constructed a handheld prototype. Here, we discuss this implementation
and the results of field-trials. These indicate that even with a low-fidelity realisation of the concept, users can quite
effectively navigate complicated routes.
相似文献
Matt Jones (Corresponding author)Email: |
Steve JonesEmail: |
Gareth BradleyEmail: |
Nigel WarrenEmail: |
David BainbridgeEmail: |
Geoff HolmesEmail: |
88.
Park JU Hardy M Kang SJ Barton K Adair K Mukhopadhyay DK Lee CY Strano MS Alleyne AG Georgiadis JG Ferreira PM Rogers JA 《Nature materials》2007,6(10):782-789
Efforts to adapt and extend graphic arts printing techniques for demanding device applications in electronics, biotechnology and microelectromechanical systems have grown rapidly in recent years. Here, we describe the use of electrohydrodynamically induced fluid flows through fine microcapillary nozzles for jet printing of patterns and functional devices with submicrometre resolution. Key aspects of the physics of this approach, which has some features in common with related but comparatively low-resolution techniques for graphic arts, are revealed through direct high-speed imaging of the droplet formation processes. Printing of complex patterns of inks, ranging from insulating and conducting polymers, to solution suspensions of silicon nanoparticles and rods, to single-walled carbon nanotubes, using integrated computer-controlled printer systems illustrates some of the capabilities. High-resolution printed metal interconnects, electrodes and probing pads for representative circuit patterns and functional transistors with critical dimensions as small as 1 mum demonstrate potential applications in printed electronics. 相似文献
89.
ManyEyes: a site for visualization at internet scale 总被引:1,自引:0,他引:1
Viegas FB Wattenberg M van Ham F Kriss J McKeon M 《IEEE transactions on visualization and computer graphics》2007,13(6):1121-1128
We describe the design and deployment of Many Eyes, a public web site where users may upload data, create interactive visualizations, and carry on discussions. The goal of the site is to support collaboration around visualizations at a large scale by fostering a social style of data analysis in which visualizations not only serve as a discovery tool for individuals but also as a medium to spur discussion among users. To support this goal, the site includes novel mechanisms for end-user creation of visualizations and asynchronous collaboration around those visualizations. In addition to describing these technologies, we provide a preliminary report on the activity of our users. 相似文献
90.
Used behavior genetic methods to investigate individual differences in memory performance. Memory and various cognitive and lifestyle variables were obtained from 93 monozygotic twin pairs and 67 dyzygotic twin pairs (aged 60–88 yrs) as part of the Minnesota Twin Study of Adult Development and Aging. Univariate analysis, used to determine the relative influence of genetic and environmental factors on 4 measures of memory (word recall, immediate and delayed text recall, and figure memory), suggested that 55% of the variance in memory performance could be attributed to genetic factors. Bivariate analysis was used to determine the specific variables that mediate the genetic and environmental influences on memory. Results suggested that the relationship between memory and cognitive variables was genetic in nature, whereas the nature of the relationship between memory and lifestyle variables was environmental. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献