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1.
Cooper M. Lynne; Wood Phillip K.; Orcutt Holly K.; Albino Austin 《Canadian Metallurgical Quarterly》2003,84(2):390
Longitudinal data from a representative sample of 1,978 Black and White adolescents were used to examine the role of personality in multiple risk or problem behaviors. Results indicate that covariation among diverse behaviors (educational underachievement, delinquent behavior, substance use, sexual behavior) can be adequately modeled by a single higher order factor, and that impulsivity and avoidance coping serve as generalized risk factors for involvement in these behaviors. Whereas none of the personality variables examined explained change in problem behaviors once established, avoidance coping prospectively predicted involvement among a subgroup of adolescents with little or no prior involvement. Results suggest that dysfunctional styles of regulating emotions and emotionally driven behaviors are core features of risky or problem behaviors during adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The ability of rotorcraft to fly at low altitude is hindered by the high pilot workload required to avoid obstacles. The development of automation tools that can detect obstacles in the rotorcraft flight path, warn the crew, and interact with the guidance system to avoid detected obstacles would significantly reduce pilot workload and increase safety. This article describes an obstacle detection approach based on feature tracking and recursive range estimation that takes into account the characteristics of rotorcraft flight. The merits and weaknesses of the approach are discussed using image sequences from the laboratory and from flight. © 1992 John Wiley & Sons, Inc. 相似文献
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Ten areas of health knowledge were investigated in 2 studies, 1 of college students (N=169) and 1 of adults from the community (ages 19-70; N=176). Measures assessed knowledge of aging, orthopedic/ dermatological concerns, common illnesses, childhood/early life, serious illnesses, mental health, nutrition, reproduction, safety, and treatment of illness/disease. Significant gender differences favoring women were found for most areas of health knowledge, especially reproduction and early life. Results showed that cognitive ability accounted for the most variance in health knowledge with nonability (personality and interest traits) and demographic variables accounting for smaller but significant amounts of variance across most knowledge domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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David Lloyd Suzie Morrell Helle N. Carlsen Hans Degn Phillip E. James Christopher C. Rowlands 《Yeast (Chichester, England)》1993,9(8):825-833
Saccharomyces cerevisiae HSc was grown with ethanol at concentrations up to 10% (v/v). The immediate effects of additions of externally added ethanol on CO2 production and O2 consumption of washed organisms were studied by stopped-flow membrane inlet quadrupole mass spectrometry. Fermentative activities of organisms grown with ethanol (0–5% v/v) showed similar sensitivities to inhibition by ethanol, whereas those grown with 10% (v/v) ethanol had become protected and were markedly less sensitive. The fluidity of subcellular membrane fractions was measured by determination of the temperature dependence of the rotational order parameter of the spin label 5-doxyl stearic acid (free radical) by electron spin resonance. Mitochondria prepared from yeasts grown with 0, 7 and 9% (v/v) ethanol showed similar overall fluidity, although differences in temperature-dependent behaviour indicate altered lipid composition or lateral phase separations. On the other hand the microsomal fraction from organisms grown with 9% ethanol showed a remarkable increase in fluidity. These data suggest that the protective effects of growth with ethanol near the limit of tolerance on fermentative activities may arise from altered plasma membrane fluidity properties. 相似文献
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Andy Shar Phillip Glass Sung Hyun Park Daeha Joung 《Advanced functional materials》2023,33(5):2211079
3D printing of conductive elastomers is a promising route to personalized health monitoring applications due to its flexibility and biocompatibility. Here, a one-part, highly conductive, flexible, stretchable, 3D printable carbon nanotube (CNT)-silicone composite is developed and thoroughly characterized. The one-part nature of the inks: i) enables printing without prior mixing and cures under ambient conditions; ii) allows direct dispensing at ≈100 µm resolution printability on nonpolar and polar substrates; iii) forms both self-supporting and high-aspect-ratio structures, key aspects in additive biomanufacturing that eliminate the need for sacrificial layers; and iv) lends efficient, reproducible, and highly sensitive responses to various tensile and compressive stimuli. The high electrical and thermal conductivity of the CNT-silicone composite is further extended to facilitate use as a flexible and stretchable heating element, with applications in body temperature regulation, water distillation, and dual temperature sensing and Joule heating. Overall, the facile fabrication of this composite points to excellent synergy with direct ink writing and can be used to prepare patient-specific wearable electronics for motion detection and cardiac and respiratory monitoring devices and toward advanced personal health tracking and bionic skin applications. 相似文献
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The use of digital document management and processing is increasing. Traditional workflows of paper forms are being replaced by electronic workflows of digital documents. These workflows often require multiple signatures to be added to the documents for authorization and/or integrity. We describe examples of digital workflows that illustrate problems with digital signatures: i.e. the use of digital signatures across entire documents results in signatures that can be unnecessarily invalidated by subsequent modification of the document. We propose the use of fragment signatures, which reduce unnecessary invalidation of signatures and enable greater concurrency in workflows. Our approach is document‐centric and does not use a centralized database. We report on an implementation that allows fragment signatures over document fragments as well as the attachment (or embedding) of other documents. This allows collaborative or cooperative editing to occur on parts of a document without disturbing unrelated signatures. We describe the lessons learned from our deployments and offer further ways to embed such signatures into other document types. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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We present a new concurrency model for the Eiffel programming language. The model is motivated by describing a number of semantic
problems with the leading concurrency model for Eiffel, namely SCOOP. Our alternative model aims to preserve the existing
behaviour of sequential programs and libraries wherever possible. Comparison with the SCOOP model is made. The concurrency
aspects of the alternative model are presented in CSP along with a model of exceptions. The results show that while the new
model provides increased parallelism, this comes with the price of increased overhead due to lock management. 相似文献