168 research outputs found

    Influencia del enfriamiento en las propiedades de titanatos de lantano y litio

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    Se ha estudiado el efecto de los tratamientos a alta temperatura sobre la estructura y la movilidad del litio para la solución sÛlida Li3xLa2/3-xTiO3 (0.03<x<0.167) con difracciÛn de rayos X a alta temperatura (DRXAT), espectroscopia Raman, RMN y de impedancias. Los patrones de difracción de rayos X (DRX) a temperatura ambiente de muestras enfriadas lentamente muestran una estructura tipo perovskita doblada en el eje c con simetrÌas tetragonales u ortorrómbicas, mientras que las muestras con un enfriamiento r·pido muestran una estructura tipo perovskita c ̇bica simple. Sin embargo, el espectro Raman de las muestras analizadas se interpreta, en todos los casos, con una simetrÌa tetragonal en la que el desorden catiónico se incrementa con el contenido de litio y el tratamiento de enfriamiento. La existencia de microdominios de maclado, orientados a lo largo de las tres direcciones de la perovski- ta, favorece la detecciÛn de la fase c ̇bica en los patrones de DRX. A partir de la espectroscopia de RMN del 7Li, se ha detectado un movimiento bidi- mensional del litio en las muestras ordenadas, el cual se convierte progresivamente en un movimiento tridimensional conforme se incrementa el desorden catiÛnico. Asimismo, la presencia de microdominios hace disminuir la conductividad dc de muestras con contenidos bajos de litio

    Spatial and Temporal Characteristics of the 2009 A/H1N1 Influenza Pandemic in Peru

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    Background: Highly refined surveillance data on the 2009 A/H1N1 influenza pandemic are crucial to quantify the spatial and temporal characteristics of the pandemic. There is little information about the spatial-temporal dynamics of pandemic influenza in South America. Here we provide a quantitative description of the age-specific morbidity pandemic patterns across administrative areas of Peru. Methods: We used daily cases of influenza-like-illness, tests for A/H1N1 influenza virus infections, and laboratory-confirmed A/H1N1 influenza cases reported to the epidemiological surveillance system of Peru’s Ministry of Health from May 1 to December 31, 2009. We analyzed the geographic spread of the pandemic waves and their association with the winter school vacation period, demographic factors, and absolute humidity. We also estimated the reproduction number and quantified the association between the winter school vacation period and the age distribution of cases. Results: The national pandemic curve revealed a bimodal winter pandemic wave, with the first peak limited to school age children in the Lima metropolitan area, and the second peak more geographically widespread. The reproduction number was estimated at 1.6–2.2 for the Lima metropolitan area and 1.3–1.5 in the rest of Peru. We found a significant association between the timing of the school vacation period and changes in the age distribution of cases, while earlier pandemic onset was correlated with large population size. By contrast there was no association between pandemic dynamics and absolute humidity. Conclusions: Our results indicate substantial spatial variation in pandemic patterns across Peru, with two pandemic waves of varying timing and impact by age and region. Moreover, the Peru data suggest a hierarchical transmission pattern of pandemic influenza A/H1N1 driven by large population centers. The higher reproduction number of the first pandemic wave could be explained by high contact rates among school-age children, the age group most affected during this early wave

    Multimorbidity clusters in patients with chronic obstructive airway diseases in the EpiChron Cohort

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    Chronic obstructive airway diseases such as chronic obstructive pulmonary disease (COPD), asthma, rhinitis, and obstructive sleep apnea (OSA) are amongst the most common treatable and preventable chronic conditions with high morbidity burden and mortality risk. We aimed to explore the existence of multimorbidity clusters in patients with such diseases and to estimate their prevalence and impact on mortality. We conducted an observational retrospective study in the EpiChron Cohort (Aragon, Spain), selecting all patients with a diagnosis of allergic rhinitis, asthma, COPD, and/or OSA. The study population was stratified by age (i.e., 15–44, 45–64, and = 65 years) and gender. We performed cluster analysis, including all chronic conditions recorded in primary care electronic health records and hospital discharge reports. More than 75% of the patients had multimorbidity (co-existence of two or more chronic conditions). We identified associations of dermatologic diseases with musculoskeletal disorders and anxiety, cardiometabolic diseases with mental health problems, and substance use disorders with neurologic diseases and neoplasms, amongst others. The number and complexity of the multimorbidity clusters increased with age in both genders. The cluster with the highest likelihood of mortality was identified in men aged 45 to 64 years and included associations between substance use disorder, neurologic conditions, and cancer. Large-scale epidemiological studies like ours could be useful when planning healthcare interventions targeting patients with chronic obstructive airway diseases and multimorbidity

    Practical Guidelines for Perioperative Hypersensitivity Reactions

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    Perioperative hypersensitivity reactions constitute a first-line problem for anesthesiologists and allergists. Therefore, hospitals should have a consensus protocol for the diagnosis and management of these reactions. However, this kind of protocol is not present in many hospitals, leading to problems with treatment, reporting of incidents, and subsequent etiological diagnosis. In this document, we present a systematic review of the available scientific evidence and provide general guidelines for the management of acute episodes and for referral of patients with perioperative hypersensitivity reactions to allergy units. Members of the Drug Allergy Committee of the Spanish Society of Allergy and Clinical Immunology (SEAIC) have created this document in collaboration with members of the Spanish Anesthesia Society (SEDAR). A practical algorithm is proposed for the etiologic diagnosis, and recommendations are provided for the management of hypersensitive patients

