997 resultados para p-rational belief system
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We extend Aumann's theorem [Aumann 1987], deriving correlated equilibria as a consequence of common priors and common knowledge of rationality, by explicitly allowing for non-rational behavior. Wereplace the assumption of common knowledge of rationality with a substantially weaker one, joint p-belief of rationality, where agents believe the other agents are rational with probability p or more. We show that behavior in this case constitutes a kind of correlated equilibrium satisfying certain p-belief constraints, and that it varies continuously in the parameters p and, for p sufficiently close to one,with high probability is supported on strategies that survive the iterated elimination of strictly dominated strategies. Finally, we extend the analysis to characterizing rational expectations of interimtypes, to games of incomplete information, as well as to the case of non-common priors.
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En este estudio, intento resumir los debates relacionados con la última cultura paleoesquimal de Canadá Ártica y la de Groenlandia, y llamar la atención sobre las analogías culturales desde Asia, además de crear un cuadro complejo sobre el chamanismo y el culto al oso de los Dorset. Los temas como el origen del arte de los Dorset, la transición Pre-Dorset-Dorset, y los contactos entre los Dorset y los Thule son relevantes para reconstruir el sistema de creencias de los Dorset. Sin embargo, la totalidad del sistema de creencias de los paleoesquimales no se puede comprender sobre la base de los hallazgos arqueológicosy las analogías etnográficas remotas.
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Glasses having the composition As2S3(1-x)-P2S5(x) with x ranging from 0 to 0.7 have been investigated to determine the compositional effect on properties and local structure. Glass transition temperature (T,) decreases and molar volume (V,,) increases with an increase in P content. Using P-31 NMR, we measured the strength of the P-31-P-31 magnetic dipolar interaction in the glass samples and the AsPS4 crystallized phase. Based on these data, we observed the formation of the As2P2S8 network, which reflects an increase in the average coordination number and a decrease in the degree of rigidity.
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This paper presents an approach to the belief system based on a computational framework in three levels: first, the logic level with the definition of binary local rules, second, the arithmetic level with the definition of recursive functions and finally the behavioural level with the definition of a recursive construction pattern. Social communication is achieved when different beliefs are expressed, modified, propagated and shared through social nets. This approach is useful to mimic the belief system because the defined functions provide different ways to process the same incoming information as well as a means to propagate it. Our model also provides a means to cross different beliefs so, any incoming information can be processed many times by the same or different functions as it occurs is social nets.
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In this article we present a model of organization of a belief system based on a set of binary recursive functions that characterize the dynamic context that modifies the beliefs. The initial beliefs are modeled by a set of two-bit words that grow, update, and generate other beliefs as the different experiences of the dynamic context appear. Reason is presented as an emergent effect of the experience on the beliefs. The system presents a layered structure that allows a functional organization of the belief system. Our approach seems suitable to model different ways of thinking and to apply to different realistic scenarios such as ideologies.
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Includes bibliography.
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RESUMO: INTRODUÇÃO: A OMS (2001) revela que cerca de 450 milhões de pessoas sofrem de perturbações mentais ou comportamentais em todo o mundo, mas apenas uma pequena minoria tem tratamento, ainda que elementar. Transformam-se em vítimas por causa da sua doença e convertem-se em alvos de estigma e discriminação. O suicídio é considerado como um grande problema de saúde pública em todo o mundo, é uma das principais causas de morte de jovens adultos e situa-se entre as três maiores causas de morte na população entre 15-34 anos (OMS, 2001). As perturbações mentais aumentam o risco de suicídio. A depressão, esquizofrenia, e a utilização de substâncias incrementam o risco de suicídio. Estudos (Sartorius, 2002; Magliano et al., 2012) mostram que os profissionais de saúde, tal como o público em geral, podem ter atitudes negativas e estigma em relação às pessoas com perturbações mentais, podendo agir em conformidade, uma vez feito e conhecido o diagnóstico psiquiátrico. Os clínicos gerais são os receptores das perturbações mentais e tentativas de suicídio nas principais portas de entrada no acesso a cuidados de saúde. As crenças, conhecimentos e contacto com a doença mental e o suicídio, podem influenciar a atenção clínica. OBJECTIVOS: Avaliar o