2,619 research outputs found

    A spatial disorientation predictor device to enhance pilot situational awareness regarding aircraft attitude

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    An effort was initiated at the Armstrong Aerospace Medical Research Laboratory (AAMRL) to investigate the improvement of the situational awareness of a pilot with respect to his aircraft's spatial orientation. The end product of this study is a device to alert a pilot to potentially disorienting situations. Much like a ground collision avoidance system (GCAS) is used in fighter aircraft to alert the pilot to 'pull up' when dangerous flight paths are predicted, this device warns the pilot to put a higher priority on attention to the orientation instrument. A Kalman filter was developed which estimates the pilot's perceived position and orientation. The input to the Kalman filter consists of two classes of data. The first class of data consists of noise parameters (indicating parameter uncertainty), conflict signals (e.g. vestibular and kinesthetic signal disagreement), and some nonlinear effects. The Kalman filter's perceived estimates are now the sum of both Class 1 data (good information) and Class 2 data (distorted information). When the estimated perceived position or orientation is significantly different from the actual position or orientation, the pilot is alerted

    The effects of acceleration stress on human workload and manual control

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    The effects of +Gz stress on operator task performance and workload were assessed. Subjects were presented a two dimensional maze and were required to solve it as rapidly as possible (by moving a light dot through it via a trim switch on a control stick) while under G-stress at levels from +1 Gz to +6 Gz. The G-stress was provided by a human centrifuge. The effects of this stress were assessed by two techniques; (1) objective performance measures on the primary maze-solving task, and (2) subjective workload measures obtained using the subjective workload assessment technique (SWAT). It was found that while neither moderate (+3 Gz) nor high (+5 Gz and +6 Gz) levels of G-stress affected maze solving performance, the high G levels did increase significantly the subjective workload of the maze task

    Comparison of Allen Carr's Easyway programme with a specialist behavioural and pharmacological smoking cessation support service: a randomized controlled trial.

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    BACKGROUND AND AIMS: A combination of behavioural and pharmacological support is judged to be the optimal approach for assisting smoking cessation. Allen Carr's Easyway (ACE) is a single-session pharmacotherapy-free programme that has been in operation internationally for 38 years. We compared the effectiveness of ACE with specialist behavioural and pharmacological support delivered to the national standard in England. DESIGN: A two-arm, parallel-group, single-blind, randomized controlled trial. SETTING: London, UK, between February 2017 and May 2018. PARTICIPANTS: A total of 620 participants (310 in ACE and 310 in the combined behavioural and pharmacological support condition) were included in the analysis. Adult (≥ 18 years) smokers wanting to quit were randomized in a 1 : 1 ratio. Mean age for the total sample was 40.8 years, with 53.4% being male. Participant baseline characteristics (ethnicity, educational level, number of previous quit attempts, nicotine dependence) were evenly balanced between treatment groups. INTERVENTION AND COMPARATOR: The intervention was the ACE method of stopping smoking. This centres on a 4.5-6-hour session of group-based support, alongside subsequent text messages and top-up sessions if needed. It aims to make it easy to stop smoking by convincing smokers that smoking provides no benefits for them. The comparator was a specialist stop smoking service (SSS) providing behavioural and pharmacological support in accordance with national standards. MEASUREMENTS: The primary outcome was self-reported continuous abstinence for 26 weeks from the quit/quit re-set date verified by exhaled breath carbon monoxide measurement < 10 parts per million (p.p.m.). Primary analysis was by intention to treat. Secondary outcomes were: use of pharmacotherapy, adverse events and continuous abstinence up to 4 and 12 weeks. FINDINGS: A total of 468 participants attended treatment (255 ACE versus 213 SSS, P < 0.05). Of those who did attend treatment, 100 completed 6-month measures (23.7% ACE versus 20.7% SSS). Continuous abstinence to 26 weeks was 19.4% (60 of 310) in the ACE intervention and 14.8% (46 of 310) in the SSS intervention [risk difference for ACE versus SSS 4.5% (95% confidence interval (CI) = -1.4 to 10.4%, odds ratio (OR) = 1.38)]. The Bayes factor for superiority of the ACE condition was 1.24. CONCLUSION: There was no clear evidence of a difference in the efficacies of the Allen Carr's Easyway (ACE) and specialist smoking cessation support involving behavioural support and pharmacotherapy