    Desarrollo de una presentación interactiva y multimedia orientada a la docencia del análisis cinemático del Movimiento Armónico Simple

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    Nowadays, computers suppose a great potential as complementary didactic tool to traditional means of education. For that reason, the advantage of this potential is considered by the work group, creating interactive and multimedia presentations oriented to facilitate teaching of different physics fields. In particular, the objective of this work is the design of a presentation oriented to teaching kinematical aspects of the simple harmonic movement. Given the dynamic nature of the subject, it is evident the adventages that suppose an animated presentation which it helps the student to understand the kinematical magnitudes. This tool will be very useful to the professor as complement of theoretical classes, and available to the students in the reinforcement of the knowledge.Es evidente el gran potencial que el ordenador supone como herramienta didáctica complementaria a los medios de enseñanza tradicionales. Es por ello que el grupo de trabajo se plantea el aprovechamiento de este potencial, creando presentaciones interactivas y multimedia orientadas a la docencia en los distintos campos de la física.En concreto, en este trabajo se plantea el diseño de una presentación orientada a la docencia de los aspectos cinemáticas del movimiento armónico simple. Dada la naturaleza dinámica del tema en cuestión, es evidente las ventajas que supone disponer de una presentación animada del mismo que ayude al alumno a entender la magnitudes cinemáticas implicadas, herramientas de gran utilidad para el profesor como complemento de sus clases teóricas, y disponible para alumnos de ayuda en el afianzamiento de los conocimientos

    Cohort Profile: The epidemiology of chronic diseases and multimorbidity. The EpiChron cohort study

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    Why was the cohort set up? Greater life expectancy in Europe over the past few decades has been translated into an increasing burden of chronic diseases that accumulate as the population ages, whereas acute infectious diseases have been progressively pushed into the background. The incidence of conditions such as hypertension, obesity and asthma has increased dramatically worldwide, and cancer, diabetes and respiratory and cardiovascular diseases are responsible for almost 70% of global deaths. Concurrently, the prevalence of multimorbidity (as of people affected by more than one chronic disorder) is also increasing and appears as the most common chronic condition at present. Multimorbidity affects almost 3 in 4 individuals aged 65 years and older, although it represents a problem not only for the elderly but also for adult and even young populations, at whom prevention strategies should aim. People affected by multimorbidity often experience fragmentation of care, greater and inadequate use of health services and polypharmacy, which in turn may increase the risk of low adherence and adverse drug reactions. All of this leads to individuals’ quality of life deterioration and higher risk of mortality. Besides, handling patients with multimorbidity represents a daily challenge for physicians and health systems..

    Efficacy of mefloquine in the treatment of skin leishmaniasis in an endemic area of Leishmania (Viannia) braziliensis

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    O objetivo deste trabalho foi avaliar a eficácia da mefloquina numa região endêmica de leishmaniose cutânea por Leishmania (Viannia) braziliensis, considerando que esta droga de administração oral, eficaz no tratamento da malária, com meia vida prolongada e efeitos colaterais pouco freqüentes poderia ser menos tóxica e de mais fácil administração, quando comparada com os antimoniais pentavalentes. Em Corte de Pedra, no litoral sul do Estado da Bahia, foram tratados, aleatoriamente, dez pacientes portadores de lesões leishmanióticas, subdivididos em dois grupos. O primeiro grupo recebeu mefloquina pela via oral, dose de 250mg/dia, durante seis dias, repetindo-se o mesmo esquema após intervalo de três semanas. O segundo grupo recebeu antimoniato de meglumina (Glucantime®) diariamente, pela via endovenosa, na dose de 20mg/kg por 20 dias. Do grupo da mefloquina só um paciente apresentou cicatrização depois do segundo ciclo. Um desses, com quatro lesões apresentou nova lesão durante o primeiro ciclo de tratamento. A evolução dos outros três foi lenta sendo que em nove semanas nenhum deles tinha cicatrizado as úlceras que permaneciam com grande infiltração e sinais evidentes de atividade. O grupo tratado com Glucantime® apresentou evidente melhora.The aim of this study was to evaluate the efficacy of mefloquine in the treatment of skin leishmaniasis in patients infected with Leishmania (Viannia) braziliensis at an endemic region. Mefloquine is an oral drug effective against malaria with a prolonged half-life, less toxicity and easier administration than pentavalent antimonials. At Corte de Pedra in the Southern litoral of Bahia State, two randomized groups of ten patients with leishmaniasis were treated. The first group was treated with oral mefloquine, 250mg per day in a single dose for six days and repeated three weeks later. The second group received meglumine antimoniate (Glucantime®), 20mg/kg daily administered intravenously for 20 days. Only one patient in the group treated with mefloquine showed evidence of clinical success. During treatment, one patient with four lesions developed a new lesion. The other three patients with clinical leismaniasis did not show evidence of clinical success after nine weeks of treatment. The group treated with Glucantime® showed evident clinical improvement of the skin lesions
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