998 resultados para Su-Schrieffer-Heeger models


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Prevention of Trypanosoma cruzi infection in mammals likely depends on either prevention of the invading trypomastigotes from infecting host cells or the rapid recognition and killing of the newly infected cells byT. cruzi-specific T cells. We show here that multiple rounds of infection and cure (by drug therapy) fails to protect mice from reinfection, despite the generation of potent T cell responses. This disappointing result is similar to that obtained with many other vaccine protocols used in attempts to protect animals from T. cruziinfection. We have previously shown that immune recognition ofT. cruziinfection is significantly delayed both at the systemic level and at the level of the infected host cell. The systemic delay appears to be the result of a stealth infection process that fails to trigger substantial innate recognition mechanisms while the delay at the cellular level is related to the immunodominance of highly variable gene family proteins, in particular those of the trans-sialidase family. Here we discuss how these previous studies and the new findings herein impact our thoughts on the potential of prophylactic vaccination to serve a productive role in the prevention of T. cruziinfection and Chagas disease.

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Los ciclones tropicales son los fenómenos climatológicos más destructivos. El PDI y otros índices que se definen aquí permiten estimar la energía que éstos poseen. Tales índices ajustan una ley de potencias en una parte de su recorrido. En el presente trabajo se procede al ajuste de las respectivas leyes de potencias de los índices para los ciclones tropicales en el norte del Océano Atlántico y noreste del Pacífico en los periodos de 1988 a 2010 y de 2001 a 2010 respectivamente, a partir de los datos registrados por el NOAA.

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BACKGROUND: There is a prevalence of diabetes mellitus (DM), unknown DM and stress hyperglycemia among hospital patients, and the nutritional treatment is a key part of care, where carbohydrates (CH) intake is a controversial issue. There is also a discussion on the increase of prevalence for DM, obesity and metabolic disease with refined CH or sugar. OBJECTIVES: This review examines the recommendations from different scientific societies about the percentage of CH in the total calorie intake of the diabetic patient, the CH value in the glycemic index and glycemic load, the new CH included in enteral formulae and the association of refined CH with the high prevalence of DM and metabolic disease. METHODS: Systematic review of literature using the electronic scientific databases Pubmed, Science Direct, Scielo, Scopus and Medline. CONCLUSIONS: Scientific societies are flexible about the CH intake in the diet of diabetic patients, suggesting to customize it according to each metabolic profile. Using the glycemic index and glycemic load can provide an extra benefit in the postprandial glycemic control. The new diabetes-specific enteral formulae, with fructooligosaccharides, resistant maltodextrins and fructose-free show efficacy in improving the glycemic control, although more controlled and long-term studies are needed. There is still some controversy about the links between sugar intake and DM, obesity and metabolic disease, although this relationship would be more linked to an increase of the total calorie intake than to a specific nutrient. .

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En aquest treball, prenent com a marc teòric de referència la deconstrucció de la dicotomia públic/privat realitzada per la teoría feminista en aquestes últimes dècades, i les anàlisis jurídicfeministes del dret, posem de manifest com el Dret de la Unió Europea sobre la conciliació de la vida familiar i laboral està articulat acord amb aquesta dicotomia, i en conseqüència, no té en compte els interessos de les dones en tot el seu abast, ja que potencia la seva participació en el treball remunerat però sense resoldre el problema de les desigualtats entre homes i dones en relació amb les càrregues familiars i domèstiques.

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The objective of the EU funded integrated project "ACuteTox" is to develop a strategy in which general cytotoxicity, together with organ-specific endpoints and biokinetic features, are taken into consideration in the in vitro prediction of oral acute systemic toxicity. With regard to the nervous system, the effects of 23 reference chemicals were tested with approximately 50 endpoints, using a neuronal cell line, primary neuronal cell cultures, brain slices and aggregated brain cell cultures. Comparison of the in vitro neurotoxicity data with general cytotoxicity data generated in a non-neuronal cell line and with in vivo data such as acute human lethal blood concentration, revealed that GABA(A) receptor function, acetylcholine esterase activity, cell membrane potential, glucose uptake, total RNA expression and altered gene expression of NF-H, GFAP, MBP, HSP32 and caspase-3 were the best endpoints to use for further testing with 36 additional chemicals. The results of the second analysis showed that no single neuronal endpoint could give a perfect improvement in the in vitro-in vivo correlation, indicating that several specific endpoints need to be analysed and combined with biokinetic data to obtain the best correlation with in vivo acute toxicity.

