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Background: We hypothesized that RX246, a vasopressin V1a receptor antagonist, blocks the effect of intranasally administered vasopressin on brain processing of angry Ekman faces. An interaction of intranasal and oral drug was predicted in the amygdala. Methods: Twenty-nine consenting right handed healthy male subjects received a baseline fMRI scan while they viewed angry faces. Subsequently, they were randomized to receive oral SRX246 (120mg PO twice a day) or placebo. After an average of 7 days of treatment (range 5-11 days), they were given an acute dose of intranasal vasopressin (40 I.U) or placebo and underwent a second scan 60 min later. The primary outcome was BOLD activity in the amygdala in response to angry faces. Secondary analyses were focused on ROIs in a brain regions previously linked to vasopressin signaling. Results: In subjects randomized to oral placebo-intranasal vasopressin, there was a significantly diminished amygdala BOLD response from the baseline to post-drug scan compared with oral placebo-intranasal placebo subjects. RM-ANOVA of the BOLD signal changes in the amygdala revealed a significant oral drug x intranasal drug x session interaction (F (1, 25) = 4.353, p

BACKGROUND: Uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal Cry proteins of Bacillus thuringiensis (Bt). We performed meta-analyses on a modified public database to synthesize current knowledge about the effects of Bt cotton, maize and potato on the abundance and interactions of arthropod non-target functional guilds. METHODOLOGY/PRINCIPAL FINDINGS: We compared the abundance of predators, parasitoids, omnivores, detritivores and herbivores under scenarios in which neither, only the non-Bt crops, or both Bt and non-Bt crops received insecticide treatments. Predators were less abundant in Bt cotton compared to unsprayed non-Bt controls. As expected, fewer specialist parasitoids of the target pest occurred in Bt maize fields compared to unsprayed non-Bt controls, but no significant reduction was detected for other parasitoids. Numbers of predators and herbivores were higher in Bt crops compared to sprayed non-Bt controls, and type of insecticide influenced the magnitude of the difference. Omnivores and detritivores were more abundant in insecticide-treated controls and for the latter guild this was associated with reductions of their predators in sprayed non-Bt maize. No differences in abundance were found when both Bt and non-Bt crops were sprayed. Predator-to-prey ratios were unchanged by either Bt crops or the use of insecticides; ratios were higher in Bt maize relative to the sprayed non-Bt control. CONCLUSIONS/SIGNIFICANCE: Overall, we find no uniform effects of Bt cotton, maize and potato on the functional guilds of non-target arthropods. Use of and type of insecticides influenced the magnitude and direction of effects; insecticde effects were much larger than those of Bt crops. These meta-analyses underscore the importance of using controls not only to isolate the effects of a Bt crop per se but also to reflect the replacement of existing agricultural practices. Results will provide researchers with information to design more robust experiments and will inform the decisions of diverse stakeholders regarding the safety of transgenic insecticidal crops.

We consider how changing attitudes to computer use may alter the habits of students in the use of location and times of the day. We discover for one community the extent to which they absent themselves from the physical university and see some trends. We suggest that this is a deep change of habit, influenced by the "digital generation", and seek qualitative results on what determines the modern student's keyboard behaviour. We present early evidence that, while students are indeed absenting themselves from formal computer facilities, some understanding of the benefits of the physical university remains intact. (Contains 1 note and 4 figures.)

The objective of this study was to examine substance use and HIV risk behaviors among a community sample of Black and Coloured South Africans. Eligible participants aged 18 and above were recruited from one historically Black and one historically Coloured township in Cape Town. Blacks and Coloureds were about equally as likely to use at least one soft drug (e.g., cannabis). Coloureds were more likely to use at least one hard drug, with methamphetamines being most common. Alcohol before sex was the primary 'driver' of having unprotected sex and served as a mediator of other risk factors such as drug use before sex and problem drinking. Furthermore, hard drug users were much more likely to use soft drugs than vice versa. The independent and mediating role of soft drugs suggest that soft drug (vs. hard drug) use should not be overlooked at least in the context of HIV prevention.