258 research outputs found

    A Boltzmann model for rod alignment and schooling fish

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    We consider a Boltzmann model introduced by Bertin, Droz and Greegoire as a binary interaction model of the Vicsek alignment interaction. This model considers particles lying on the circle. Pairs of particles interact by trying to reach their mid-point (on the circle) up to some noise. We study the equilibria of this Boltzmann model and we rigorously show the existence of a pitchfork bifurcation when a parameter measuring the inverse of the noise intensity crosses a critical threshold. The analysis is carried over rigorously when there are only finitely many non-zero Fourier modes of the noise distribution. In this case, we can show that the critical exponent of the bifurcation is exactly 1/2. In the case of an infinite number of non-zero Fourier modes, a similar behavior can be formally obtained thanks to a method relying on integer partitions first proposed by Ben-Naim and Krapivsky.Comment: 22 pages, 3 figure

    Television viewing and low leisure-time physical activity in adolescence independently predict the metabolic syndrome in mid-adulthood

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    Objective: We investigated whether television (TV) viewing and low leisure-time physical activity in adolescence predict the metabolic syndrome in mid-adulthood. Research design and methods: TV viewing habits and participation in leisure-time physical activity at age 16 years were assessed by self-administered questionnaires in a population-based cohort in Northern Sweden. The presence of the metabolic syndrome at age 43 years was ascertained in 888 participants (82% of the baseline sample) using the International Diabetes Federation criteria. Odds ratios (ORs) and CIs were calculated using logistic regression. Results: The overall prevalence of the metabolic syndrome at age 43 years was 26.9%. Adjusted OR for the metabolic syndrome at age 43 years was 2.14 (95% CI 1.24–3.71) for those who reported “watching several shows a day” versus “one show/week” or less and 2.31 (1.13–4.69) for leisure-time physical activity “several times/month” or less compared with “daily” leisure-time physical activity at age 16 years. TV viewing at age 16 years was associated with central obesity, low HDL cholesterol, and hypertension at age 43 years, whereas low leisure-time physical activity at age 16 years was associated with central obesity and triglycerides at age 43 years. Conclusions: Both TV viewing and low leisure-time physical activity in adolescence independently predicted the metabolic syndrome and several of the metabolic syndrome components in mid-adulthood. These findings suggest that reduced TV viewing in adolescence, in addition to regular physical activity, may contribute to cardiometabolic health later in life

    Fish Consumption and Ischemic stroke in Southern Sweden

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    <p>Abstract</p> <p>Background</p> <p>The relationship between fish intake and stroke incidence has been inconsistent in previous Swedish studies. Here, we report the risk of stroke and fish intake in a cohort from southern Sweden.</p> <p>Findings</p> <p>Data were obtained from an already available population based case-control study where the cases were defined as incident first-time ischemic stroke patients. Complete data on all relevant variables were obtained for 2722 controls and 2469 cases. The data were analyzed with logistic regression analysis. Stroke risk decreased with fat fish intake ([greater than or equal to] 1/week versus <1/month) in both men and women; adjusted pooled Odds Ratio (OR) 0.69, 95% Confidence Interval (CI): 0.54-0.89. However, stroke risk for women increased with intake of lean fish; adjusted OR 1.63 (95% CI: 1.17-2.28), whereas there was no association with men's lean fish intake; adjusted OR 0.97(95% CI: 0.73-1.27). Fish intake was self-reported retrospectively, yielding uncertain exposure assessment and potential recall bias. The findings regarding lean fish could be explained by recall bias if an individual's inclination to report lean fish consumption depended on both disease status and sex. The fact that the association between fat fish intake and stroke was similar in men and women does not support such a differential in recall.</p> <p>Conclusions</p> <p>The results suggest fat fish intake to decrease ischemic stroke risk and lean fish intake to increase women's stroke risk. The inconsistent relationship between fish intake and stroke risk reported in previous studies is further stressed by the results of this study.</p

    On Strong Convergence to Equilibrium for the Boltzmann Equation with Soft Potentials