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Benzodiazepines and hypnotic Z-drugs are indicated for the short-term treatment of insomnia and anxiety (4 weeks maximum) at the lowest dose possible. Despite the recommendations for short-term use and its unfavourable effects, the level of consumption of benzodiazepines in our context is high and it is continually rising. Prolonged medication usage is associated with adverse effects and significant risks, particularly in the elderly, and should, therefore, be avoided when approaching new treatment. If a previous treatment assessed is found to be inappropriate, its possible withdrawal must be considered. Benzodiazepines withdrawal is based on a gradual dose reduction and should be managed by establishing a doctor-patient relationship of trust to encourage and accomplish discontinuation.

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Aquest estudi posa a debat tant els nivells com les formes de participació dels estudiants en el funcionament de la universitat amb la finalitat d’aprofundir en els models i les dinàmiques que afavoreixen la participació dels estudiants. Parteix de l’estudi del cas de la Universitat de Girona i recull, des de diferents punts de vista, quina és la situació actual pel que fa a la participació dels estudiants en aquesta universitat, i es proposen algunes línies d’actuació per promoure-la. A la base d’aquest estudi se situa el convenciment que la participació dels estudiants en el funcionament de la universitat és un objectiu desitjable per part de la comunitat universitària, i que, com a centre de formació que és la universitat, cal que es plantegi la participació com un objectiu d’aprenentatge propi ja que, a més de formar científi cs i professionals en diferents àmbits, la universitat també contribueix (o hauria de contribuir) a la formació de ciutadans. Es tracta d’un treball fi nançat per la convocatòria 20 de la UdG d’ajuts a projectes cooperatius d’R+D en els àmbits humanístic i de les ciències socials i que s’ha desenvolupat en la seva major part durant l’any 2008 i inicis del 2009. Les dades de participació que es presenten sobre la UdG són de l’any 2008

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This paper investigates the role of learning by private agents and the central bank (two-sided learning) in a New Keynesian framework in which both sides of the economy have asymmetric and imperfect knowledge about the true data generating process. We assume that all agents employ the data that they observe (which may be distinct for different sets of agents) to form beliefs about unknown aspects of the true model of the economy, use their beliefs to decide on actions, and revise these beliefs through a statistical learning algorithm as new information becomes available. We study the short-run dynamics of our model and derive its policy recommendations, particularly with respect to central bank communications. We demonstrate that two-sided learning can generate substantial increases in volatility and persistence, and alter the behavior of the variables in the model in a signifficant way. Our simulations do not converge to a symmetric rational expectations equilibrium and we highlight one source that invalidates the convergence results of Marcet and Sargent (1989). Finally, we identify a novel aspect of central bank communication in models of learning: communication can be harmful if the central bank's model is substantially mis-specified

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INTRODUCTION: Morbid obesity has grown enormously in recent decades, representing a serious public health problem. It is characterized by the accumulation of body fat and the presence of diseases associated with it, which affects the physical, psychological and social level. It has been considered bariatric ciguría as the most effective treatment for weight loss, getting the welfare of the obese person in the above-described drawings. OBJECTIVE: To evaluate the impact on the quality of life of obese people before and after bariatric surgery be tapped using the technique of laparoscopic gastrectomy (GVL) in a follow short, medium and long term. METHOD: The study population are all people with morbid obesity and are candidates for surgery, presenting at Torrecárdenas Bariatric Surgery Hospital (Almería). The design is a descriptive, longitudinal study, prospective. RESULTS: After evaluation of the obese patients a year, two years and five years after surgery, there has been decrease in weight, therefore decrease in BMI and the degree of obesity, improvement or disappearance of comorbidities and increased CV variables. DISCUSSION: The GVL gets reduce excess weight and therefore BMI and the degree of obesity, as well as the number of obesity-associated diseases, thus increasing the CV.

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Uno de los puntos que se destacará en este trabajo es la reorientación de las relaciones políticas y económicas de los diferentes actores implicados en Oriente Medio para darles unas connotaciones más regionales. Esta tendencia también es perceptible en otras regiones del mundo en las que se combinan globalización con regionalismo de tal modo que un proceso fortalece al otro y originan una mayor cooperación.

