901 research outputs found
Cumulative dominance and heuristic performance in binary multi-attribute choice
Several studies have reported high performance of simple decision heuristics multi-attribute decision making. In this paper, we focus on situations where attributes are binary and analyze the performance of Deterministic-Elimination-By-Aspects (DEBA) and similar decision heuristics. We consider non-increasing weights and two probabilistic models for the attribute values: one where attribute values are independent Bernoulli randomvariables; the other one where they are binary random variables with inter-attribute positive correlations. Using these models, we show that good performance of DEBA is explained by the presence of cumulative as opposed to simple dominance. We therefore introduce the concepts of cumulative dominance compliance and fully cumulative dominance compliance and show that DEBA satisfies those properties. We derive a lower bound with which cumulative dominance compliant heuristics will choose a best alternative and show that, even with many attributes, this is not small. We also derive an upper bound for the expected loss of fully cumulative compliance heuristics and show that this is moderate even when the number of attributes is large. Both bounds are independent of the values of the weights.Multi-attribute decision making, binary attributes, DEBA, cumulative dominance, performance bounds, Leex
Els misteris del sistema immunitari... o com difondre la immunologia en català de manera senzilla, ...però científicament impecable
Malalties immunomediades (immunopatologia) en el moment actual
Sota el terme de malalties immunomediades (MIM) s'agrupen totes aquelles malalties que tenen la causa de la malaltia en el sistema immunitari més que no pas la solució, com tothom espera del sistema encarregat del manteniment de la integritat de l'individu front a les infeccions. Així, autoimmunitat, immunoquímica, al·lèrgia, immunoteràpia i immunodeficiències serien els cinc grans subgrups d'aquest ampli concepte de MIM. En relació amb el diagnòstic i tractament de les MIM s'encunya el terme immunopatologia per referir-se a l'àrea de suport al diagnòstic per a aquestes malalties. Els avenços en el coneixement, diagnòstic i fins i tot tractament de les MIM són (després dels relacionats amb el coneixement de la genètica i el càncer) l'àrea biomèdica en què més aportacions s'estan fent en les darreres dècades.The term immune-mediated diseases (IMDs) groups together all the illnesses for which the cause is in the immune system rather than the solution as one would expect from the system in charge of upholding the integrity of individuals in the face of infections. Autoimmunity, immunochemistry, allergy, immunotherapy and immunodeficiencies are the 5 major subgroups of this broad concept of IMDs. When it comes to the diagnosis and treatment of IMDs, the term immunopathology has been coined to refer to the area for support in the diagnosis of such pathologies. Progress in the understanding, diagnosis and even treatment of IMDs (after knowledge of genetics and cancer) is the area in which most biomedical contributions have been made in recent decades
El consumo de cocaína: Algunas lecciones de España
In this paper, we examine the socioeconomic factors that determine cocaine consumption in adults aged over 18 years in Spain. For data from household alcohol and drug surveys for the period 2007-2012 (EDADES 2007, 2009, 2011), we used, first, a decision tree to identify the main predictors of cocaine use and high-risk profiles of cocaine consumers and, next, a multinomial logistic regression model to explain cocaine consumption in terms of sex, age, marital status, employment status, education level, income, household size and perceived health status. The results indicate that the main predictors of cocaine use are marital status, sex, employment status, age, education level and household size. The main cocaine user propensity profile is a young single man with a low level of education and unemployed, who should, therefore, be the main target of campaigns for preventing illicit drug use.Este trabajo analiza los factores socioeconómicos que determinan el consumo
de cocaína en adultos españoles de más de 18 años. Con los datos de las encuestas domiciliarias
de alcohol y drogas para el período 2007-2012 (EDADES 2007, 2009, 2011), planteamos
un modelo de árboles de decisión para identificar los principales predictores del consumo de
cocaína, así como los grupos de perfiles con mayor riesgo de consumo. Al mismo tiempo, construimos
un modelo de regresión logística multinomial para explicar el consumo de cocaína y sus
diferentes grados de una persona adulta en función del sexo, la edad, el estado civil, la situación
laboral, el nivel educativo, los ingresos, el tamaño del hogar en el que vive y la percepción
que tiene de su estado de salud. Los resultados muestran que los principales predictores del consumo de cocaína en adultos en España son el estado civil, el sexo, la situación laboral, la edad, el nivel educativo y el tamaño del hogar. El perfil de adultos con mayor propensión al consumo de cocaína es el de varones jóvenes con un bajo nivel de educación, que viven solos y están desempleados. Esta debería ser, pues, la población en la que centrar las campañas de prevención del consumo de drogas ilícita
Postglacial evolution of the Lake of Villaseca (NW Iberian Peninsula) inferred from diatom analysis
