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Berührungslose RFID-Technologie wird weltweit für verschiedenste sicherheitsrelevante Anwendungen wie den Identit?tsnachweis oder Bezahlvorg?nge eingesetzt. Nach der Aufdeckung von Schwachstellen im kryptografischen Schutz der „ersten Generation“ kontaktloser SmartCards hoffte man auf die mit sicheren Chiffren versehenen Nachfolger. Der Beitrag zeigt die Anf?lligkeit kontaktloser SmartCards für Seitenkanalangriffe am Beispiel der Mifare DESFire MF3ICD40.  相似文献   
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A great deal of developmental research has relied on self-reports solicited using the “some/other” question format (“Some students think that… but other students think that…”). This article reports tests of the assumptions underlying its use: that it conveys to adolescents that socially undesirable attitudes, beliefs, or behaviors are not uncommon and legitimizes reporting them, yielding more valid self-reports than would be obtained by “direct” questions, which do not mention what other people think or do. A meta-analysis of 11 experiments embedded in four surveys of diverse samples of adolescents did not support the assumption that the some/other form increases validity. Although the some/other form led adolescents to think that undesirable attitudes, beliefs, or behaviors were more common and resulted in more reports of those attitudes and behaviors, answers to some/other questions were lower in criterion validity than were answers to direct questions. Because some/other questions take longer to ask and answer and require greater cognitive effort from participants (because they involve more words), and because they decrease measurement accuracy, the some/other question format seems best avoided. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Objective: As emotion regulation is widely considered to be a primary motive in the misuse of alcohol, our aim in the study was to investigate whether deficits in adaptive emotion-regulation skills maintain alcohol dependence (AD). Method: A prospective study investigated whether emotion-regulation skills were associated with AD and whether these skills predicted alcohol use during and after treatment for AD. Participants were 116 individuals treated for AD with cognitive–behavioral therapy. Emotion regulation and severity of AD symptoms were assessed by self-report. Alcohol use during treatment was assessed by Breathalyzer and urine analysis for ethyl glucuronide; alcohol use during the 3-month follow-up interval was assessed by self-report. Results: Pretreatment emotion-regulation skills predicted alcohol use during treatment, and posttreatment emotion-regulation skills predicted alcohol use at follow-up, even when controlling for other predictors potentially related to emotion regulation. Among a broad range of specific emotion-regulation skills, the ability to tolerate negative emotions was the only skill that negatively predicted subsequent alcohol consumption when controlling for the other skills. Individuals in the AD sample reported significantly larger deficits in emotion-regulation skills than did those in a nonclinical control sample but significantly less than did those in a sample of individuals exclusively meeting criteria for major depressive disorder. Conclusions: Enhancement of general emotion-regulation skills, especially the ability to tolerate negative emotions, appears to be an important target in the treatment of AD. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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The identification and production of recombinant morphogens and growth factors that play key roles in tissue regeneration have generated much enthusiasm and numerous clinical trials, but the results of many of these trials have been largely disappointing. Interestingly, the trials that have shown benefit all contain a common denominator, the presence of a material carrier, suggesting strongly that spatio-temporal control over the location and bioactivity of factors after introduction into the body is crucial to achieve tangible therapeutic effect. Sophisticated materials systems that regulate the biological presentation of growth factors represent an attractive new generation of therapeutic agents for the treatment of a wide variety of diseases. This review provides an overview of growth factor delivery in tissue engineering. Certain fundamental issues and design strategies relevant to the material carriers that are being actively pursued to address specific technical objectives are discussed. Recent progress highlights the importance of materials science and engineering in growth factor delivery approaches to regenerative medicine.  相似文献   
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