Periodic domain inversion and generation of blue light in lithium tantalate waveguides

Generation of blue light from small solid-state light sources is a technological challenge with applications in many areas, among others optical data storage. The authors report frequency doubling using third-order quasi-phase matching in periodically domain-inverted lithium tantalate waveguides. Periodic proton exchange followed by heat treatment caused periodic domain inversion and waveguide formation in a single step. Infrared radiation from a dye laser was coupled through the waveguides and second-harmonic generation corresponding to third-order quasi-phase-matching was observed.<>     

A feasibility study of solid supported enhanced microdialysis

For the first time, a solid supported enhanced microdialysis methodology for analysis of neuropeptides is described. The microdialysis samples were, in this study, subsequently collected in fractions, dissolved from the solid particles, dried, and resolved in a formic acid buffer in order to make them suitable for capillary liquid chromatography-mass spectrometry. Different microdialysis flow profiles were evaluated where air-gapped continuous flow was considered most suitable for the solid supported microdialysis mode. Six endogenous neuropeptides were initially used to investigate the feasibility of this enhanced microdialysis methodology. The improved relative recovery obtained from the solid supported enhanced microdialysis was varying from no effect to 10 times higher as compared to ordinary microdialysis. The most efficient enrichment was obtained for luteinizing hormone releasing hormone, which was the largest but also the most hydrophilic of the peptides. In contrast, no significant difference in recovery was observed for Leu-enkephalin being the smallest and the most hydrophobic peptide tested. These results indicate an increased flux and selective uptake of hydrophilic peptides across the membrane and enrichment on the particles in solid supported microdialysis.     

Disability disclosure effects on employment interview ratings of applicants with nonvisible disabilities.

Objective: To investigate the effects of timing of verbal disclosure of a disability on employment interview ratings of applicants with nonvisible disabilities. Study Design: Participants (56 college students) viewed 2 videotaped employment interviews: 1 involving an applicant who disclosed a nonvisible disability (transverse myelitis), either early or late in the interview, and 1 with an applicant who did not disclose a disability. Outcome Measures: Qualifications/hiring, liking, and comfort with disability disclosure scales. Results: Applicants with nonvisible disabilities who chose to disclosure their disability were rated as more qualified and likeable when disclosing early in an interview. Conclusion: Individuals who wish to disclose an externally caused nonvisible disability (similar to transverse myelitis) should consider doing so early in an interview rather than at the end. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Short- and long-term variations of norovirus concentrations in the Meuse river during a 2-year study period

Faecally impacted surface waters used for drinking water production may encompass risk for norovirus infections. To be able to assess a possible health risk, noroviruses should be quantified and fluctuations identified. In 2001, norovirus concentrations in the river Meuse displayed a seasonal distribution with high peaks during wintertime as determined by RT-PCR on serially diluted RNA. An intensified day-by-day sampling scheme in the winter of 2002/2003 revealed that the winter peak consisted of several peaks of varying duration and magnitude, possibly due to contamination events in the catchment. The highest estimated concentration was 1700 PCR-detectable units per litre (95% CI 250-8000), which if coinciding with failing treatment could lead to significant numbers in drinking water. Adaptive dynamic filtering was shown to adequately predict subsequent sample concentrations. If valid, such analyses could prove to be useful as early warning systems in risk management of water sources.     

Threshold-avoiding proteomics pipeline

We present a new proteomics analysis pipeline focused on maximizing the dynamic range of detected molecules in liquid chromatography-mass spectrometry (LC-MS) data and accurately quantifying low-abundance peaks to identify those with biological relevance. Although there has been much work to improve the quality of data derived from LC-MS instruments, the goal of this study was to extend the dynamic range of analyzed compounds by making full use of the information available within each data set and across multiple related chromatograms in an experiment. Our aim was to distinguish low-abundance signal peaks from noise by noting their coherent behavior across multiple data sets, and central to this is the need to delay the culling of noise peaks until the final peak-matching stage of the pipeline, when peaks from a single sample appear in the context of all others. The application of thresholds that might discard signal peaks early is thereby avoided, hence the name TAPP: threshold-avoiding proteomics pipeline. TAPP focuses on quantitative low-level processing of raw LC-MS data and includes novel preprocessing, peak detection, time alignment, and cluster-based matching. We demonstrate the performance of TAPP on biologically relevant sample data consisting of porcine cerebrospinal fluid spiked over a wide range of concentrations with horse heart cytochrome c.     

Achieving 0.2% relative expanded uncertainty in ion chromatography analysis using a high-performance methodology

A high-performance (HP) technique that was originally developed for inductively coupled plasma optical emission spectrometry (ICP-OES) has been successfully translated to ion chromatography (IC) to enable analyses with extremely low uncertainty. As an example application of the HP-IC methodology, analyses of several National Institute of Standards and Technology (NIST) Standard Reference Materials (SRMs) in the SRM 3180 series of anion standard solutions are reported. The relative expanded uncertainty values expressed at 95% confidence for these analyses range from 0.087% to 0.27% and average 0.18%. Strong correlation between analyte and internal standard anion peak heights or peak areas, as well as the use of a unique drift-correction approach, is shown to be important for attaining such low uncertainty.     

Glycosidases of wheat

Glycosidases isolated from the mill fractions made from soft and hard wheat grists were studied. α-Arabinosidase, α-galactosidase, β-galactosidase, β-glucosidase, β-glucuronidase, β-mannosidase and β-xylosidase activities in wheat flour, germ and bran were determined under standard dough conditions. There were no significant differences between the level of glycosidase activities from hard and soft grists. The level of a particular glycosidase activity was generally highest in the germ and lowest in the flour.