    Impact of alcohol-promoting and alcohol-warning advertisements on alcohol consumption, affect, and implicit cognition in heavy-drinking young adults: A laboratory-based randomized controlled trial

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    OBJECTIVES\textbf{OBJECTIVES}: There is sparse evidence regarding the effect of alcohol-advertising exposure on alcohol consumption among heavy drinkers. This study aimed to assess the immediate effects of alcohol-promoting and alcohol-warning video advertising on objective alcohol consumption in heavy-drinking young adults, and to examine underlying processes. DESIGN\textbf{DESIGN}: Between-participants randomized controlled trial with three conditions. METHODS\textbf{METHODS}: Two hundred and four young adults (aged 18-25) who self-reported as heavy drinkers were randomized to view one of three sets of 10 video advertisements that included either (1) alcohol-promoting, (2) alcohol-warning, or (3) non-alcohol advertisements. The primary outcome was the proportion of alcoholic beverages consumed in a sham taste test. Affective responses to advertisements, implicit alcohol approach bias, and alcohol attentional bias were assessed as secondary outcomes and possible mediators. Typical alcohol consumption, Internet use, and television use were measured as covariates. RESULTS\textbf{RESULTS}: There was no main effect of condition on alcohol consumption. Participants exposed to alcohol-promoting advertisements showed increased positive affect and an increased approach/reduced avoidance bias towards alcohol relative to those exposed to non-alcohol advertisements. There was an indirect effect of exposure to alcohol-warning advertisements on reduced alcohol consumption via negative affect experienced in response to these advertisements. CONCLUSIONS\textbf{CONCLUSIONS}: Restricting alcohol-promoting advertising could remove a potential influence on positive alcohol-related emotions and cognitions among heavy-drinking young adults. Producing alcohol-warning advertising that generates negative emotion may be an effective strategy to reduce alcohol consumption.This work was jointly funded by the National Institute for Health Research School for Public Health Research, and by the Department of Health Policy Research Program (Policy Research Unit in Behaviour and Health [PR-UN-0409-10109])

    Study protocol for a randomised controlled trial of Allen Carr's Easyway programme versus Lambeth and Southwark NHS for smoking cessation.

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    INTRODUCTION: Smoking is a major cause of ill health and is associated with several diseases including cancer, coronary heart disease and stroke. Many psychological and pharmacological smoking cessation treatments are available and although they are undoubtedly the most cost-effective health interventions available, many people still fail to maintain cessation in the longer term. Recently, National Institute for Health and Care Excellence called for comparative studies to determine the short-term and long-term effectiveness of Allen Carr's Easyway (ACE) method of stopping smoking. This study will compare the efficacy of the ACE programme and a 1-1 counselling service available via the National Health Service. METHODS AND ANALYSIS: A two-arm, parallel-group, blinded, randomised controlled trial will be conducted with people who smoke tobacco cigarettes, are aged ≥18 years and are motivated to quit. Exclusion criteria comprise self-reported mental health condition, pregnancy or respiratory disease such as chronic obstructive pulmonary disease or emphysema. The primary treatment outcome is smoking cessation 26 weeks after treatment. Participants will be analysed on an intention to treat basis at the point of randomisation. Before being randomised, the research team will not inform participants which two treatments are being compared. Once randomised researchers will be blinded to participant condition, and participants will be blinded to the condition they are not assigned to. Logistic regression will be used to estimate the effectiveness of the treatment condition on smoking cessation at 26 weeks. The following covariates will be included: baseline quit efficacy (at inclusion), age (at inclusion), gender and baseline nicotine dependency. ETHICS AND DISSEMINATION: Approval was granted by London-Fulham Research Ethics Committee (ref: 16/LO/1657). The study's findings will be published in peer-reviewed journals and disseminated at national and international conferences. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier number: NCT02855255. ISRCTN registration number: ISRCTN23584477; Pre-results

