2,028 research outputs found

    Mixed bag “polypharmacy”: methodological pitfalls and challenges of this exposure definition

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    Purpose of Review The use of multiple medications is common in older adults but is associated with negative health outcomes. However, polypharmacy is not uniformly defined, and there is scant data on how the variety of definitions and their limitations hinder the development of sound scientific knowledge. The article intends to illustrate the challenges of this exposure definition. Recent Findings The array of thresholds for defining polypharmacy renders comparisons between results difficult. Few studies take into account the fact that polypharmacy is a changing exposure over time. In addition, although studies tend to recognize the confounding effect of multimorbidity, residual bias remains a concern. Summary Current studies in polypharmacy often ignore basic epidemiological principles for defining exposure. Future research should integrate time-varying exposure and methods to better control confounding bias. This will help determine the positive/negative impacts of polypharmacy and help establish if polypharmacy conveys information beyond being a marker of health status

    Desarrollo de la inhibición: comparación de medidas neuropsicológicas y de seguimiento de ojos

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    Inhibition is the ability to stop an automatic response when a stimulus is presented. It is one main component of executive function models. Few studies have evaluated the development of this ability’s in children between five and eight years of age using eye tracking measures. The first objective of this exploratory study is to evaluate the performance difference of younger compared to older children. The second objective is to evaluate if inhibition assessed via three different neuropsychological tests develops at a similar rate as inhibition assessed via two eye tracking tasks. Forty-six children aged 5.7 to 8.4 years completed both types of tests. Results show that one neuropsychological test was sensitive to the children’ increasing inhibition ability, while both eye tracking tests were. Additionally, scores from one eye tracking task correlated with scores from one neuropsychological test. Possible explanations of moderate relations between tasks are discussed.La inhibición es la capacidad de detener una respuesta automática. Es una de las funciones ejecutivas principales. Pocos estudios han evaluado su desarrollo en niños de cinco a ocho años utilizando pruebas de seguimiento de ojos. Este estudio exploratorio tiene, como primer objetivo, evaluar la diferencia de rendimiento entre los más jóvenes y los mayores. El segundo objetivo es evaluar si la inhibición se desarrolla a un ritmo similar en tres pruebas neuropsicológicas y dos pruebas de seguimiento de ojos. Cuarenta y seis niños, de 5 años y 8 meses a 8 años y 5 meses, realizaron ambos tipos de pruebas. Los resultados muestran que una de las pruebas neuropsicológicas y ambas pruebas de seguimiento de ojos fueron sensibles a la mejora de la inhibición. Además, resultados de una prueba de seguimiento de ojos y de una prueba neuropsicológica estaban correlacionados. Se discuten las explicaciones posibles de las relaciones entre las tareas

    Does socio-economic status influence the effect of multimorbidity on the frequent use of ambulatory care services in a universal healthcare system? A population-based cohort study

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    Background: Frequent healthcare users place a significant burden on health systems. Factors such as multimorbidity and low socioeconomic status have been associated with high use of ambulatory care services (emergency rooms, general practitioners and specialist physicians). However, the combined effect of these two factors remains poorly understood. Our goal was to determine whether the risk of being a frequent user of ambulatory care is influenced by an interaction between multimorbidity and socioeconomic status, in an entire population covered by a universal health system. Methods: Using a linkage of administrative databases, we conducted a population-based cohort study of all adults in Quebec, Canada. Multimorbidity (defined as the number of different diseases) was assessed over a two-year period from April 1st 2012 to March 31st 2014 and socioeconomic status was estimated using a validated material deprivation index. Frequents users for a particular category of ambulatory services had a number of visits among the highest 5% in the total population during the 2014–15 fiscal year. We used ajusted logistic regressions to model the association between frequent use of health services and multimorbidity, depending on socioeconomic status. Results: Frequent users (5.1% of the population) were responsible for 25.2% of all ambulatory care visits. The lower the socioeconomic status, the higher the burden of chronic diseases, and the more frequent the visits to emergency departments and general practitioners. Socioeconomic status modified the association between multimorbidity and frequent visits to specialist physicians: those with low socioeconomic status visited specialist physicians less often. The difference in adjusted proportions of frequent use between the most deprived and the least deprived individuals varied from 0.1% for those without any chronic disease to 5.1% for those with four or more chronic diseases. No such differences in proportions were observed for frequent visits to an emergency room or frequent visits to a general practitioner

    Antimicrobial susceptibility patterns of eampylobacter coli isolates from swine and humans

