4,038 research outputs found

    Inherent-Structure Dynamics and Diffusion in Liquids

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    The self-diffusion constant D is expressed in terms of transitions among the local minima of the potential (inherent structure, IS) and their correlations. The formulae are evaluated and tested against simulation in the supercooled, unit-density Lennard-Jones liquid. The approximation of uncorrelated IS-transition (IST) vectors, D_{0}, greatly exceeds D in the upper temperature range, but merges with simulation at reduced T ~ 0.50. Since uncorrelated IST are associated with a hopping mechanism, the condition D ~ D_{0} provides a new way to identify the crossover to hopping. The results suggest that theories of diffusion in deeply supercooled liquids may be based on weakly correlated IST.Comment: submitted to PR

    Electromagnetic properties of material coated surfaces

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    The electromagnetic properties of material coated conducting surfaces were investigated. The coating geometries consist of uniform layers over a planar surface, irregularly shaped formations near edges and randomly positioned, electrically small, irregularly shaped formations over a surface. Techniques to measure the scattered field and constitutive parameters from these geometries were studied. The significance of the scattered field from these geometries warrants further study

    Muon spin rotation studies of niobium for superconducting RF applications

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    In this work we investigate superconducting properties of niobium samples via application of the muon spin rotation/relaxation (muSR) technique. We employ for the first time the muSR technique to study samples that are cutout from large and small grain 1.5 GHz radio frequency (RF) single cell niobium cavities. The RF test of these cavities was accompanied by full temperature mapping to characterize the RF losses in each of the samples. Results of the muSR measurements show that standard cavity surface treatments like mild baking and buffered chemical polishing (BCP) performed on the studied samples affect their surface pinning strength. We find an interesting correlation between high field RF losses and field dependence of the sample magnetic volume fraction measured via muSR. The muSR line width observed in ZF-muSR measurements matches the behavior of Nb samples doped with minute amounts of Ta or N impurities. An upper bound for the upper critical field Hc2 of these cutouts is found.Comment: 20 pages, 14 figure

    Protocol for a national monthly survey of alcohol use in England with 6-month follow-up: 'The Alcohol Toolkit Study'.

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    Timely tracking of national patterns of alcohol consumption is needed to inform and evaluate strategies and policies aimed at reducing alcohol-related harm. Between 2014 until at least 2017, the Alcohol Toolkit Study (ATS) will provide such tracking data and link these with policy changes and campaigns. By virtue of its connection with the 'Smoking Toolkit Study' (STS), links will also be examined between alcohol and smoking-related behaviour

    Use of aids for smoking cessation and alcohol reduction: A population survey of adults in England.

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    BACKGROUND: It is important for policy planning to chart the methods smokers and high-risk drinkers use to help them change their behaviour. This study assessed prevalence of use, and characteristics of users, of support for smoking cessation and alcohol reduction in England. METHODS: Data were used from the Smoking and Alcohol Toolkit Studies, which involve monthly face-to-face computer-assisted interviews of adults aged 16+ in England. We included data collected between June 2014 and July 2015 on 1600 smokers who had made at least one quit attempt and 911 high-risk drinkers (defined as scores >8+ on the full AUDIT or 5+ on questions 1-3 of the AUDIT-C) who had made an attempt to cut down in the past 12 months. Participants provided information on their socio-demographic characteristics and use of aids during their most recent quit attempt including pharmacotherapy, face-to-face counselling, telephone support, self-help materials (digital and printed), and complementary medicine. RESULTS: A total of 60.3% of smokers used aids in the past year, compared with just 14.9% of high-risk drinkers. Use of pharmacotherapy was high among smokers and very low among drinkers (56.0%versus1.2%). Use of other aids was low for both behaviours: face-to-face counselling (2.6%versus4.8%), self-help materials (1.4%versus4.1%) and complementary medicine (1.0%versus0.5%). Use of aids was more common among smokers aged 25-54 compared with 16-24 year olds (25-34,ORadj1.49,p = 0.012; 35-44,ORadj1.93,p 10 relative to 20,ORadj4.23,p = 0.001), and less common among ethnic minorities (ORadj0.69,p = 0.026). For alcohol reduction, use of aids was higher among ethnic minority groups (ORadj2.41;p = 0.015), and those of social-grade D/E relative to AB (ORadj2.29,p = 0.012&ORadj3.13,p < 0.001). CONCLUSION: In England, the use of pharmacotherapy is prevalent for smoking cessation but not alcohol reduction. Other aids are used at a low rate, with face-to-face counselling being more common for alcohol reduction than smoking cessation

    Is the use of e-cigarettes for smoking cessation associated with alcohol consumption? A population-level survey of successful quitters in England

