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31.
We report on the specific interaction between DNA and some mica-family minerals and other layered silicate structures. The interaction depends on mineral surface's crystallography, chemistry and potential. These properties are responsible for a remarkable variety of adsorption mechanisms and can be used to modulate surface self-assembly and nanopatterning of DNA. The controlled deposition of DNA onto non-conductive mineral regions with atomically flat boundaries has very attractive applications in nano-biotechnology (for example, microelectronics, microarrays and sensors). In addition, the extreme affinity discovered for some mineral surfaces, together with their ability to organize the DNA molecules, could be an indication of their catalytic potential. It may also have had relevance in the prebiotic environment, with important implications for the earth and life sciences.  相似文献   
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One of the most exciting developments in intergroup contact theory is the idea that a certain type of contact, cross-group friendship, might be particularly effective at reducing prejudice. In this chapter we review research on two types of cross-group friendship. Direct cross-group friendship refers to friendships that develop between members of different groups. Extended cross-group friendship, on the other hand, refers to vicarious experience of cross-group friendship, the mere knowledge that other ingroup members have cross-group friends. We consider the relationship between both types of cross-group friendship and prejudice and the processes that mediate and moderate these relationships. The research highlights the respective strengths and weaknesses of direct and extended cross-group friendship and illustrates how they might be practically combined in efforts to improve intergroup relations.  相似文献   
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Albino rats in independent studies were administered varying dosages of diazepam and methylphenidate prior to a daily shock traumatization experience in infancy. All animals were tested on avoidance conditioning in adulthood. Both drugs were found to be effective in modifying the typically obtained shock deficit. The results failed to substantiate that increased dosage level resulted in more effective modification of trauma effects. Delayed consequences of methylphenidate administration included modification of central nervous system reactivity as manifested in quicker reaction times and growth depression as manifested in lessened body weights in this group in comparison to the diazepam group. An additional feature of the study was the finding that male and female animals responded differently to the drug and shock experiences.  相似文献   
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