346 research outputs found

    Cooling of a suspended nanowire by an AC Josephson current flow

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    We consider a nanoelectromechanical Josephson junction, where a suspended nanowire serves as a superconducting weak link, and show that an applied DC bias voltage an result in suppression of the flexural vibrations of the wire. This cooling effect is achieved through the transfer of vibronic energy quanta first to voltage driven Andreev states and then to extended quasiparticle electronic states. Our analysis, which is performed for a nanowire in the form of a metallic carbon nanotube and in the framework of the density matrix formalism, shows that such self-cooling is possible down to a level where the average occupation number of the lowest flexural vibration mode of the nanowire is 0.1\sim 0.1.Comment: 4 pages, 3 figure

    Voltage-driven superconducting weak link as a refrigerator for cooling of nanomechanical vibrations

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    We consider a new type of cooling mechanism for a suspended nanowire acting as a weak link between two superconductive electrodes. By applying a bias voltage over the system, we show that the system can be viewed as a refrigerator for the nanomechanical vibrations, where energy is continuously transferred from the vibrational degrees of freedom to the extended quasiparticle states in the leads through the periodic modulation of the inter-Andreev level separation. The necessary coupling between the electronic and mechanical degrees of freedom responsible for this energy-transfer can be achieved both with an external magnetic or electrical field, and is shown to lead to an effective cooling of the vibrating nanowire. Using realistic parameters for a suspended nanowire in the form of a metallic carbon nanotube we analyze the evolution of the density matrix and demonstrate the possibility to cool the system down to a stationary vibron population of 0.1\sim 0.1. Furthermore, it is shown that the stationary occupancy of the vibrational modes of the nanowire can be directly probed from the DC current responsible for carrying away the absorbed energy from the vibrating nanowire.Comment: 10 pages, 4 figure

    Dynamics of a suspended nanowire driven by an ac Josephson current in an inhomogeneous magnetic field

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    We consider a voltage-biased nanoelectromechanical Josephson junction, where a suspended nanowire forms a superconducting weak-link, in an inhomogeneous magnetic field. We show that a nonlinear coupling between the Josephson current and the magnetic field generates a Laplace force that induces a whirling motion of the nanowire. By performing an analytical and a numerical analysis, we demonstrate that at resonance, the amplitude-phase dynamics of the whirling movement present different regimes depending on the degree of inhomogeneity of the magnetic field: time independent, periodic and chaotic. Transitions between these regimes are also discussed.Comment: 7 pages, 5 figure

    CLOCK 3111 T/C SNP Interacts with Emotional Eating Behavior for Weight-Loss in a Mediterranean Population

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    Objective: The goals of this research was (1) to analyze the role of emotional eating behavior on weight-loss progression during a 30-week weight-loss program in 1,272 individuals from a large Mediterranean population and (2) to test for interaction between CLOCK 3111 T/C SNP and emotional eating behavior on the effectiveness of the weight-loss program. Design and Methods: A total of 1,272 overweight and obese participants (BMI: 31±5 kg/m2), aged 20 to 65 years, attending outpatient weight-loss clinics were recruited for this analysis. Emotional eating behavior was assessed by the Emotional Eating Questionnaire (EEQ), a questionnaire validated for overweight and obese Spanish subjects. Anthropometric measures, dietary intake and weight-loss progression were assessed and analyzed throughout the 30-week program. Multivariate analysis and linear regression models were performed to test for gene-environment interaction. Results: Weight-loss progression during the 30-week program differed significantly according to the degree of emotional eating behavior. Participants classified as 'very emotional eaters' experienced more irregular (P = 0.007) weight-loss, with a lower rate of weight decline (−0.002 vs. −0.003, P = 11), lost significantly less weight than those C carriers with a low emotional score (<11) (P = 0.005). Conclusions: Emotional eating behavior associates with weight-loss pattern, progression and total weight-loss. Additionally, CLOCK 3111 T/C SNP interacts with emotional eating behavior to modulate total weight loss. These results suggest that the assessment of this locus and emotional eating behavior could improve the development of effective, long-tern weight-management interventions

    Validation of a questionnaire on emotional eating for use in cases of obesity : the Emotional Eater Questionnaire (EEQ)