estigma e as percepções dos médicos de clínica geral em relação às tentativas de suicídio, o suicídio e perturbações mentais bem como os possíveis factores associados a estes fenómenos. MATERIAIS E MÉTODOS: Estudo do tipo transversal, combinando métodos quantitativos e qualitativos. A amostra é constituída por 125 sujeitos, médicos de clínica geral. Utilizaram-se as versões adaptadas dos seguintes instrumentos: Questionário sobre Percepções e Estigma em Relação à Saúde Mental e ao Suicídio (Liz Macmin e SOQ, Domino, 2005) e a Escala de Atitudes sobre a Doença Mental (Amanha Hahn, 2002). Para o tratamento estatístico dos dados usou-se a estatística 1) descritiva e 2) Análise estatística das hipóteses formuladas (Qui Quadrado - 2) a correlação entre variáveis (Spearman: ρ, rho). Os dados conectados foram limpos de inconsistências com base no pacote informático e estatístico SPSS versão 20. Para a aferição da consistência interna foi usado o teste de Alfa de Cronbach. RESULTADOS: Uma boa parte da amostra (46.4%) refere que não teve formação formal ou informal em saúde mental e (69.35%) rejeitam a ideia de que “grupos profissionais como médicos, dentistas e psicólogos são mais susceptíveis a cometer o suicídio”. Já (28.0%) têm uma perspectiva pessimista quanto a possibilidade de recuperação total dos sujeitos com perturbação mental. Sessenta e oito(54.4%) associa sujeitos com perturbação mental, a comportamentos estranhos e imprevisíveis, 115 (92.0%) a um baixo QI e 35 (26.7%) a poderem ser violentas e e perigosas. Os dados mostram uma associação estatisticamente significativa (p0.001) entre as variáveis: tempo de serviço no SNS, recear estar perto de sujeitos com doença mental e achar que os sujeitos com doença mental são mais perigosos que outros. Em termos estatísticos, existe uma associação estatitisticamente significativa entre as duas variáveis(X2=9,522; p0.05): percepção de que “é vergonhoso ter uma doença mental” e os conhecimentos em relação à doença mental. Existe uma correlação positiva, fraca e estatisticamente significativa entre os conhecimentos dos clínicos gerais(beneficiar-se de formação em saúde mental) e a percepção sobre os factores de risco (0,187; P0,039). DISCUSSÃO E CONCLUSÕES: A falta de conhecimento sobre as causas e factores de risco para os comportamentos suicidários, opções de intervenção e tratamento, particularmente no âmbito da doença mental, podem limitar a procura de ajuda individual ou dos próximos. Percepções negativas como o facto de não merecerem prioridade nos serviços, mitos (frágeis e cobarde, sempre impulsivo, chamadas de atenção, problemas espirituais) podem constituir-se como um indicador de que os clínicos gerais podem sofrer do mesmo sistema de estigma e crenças, de que sofre o público em geral, podendo agir em conformidade (atitudes de afastamento ereceio). As atitudes são influenciadas por factores como a formação, cultura e sistema de crenças. Sujeitos com boa formação na área da saúde mental têm uma percepção positiva e optimista sobre os factores de risco e uma atitude positiva em relação aos sujeitos com doença mental e comportamentos suicidários.-------------ABSTRACT: INTRODUCTION: The WHO (2001) reveals that about 450 million people suffer from mental or behavioral disorders worldwide, but only a small minority have access to treatment, though elementary. They become victims because of their disease and they become the targets of stigma and discrimination. Suicide is seen as a major public health problem worldwide, is a leading cause of death for young adults and is included among the three major causes of death in the population aged 15-34 years (WHO, 2001). Mental disorders increase the risk of suicide. Depression, schizophrenia, and the substances misuse increase the risk of suicide. Studies (Sartorius, 2002; Magliano et al, 2012) show that health professionals, such as the general public, may have negative attitudes and stigma towards people with mental disorders, and can act accordingly after psychiatric diagnosis is known. General practitioners are the main entry points of mental disorders and suicide attempts in the health sistem. Beliefs, knowledge and contact with mental illness and suicide, may influence clinical care. OBJECTIVES: To assess stigma and perceptions of general practitioners in relation to suicide attempts, suicide and mental disorders as well as possible factors associated with these phenomena. MATERIAL AND METHODS: This was a descriptive cross-sectional study, combining quantitative and qualitative methods. The sample consisted of 125 subjects, general practitioners. We used adapted versions of the following instruments: Questionnaire of Perceptions and Stigma in Relation to Mental Health and Suicide (Liz Macmin and SOQ, Domino, 2005) and the Scale of Attitudes on Mental Illness (Tomorrow Hahn, 2002). For the statistical treatment of the data we used: 1) descriptive (Data distribution by absolute and relative frequencies for each of the variables under study (including mean and standard deviation measures of central tendency and deviation), 2) statistical analysis of hypotheses using (Chi Square - 2, a hypothesis test that is intended to find a value of dispersion for two nominal variables, evaluating the association between qualitative variables) and