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The paper discusses maintenance challenges of organisations with a huge number of devices and proposes the use of probabilistic models to assist monitoring and maintenance planning. The proposal assumes connectivity of instruments to report relevant features for monitoring. Also, the existence of enough historical registers with diagnosed breakdowns is required to make probabilistic models reliable and useful for predictive maintenance strategies based on them. Regular Markov models based on estimated failure and repair rates are proposed to calculate the availability of the instruments and Dynamic Bayesian Networks are proposed to model cause-effect relationships to trigger predictive maintenance services based on the influence between observed features and previously documented diagnostics

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Enfrentar la muerte como final inevitable de todo ser humano es una cuestión que ha preocupado a la humanidad desde sus orígenes y ha motivado innumerable literatura en todos los tiempos. Quizás por esta razón, la actuación del profesional sanitario en el tramo final de la vida de sus pacientes se ha enmarcado tradicionalmente en la toma de decisiones individuales o bien de forma conjunta con la familia del enfermo, debatiéndose entre su máxima aspiración de salvar esa vida y la aceptación del desenlace inevitable como consecuencia de la enfermedad. Poco a poco se va interiorizando la obligación ética y deontológica de saber ver el momento en el que hay que decir basta y limitarse a acompañar al paciente en su proceso de muerte, haciéndolo lo más indoloro y apacible que se pueda.

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Our work is concerned with user modelling in open environments. Our proposal then is the line of contributions to the advances on user modelling in open environments thanks so the Agent Technology, in what has been called Smart User Model. Our research contains a holistic study of User Modelling in several research areas related to users. We have developed a conceptualization of User Modelling by means of examples from a broad range of research areas with the aim of improving our understanding of user modelling and its role in the next generation of open and distributed service environments. This report is organized as follow: In chapter 1 we introduce our motivation and objectives. Then in chapters 2, 3, 4 and 5 we provide the state-of-the-art on user modelling. In chapter 2, we give the main definitions of elements described in the report. In chapter 3, we present an historical perspective on user models. In chapter 4 we provide a review of user models from the perspective of different research areas, with special emphasis on the give-and-take relationship between Agent Technology and user modelling. In chapter 5, we describe the main challenges that, from our point of view, need to be tackled by researchers wanting to contribute to advances in user modelling. From the study of the state-of-the-art follows an exploratory work in chapter 6. We define a SUM and a methodology to deal with it. We also present some cases study in order to illustrate the methodology. Finally, we present the thesis proposal to continue the work, together with its corresponding work scheduling and temporalisation

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BACKGROUND: Fractures in men are a major health issue, and data on the antifracture efficacy of therapies for osteoporosis in men are limited. We studied the effect of zoledronic acid on fracture risk among men with osteoporosis. METHODS: In this multicenter, double-blind, placebo-controlled trial, we randomly assigned 1199 men with primary or hypogonadism-associated osteoporosis who were 50 to 85 years of age to receive an intravenous infusion of zoledronic acid (5 mg) or placebo at baseline and at 12 months. Participants received daily calcium and vitamin D supplementation. The primary end point was the proportion of participants with one or more new morphometric vertebral fractures over a period of 24 months. RESULTS: The rate of any new morphometric vertebral fracture was 1.6% in the zoledronic acid group and 4.9% in the placebo group over the 24-month period, representing a 67% risk reduction with zoledronic acid (relative risk, 0.33; 95% confidence interval, 0.16 to 0.70; P=0.002). As compared with men who received placebo, men who received zoledronic acid had fewer moderate-to-severe vertebral fractures (P=0.03) and less height loss (P=0.002). Fewer participants who received zoledronic acid had clinical vertebral or nonvertebral fractures, although this difference did not reach significance because of the small number of fractures. Bone mineral density was higher and bone-turnover markers were lower in the men who received zoledronic acid (P<0.05 for both comparisons). Results were similar in men with low serum levels of total testosterone. The zoledronic acid and placebo groups did not differ significantly with respect to the incidence of death (2.6% and 2.9%, respectively) or serious adverse events (25.3% and 25.2%). CONCLUSIONS: Zoledronic acid treatment was associated with a significantly reduced risk of vertebral fracture among men with osteoporosis. (Funded by Novartis Pharma; ClinicalTrials.gov number, NCT00439647.).