The role of positive selection in human evolution remains controversial. On the one hand, scans for positive selection have identified hundreds of candidate loci, and the genome-wide patterns of polymorphism show signatures consistent with frequent positive selection. On the other hand, recent studies have argued that many of the candidate loci are false positives and that most genome-wide sign...

fMR adaptation in the ventral visual pathway reflects information processing that may contribute to implicit and explicit memory. In experiments that employed <1 s repetition lag, we found that attention increases adaptation for repeated objects in brain regions at the top of the visual processing hierarchy (anterior fusiform and parahippocampal gyri) but that it can still appear with minimal a...

this study has emphasized the importance of family training on: 1) adaptation of patieants in everyday life, 2) increasing family knowledge and, 3) reducing family negative attitude toward this illness. using a questionnaire and clinical interview, 30 families were studied in 3 groups, which wre matched regarding the patients sex, age, education, social class and dagnosis. the results showed th...

Aftereffects have been documented for a variety of perceptual categories spanning from body gender to facial emotion, thus becoming an important tool in the study of high-level vision and its neural bases. We examined whether the perceived valence of a complex scene is subject to aftereffects, by observing the participants' evaluation of the valence of a test picture preceded by a different pic...

Placed in the context of China’s transitional economy, this paper studies the role of different economic, institutional and managerial factors in accelerating or hindering hightechnology firms’ pace of strategic adaptation toward a higher level of technology orientation. Drawing on a unique longitudinal data of firms in the Zhongguancun Science Park (China’s Silicon Valley) from 2000 to 2003, w...

It is often argued that high mutation rates are advantageous for RNA viruses, because they confer elevated rates of adaptation. However, there is no direct evidence showing a positive correlation between mutation and adaptation rates among RNA viruses. Moreover, theoretical work does not argue in favor of this prediction. We used a series of vesicular stomatitis virus clones harboring single am...

There are two basic types of bacterial communication systems--those in which the signal is directed solely at other organisms and those in which the signal is sensed by the producing organism as well. The former are involved primarily in conjugation; the latter in adaptation to the environment. Gram-positive bacteria use small peptides for both types of signaling, whereas Gram-negative bacteria...

The sera of school children with Schistosoma haematobium infection were tested for the presence of cold-insoluble immune complexes "the cryoglobulins". Two different methods were used: the standard macro-technique and the micro-adaptation technique. On using the standard macro-technique, 40 (32.8%) out of 122 schistosomiasis patients and 6 (7.5%) out of 80 control children were positive for cry...

BACKGROUND Having identified substance abuse as an issue of concern in their community, the Alexis Nakota Sioux Nation invited University of Alberta researchers to partner on the cultural adaptation, delivery, and evaluation of a school-based drug and alcohol abuse prevention program. Researchers conducted a literature review of available drug and alcohol prevention programs for children and yo...