the correlation between variables (Spearman ρ, rho), a measure of non-parametric correlation, which evaluates an arbitrary monotonic function can be the description of the relationship between two variables, without making any assumptions about the frequency distribution of the variables). For statistical analysis of the correlations were eliminated subjects who did not respond to questions. The collected data were cleaned for inconsistencies based on computer and statistical package SPSS version 20. To measure the internal consistency was used the Cronbach's alpha test. RESULTS: A significant part of the sample 64 (46.4%) reported no formal or informal training in mental health and 86 (69.35%) reject the idea that "professional groups such as doctors, dentists and psychologists are more likely to commit suicide." On the other hand, 42 (28.0%) have a pessimistic view of the possibility of full recovery of individuals with mental disorder. Sixty-eight ( 54.4 % ) of them associates subjects with mental disorder to strange and unpredictable behavior, 115 ( 92.0 % ), to low IQ, 35 ( 26.7 % ) and even to violent and dangerous behavior, 78 ( 62.4 % ) The data show a statistically significant (p = 0.001) relationship between the following variables: length of service in the NHS, fear of being close to individuals with mental illness and considering individuals with mental illness more dangerous than others. In statistical terms, there is a dependency between the two variables (X2 = 9.522, p> 0.05): the perception that "it is shameful to have a mental illness" and knowledge regarding mental illness. There is a positive and statistically significant weak correlation between knowledge of general practitioners (benefit from mental health training) and the perception of the risk factors (0,187; P0,039). DISCUSSION AND CONCLUSIONS: The lack of knowledge about the causes and risk factors for suicidal behavior, intervention and treatment, particularly in the context of mental illness options, may decreaseseeking for help by individual and their relatives. Negative perceptions such as considering that they dont deserve priority in services, myths (weak and cowards, always impulsive, seeking for attentions, spirituals problems) may indicate that general practitioners, may suffer the same stigma and beliefs systems as the general public, and can act accordingly (withdrawal and fear attitudes). Attitudes are influenced by factors such as education, culture and belief system. Subjects with good training in mental health have a positive and optimistic perception of the risk factors and a positiveattitude towards individuals with mental illness and suicidal behaviour.
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BACKGROUND: An LC-MS/MS method has been developed for the simultaneous quantification of P-glycoprotein (P-gp) and cytochrome P450 (CYP) probe substrates and their Phase I metabolites in DBS and plasma. P-gp (fexofenadine) and CYP-specific substrates (caffeine for CYP1A2, bupropion for CYP2B6, flurbiprofen for CYP2C9, omeprazole for CYP2C19, dextromethorphan for CYP2D6 and midazolam for CYP3A4) and their metabolites were extracted from DBS (10 µl) using methanol. Analytes were separated on a reversed-phase LC column followed by SRM detection within a 6 min run time. RESULTS: The method was fully validated over the expected clinical concentration range for all substances tested, in both DBS and plasma. The method has been successfully applied to a PK study where healthy male volunteers received a low dose cocktail of the here described P-gp and CYP probes. Good correlation was observed between capillary DBS and venous plasma drug concentrations. CONCLUSION: Due to its low-invasiveness, simple sample collection and minimal sample preparation, DBS represents a suitable method to simultaneously monitor in vivo activities of P-gp and CYP.
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The role of cytochrome P450 in the metabolism of dextromethorphan, amitriptyline, midazolam, S-mephenytoin, citalopram, fluoxetine and sertraline was investigated in rat and human brain microsomes. Depending on the parameters, the limit of quantification using gas chromatography-mass spectrometry methods was between 1.6 and 20 pmol per incubation, which generally contained 1500 microg protein. Amitriptyline was shown to be demethylated to nortriptyline by both rat and human microsomes. Inhibition studies using ketoconazole, furafylline, sulfaphenazole, omeprazole and quinidine suggested that CYP3A4 is the isoform responsible for this reaction whereas CYP1A2, CYP2C9, CYP2C19 and CYP2D6 do not seem to be involved. This result was confirmed by using a monoclonal antibody against CYP3A4. Dextromethorphan was metabolized to dextrorphan in rat brain microsomes and was inhibited by quinidine and by a polyclonal antibody against CYP2D6. Only the addition of exogenous reductase allowed the measurement of this activity in human brain microsomes. Metabolites of the other substrates could not be detected, possibly due to an insufficiently sensitive method. It is concluded that cytochrome P450 activity in the brain is very low, but that psychotropic drugs could undergo a local cerebral metabolism which could have pharmacological and/or toxicological consequences.