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    Objective: To examine associations between the use of e-cigarettes for smoking cessation and levels of alcohol consumption, high-risk drinking, and attempts to cut down alcohol consumption compared with use of nicotine replacement therapy (NRT) or no aid. Methods: Cross-sectional survey of adults (≥16 years) in England. The sample included a total of 961 people who had quit smoking with the use of either e-cigarettes (n = 425), NRT (n = 116), or no aid (n = 421) within the past year and were still abstinent at the survey. Drinking behaviour was assessed with the AUDIT. Results: Mean (SD) alcohol consumption among those who quit smoking with e-cigarettes, NRT, and no aid was 7.78 (13.41), 7.12 (13.85), and 5.55 (8.70) units/week, respectively. The prevalence of high-risk drinking was 43.3% (n = 184), 32.2% (n = 37), and 36.8% (n = 155), respectively. Among high-risk drinkers, the prevalence of attempts to cut down alcohol consumption was 22.3% (n = 41), 18.9% (n = 7), and 27.7% (n = 43), respectively. After adjustment for covariates, those who quit with e-cigarettes had significantly higher alcohol consumption than those who quit unaided (B = 1.69, 95%CI 0.21–3.17), but there was no significant difference relative to those who quit with NRT. Differences in high-risk drinking and attempts to cut down were not significant, but Bayes factors indicated the data were insensitive (range: 0.47–0.95). Conclusions: Recent ex-smokers who used e-cigarettes to help them quit consumed around two more units of alcohol each week than those who quit unaided, but their alcohol consumption was similar to those who quit with NRT. Data on differences in high-risk drinking and attempts to cut down alcohol consumption among high-risk drinkers were inconclusive

    Predictors of and reasons for attempts to reduce alcohol intake: A population survey of adults in England

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    OBJECTIVE: This study aimed to assess the predictors among high-risk drinkers in England of attempts to reduce alcohol consumption, the reasons given for these attempts and the association between the various reasons and alcohol consumption. METHODS: Data came from 2,800 high-risk drinkers taking part in the Alcohol Toolkit Study (ATS) between March 2014 and November 2016 who were attempting to reduce their alcohol consumption. Participants completed the Alcohol Use Disorders Identification Test (AUDIT) and were asked questions regarding their socio-demographic characteristics, attempts to cut down and reasons for doing so. RESULTS: Those cutting down were significantly older (OR 1.01, p<0.001), were more likely to be female (OR 1.32, p<0.05), had higher AUDIT-C scores (OR 1.12, p<0. 001), were less likely to be of white ethnicity (OR 0.64, p<0. 001), and were more likely to reside in the South of England (OR 1.34, p<0. 001). They were also more likely to be of higher occupationally-based social-grades (p<0. 001). The main reported reasons for reducing consumption were: fitness (22.5%), weight loss (20.4%), future health (20.4%), advice from a health-care professional (7.9%) and cost (7.6%). Those reporting the followings reasons for cutting down had higher AUDIT-C scores than those who did not report these reasons: a concern about further health problems (β 0.20, p<0.05), advice from a doctor/health worker (β 0.38, p<0.05), that drinking was too expensive (β 0.42, p<0.01) and detoxification (β 0.42, p<0.01). Lower AUDIT-C scores were noted among those who reported that they knew someone who was cutting down (β -0.67, p<0.05), that there was no reason (β -0.36, p<0.05), or they didn’t know why they were cutting down (β -0.25, p<0.05). CONCLUSIONS: Around a fifth of high-risk drinkers in England report trying to reduce their drinking, particularly older, high-socioeconomic female drinkers from the south of England. Attempts to cut down appear to be driven by a desire to improve health, advice from others and cutting down on the cost of drinking

    Healthier central England or North-South divide? Analysis of national survey data on smoking and high-risk drinking.

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    OBJECTIVES: This paper compares patterns of smoking and high-risk alcohol use across regions in England, and assesses the impact on these of adjusting for sociodemographic characteristics. DESIGN: Population survey of 53 922 adults in England aged 16+ taking part in the Alcohol and Smoking Toolkit Studies. MEASURES: Participants answered questions regarding their socioeconomic status (SES), gender, age, ethnicity, Government Office Region, smoking status and completed the Alcohol Use Disorders Identification Test (AUDIT). High-risk drinkers were defined as those with a score of 8 or more (7 or more for women) on the AUDIT. RESULTS: In unadjusted analyses, relative to the South West, those in the North of England were more likely to smoke, while those from the East of England, South East and London were less likely. After adjustment for sociodemographics, smoking prevalence was no higher in North East (RR 0.97, p>0.05), North West (RR 0.98, p>0.05) or Yorkshire and the Humber (RR 1.03, p>0.05) but was less common in the East and West Midlands (RR 0.86, p0.05) CONCLUSIONS: In adjusted analyses, smoking and high-risk drinking appear less common in 'central England' than in the rest of the country. Regional differences in smoking, but not those in high-risk drinking, appear to be explained to some extent by sociodemographic disparities
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