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排序方式: 共有410条查询结果,搜索用时 31 毫秒
31.
Osinsky Roman; Reuter Martin; Küpper Yvonne; Schmitz Anja; Kozyra Eva; Alexander Nina; Hennig Jürgen 《Canadian Metallurgical Quarterly》2008,8(4):584
The 5-HTTLPR is an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene. Prior research has revealed associations between the short-allele variant of this polymorphism, enhanced self-reported negative emotionality, and hypersensitivity of fear relevant neural circuits. In a sample of 50 healthy women we examined the role of 5-HTTLPR for cognitive-affective processing of phylogenetical fear-relevant stimuli (spiders) in a dot probe task. In contrast to homozygote long-allele carriers (ll), participants carrying at least 1 short allele (ss and sl) selectively shifted attention toward pictures of spiders, when these were presented for a duration of 2,000 ms. These results argue for an involvement of 5-HTTLPR in cognitive processing of threatening stimuli and thus, underpin its general role for individual differences in negative affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Ulrike Assmann Andreas Szentivanyi Yvonne Stark Thomas Scheper Silke Berski Gerald Dräger Robert H. Schuster 《Journal of materials science. Materials in medicine》2010,21(7):2115-2124
Fiber scaffolds of bioactive polysialic acid have been prepared via electrospinning for peripheral nerve regeneration. The
diameter, morphology and alignment of fibers in scaffolds were adjusted by variation of electrospinning parameters, which
are decisive for the cell-scaffold interaction. Due to the high water solubility of polysialic acid (poly-α-2,8-N-acetylneuraminic acid) a photoactive derivative (poly-α-2,8-N-pentenoylneuraminic acid) was used to obtain stable fiber scaffolds in water by photochemical crosslinking. At the optimized
fiber scaffolds good cell viability and directed cell proliferation along the fibers was achieved by cell tests with immortalized
Schwann cells. 相似文献
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In recent years competitive pressure in mobile markets has increased remarkably. New business models and thus new actors have entered the market. This contribution analyzes the reconfiguration of value structures and strategies in mobile markets. For this purpose, mobile network operators?? service portfolio is analyzed on the basis of a worldwide survey, and the relevant current and future value creation activities are identified with consideration of additional actors and influence factors. On that basis, roles are developed, linked with regard to value flows and combined to a reference model for the mobile market value net. Subsequently, scenario planning is used to develop a set of criteria for the construction of corresponding future scenarios and the application of the reference model is demonstrated with such a scenario. 相似文献
36.
A New In Situ Microscopy Approach to Study the Degradation and Failure Mechanisms of Time‐Dependent Dielectric Breakdown: Set‐Up and Opportunities
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Zhongquan Liao Martin Gall Kong Boon Yeap Christoph Sander Oliver Aubel Uwe Mühle Jürgen Gluch Sven Niese Yvonne Standke Rüdiger Rosenkranz Markus Löffler Norman Vogel Armand Beyer Hans‐Jürgen Engelmann Peter Guttmann Gerd Schneider Ehrenfried Zschech 《Advanced Engineering Materials》2014,16(5):486-493
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This article develops a conceptual framework to assist in determining the value to be gained from long-term international
assignments. 相似文献
38.
Cunningham CE Bruce BS Snowdon AW Chen Y Kolga C Piotrowski C Warda L Correale H Clark E Barwick M 《Accident; analysis and prevention》2011,43(6):1999-2009
Automobile crashes are the leading cause of death in children aged 1–14 years. Many children, however, are not properly restrained in safety seats that reduce serious injury and death. This study used a discrete choice conjoint experiment to study factors influencing the decision to use booster seats. Parents of 1714 children aged 4–9 years from nine Canadian provinces completed choice tasks presenting experimentally varied combinations of 15 4-level booster seat promotion attributes. Latent class analysis yielded three segments of parents. The choices of the Benefit Sensitive segment (50%) were most sensitive to the injury prevention benefits of booster seats. The choices of parents in the Context Sensitive segment (33.5%) were more likely to be influenced by installation complexity, oppositional behavior, and the prospect that their child may be teased for riding in booster seats. Parents in the High Risk segment (16.5%) were younger, less educated, and less knowledgeable about vehicle safety legislation. They anticipated fewer benefits, expected more barriers and were less likely to use booster seats. Simulations suggest that consistent enforcement coupled with advertising focusing on injury prevention and the use of booster seats by other parents would increase adoption. 相似文献
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The electrical and thermal conductivity of woven pristine and intercalated graphite fiber-polymer composites 总被引:1,自引:0,他引:1
A series of woven fabric laminar composite plates and narrow strips were fabricated from a variety of pitch-based pristine and bromine intercalated graphite fibers in an attempt to determine the influence of the weave on the electrical and thermal conduction. It was found generally that these materials can be treated as if they are homogeneous plates. The rule of mixtures describes the resistivity of the composite fairly well if it is realized that only the component of the fibers normal to the equipotential surface will conduct current. When the composite is narrow with respect to the fiber weave, however, there is a marked angular dependence of the resistance which was well modeled by assuming that the current follows only along the fibers (and not across them in a transverse direction), and that the contact resistance among the fibers in the composite is negligible. The thermal conductivity of composites made from less conductive fibers more closely followed the rule of mixtures than that of the high conductivity fibers, though this is thought to be an artifact of the measurement technique. Electrical and thermal anisotropy could be induced in a particular region of the structure by weaving together high and low conductivity fibers in different directions, though this must be done throughout all of the layers of the structure as interlaminar conduction precludes having only the top layer carry the anisotropy. The anisotropy in the thermal conductivity is considerably less than either that predicted by the rule of mixtures or the electrical resistivity. 相似文献
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