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    The paper concerns L1L^1- convergence to equilibrium for weak solutions of the spatially homogeneous Boltzmann Equation for soft potentials (-4\le \gm<0), with and without angular cutoff. We prove the time-averaged L1L^1-convergence to equilibrium for all weak solutions whose initial data have finite entropy and finite moments up to order greater than 2+|\gm|. For the usual L1L^1-convergence we prove that the convergence rate can be controlled from below by the initial energy tails, and hence, for initial data with long energy tails, the convergence can be arbitrarily slow. We also show that under the integrable angular cutoff on the collision kernel with -1\le \gm<0, there are algebraic upper and lower bounds on the rate of L1L^1-convergence to equilibrium. Our methods of proof are based on entropy inequalities and moment estimates.Comment: This version contains a strengthened theorem 3, on rate of convergence, considerably relaxing the hypotheses on the initial data, and introducing a new method for avoiding use of poitwise lower bounds in applications of entropy production to convergence problem

    Reducing occupational sitting time in adults with type 2 diabetes: Qualitative experiences of an office-adapted mHealth intervention.

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    AIM: Understanding barriers and facilitators for limiting occupational sitting and what impact it has on health on those with type 2 diabetes is essential for future trials and intervention development in primary healthcare settings. This study aimed to explore the feasibility and acceptability of an intervention using mobile health (mHealth) technology, together with counselling by a diabetes specialist nurse, to reduce occupational sitting in adults with type 2 diabetes. METHODS: Individual semi-structured interviews were conducted in 15 participants with type 2 diabetes who completed a 3-month intervention including mHealth; activity tracker (Garmin Vivofit3) and SMS reminders, one initial face-to-face patient-centred counselling session and three telephone follow-up calls by a diabetes specialist nurse within the primary healthcare system in Sweden. The interviews were recorded, transcribed verbatim and analysed using qualitative content analysis. RESULTS: Two themes were identified: (1) 'From baby steps to milestones' reflecting three categories; 'Small changes make it easier to reduce sitting', 'Encouraged by trustworthy coaching', 'Physical and mental rewards matter' and (2) 'Tailoring strategies that fit me and my workplace' reflecting four categories; 'It's up to me', 'Taking advantage of the support', 'Using creativity to find practical solutions for interrupting sitting' and 'Living up to expectations'. CONCLUSION: The intervention was perceived as feasible and acceptable in different office workplaces, and led to increased awareness of sedentary behaviour in adults with type 2 diabetes. Stepwise goal setting together with personalization of the mHealth intervention should be emphasized in individual type 2 diabetes programmes aiming to reduce workplace sitting

    Nurse educator competence in four European countries—A comparative cross-sectional study

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    Abstract Aim The aim of this article is to describe and compare the nurse educator competences in four European countries using three different evaluators: nurse educators (n = 329), heads of a nursing subject (n = 60) and student nurses (n = 1058). Design The study was conducted as a comparative cross‐sectional survey in Finland, Malta, Slovakia and Spain between May 2021 and February 2022. Methods The data were collected with an online survey. The instrument used was a 20‐item Tool for Evaluation of Requirements of Nurse Teachers, utilizing a 5‐point Likert‐type scale. The data were analysed statistically and reported according to STROBE guidelines. Results Nurse educators' competence evaluated positively in all the groups of evaluators, with a mean of >3.5. The self‐evaluation of nurse educators' competence was higher than the other evaluators' evaluations. Having a degree in nursing, having completed some pedagogical studies and longer work experience as a nurse educator had a positive association with higher self‐evaluated competence among nurse educators. Conclusions Nurse educator competence is at a good level in the selected European countries, but further studies are required to find the reasons behind the differences in evaluations. Public Contribution Each participating educational institution named a contact person who distributed the surveys to the participants and returned the study's metadata to the researchers

    Overview of ongoing cohort and dietary studies in the Arctic

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    Published version. Source at http://dx.doi.org/10.3402/ijch.v75.33803 This article gives an overview of the ongoing cohort and dietary studies underlying the assessment of population health in the Arctic. The emphasis here is on a description of the material, methods and results or preliminary results for each study. Detailed exposure information is available in an article in this journal, whereas another paper describes the effects associated with contaminant exposure in the Arctic. The cohort descriptions have been arranged geographically, beginning in Norway and moving east to Finland, Sweden, Russia and the other Arctic countries and ultimately to the Faroe Islands. No cohort studies have been reported for Alaska or Iceland