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    Introduction: Emotions have a powerful effect on our choice of food and eating habits. It has been found that in some people there is relationship between eating, emotions and the increased energy intake. This relationship should be measurable to better understand how food is used to deal with certain mood states and how these emotions affect the effectiveness of weight loss programs. Objective: To develop and analyze the psychometric characteristics of a questionnaire on emotional eating for obesity easy to apply in clinical practice. Subjects and methods: A ten-item questionnaire called Emotional-Eater-Questionnaire (EEQ) was developed and administered to a total of 354 subjects (body mass index, 31 ± 5), aged 39 ± 12, who were subjected to a weight-reduction program. The questionnaire was specifically designed for obesity. Analysis of the internal structure, internal consistency, test-retest reliability and convergent validity with Mindful-Eater-Questionnaire (MEQ) were conducted. Results: After principal components analysis, the questionnaire was classified in three different dimensions that explained 60% of the total variance: Disinhibition, Type-of-food and Guilt. Internal consistency showed that Cronbach's alpha was 0.773 for the "Dishinibition" subscale, 0.656 for the "Type of food" subscale and 0.612 for the "Guilt" subscale. The test-retest stability was r =0.70. The data showed that the percentage of agreement between the EEQ and the MEQ was around 70% with a Kappa index of 0.40; P < 0.0001. Conclusion: We have presented a new questionnaire, which classifies individuals as a function of the relation between food intake and emotions. Such information will permit personalised treatments to be designed by drawing up early strategies from the very beginning of treatment programmesIntroducción: Las emociones tienen un poderoso efecto sobre la elección de alimentos y los hábitos alimentarios. Existe una relación entre comer, emociones y el aumento del aporte calórico. Esta relación debería ser medible para comprender mejor cómo utilizamos los alimentos en determinados estados de ánimo y cómo las emociones afectan a la eficacia de los programas de pérdida de peso. Objetivo: Desarrollar y analizar las características psicométricas de un cuestionario para identificar la ingesta emocional en la obesidad de fácil aplicación en la práctica clínica. Material y métodos: Se ha desarrollado y administrado un cuestionario de diez ítems llamado Cuestionario-de-Comedor-Emocional (CCE) a un total de 354 sujetos (Índice de Masa Corporal: 31 ± 5), (Edad: 39 ± 12 años), pertenecientes a un programa de reducción de peso. Se llevó a cabo un análisis de la estructura interna del cuestionario, de la consistencia interna, la fiabilidad testretest y la validez convergente con el Mindful-Eater- Questionnaire (MEQ). Resultados: El análisis de componentes principales del cuestionario encontró tres dimensiones diferentes que explicaban el 60% de la varianza: desinhibición, tipo de alimento y culpa. La consistencia interna mostró que el alfa de Cronbach fue de 0,773 para la subescala "Desinhibición", 0,656 para "Tipo de alimentos" y 0,612 para "culpa". La estabilidad test-retest fue de r = 0,70. Los datos mostraron que el porcentaje de acuerdo entre el CCE y MEQ era del 70% con un índice Kappa de 0,40, P < 0,0001. Conclusión: Hemos presentado un nuevo cuestionario, que clasifica a los individuos en función de la relación entre la ingesta de alimentos y las emociones. Esta información permitirá el diseño de tratamientos personalizados desde el inicio para la obesida

    Proceedings From the Symposium on Kidney Disease in Older People: Royal Society of Medicine, London, January 19, 2017

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    People are living longer. On the whole, they have healthier lives and many of the problems previously seen at a younger age now appear in their later years. Kidneys, like other organs, age, and kidney disease in the aged is a prime example. In the United Kingdom, as in other developed countries, the prevalence of end stage kidney disease is highest in the 70- to 79-year-old age group. There are many older people who require renal replacement and are now considered for dialysis. While older patients with end-stage renal disease invariably aspire for a better quality of life, this needs a specialized approach and management. In January 2017, the Royal Society of Medicine held a seminar in London on “Kidney Disease in Older People” with presentations from a multidisciplinary body of experts speaking on various aspects of kidney problems in this age group and its management. The objectives were to increase awareness and improve the understanding of nephrology in the context of geriatric medicine but also geriatrics in its interface with nephrology, especially in the area of chronic kidney disease

    Adherence to chronic medication in older populations: application of a common protocol among three European cohorts

