Eventos mutuamente excluyentes y eventos independientes: concepciones y dificultades

El presente trabajo tiene como objetivo profundizar en el estudio y caracterización de los errores en estudiantes de nivel superior acerca de los conceptos de eventos mutuamente excluyentes e independientes. Ciertamente observaciones previas de actitudes y respuestas a exámenes en los alumnos de nivel universitario que aprueban un primer curso de Estadística, han detectado confusiones entre eventos mutuamente excluyentes e independientes, e indicado algunas de las ideas espontáneas que tienden a elaborar acerca de ambos conceptos en las diferentes situaciones en las que esta noción entra en juego .En primer lugar es usual que asocien eventos ajenos a eventos independientes. En segundo lugar la independencia se confunde con experiencias independientes, sin que se explicite la diferencia entre ambas nociones. En tercer lugar la confusión se debe a la causalidad. Si bien el concepto de eventos independientes y mutuamente excluyentes es aparentemente sencillo, las ideas espontáneas de las personas dan lugar a respuestas equivocadas. Aquí entra en juego la relación entre la realidad y el objeto matemático puesto en juego. En este trabajo se analizan las concepciones erróneas del sujeto frente a determinadas situaciones, cuando se ha tenido acercamiento a discusiones de la definición del concepto de eventos independientes y mutuamente excluyentes en un curso de probabilidad, qué tan persistentes son esas ideas, qué ocurre en el proceso en el que el sujeto confronta sus concepciones erróneas con los resultados de la aplicación de los conceptos teóricos, con el fin de proporcionar elementos para su mejor tratamiento e implementación en la enseñanza

Infectious agents and inflammation. The role of microbiota in autoimmune arthritis

In higher vertebrates, mucosal sites at the border between the internal and external environments, directly interact with bacteria, viruses, and fungi. Through co-evolution, hosts developed mechanisms of tolerance or ignorance toward some infectious agents, because hosts established "gain of function" interactions with symbiotic bacteria. Indeed, some bacteria assist hosts in different functions, among which are digestion of complex carbohydrates, and absorption and supply of vitamins. There is no doubt that microbiota modulate innate and acquired immune responses starting at birth. However, variations in quality and quantity of bacterial species interfere with the equilibrium between inflammation and tolerance. In fact, correlations between gut bacteria composition and the severity of inflammation were first described for inflammatory bowel diseases and later extended to other pathologies. The genetic background, environmental factors (e.g., stress or smoking), and diet can induce strong changes in the resident bacteria which can expose the intestinal epithelium to a variety of different metabolites, many of which have unknown functions and consequences. In addition, alterations in gut permeability may allow pathogens entry, thereby triggering infection and/or chronic inflammation. In this context, a local event occurring at a mucosal site may be the triggering cause of an autoimmune reaction that eventually involves distant sites or organs. Recently, several studies attributed a pathogenic role to altered oral microbiota in rheumatoid arthritis (RA) and to gut dysbiosis in spondyloarthritis (SpA). There is also growing evidence that different drugs, such as antibiotics and immunosuppressants, can influence and be influenced by the diversity and composition of microbiota in RA and SpA patients. Hence, in complex disorders such RA and SpA, not only the genetic background, gender, and immunologic context of the individual are relevant, but also the history of infections and the structure of the microbial community at mucosal sites should be considered. Here the role of the microbiota and infections in the initiation and progression of chronic arthritis is discussed, as well as how these factors can influence a patient's response to synthetic and biologic immunosuppressive therapy

Introduction

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Current status of prescribed burning laws in Italy, Spain, and Portugal: A comparative study

