Understanding Bulk Defects in Topological Insulators from Nuclear‐Spin Interactions

Non‐invasive local probes are needed to characterize bulk defects in binary and ternary chalcogenides. These defects contribute to the non‐ideal behavior of topological insulators. The bulk electronic properties are studied via ¹²⁵Te NMR in Bi₂Te₃, Sb₂Te₃, Bi_0.5Sb_1.5Te₃, Bi₂Te₂Se, and Bi₂Te₂S. A distribution of defects gives rise to asymmetry in the powder lineshapes. The Knight shift, line shape, and spin‐lattice relaxation are investigated in terms of how they affect carrier density, spin‐orbit coupling, and phase separation in the bulk. The present study confirms that the ordered ternary compound Bi₂Te₂Se is the best topological insulator candidate material at the present time. These results, which are in good agreement with transport and angle‐resolved photoemission spectroscopy studies, help establish the NMR probe as a valuable method to characterize the bulk properties of these materials.     

Src64 is required for ovarian ring canal morphogenesis during Drosophila oogenesis

The Src family of protein tyrosine kinases have been implicated as important regulators of cellular proliferation, differentiation and function. In order to understand further the role of Src family kinases, we have generated loss-of-function mutations in Src64, one of two Src family kinases known in Drosophila melanogaster. Animals with reduced Src64 function develop normally and are fully viable. However, Src64 female flies have reduced fertility, which is associated with the incomplete transfer of cytoplasm from nurse cells to the developing oocyte. Analysis of Src64 egg chambers showed defects in the ring canals that interconnect the oocyte and its 15 associated nurse cells. Src64 ring canals fail to accumulate the high levels of tyrosine phosphorylation that are normally present. Despite the reduced tyrosine phosphorylation, known ring canal components such as filamentous actin, a ring canal-specific product of the hu-li tai shao gene, and the kelch protein localize properly. However, Src64 ring canals are reduced in size and frequently degenerate. These results indicate that Src64 is required for the proper growth and stability of the ovarian ring canals.     

Investigation of cellulose convertibility and ethanolic fermentation of sugarcane bagasse pretreated by wet oxidation and steam explosion

Sugarcane bagasse was pretreated by wet oxidation (WO) at 195 °C for 15 min under either alkaline, neutral or acidic conditions, and by steam explosion (STEX) at 205 °C for 10 min. Alkaline WO was more favourable than neutral and acidic WO for the following enzymatic hydrolysis of cellulose, giving 792 g kg^?1 glucose yield after 48 h. The enzymatic hydrolysis of the fibres in the whole slurry was inhibited by inhibitory compounds contained in the prehydrolysate in comparison with the hydrolysis of the washed solid fibres in buffer. The inhibition increased proportionally with formic acid concentration in the pretreated liquid fraction. Cellulose conversion was higher for simultaneous saccharification and fermentation (SSF) than for separate hydrolysis. The highest SSF conversion (829 g kg^?1) was obtained for the material treated by alkaline WO. The fermentability of the prehydrolysates by Saccharomyces cerevisiae was evaluated. Stronger inhibition of ethanolic fermentation was observed in the prehydrolysate obtained by steam explosion. The inhibition was more noticeable for the volumetric productivity than for the ethanol yield. The volumetric productivity was reduced by 94.5 and 91.2% for STEX and WO, respectively, whereas the ethanol yield was reduced only by 45.2 and 31.0%, correspondingly, for STEX and WO. Furan aldehydes seemed to be mainly responsible for the inhibition of the fermentation. Copyright © 2006 Society of Chemical Industry     

The economic 'revolution' in Melbourne's west

Historically, Melbourne's western suburbs were known as industrial areas suffering from relative disadvantage when compared to the rest of the metropolitan area. But economic commentators have claimed that a resurgence has occurred in the west, in terms of industrial investment and employment generation, since the mid-1990s, due to increasingly globalised economic connections which have reversed the region's previous disadvantages. This article engages with these 'western resurgence' claims in three ways. First, it examines the recent economic history of the western region, relative to global economic processes. Second the article examines the empirical basis for the reported recent economic resurgence in the west. Finally, the article concludes with some observations concerning regional economic development under contemporary global processes.     

