1,111 research outputs found

    Verbal time estimation in clutterers and non-clutterers

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    Research has suggested that people with fluency disorders, i.e., individuals who stutter, have difficulty with time estimation. A sub-group of fluency disorders are persons who clutter, whose speech is characterized by a rapid and/or irregular rate of speech that is accompanied by excessive disfluencies, abnormally placed pauses, and/or excessive coarticulation. One frequently reported symptom of cluttering is a lack of awareness of one\u27s own cluttering, which may be related to rate deviations. It is possible that persons who clutter may also lack the awareness of the amount of time required to say something, and thus, demonstrate difficulty estimating the amount of time required for an utterance. To test this hypothesis, by pressing a computer mouse button, six adults who clutter and six matched controls estimated the time required to complete 50 self-formulated utterances after given a scenario prompt. An example was Do you prefer cats or dogs and why? Each estimated time was then compared to the actual amount of time required to say the utterance immediately upon releasing the mouse button. Although mean statistical differences did not differentiate cluttering and control groups, both groups overestimated time in general, and clutterers demonstrated a trend of overestimating more than controls. Individual cluttering-control pair differences revealed trends suggesting that two-thirds of each group overestimated speaking time, one-sixth underestimated speaking time, and the remaining one-sixth estimated speaking time fairly accurately. Additionally, participants who clutter had more variability in their estimated times when compared to controls, while actual times were more similar. These trends suggest that individuals who clutter have some disruption in their ability to estimate time. This may be caused by an internal time clock that is disrupted in some way, or due to an increase in time required to form an utterance

    Semiconductor-metal nanoparticle molecules: hybrid excitons and non-linear Fano effect

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    Modern nanotechnology opens the possibility of combining nanocrystals of various materials with very different characteristics in one superstructure. The resultant superstructure may provide new physical properties not encountered in homogeneous systems. Here we study theoretically the optical properties of hybrid molecules composed of semiconductor and metal nanoparticles. Excitons and plasmons in such a hybrid molecule become strongly coupled and demonstrate novel properties. At low incident light intensity, the exciton peak in the absorption spectrum is broadened and shifted due to incoherent and coherent interactions between metal and semiconductor nanoparticles. At high light intensity, the absorption spectrum demonstrates a surprising, strongly asymmetric shape. This shape originates from the coherent inter-nanoparticle Coulomb interaction and can be viewed as a non-linear Fano effect which is quite different from the usual linear Fano resonance.Comment: 5 pages, 5 figures, submitted to Phys. Rev. Let

    Trends in Concurrency, Polygyny, and Multiple Sex Partnerships During a Decade of Declining HIV Prevalence in Eastern Zimbabwe.

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    Background. Observed declines in the prevalence of human immunodeficiency virus (HIV) infection in Zimbabwe have been attributed to population-level reductions in sexual partnership numbers. However, it remains unknown whether certain types of sex partnerships were more important to this decline. Particular debate surrounds the epidemiologic importance of polygyny (the practice of having multiple wives). Methods. We analyze changes in reported multiple partnerships, nonmarital concurrency, and polygyny in eastern Zimbabwe during a period of declining HIV prevalence, from 1998 to 2011. Trends are reported for adult men (age, 17–54 years) and women (age, 15–49 years) from 5 survey rounds of the Manicaland HIV/STD Prevention Project, a general-population open cohort study. Results. At baseline, 34.2% of men reported multiple partnerships, 11.9% reported nonmarital concurrency, and 4.6% reported polygyny. Among women, 4.6% and 1.8% reported multiple partnerships and concurrency, respectively. All 3 partnership indicators declined by similar relative amounts (around 60%–70%) over the period. Polygyny accounted for around 25% of male concurrency. Compared with monogamously married men, polygynous men reported higher levels of subsequent divorce/separation (adjusted relative risk [RR], 2.92; 95% confidence interval [CI], 1.87–4.55) and casual sex partnerships (adjusted RR, 1.63; 95% CI, 1.41–1.88). Conclusions. No indicator clearly dominated declines in partnerships. Polygyny was surprisingly unstable and, in this population, should not be considered a safe form of concurrency

    Anomalous morphology in left hemisphere motor and premotor cortex of children who stutter

