49,813 research outputs found
Nocturia, other lower urinary tract symptoms (LUTS), and sleep dysfunction in a community-dwelling cohort of middle-aged to elderly men
No full textPodium Oral Abstracts - 33S. Martin, S. Appleton, R. Adams, A. Taylor, P. Catcheside, A. Vakulin, D. Mcevoy, N. Antic, and G. Witter
p-n Junction Formation in i-Ge Crystal by Laser Radiation
No full textP-n junction is the main component of many semiconductor devices. Thermodiffusion, ion implantation and molecular beam epitaxy are only a few methods to form a p-n junction. The main drawback for these methods is high cost per p-n junction since the equipment for these methods is expensive. A possibility of p-n junction formation by laser radiation was shown in several p- and n-type semiconductors: p-Si[1,2], p-CdTe[3], p-InSb[4,5], p-InAs[6], p-PbSe[7] and p-Ge[8] due to inversion of conductivity type. Unfortunately, the mechanism of p-n junction formation by laser radiation is not clear until now.
In the present research rectification effect of current-voltage characteristic in pure intrinsic Ge crystal after irradiation by Nd:YAG laser was observed. The effect is characterised by threshold intensity of the laser radiation. Increase of rectification ratio of current-voltage characteristics and barrier height with intensity of the laser radiation, energy of laser radiation quanta and number of pulses was observed in this experiment. The mechanism of this phenomenon is explained by generation and redistribution of intrinsic point defects in temperature gradient field, which causes strongly absorbed laser radiation. The redistribution of defects takes place because interstitial atoms drift towards the irradiated surface, but vacancies drift in the opposite direction – in the bulk of semiconductor according to Thermogradient effect. Since interstitials in Ge crystal are of n-type and vacancies are known to be of p-type, a p-n junction is formed.
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[5] A. Medvid‘ et al. Vacuum, 51, 245 (1998).
[6] L. Kurbatov et al. Reports of Acad. Sc.USSR, 268, 594 (1983)
[7] K.D. Tovstyuk et al. Ukrainian Journal of Physics, 21, 1918 (1984).
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Acknowledgments.
The author gratefully acknowledges financial support in part by Europe Project in the Framework of MATERA+ project, European Regional Development Fund within the project “Sol-gel and laser technologies for the development of nanostructures and barrier structures”, the ESF Projects No. 1DP/1.1.1.2.0/09/ APIA/VIAA/142 and «Support for the implementation of doctoral studies at Riga Technical University»
Experimental investigation into the effect of substrate clamping on the piezoelectric behaviour of thick-film PZT elements
No full textThis paper details an experimental investigation of the clamping effect associated with thick-film piezoelectric elements printed on a substrate. The clamping effect reduces the measured piezoelectric coefficient, d33, of the film. This reduction is due to the influence of the d31 component in the film when a deformation of the structure occurs, by either the direct or indirect piezoelectric effect. Theoretical analysis shows a reduction in the measured d33 of 62%, i.e. a standard bulk lead zirconate titanate (PZT)-5H sample with a manufacturer specified d33 of 593pC/N would fall to 227.8pC/N. To confirm this effect, the d33 coefficients of five thin bulk PZT-5H samples of 220µm thickness were measured before and after their attachment to a metallized 96% alumina substrate. The experimental results show a reduction in d33 of 74% from 529pC/N to 139pC/N. The theoretical analysis was then applied to existing University of Southampton thick-film devices. It is estimated that the measured d33 value of 131pC/N of the thick-film devices is the equivalent of an unconstrained d33 of 345pC/N
Identification of clinical phenotypes In Obstructive Sleep Apnea (OSA) using cluster analysis: a population study
No full textAbstract: Sleep and Physiology Sig – Oral Presentations TO 108Adams R, Appleton S, Vincent A, Vakulin A, Antic N, Mcevoy D, Catcheside P, Martin S, Grant J, Taylor A, Wittert
Obstructive sleep apnea is associated with incident pre-diabetes in a population cohort of men
No full textAbstract - B99. Randomized controlled and prospective clinical trials in sleep disordered breathing / Mini SymposiumR. Adams, S. Appleton, A. Vakulin, D. McEvoy, N. A. Antic, P. Catcheside, J. Grant, S. Martin, A. Taylor, G. Witter
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Charles F. Foster, Four Cheshire Townships in the 18th Century : Arley, Appleton, Stockton Healt and Great Budworth