Mestrado em Gestão da Floresta e dos Recursos Naturais no Mediterrâneo. Universidade de Lisboa, Instituto Superior de AgronomiaPrescribed burning (PB) is a practice that reduces wildfire hazard by burning excessive vegetation under specific topographical and environmental conditions, and with the supervision of qualified personnel. Fire-adapted ecosystems benefit most from PB. Additionally, PB aids with some land management objectives. In the Mediterranean European region, this practice could represent a great opportunity to lessen the negative impacts caused every year by large wildfires. However, PB is not homogenously applied across Southern Europe. PB is mainly limited by policies that restrict its use. While there is some general information about the current state of laws governing PB in Southern Europe, there is no study that goes into detail about the policies. This study reviews and compares the PB policies of Portugal, Spain, and Italy, three nations where PB is used, by emphasizing key elements. Only Portugal has a national legislative framework for PB; in Spain and Italy, it is primarily governed on a regional scale. Catalonia, with a comprehensive decree-law, has provided the most stringent rules for PB in Spain. Recent laws in Italy's Campania and Apulia have been approved solely for the use of PB. The remaining Spanish and Italian Regions regulate PB either via legislations or plans for wildfire management, with varying degrees of restriction. The technical directives and objectives for PB operations vary regionally depending on local geographical conditions. Currently, only the Catalan and Portuguese laws outline the necessary training course for PB-qualified staff, whilst in the other regions the identification of the authorized personnel is not clear. The study also discusses the implementation of PB in the agro-pastoral context. The study identifies which regulatory models aid the implementation of PB the most while addressing the gaps in the legal frameworks for PB in Southern Europe.O fogo controlado (FC) é uma prática que reduz o risco de incêndios florestais reduzindo a quantidade de vegetação (biomassa) sob condições topográficas e ambientais específicas e com a supervisão de pessoal qualificado. Os ecossistemas adaptados ao fogo beneficiam desta utilização do fogo controlado. Além disso, o fogo controlado permite gerir a vegetação ao nível da paisagem. Na Europa mediterrânica, esta prática pode representar uma oportunidade para diminuir os danos anualmente causados por grandes incêndios florestais. Porém, o uso do fogo controlado não é aplicado de forma homogénea em todo o Mediterrâneo. A sua utilização é limitada principalmente por políticas que restringem o seu uso. Embora existam algumas informações gerais sobre o estado das leis que regem o FC na Europa mediterrânica, não há nenhum estudo que entre em detalhes sobre as Políticas. Este estudo analisa e compara as Políticas de Fogo Controlado em Portugal, Espanha e Itália, enfatizando os seus elementos-chave. Apenas Portugal tem um quadro legislativo nacional para o FC; em Espanha e em Itália, o FC é regido principalmente a nível regional. A Catalunha-Espanha, tem um decreto-lei de 2005 bastante abrangente sendo a região autónoma espanhola com as regras mais rigorosas. Em Itália, leis recentes nas regiões italianas da Campânia e Apúlia foram aprovadas exclusivamente para o controle do FC. As restantes regiões espanholas e italianas regulam o FC por leis ou planos de gestão de incêndios florestais, com diferentes graus de restrição. As diretivas técnicas para as operações de FC variam regionalmente em função das condições geográficas locais. Apenas as leis Catalã e Portuguesa definem a formação necessária para o pessoal qualificado para o FC, enquanto nas outras regiões a identificação do pessoal autorizado não é clara. O estudo também discute a implementação do FC no contexto Agro-pastoril. O estudo identifica quais os modelos regulamentares que mais contribuem para a implementação do FC, enquanto aponta as lacunas nos quadros jurídicos do FC na Europa Mediterrânica.N/

Microbiota and chronic inflammatory arthritis. an interwoven link

Background: Only recently, the scientific community gained insights on the importance of the intestinal resident flora for the host's health and disease. Gut microbiota in fact plays a crucial role in modulating innate and acquired immune responses and thus interferes with the fragile balance inflammation versus tolerance. Main body: Correlations between gut bacteria composition and the severity of inflammation have been studied in inflammatory bowel diseases. More recently similar alterations in the gut microbiota have been reported in patients with spondyloarthritis, whereas in rheumatoid arthritis an accumulating body of evidence evokes a pathogenic role for the altered oral microbiota in disease development and course. In the context of dysbiosis it is also important to remember that different environmental factors like stress, smoke and dietary components can induce strong bacterial changes and consequent exposure of the intestinal epithelium to a variety of different metabolites, many of which have an unknown function. In this perspective, and in complex disorders like autoimmune diseases, not only the genetic makeup, sex and immunologic context of the individual but also the structure of his microbial community should be taken into account. Conclusions: Here we provide a review of the role of the microbiota in the onset, severity and progression of chronic inflammatory arthritis as well as its impact on the therapeutic management of these patients. Furthermore we point-out the complex interwoven link between gut-joint-brain and immune system by reviewing the most recent data on the literature on the importance of environmental factors such as diet, smoke and stress

Vitamin D Deficiency and Risk of Metabolic Syndrome in Aging Men.

The elderly population is rapidly increasing; hence, the disability due to age-related diseases has become an important socioeconomic burden. Amongst age-related diseases cardiovascular ones (CVD) have a huge impact on morbidity and mortality and are associated with metabolic syndrome (MetS). Several studies investigated the role of hypovitaminosis D in the pathogenesis of MetS and of CVD, this review unravels the relationship between aging/senescence, vitamin D, gender, and pathogenesis of MetS

Measuring the complex orbital angular momentum spectrum and spatial mode decomposition of structured light beams

Light beams carrying orbital angular momentum are key resources in modern photonics. In many applications, the ability of measuring the complex spectrum of structured light beams in terms of these fundamental modes is crucial. Here we propose and experimentally validate a simple method that achieves this goal by digital analysis of the interference pattern formed by the light beam and a reference field. Our approach allows one to characterize the beam radial distribution also, hence retrieving the entire information contained in the optical field. Setup simplicity and reduced number of measurements could make this approach practical and convenient for the characterization of structured light fields.Comment: 8 pages (including Methods and References), 6 figure

La TURbomacchina solare nelle applicazioni spaziali

Fra i vari sistemi (li conversione di energia per applicazionispaziali la turbomacchina solare a vapore presenta uno dei campidi applicazione più vasto nei riguardi della potenza.Nel presente lavoro vengono esaminati taluni fra i principali problemiinerenti a tale tipo di macchina, con particolare riguardo alla scelta del ciclotermico e del fluido operante. Per quest'ultimo vengono indicate quelle chesono le caratteristiche ideali

Immagini letterarie di Parigi fine secolo

L'articolo si propone di descrivere l'impatto della metropoli haussmaniana sulla sensibilità di alcuni scrittori della fine secol

Hypovitaminosis D and Aging: Is There a Role in Muscle and Brain Health?

The older-adult population is constantly increasing, hence aging and mechanisms leading to aging are a topic raising increasing interest. Hypovitaminosis D is common amongst old patients and has been proposed as causative of several chronic diseases. Here we review the role of hypovitaminosis D and vitamin D supplementation in sarcopenia and dementia, from bench to bedside