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Genetic polymorphisms have currently been described in more than 200 systems affecting pharmacological responses (cytochromes P450, conjugation enzymes, transporters, receptors, effectors of response, protection mechanisms, determinants of immunity). Pharmacogenetic testing, i.e. the profiling of individual patients for such variations, is about to become largely available. Recent progress in the pharmacogenetics of tamoxifen, oral anticoagulants and anti-HIV agents is reviewed to discuss critically their potential impact on prescription and contribution/limits for improving rational and safe use of pharmaceuticals. Prospective controlled trials are required to evaluate large-scale pharmacogenetic testing in therapeutics. Ethical, social and psychological issues deserve particular attention.
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The suitability of the capillary dried blood spot (DBS) sampling method was assessed for simultaneous phenotyping of cytochrome P450 (CYP) enzymes and P-glycoprotein (P-gp) using a cocktail approach. Ten volunteers received an oral cocktail capsule containing low doses of the probes bupropion (CYP2B6), flurbiprofen (CYP2C9), omeprazole (CYP2C19), dextromethorphan (CYP2D6), midazolam (CYP3A), and fexofenadine (P-gp) with coffee/Coke (CYP1A2) on four occasions. They received the cocktail alone (session 1), and with the CYP inhibitors fluvoxamine and voriconazole (session 2) and quinidine (session 3). In session 4, subjects received the cocktail after a 7-day pretreatment with the inducer rifampicin. The concentrations of probes/metabolites were determined in DBS and plasma using a single liquid chromatography-tandem mass spectrometry method. The pharmacokinetic profiles of the drugs were comparable in DBS and plasma. Important modulation of CYP and P-gp activities was observed in the presence of inhibitors and the inducer. Minimally invasive one- and three-point (at 2, 3, and 6 h) DBS-sampling methods were found to reliably reflect CYP and P-gp activities at each session.
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BACKGROUND: A packed bed bioreactor (PBBR) activated with an indigenous nitrifying bacterial consortia was developed and commercialized for rapid establishment of nitrification in brackish water and marine hatchery systems in the tropics. The present study evaluated nitrification in PBBR integrated into a Penaeus monodon recirculating maturation system under different substrate concentrations and flow rates. RESULTS:Instantnitrificationwasobservedafter integration ofPBBRinto thematuration system.TANandNO2-Nconcentrations were always maintained below0.5 mg L−1 during operation. The TANandNO2-N removalwas significant (P < 0.001) in all the six reactor compartments of the PBBR having the substrates at initial concentrations of 2, 5 and 10 mg L−1. The average volumetric TAN removal rates increased with flow rates from 43.51 (250 L h−1) to 130.44 (2500 L h−1) gTAN m−3 day−1 (P < 0.05). FISH analysis of the biofilms after 70 days of operation gave positive results with probes NSO 190 ((β ammonia oxidizers), NsV 443 (Nitrosospira spp.) NEU (halophilic Nitrosomonas), Ntspa 712 (Phylum Nitrospira) indicating stability of the consortia. CONCLUSION: The PBBR integrated into the P. monodon maturation system exhibited significant nitrification upon operation for 70 days as well as at different substrate concentrations and flow rates. This system can easily be integrated into marine and brackish water aquaculture systems, to establish instantaneous nitrification
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El terrorismo en la actualidad es considerado como uno de los conceptos más controversiales en los campos social, académico y político. El término se empieza a utilizar después de la Revolución Francesa, pero recientemente, a raíz de los atentados del 11 de septiembre de 2001, ha tomado suma relevancia y ha motivado numerosas investigaciones para tratar de entender qué es terrorismo. Aunque a la fecha existen varias revisiones sistemáticas, este trabajo tiene como propósito revisar, agrupar y concretar diferentes teorías y conceptos formulados por los autores que han trabajado sobre el concepto de “terrorismo” con el fin de entender las implicaciones de su utilización en el discurso, y cómo esto afecta la dinámica interna de las sociedades en relación con la violencia, las creencias, los estereotipos entre otros elementos. Para lograrlo, se revisaron 56 artículos, publicados entre los años 1985 y 2013; 10 fuentes secundarias entre noticias y artículos de periódicos correspondientes a los años 1995-2013 y 10 estudios estadísticos cuyos resultados nos aportan a la comprensión del tema en cuestión. La búsqueda se limitó al desarrollo histórico del terrorismo, sus diferentes dimensiones y el concepto social de la realidad de terrorismo. Los hallazgos demuestran que la palabra “terrorismo” constituye un concepto que como tal es un vehículo lingüístico que puede ser utilizado con fines, estratégicos movilizando al público conforme a través del discurso e intereses políticos, destacando la necesidad de estudiar las implicaciones psicológicas y sociales de su uso.