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    Purpose: The purpose of this study was to evaluate and compare medication adherence to chronic therapies in older populations across different regions in Europe. Methods: This explorative study applied a harmonized method of data extraction and analysis from pharmacy claims databases of three European countries to compare medication adherence at a cross-country level. Data were obtained for the period between January 1, 2010, and December 31, 2011. Patients (aged >= 65 years) who newly initiated to oral antidiabetics, antihyperlipidemics, or antiosteoporotics were identified and followed for over a 12-month period. Main outcome measures were medication adherence (medication possession ratio, [MPR]; implementation) and persistence on index treatment. All country-specific data sets were prepared by employing a common data input model. Outcome measures were calculated for each country and pooled using random effect models. Results: In total, 39, 186 new users were analyzed. In pooled data from the three countries, suboptimal implementation (MPR <80%) was 52.45% (95% CI: 33.43-70.79) for antihyperlipidemics, 61.35% (95% CI: 52.83-69.22) for antiosteoporotics, and 30.33% (95% CI: 25.53-35.60) for oral antidiabetics. Similarly, rates of non-persistence (discontinuation) were 55.63% (95% CI: 35.24-74.29) for antihyperlipidemics, 60.24% (95% CI: 45.35-73.46) for antiosteoporotics, and 46.80% (95% CI: 36.40-57.4) for oral antidiabetics. Conclusion: Medication adherence was suboptimal with >50% of older people non-adherent to antihyperlipidemics and antiosteoporotics in the three European cohorts. However, the degree of variability in adherence rates among the three countries was high. A harmonized method of data extraction and analysis across health-related database in Europe is useful to compare medication-taking behavior at a cross-country level

    Initial therapy, regimen change, and persistence in a spanish cohort of newly treated type 2 diabetes patients: A retrospective, observational study using real-world data

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    The World Health Organization considers the non-adherence to medication a significant issue with global impact, especially in chronic conditions such as type 2 diabetes. We aim to study antidiabetic treatment initiation, add-on, treatment switching, and medication persistence. We conducted an observational study on 4247 individuals initiating antidiabetic treatment between 2013 and 2014 in the EpiChron Cohort (Spain). We used Cox regression models to estimate the likelihood of non-persistence after a one-year follow-up, expressed as hazard ratios (HRs). Metformin was the most frequently used first-line antidiabetic (80% of cases); combination treatment was the second most common treatment in adults aged 40–79 years, while dipeptidyl peptidase-4 inhibitors were the second most common in individuals in their 80s and over, and in patients with renal disease. Individuals initiated on metformin were less likely to present addition and switching events compared with any other antidiabetic. Almost 70% of individuals initiated on monotherapy were persistent. Subjects aged 40 and over (HR 0.53–0.63), living in rural (HR 0.79) or more deprived areas (HR 0.77–0.82), or receiving polypharmacy (HR 0.84), were less likely to show discontinuation. Our findings could help identify the population at risk of discontinuation, and offer them closer monitoring for proper integrated management to improve prognosis and health outcomes

    Changes in multimorbidity and polypharmacy patterns in young and adult population over a 4-year period: A 2011–2015 comparison using real-world data

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    The pressing problem of multimorbidity and polypharmacy is aggravated by the lack of specific care models for this population. We aimed to investigate the evolution of multimorbidity and polypharmacy patterns in a given population over a 4-year period (2011–2015). A cross-sectional, observational study among the EpiChron Cohort, including anonymized demographic, clinical and drug dispensation information of all users of the public health system ≥65 years in Aragon (Spain), was performed. An exploratory factor analysis, stratified by age and sex, using an open cohort was carried out based on the tetra-choric correlations among chronic diseases and dispensed drugs during 2011 and compared with 2015. Seven baseline patterns were identified during 2011 named as: mental health, respiratory, allergic, mechanical pain, cardiometabolic, osteometabolic, and allergic/derma. Of the epidemiological patterns identified in 2015, six were already present in 2011 but a new allergic/derma one appeared. Patterns identified in 2011 were more complex in terms of both disease and drugs. Results confirmed the existing association between age and clinical complexity. The systematic associations between diseases and drugs remain similar regarding their clinical nature over time, helping in early identification of potential interactions in multimorbid patients with a high risk of negative health outcomes due to polypharmacy
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