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    Stuttering is a neurodevelopmental disorder that affects the smooth flow of speech production. Stuttering onset occurs during a dynamic period of development when children first start learning to formulate sentences. Although most children grow out of stuttering naturally, ∼1% of all children develop persistent stuttering that can lead to significant psychosocial consequences throughout one’s life. To date, few studies have examined neural bases of stuttering in children who stutter, and even fewer have examined the basis for natural recovery versus persistence of stuttering. Here we report the first study to conduct surface-based analysis of the brain morphometric measures in children who stutter. We used FreeSurfer to extract cortical size and shape measures from structural MRI scans collected from the initial year of a longitudinal study involving 70 children (36 stuttering, 34 controls) in the 3–10-year range. The stuttering group was further divided into two groups: persistent and recovered, based on their later longitudinal visits that allowed determination of their eventual clinical outcome. A region of interest analysis that focused on the left hemisphere speech network and a whole-brain exploratory analysis were conducted to examine group differences and group × age interaction effects. We found that the persistent group could be differentiated from the control and recovered groups by reduced cortical thickness in left motor and lateral premotor cortical regions. The recovered group showed an age-related decrease in local gyrification in the left medial premotor cortex (supplementary motor area and and pre-supplementary motor area). These results provide strong evidence of a primary deficit in the left hemisphere speech network, specifically involving lateral premotor cortex and primary motor cortex, in persistent developmental stuttering. Results further point to a possible compensatory mechanism involving left medial premotor cortex in those who recover from childhood stuttering.This study was supported by Award Numbers R01DC011277 (SC) and R01DC007683 (FG) from the National Institute on Deafness and other Communication Disorders (NIDCD). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIDCD or the National Institutes of Health. (R01DC011277 - National Institute on Deafness and other Communication Disorders (NIDCD); R01DC007683 - National Institute on Deafness and other Communication Disorders (NIDCD))Accepted manuscrip

    Associations between smoking status and bodily pain in a cross-sectional survey of UK respondents

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    BACKGROUND: Research indicates that ex- and current smokers report increased levels of bodily pain compared with never smokers. This could be secondary to smoking-related disease or psychological characteristics of smokers, or it could be a neurological or vascular effect of a period of regular smoking. AIMS: We compared self-reported levels of bodily pain in daily, never daily and former daily smokers stratified by age group and adjusting for a wider range of covariates than has been undertaken to-date, including health status, neuroticism, anxiety and depression. METHOD: 223,537 UK respondents aged 16+ years were surveyed between 2009 and 2013 in the British Broadcasting Corporation (BBC) Lab UK Study. Respondents provided information on bodily pain, smoking status and a range of sociodemographic, health, behavioural and psychological characteristics. RESULTS: After adjusting for all covariates, in 16-34-year-olds, reported levels of bodily pain in former daily smokers (B_{adj} = 0.72, 95% CI = 0.30, 1.15, p < .001) and daily smokers (B_{adj} = 0.50, 95% CI = 0.18, 0.82, p < .01) were higher than in never daily smokers. Reported levels of bodily pain were also higher in former daily smokers than in never daily smokers in those aged 35–64 (B_{adj} = 1.04, 95% CI = 0.69, 1.38, p < .001) and 65 + years (B_{adj} = 1.65, 95% CI = 0.07, 3.24, p < .05). CONCLUSIONS: After adjusting for key characteristics, former daily smokers reported higher levels of bodily pain compared with never daily smokers at all ages. This raises the possibility that a period of smoking may have lasting effects on pain experiences

    Trends in and factors associated with the adoption of digital aids for smoking cessation and alcohol reduction: A population survey in England

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    Background: Digital smoking cessation and alcohol reduction aids are widely available in England. To estimate their public health impact, researchers need to consider their adoption in the target population. We assessed adoption rates, and characteristics of adopters, of digital smoking cessation and alcohol reduction aids in England. Methods: 3655 smokers and 2998 high-risk drinkers (defined as a score of >4 on the Alcohol Use Disorders Identification Test-Consumption; AUDIT-C) who had made a past-year quit/reduction attempt were surveyed as part of the Smoking and Alcohol Toolkit Studies between January 2015-October 2018. Respondents provided information on socio-demographic characteristics and whether they had used a digital aid in a recent quit/reduction attempt. Results: 2.7 % (95 % CI 2.2%–3.0%) of smokers and 3.6 % (95 % CI 2.9%–4.0%) of drinkers who had made a past-year quit/reduction attempt (26.9 % and 15.3 %, respectively) had used a digital aid. Survey year was not significantly associated with use in smokers or drinkers. None of the baseline characteristics were significantly associated with the use of a digital aid in smokers. Drinkers with high motivation to reduce alcohol consumption (ORadj = 2.49, 95 % CI 1.63–3.77, p <  .001) and higher AUDIT scores (ORadj = 1.07, 95 % CI 1.03–1.11, p < .001) had greater odds of adoption. Conclusions: Digital smoking cessation and alcohol reduction aids are rarely used by smokers or high-risk drinkers attempting to quit/cut down in England, indicating that most of the target population is not being reached. Despite overall digital access improving, adoption rates remained similarly low between 2015–2018