No full textPoussou Jean-Pierre. Charles F. Foster, Four Cheshire Townships in the 18th Century : Arley, Appleton, Stockton Healt and Great Budworth. In: Annales. Histoire, Sciences Sociales. 51ᵉ année, N. 2, 1996. p. 370
NMN adenylyltransferase and poly (ADP-Ribose) polymerase in bovine tissues and characterization of NMN adenylyltransferase from bull testis
No full textHematodinium infection seasonality in the Firth of Clyde (Scotland) nephrops norvegicus population: a re-evaluation
No full textHematodinium infections in Norway lobster Nephrops norvegicus from the Clyde Sea area (CSA) population, Scotland, UK, have previously been undetected in summer. This study aimed to establish if the CSA is actually devoid of infected N. norvegicus in this season. Two PCR assays, an ELISA and 2 tests that detect only patent infection (pleopod and body colour methods) were applied in a 21 mo study. Patent infection was seasonal, appearing predominantly in spring, while subpatent infection diagnosed by ELISA and PCR was highly prevalent in all seasons. Generalised linear modelling supported this assertion, as sampling in September and February significantly increased the probability of finding infected N. norvegicus (p < 0.01); infections were predominantly subpatent and patent respectively, at these times. Therefore, Hematodinium seasonality in N. norvegicus populations is likely to have been an artefact of insensitive diagnostic tests. Light Hematodinium infections were found using PCR assays when patent infections were at their most prevalent and intense, suggesting that infection develops at different rates in different N. norvegicus individuals and that only a portion of the total number of infected N. norvegicus die within a single year. These new data were added to a long-term data series for the CSA (1990 to 2008), which showed that after an initial 5 yr epidemic period, prevalence stabilised at 20 to 25%. Comparisons with ‘susceptible-infected-recovered/removed’ (SIR) models suggest that this high prevalence is maintained through high birth rates of susceptible host N. norvegicus
Effects of n\u963 long-chain polyunsaturated fatty acids on depressed mood: systematic review of published trials
No full textEffects of n\u963 long-chain polyunsaturated fatty acids on depressed mood: systematic review of published trials1,2,3
Katherine M Appleton, Robert C Hayward, David Gunnell, Tim J Peters, Peter J Rogers, David Kessler and Andrew R Ness
1 From the Department of Experimental Psychology (KMA, RCH, and PJR), the Department of Social Medicine (DG and ARN), and the Academic Unit of Primary Health Care, Department of Community Based Medicine (TJP and DK), University of Bristol, Bristol, United Kingdom
Background: Greater dietary intakes of n\u963 long-chain polyunsaturated fatty acids (n\u963 PUFAs) may be beneficial for depressed mood.
Objective: This study aimed to systematically review all published randomized controlled trials investigating the effects of n\u963 PUFAs on depressed mood.
Design: Eight medical and health databases were searched over all years of records until June 2006 for trials that exposed participants to n\u963 PUFAs or fish, measured depressed mood, were conducted on human participants, and included a comparison group.
Results: Eighteen randomized controlled trials were identified; 12 were included in a meta-analysis. The pooled standardized difference in mean outcome (fixed-effects model) was 0.13 SDs (95% CI: 0.01, 0.25) in those receiving n\u963 PUFAs compared with placebo, with strong evidence of heterogeneity (I2 =3D 79%, P < 0.001). The presence of funnel plot asymmetry suggested that publication bias was the likely source of heterogeneity. Sensitivity analyses that excluded one large trial increased the effect size estimates but did not reduce heterogeneity. Metaregression provided some evidence that the effect was stronger in trials involving populations with major depression\u97the difference in the effect size estimates was 0.73 (95% CI: 0.05, 1.41; P =3D 0.04), but there was still considerable heterogeneity when trials that involved populations with major depression were pooled separately (I2 =3D 72%, P < 0.001).
Conclusions: Trial evidence that examines the effects of n\u963 PUFAs on depressed mood is limited and is difficult to summarize and evaluate because of considerable heterogeneity. The evidence available provides little support for the use of n\u963 PUFAs to improve depressed mood. Larger trials with adequate power to detect clinically important benefits are required
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