    Variability of adenoidectomy/tonsillectomy rates among children of the Veneto Region, Italy

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    <p>Abstract</p> <p>Background</p> <p>Despite national guidelines in 2003 aimed at limiting the recourse to tonsillectomy and/or adenoidectomy (A/T), the latter are among the most frequent pediatric surgeries performed in Italy. Aim of the study is to investigate variability of A/T rates among children of the Veneto Region, Italy.</p> <p>Methods</p> <p>All discharges of Veneto residents with Diagnosis-Related Groups 57–60 and ICD9-CM intervention codes 28.2 (tonsillectomy), 28.3 (adenotonsillectomy), 28.6 (adenoidectomy) were selected in the period 2000–2006 for a descriptive analysis. A multilevel Poisson regression model was applied to estimate Incidence Rate Ratios (IRR) with 95% Confidence Intervals (CI) for A/T surgery among children aged 2–9 years in 2004–2006, while taking into account clustering of interventions within the 21 Local Health Units.</p> <p>Results</p> <p>Through 2000–2006, the overall number of A/T surgeries decreased (-8%); there was a decline of adenoidectomies (-20%) and tonsillectomies (-8%), whereas adenotonsillectomies raised (+18%). Analyses on children aged 2–9 resulted in an overall rate of 14.4 surgeries per 1000 person-years (16.1 among males and 12.5 among females), with a wide heterogeneity across Local Health Units (range 8.1–27.6). At random intercept Poisson regression, while adjusting for sex and age, intervention rates were markedly lower among foreign than among Italian children (IRR = 0.57, CI 0.53–0.61). A/T rates in the 10–40 age group (mainly tonsillectomies) computed for each Local Health Unit and introduced in the regression model accounted for 40% of the variance at Local Health Unit level of pediatric rates (mainly adenoidectomies and adenotonsillectomies).</p> <p>Conclusion</p> <p>A/T rates in the Veneto Region, especially adenoidectomies among children aged 2–9 years, remain high notwithstanding a decrease through 2000–2006. A wide heterogeneity according to nationality and Local Health Units is evident. The propensity to A/T surgery of each Local Health Unit is similar in different age groups and for different surgical indications.</p

    El desarrollo del liderazgo a través de un congreso organizado por estudiantes. Estudio pre-post intervención

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    [EN] A Student led Conference, planned and organized by nursing students enrolled in two elective modules (Interdisciplinary Care of Older Adults and Old Age and Dependency) across two academic years (2018-19 and 2019-20). Students participate actively in the conference, with oral communications (as part of their course assignment), or moderating a rounded table. The results shown a significative increase of the level of leadership in the students that led the conference, and a high level of satisfaction in the participants in the conference. This innovative teaching method, may be of intereset and applied in different ambits, as it is necessary to implement methodologies that help to develop competences as leadership and communication.[ES] Presentamos una Student Led Conference planificada y organizada por estudiantes de enfermería matriculados en dos asignaturas optativas (Abordaje Interdisciplinar al Anciano y Ancianidad y Dependencia). Los estudiantes también participaron activamente en el congreso, presentando comunicaciones orales (como parte de la evaluación de la asignatura), o moderando una mesa redonda. Los resultados muestran un incremento significativo del nivel de liderazgo en los estudiantes que organizaron el congreso, así como un alto nivel de satisfacción en los participantes en el mismo. Este método docente innovador, puede ser de interés y aplicado en numerosos ámbitos, ya que es necesario implementar metodologías que ayuden a desarrollar competencias como liderazgo y comunicación.De Juan Pardo, M.; Fuster-Linares, P.; Gallart Fernández-Puebla, A.; Rodriguez, E.; Wennberg, L.; Martín-Ferreres, M. (2021). El desarrollo del liderazgo a través de un congreso organizado por estudiantes. Estudio pre-post intervención. En IN-RED 2021: VII Congreso de Innovación Edicativa y Docencia en Red. Editorial Universitat Politècnica de València. 1533-1539. https://doi.org/10.4995/INRED2021.2021.13780OCS1533153
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