    Engagement With a Behavior Change App for Alcohol Reduction: Data Visualization for Longitudinal Observational Study

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    BACKGROUND: Behavior change apps can develop iteratively, where the app evolves into a complex, dynamic, or personalized intervention through cycles of research, development, and implementation. Understanding how existing users engage with an app (eg, frequency, amount, depth, and duration of use) can help guide further incremental improvements. We aim to explore how simple visualizations can provide a good understanding of temporal patterns of engagement, as usage data are often longitudinal and rich. OBJECTIVE: This study aims to visualize behavioral engagement with Drink Less, a behavior change app to help reduce hazardous and harmful alcohol consumption in the general adult population of the United Kingdom. METHODS: We explored behavioral engagement among 19,233 existing users of Drink Less. Users were included in the sample if they were from the United Kingdom; were 18 years or older; were interested in reducing their alcohol consumption; had a baseline Alcohol Use Disorders Identification Test score of 8 or above, indicative of excessive drinking; and had downloaded the app between May 17, 2017, and January 22, 2019 (615 days). Measures of when sessions begin, length of sessions, time to disengagement, and patterns of use were visualized with heat maps, timeline plots, k-modes clustering analyses, and Kaplan-Meier plots. RESULTS: The daily 11 AM notification is strongly associated with a change in engagement in the following hour; reduction in behavioral engagement over time, with 50.00% (9617/19,233) of users disengaging (defined as no use for 7 or more consecutive days) 22 days after download; identification of 3 distinct trajectories of use, namely engagers (4651/19,233, 24.18% of users), slow disengagers (3679/19,233, 19.13% of users), and fast disengagers (10,903/19,233, 56.68% of users); and limited depth of engagement with 85.076% (7,095,348/8,340,005) of screen views occurring within the Self-monitoring and Feedback module. In addition, a peak of both frequency and amount of time spent per session was observed in the evenings. CONCLUSIONS: Visualizations play an important role in understanding engagement with behavior change apps. Here, we discuss how simple visualizations helped identify important patterns of engagement with Drink Less. Our visualizations of behavioral engagement suggest that the daily notification substantially impacts engagement. Furthermore, the visualizations suggest that a fixed notification policy can be effective for maintaining engagement for some users but ineffective for others. We conclude that optimizing the notification policy to target both effectiveness and engagement is a worthwhile investment. Our future goal is to both understand the causal effect of the notification on engagement and further optimize the notification policy within Drink Less by tailoring to contextual circumstances of individuals over time. Such tailoring will be informed from the findings of our micro-randomized trial (MRT), and these visualizations were useful in both gaining a better understanding of engagement and designing the MRT

    Do daily fluctuations in psychological and app-related variables predict engagement with an alcohol reduction app? A series of N-of-1 studies

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    Background: Previous studies have identified psychological and smartphone app-related predictors of engagement with alcohol reduction apps at a group level. However, strategies to promote engagement need to be effective at the individual level. Evidence as to whether group-level predictors of engagement are also predictive for individuals is lacking. Objective: This study aimed to examine whether daily fluctuations in: i) the receipt of a reminder, ii) motivation to reduce alcohol, iii) perceived usefulness of the app, iv) alcohol consumption, and v) perceived lack of time predicted within-person variability in the frequency and amount of engagement with an alcohol reduction app. Methods: A series of observational N-of-1 studies were conducted. The predictor variables were measured twice daily for 28 days via Ecological Momentary Assessments. The outcome variables were measured through automated recordings of participants’ app screen views. Nine London-based adults who drank alcohol excessively and were willing to set a reduction goal took part. Each participant’s dataset was analysed separately using Generalised Additive Mixed Models to derive incidence rate ratios (IRRs) for the within-person associations of the predictor and outcome variables. Debriefing interviews, analysed using thematic analysis, were used to contextualise the findings. Results: Predictors of the frequency and amount of engagement differed between individuals, and for the variables ‘perceived usefulness of the app’ and ‘perceived lack of time’, the direction of associations also differed between individuals. The most consistent predictors of within-person variability in the frequency of engagement were the receipt of a daily reminder (IRRs = 1.80-3.88, P’s < .05) and perceived usefulness of the app (IRRs = 0.82-1.42, P’s < .05). The most consistent predictors of within-person variability in the amount of engagement were motivation to reduce alcohol (IRRs = 1.67-3.45, P’s < .05) and perceived usefulness of the app (IRRs = 0.52-137.32, P’s < .05). Conclusions: The utility of the selected psychological and app-related variables in predicting the frequency and amount of engagement with an alcohol reduction app differed at the individual level. This highlights that key within-person associations may be masked in group-level designs and suggests that different strategies to promote engagement may be required for different individuals. Clinical Trial: osf.io/zn79
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