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    An increase in resistance to various antimicrobial agents has been reported in many countries for Campylobacter species. In order to study their resistance profiles to various antimicrobial agents, strains ofC. coli isolated from slaughtered pigs and from human patients were examined for resistance to quinolones and other antimicrobial agents by agar dilution technique. Resistance to tetracycline was common for human (53 %) and swine (68 %) isolates. Higher level of resistance to streptomycine was found in swine isolates (67 %) than in human (24 %) isolates. Human isolates were more frequently found to be resistant to enrofloxacin and ciprofloxacin (18 and 24 %) than swine isolates (7 and II %). Sixty one percent C. coli from swine were resistant to erythromycine while only 12 %of C. coli of human origin were resistant. Emergence of resistance to macrolides, tetracyclines and quinolones is of interest in regard with possible dissemination of genetic resistance determinants to humans

    L’histoire de l’art au Canada : pratiques actuelles d’une discipline universitaire

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    Pour répondre à l’étonnement admiratif de nos collègues français devant la popularité croissante de notre discipline au Canada auprès des étudiants, des chercheurs et du grand public dans un pays où l’histoire de l’art s’est développée depuis seulement une ou deux générations, j’ai proposé à trois enseignants universitaires – dont une muséologue directrice d’une galerie d’université – des thèmes de réflexion pour éclairer le phénomène et décrire la diversité des approches et des méthodes selo..

    Energy Resolution Performance of the CMS Electromagnetic Calorimeter

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    The energy resolution performance of the CMS lead tungstate crystal electromagnetic calorimeter is presented. Measurements were made with an electron beam using a fully equipped supermodule of the calorimeter barrel. Results are given both for electrons incident on the centre of crystals and for electrons distributed uniformly over the calorimeter surface. The electron energy is reconstructed in matrices of 3 times 3 or 5 times 5 crystals centred on the crystal containing the maximum energy. Corrections for variations in the shower containment are applied in the case of uniform incidence. The resolution measured is consistent with the design goals

    Life in the fast lane: Revisiting the fast growth—High survival paradigm during the early life stages of fishes

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    Early life survival is critical to successful replenishment of fish populations, and hypotheses developed under the Growth-Survival Paradigm (GSP) have guided investigations of controlling processes. The GSP postulates that recruitment depends on growth and mortality rates during early life stages, as well as their duration, after which the mortality declines substantially. The GSP predicts a shift in the frequency distribution of growth histories with age towards faster growth rates relative to the initial population because slow-growing individuals are subject to high mortality (via starvation and predation). However, mortality data compiled from 387 cases published in 153 studies (1971–2022) showed that the GSP was only supported in 56% of cases. Selection against slow growth occurred in two-thirds of field studies, leaving a non-negligible fraction of cases showing either an absence of or inverse growth-selective survival, suggesting the growth-survival relationship is more complex than currently considered within the GSP framework. Stochastic simulations allowed us to assess the influence of key intrinsic and extrinsic factors on the characteristics of surviving larvae and identify knowledge gaps on the drivers of variability in growth-selective survival. We suggest caution when interpreting patterns of growth selection because changes in variance and autocorrelation of individual growth rates among cohorts can invalidate fundamental GSP assumptions. We argue that breakthroughs in recruitment research require a comprehensive, population-specific characterization of the role of predation and intrinsic factors in driving variability in the distribution and autocorrelation of larval growth rates, and of the life stage corresponding to the endpoint of pre-recruited life. -- Keywords : critical period ; growth-mortality ; individual characteristics ; larval physiology ; predation ; recruitment endpoint

    Increasing fire and the decline of fire adapted black spruce in the boreal forest

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    Intensifying wildfire activity and climate change can drive rapid forest compositional shifts. In boreal North America, black spruce shapes forest flammability and depends on fire for regeneration. This relationship has helped black spruce maintain its dominance through much of the Holocene. However, with climate change and more frequent and severe fires, shifts away from black spruce dominance to broadleaf or pine species are emerging, with implications for ecosystem functions including carbon sequestration, water and energy fluxes, and wildlife habitat. Here, we predict that such reductions in black spruce after fire may already be widespread given current trends in climate and fire. To test this, we synthesize data from 1,538 field sites across boreal North America to evaluate compositional changes in tree species following 58 recent fires (1989 to 2014). While black spruce was resilient following most fires (62%), loss of resilience was common, and spruce regeneration failed completely in 18% of 1,140 black spruce sites. In contrast, postfire regeneration never failed in forests dominated by jack pine, which also possesses an aerial seed bank, or broad-leaved trees. More complete combustion of the soil organic layer, which often occurs in better-drained landscape positions and in dryer duff, promoted compositional changes throughout boreal North America. Forests in western North America, however, were more vulnerable to change due to greater long-term climate moisture deficits. While we find considerable remaining resilience in black spruce forests, predicted increases in climate moisture deficits and fire activity will erode this resilience, pushing the system toward a tipping point that has not been crossed in several thousand years

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis
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