[Abstract] The lake of Villaseca is located in the foothills of the southern Cantabrian Mountains, nearby Villaseca de Laciana (León,NWIberian Peninsula). This lake has a glacier origin and has been formed due to the obstruction of a lateral moraine of the glacier tongue that will be canalized through the Valley of Brañas de Roble. Once discovered during the Late Glacial (over 23,000 years), the linle basin beganto work as a catchment area. A 893 cm length record has been srudied. Ir shows the postglacial evolution of the lake. Most part of this record (beteween 260-893 cm) is represented by a detritic varved sedimentation, where the absence of diatoms is clear, although the pollen record is continous all through the sequence. In this period, the paleolimnological reconstruction can't be done, because the grains of pollen in the sediment proceed from an alloctonous source and they only reflect the landscape in the surroundings of the lake. With the begining of the Late Glacial the lake of Villaseca began to present an autoctonous diatom flora and the basin changed to mesotrophic and slightly alkaline conditions. The most important data proceed from the study of the diatoms succession, which points out and environment dominated by tychoplanktonic Fragilaria assemblages, only interrupted by a period ofperiphytic, acidophilous and oligotrophic assemblages. During this episode the pollen record points out a stepic vegetation, represented by Artemisia and Poaceae. During the Postglacial, the basin becomes completely filled and the number of acidophilous taxa increase. This is a typical final step of the filling process ofa lake before transforming into a bog as the presence of Sphagnum establishes
Immunoteràpia, un concepte clàssic amb novetats rellevants: els biològics i la immunoteràpia antitumoral com a exemples concrets
De la inducció de memòria immunitària de les vacunes antiinfeccioses, a la immunoteràpia cel·lular i genètica per al tractament de tumors, el ventall de teràpies potencials a través de la modulació del sistema immunitari és una de les aproximacions més prometedores que el coneixement basat en la immunologia ha fet, fa i farà realitat. Els avenços són constants i els resultats obtinguts en aquests primers anys del segle XXI situen la immunoteràpia entre les àrees mèdiques amb més potencialitat de tractament. En aquesta revisió ens centrarem en alguns dels avenços més rellevants dels tractaments basats en fàrmacs biològics (principalment anticossos), així com en els canvis introduïts en el tractament del càncer a través de la manipulació de la resposta immunitària.From the induction of immunological memory with anti-infectious vaccines through cell and gene immunotherapy to tumour treatments, the range of potential therapies stemming from modulation of the immune system is one of the most promising areas of immunology-based knowledge. Developments are constant and the results obtained during the early 21st century have placed immunotherapy among the areas with the greatest potential for clinical treatment. In this review, we focus on some of the biggest developments in treatment based on biological drugs (mainly antibodies) and, particularly, the progress made in the treatment of cancer by manipulating immune responses against tumour
Un exemple de col·laboració entre diferents institucions per afavorir la divulgació científica en català: el llibre Els misteris del sistema immunitari
Barcelona conference on epigenetics and cancer: 50 years of histone acetylation
The Barcelona Conference on Epigenetics and Cancer (BCEC) was held in Barcelona, Spain, on October 1 and 2 , 2014. The meeting was co-organized by the Cancer Epigenetics and Biology Program (PEBC-IDIBELL) and B·Debate, an initiative of Biocat, with the support of 'la Caixa' Foundation. The scientific committee was comprised of leading scientists in the field of epigenetics: Dr. Manel Esteller, director of PEBC-IDIBELL, Dr. Alejandro Vaquero and Dr. Esteban Ballestar, from PEBC-IDIBELL, Juan Ausió from the University of Victoria (Canada), and Marcus Buschbeck, from the Institute of Predictive and Personalized Medicine of Cancer (IMPPC), as BCEC series coordinator. This meeting was the second edition of the BCEC series, which was launched by 5 leading Barcelonan institutes to bring together leading investigators in the fields of epigenetics and chromatin research. The topics discussed during the meeting included the current challenges, opportunities, and perspectives surrounding the study of histone modifications (focusing in acetylation), chromatin structure and gene expression, and the involvement of histone acetylation in physiology and diseases, such as cancer or neurological diseases
Instilling moral value alignment by means of multi-objective reinforcement learning
AI research is being challenged with ensuring that autonomous agents learn to behave ethically, namely in alignment with moral values. Here, we propose a novel way of tackling the value alignment problem as a two-step process. The first step consists on formalising moral values and value aligned behaviour based on philosophical foundations. Our formalisation is compatible with the framework of (Multi-Objective) Reinforcement Learning, to ease the handling of an agent's individual and ethical objectives. The second step consists in designing an environment wherein an agent learns to behave ethically while pursuing its individual objective. We leverage on our theoretical results to introduce an algorithm that automates our two-step approach. In the cases where value-aligned behaviour is possible, our algorithm produces a learning environment for the agent wherein it will learn a value-aligned behaviour
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