An atomic scale study of Si-doped AlAs by cross-sectional scanning tunneling microscopy and density functional theory

Silicon (Si) donors in GaAs have been the topic of extensive studies since Si is the most common and well understood n-type dopant in III-V semiconductor devices and substrates. The indirect bandgap of AlAs compared to the direct one of GaAs leads to interesting effects when introducing Si dopants. Here we present a study of cross-sectional scanning tunneling microscopy (X-STM) and density functional theory (DFT) calculations to study Si donors in AlAs at the atomic scale. Based on their crystal symmetry and contrast strengths, we identify Si donors up to four layers below the (110) surface of AlAs. Interestingly, their short-range local density of states (LDOS) is very similar to Si atoms in the (110) surface of GaAs. Additionally we show high-resolution images of Si donors in all these layers. For empty state imaging, the experimental and simulated STM images based on DFT show excellent agreement for Si donor up to two layers below the surface

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Response of alewives to high frequency sound at a power plant intake on Lake Ontario

From April through June 1991, we tested a full-scale deterrent system for excluding alewives (Alosa pseudoharengus) from the intake of the James A. FitzPatrick Nuclear Power Plant (JAF), near Oswego, New York. This electronic system produced high-frequency broadband sound (122-128 kHz) at a source level (in decibels (dB) in reference to 1 mu Pa) of190 dB. When the system was on, the density of fish near the JAF intake decreased by as much as 96% and the number of alewives impinged on the intake screens at JAF decreased by as much as 87%. The system was effective during both day and night, and its range was greater than 80 m

Treating disturbances in the relationship between mothers with bulimic eating disorders and their infants: a randomized, controlled trial of video feedback.

OBJECTIVE: Maternal eating disorders interfere with parenting, adversely affecting mother-infant interaction and infant outcome. This trial tested whether video-feedback treatment specifically targeting mother-child interaction would be superior to counseling in improving mother-child interaction, especially mealtime conflict, and infant weight and autonomy. METHOD: The participants were 80 mothers with bulimia nervosa or similar eating disorder who were attending routine baby clinics and whose infants were 4-6 months old. They were randomly assigned to video-feedback interactional treatment or supportive counseling. Both groups also received guided cognitive behavior self-help for their eating disorder. Each group received 13 sessions. The primary outcome measure was mealtime conflict; secondary outcome measures were infant weight, aspects of mother-infant interaction, and infant autonomy. RESULTS: Seventy-seven mothers were followed up when their infants were 13 months old. The video-feedback group exhibited significantly less mealtime conflict than the control subjects. Nine of 38 (23.7%) in the video-feedback group showed episodes of marked or severe conflict, compared with 21 of 39 (53.8%) control subjects (odds ratio=0.27, 95% confidence interval=0.10 to 0.73). Video feedback produced significant improvements in several other interaction measures and greater infant autonomy. Both groups maintained good infant weight, with no differences between groups. Maternal eating psychopathology was reduced across both groups. CONCLUSIONS: Video-feedback treatment focusing on mother-infant interaction produced improvements in interaction and infant autonomy, and both groups maintained adequate infant weight. To the authors' knowledge, this is the first controlled trial to show key improvements in interaction between mothers with postnatal psychiatric disorders and their infants