			Home About us Contact

Reduced Sample (reduced + sample)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Effect of reduction/oxidation treatment on blue photorefraction in In:Fe:Cu:LiNbO3 crystals

CRYSTAL RESEARCH AND TECHNOLOGY, Issue 4 2010
Suhua Luo
Abstract In:Fe:Cu:LiNbO3 crystals with reduced/oxidized treatments were prepared by the Czochralski method. The defect structure was analyzed by the UV-Visible absorption spectra. The blue photorefractive properties, such as the refractive index change, response time, recording sensitivity, dynamic range as well as two-wave coupling gain coefficient, were also investigated at 488 nm wavelength using the two-wave coupling experiment. Comparing the as-grown and oxidized In:Fe:Cu:LiNbO3 crystals, the reduced sample has the highest recording sensitivity and largest dynamic range. Meanwhile, the high diffraction efficiency is still maintained. Experimental results definitely show that reduction treatment is an effective method to improve the blue photorefractive performance of In:Fe:Cu:LiNbO3 crystals. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

On-line sample preconcentration with chemical derivatization of bacterial biomarkers by capillary electrophoresis: A dual strategy for integrating sample pretreatment with chemical analysis

ELECTROPHORESIS, Issue 21 2005
Adam S. Ptolemy
Abstract Simple, selective yet sensitive methods to quantify low-abundance bacterial biomarkers derived from complex samples are required in clinical, biological, and environmental applications. In this report, a new strategy to integrate sample pretreatment with chemical analysis is investigated using on-line preconcentration with chemical derivatization by CE and UV detection. Single-step enantioselective analysis of muramic acid (MA) and diaminopimelic acid (DAP) was achieved by CE via sample enrichment by dynamic pH junction with ortho -phthalaldehyde/N -acetyl- L -cysteine labeling directly in-capillary. The optimized method resulted in up to a 100-fold enhancement in concentration sensitivity compared to conventional off-line derivatization procedures. The method was also applied toward the detection of micromolar levels of MA and DAP excreted in the extracellular medium of Escherichia coli bacterial cell cultures. On-line preconcentration with chemical derivatization by CE represents a unique approach for conducting rapid, sensitive, and high-throughput analyses of other classes of amino acid and amino sugar metabolites with reduced sample handling, where the capillary functions simultaneously as a concentrator, microreactor, and chiral selector. [source]

A dose-response relationship between maternal smoking during late pregnancy and adult intelligence in male offspring

PAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2005
Erik Lykke Mortensen
Summary An association between maternal smoking during pregnancy and cognitive and behavioural development has been observed in several studies, but potential effects of maternal smoking on offspring adult intelligence have not been investigated. The objective of the present study was to investigate a potential association between maternal smoking during pregnancy and offspring intelligence in young adulthood. Adult intelligence was assessed at the mean age of 18.7 years by a military draft board intelligence test (Børge Priens Prøve) for 3044 singleton males from the Copenhagen Perinatal Cohort with information regarding maternal smoking during the third trimester coded into five categories (about 50% of the mothers were smokers). The following potential confounders were included as covariates in multivariable analyses: parental social status and education, single mother status, mother's height and age, number of pregnancies, and gestational age. In separate analyses, birthweight and length were also included as covariates. Maternal cigarette smoking during the third trimester, adjusted for the seven covariates, showed a negative association with offspring adult intelligence (P = 0.0001). The mean difference between the no-smoking and the heaviest smoking category amounted to 0.41 standard deviation, corresponding to an IQ difference of 6.2 points [95% confidence interval 0.14, 0.68]. The association remained significant when further adjusted for birthweight and length (P = 0.007). Both unadjusted and adjusted means suggested a dose-response relationship between maternal smoking during pregnancy and offspring adult intelligence. When subjects with missing data were excluded, essentially the same results were obtained in the reduced sample (n = 1829). These results suggest that smoking during pregnancy may have long-term negative consequences on offspring adult intelligence. [source]

The CUPDAY Study: prebiotic-probiotic milk product in 1,3-year-old children attending childcare centres

ACTA PAEDIATRICA, Issue 11 2007
CW Binns
Abstract Aim: The aim of the study was to evaluate the efficacy of a milk product containing probiotics and prebiotics (CUPDAY Milk) on the incidence of diarrhoea in children attending daycare centres. Methods: The study was undertaken in a randomized controlled trial with 496 children aged 1,3 years attending 29 childcare centres in Perth, Australia. The endpoint for the study was the number of days in which children were recorded as having four or more stools. The diarrhoeal rates were analyzed by Poisson regression using ,intention to treat' (all children) and ,reduced' (children enrolled for more than 10 days) data sets. Results: There was no difference in demographic characteristics between the case and control groups. In the ,intention to treat' analysis, a total of 41 745 child-days were included in the study. The adjusted risk ratio for those consuming the ,Cupday' milk drink was 0.82 (95% CI 0.73,0.94) for the intention to treat sample (n = 496) and 0.80 (95% CI 0.70,0.91) for the reduced sample (n = 315). The children consuming the ,Cupday' drink had a 20% reduction in the number of days experiencing four or more stools per day. Conclusion: A milk containing probiotics and prebiotics reduced the number of days children attending child care who had four or more stools by 20%. [source]