High-level expression and characterization of a glycosylated covalently linked dimer of the prion protein

There is evidence that prion protein dimers may be involvedin the formation of the scrapie prion protein, PrP^Sc, from itsnormal (cellular) form, PrP^c. Recently, the crystal structureof the human prion protein in a dimeric form was reported. Herewe report for the first time the overexpression of a human PrPdimer covalently linked by a FLAG peptide (PrP::FLAG::PrP) inthe methylotrophic yeast Pichia pastoris. FLAG-tagged humanPrP (aa1-aa253) (huPrP::FLAG) was also expressed in the samesystem. Treatment with tunicamycin and endoglycosidase H showedthat both fusion proteins are expressed as various glycoforms.Both PrP proteins were completely digested by proteinase K (PK),suggesting that the proteins do not have a PrP^Sc structure andare not infectious. Plasma membrane fractionation revealed thatboth proteins are transported to the plasma membrane of thecell. The glycosylated proteins might act as powerful toolsfor crystallization trials, PrP^c/PrP^Sc conversion studies andother applications in the life cycle of prions.     

Enhancing Treatment Fidelity in Health Behavior Change Studies: Best Practices and Recommendations From the NIH Behavior Change Consortium.

Treatment fidelity refers to the methodological strategies used to monitor and enhance the reliability and validity of behavioral interventions. This article describes a multisite effort by the Treatment Fidelity Workgroup of the National Institutes of Health Behavior Change Consortium (BCC) to identify treatment fidelity concepts and strategies in health behavior intervention research. The work group reviewed treatment fidelity practices in the research literature, identified techniques used within the BCC, and developed recommendations for incorporating these practices more consistently. The recommendations cover study design, provider training, treatment delivery, treatment receipt, and enactment of treatment skills. Funding agencies, reviewers, and journal editors are encouraged to make treatment fidelity a standard part of the conduct and evaluation of health behavior intervention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Drought refuges affect algal recolonization in intermittent streams

Drought refuges enable the biota of intermittent streams to survive dry periods, but their roles in sustaining algal assemblage structure and productivity are not known. This study determined the importance of two types of drought refuge (dry biofilm, permanent pools) for benthic algal regrowth in four intermittent streams in the Grampians National Park, Victoria, Australia. Dry biofilm was removed by scrubbing randomly chosen stones from two dry riffles in each of two streams with permanent pools and two streams without permanent pools. Algae were sampled from scrubbed and control stones at one, six and sixteen weeks after flow resumed. Removal of dry algal biofilm resulted in lower algal densities on stones from both stream types, and scrubbed stones had similar densities of algae after one week, regardless of the presence or absence of permanent pools. Algal density on stones exposed to both refuge types was more than an order of magnitude higher than the density on stones exposed to either one or neither refuge. The effects of biofilm removal on algal density were still apparent after six weeks of flow and assemblage composition differed between streams with and without permanent pools. Dry biofilm was an important drought refuge for algae in both stream types, but epilithic algal density in streams with permanent pools developed more rapidly than streams that were completely dry over summer. Loss of permanent pools from intermittent streams due to water abstraction may substantially reduce algal productivity after flow resumes, which may limit the supply of autochthonous carbon. Copyright © 2004 John Wiley & Sons, Ltd.     

Multicenter trial of fluoxetine as an adjunct to behavioral smoking cessation treatment.

The authors evaluated the efficacy of fluoxetine hydrochloride (Prozac; Eli Lilly and Company, Indianapolis, IN) as an adjunct to behavioral treatment for smoking cessation. Sixteen sites randomized 989 smokers to 3 dose conditions: 10 weeks of placebo, 30 mg, or 60 mg fluoxetine per day. Smokers received 9 sessions of individualized cognitive-behavioral therapy, and biologically verified 7-day self-reported abstinence follow-ups were conducted at 1, 3, and 6 months posttreatment. Analyses assuming missing data counted as smoking observed no treatment difference in outcomes. Pattern-mixture analysis that estimates treatment effects in the presence of missing data observed enhanced quit rates associated with both the 60-mg and 30-mg doses. Results support a modest, short-term effect of fluoxetine on smoking cessation and consideration of alternative models for handling missing data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)