    Exploring the relationship between sexual compulsivity and attentional bias to sex-related words in a cohort of sexually active individuals

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    Background/Aims: If sexual compulsivity and other addictive behaviours share common aetiology, contemporary proposals about the role of attentional processes in understanding addictive behaviours are relevant. Methods: To examine attentional biases for sex-related words amongst sexually active individuals and the relationship between sexual compulsivity and sexual behavioural engagement with attentional bias, 55 sexually active individuals completed a modified Stroop task and the sexual compulsivity scale. Results: Findings showed attentional bias towards sex-related stimuli among sexually active participants. In addition, amongst those with low levels of sexual compulsivity, levels of attentional bias were the same across all levels of sexual experience. Amongst those with higher levels of sexual compulsivity, greater attentional bias was linked with lower levels of sexual experience. Conclusion: Attentional preference for concern-related stimuli varies as a function of the interaction between how long a person has been active sexually and how compulsive their sexual behaviour is

    The Cleft Care UK study. Part 4:perceptual speech outcomes

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    OBJECTIVES: To describe the perceptual speech outcomes from the Cleft Care UK (CCUK) study and compare them to the 1998 Clinical Standards Advisory Group (CSAG) audit. SETTING AND SAMPLE POPULATION: A cross-sectional study of 248 children born with complete unilateral cleft lip and palate, between 1 April 2005 and 31 March 2007 who underwent speech assessment. MATERIALS AND METHODS: Centre-based specialist speech and language therapists (SLT) took speech audio–video recordings according to nationally agreed guidelines. Two independent listeners undertook the perceptual analysis using the CAPS-A Audit tool. Intra- and inter-rater reliability were tested. RESULTS: For each speech parameter of intelligibility/distinctiveness, hypernasality, palatal/palatalization, backed to velar/uvular, glottal, weak and nasalized consonants, and nasal realizations, there was strong evidence that speech outcomes were better in the CCUK children compared to CSAG children. The parameters which did not show improvement were nasal emission, nasal turbulence, hyponasality and lateral/lateralization. CONCLUSION: These results suggest that centralization of cleft care into high volume centres has resulted in improvements in UK speech outcomes in five-year-olds with unilateral cleft lip and palate. This may be associated with the development of a specialized workforce. Nevertheless, there still remains a group of children with significant difficulties at school entry

    Role of the reversible electrochemical deprotonation of phosphate species in anaerobic biocorrosion of steels

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    Sulphate reducing bacteria are known to play a major role in anaerobic microbiological influenced corrosion of steels, but mechanisms behind their influence are still source of debates as certain phenomena remain unexplained. Some experiments have shown that hydrogen consumption by SRB or hydrogenase increased the corrosion rate of mild steel. This was observed only in the presence of phosphate species. Here the cathodic behaviour of phosphate species on steel was studied to elucidate the role of phosphate in anaerobic corrosion of steel. Results showed: a linear correlation between reduction waves in linear voltammetry and phosphate concentration at a constant pH value; that phosphate ions induced considerable anaerobic corrosion of mild steel, which was sensitive to hydrogen concentration in the solution; and that the corrosion potential of stainless steel in presence of phosphate was shifted to more negative values as molecular hydrogen was added to the atmosphere in the reaction vessel. Phosphate species, and possibly other weak acids present in biofilms, are suggested to play an important role in the anaerobic corrosion of steels via a reversible mechanism of electrochemical deprotonation that may be accelerated by hydrogen removal

    Kinetics and mechanism of organocatalytic aza-Michael additions: direct observation of enamine intermediates.

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    The imidazoles 1a–g add to the CC-double bond of the iminium ion 2 with rate constants as predicted by the equation log k = sN(N + E). Unfavourable proton shifts from the imidazolium unit to the enamine fragment in the adduct 3 account for the failure of imidazoles to take part in iminium-activated aza-Michael additions to enals
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