406 research outputs found
Games on Cellular Spaces: How Mobility Affects Equilibrium
In this work we propose a new model for spatial games. We present a definition of mobility in terms of the satisfaction an agent has with its spatial location. Agents compete for space through a non-cooperative game by using mixed strategies. We are particularly interested in studyig the relation between Nash equilibrium and the winner strategy of a given model with mobility, and how the mobility can affect the results. The experiments show that mobility is an important variable concerning spatial games. When we change parameters that affect mobility, it may lead to the success of strategies away from Nash equilibrium.Spatial Games, Agent-Based Modelling, Mobility, Satisfaction, Chicken Game, Nash Equilibrium
Climate change impact on flood hazard in a central Portugal alluvial plain
Paper Abstract
This paper presents the flood hazard projections under climate change scenarios, for a period between 2021 and 2050, in the Lis river alluvial plain located at the Centre of Portugal. Furthermore, the paper also aim at understanding the hydrological processes in the study area by coupling a hydrological (HEC – HMS) and hydrodynamic model (HEC – RAS). The Lis river basin is becoming more favourable to the production of high water flows, due to the increase of impervious areas and deforestation which have reduced the time concentration on the river basin, empowering flood events with high flood peaks and water flood levels with serious consequences for the facilities (pumping stations, centre pivots) and infrastructures (irrigation networks and roads) in the alluvial plain. The methodology was developed using the daily outputs of the ALADIN and HIRHAM from the EURO-CORDEX project with a 12.5 km horizontal resolution for the RCP4.5 scenario and coupled calibrated hydrological– hydrodynamic models. The results indicated that the annual rainfall would vary for the ALADIN model between a decrease of -24% and an increase of 22% and for the HIRHAM model between a decrease of -85% and an increase of 24%. The results also projected increases in higher runoffs and water level under future climate change scenarios. The HIRHAM model was considered unsuitable for flood impact assessment
Preparation of carbon molecular sieve membranes from an optimized ionic liquid-regenerated cellulose precursor
Novel carbon molecular sieve membranes with high separation performance and stability in the presence of humidified streams were prepared from an optimized ionic liquid-regenerated cellulose precursor, in a single carbonization step. Membranes prepared at two different carbonization end temperatures (550 degrees C and 600 degrees C) were analyzed through scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, carbon dioxide adsorption and permeation experiments. The prepared membranes exhibited uniform thickness of approximately 20 mu m and a well-developed microporous structure. The permeation performance of these carbon molecular sieve membranes was above the Robeson upper bound curve for polymeric membranes. In particular, the membrane prepared at 550 degrees C end temperature exhibited permeability to oxygen of 5.16 barrer and O-2/N-2 ideal selectivity of 32.3 and permeability to helium of 126 barrer and He/N-2 ideal selectivity of 788; besides, permeation experiments performed in the presence of ca. 80% relative humidity showed that humidity does not originate pore blockage. These results open the door for the preparation of tailor made precursors that originate carbon molecular sieve membranes with extraordinary separation performances, mechanical resistance and stability
Production of Melanin Pigment by Fungi and Its Biotechnological Applications
Production of the microbial pigments is one of the emerging fields of research due to a growing interest of the industry for safer products, easily degradable and eco-friendly. Fungi constitute a valuable source of pigments because they are capable of producing high yields of the substance in the cheap culture medium, making the bioprocess economically viable on the industrial scale. Some fungal species produce a dark-brown pigment, known as melanin, by oxidative polymerization of phenolic compounds, such as glutaminyl-3,4-dihydroxybenzene (GDHB) or catechol or 1,8-dihydroxynaphthalene (DHN) or 3,4-dihydroxyphenylalanine (DOPA). This pigment has been reported to act as “fungal armor” due to its ability to protect fungi from adverse conditions, neutralizing oxidants generated in response to stress. Apart from the scavenging activity, melanin exhibits other biological activities, including thermoregulatory, radio- and photoprotective, antimicrobial, antiviral, cytotoxic, anti-inflammatory, and immunomodulatory. Studies have shown that the media composition and cultivation conditions affect the pigment production in fungi and the manipulation of these parameters can result in an increase in pigment yield for large-scale pigment production. This chapter presents a comprehensive discussion of the research on fungal melanin, including the recently discovered biological activities and the potential use of this pigment for various biotechnological applications in the fields of biomedicine, dermocosmetics, materials science, and nanotechnology
Rare earth element and yttrium geochemistry applied to the genetic study of cryolite ore at the Pitinga Mine (Amazon, Brazil)
This work aims at the geochemical study of Pitinga cryolite mineralization through REE and Y analyses in disseminated and massive cryolite ore deposits, as well as in fluorite occurrences. REE signatures in fluorite and cryolite are similar to those in the Madeira albite granite. The highest ΣREE values are found in magmatic cryolite (677 to 1345 ppm); ΣREE is lower in massive cryolite. Average values for the different cryolite types are 10.3 ppm, 6.66 ppm and 8.38 ppm (for nucleated, caramel and white types, respectively). Disseminated fluorite displays higher ΣREE values (1708 and 1526ppm) than fluorite in late veins(34.81ppm). Yttrium concentration is higher in disseminated fluorite and in magmatic cryolite. The evolution of several parameters (REEtotal, LREE/HREE, Y) was followed throughout successive stages of evolution in albite granites and associated mineralization. At the end of the process, late cryolite was formed with low REEtotal content. REE data indicate that the MCD was formed by, and the disseminated ore enriched by (additional formation of hydrothermal disseminated cryolite), hydrothermal fluids, residual from albite granite. The presence of tetrads is poorly defined, although nucleated, caramel and white cryolite types show evidence for tetrad effect.Este trabalho enfoca a geoquímica de elementos terras raras (ETR) e de Y no minério criolítico disseminado, no depósito criolítico maciço e na fluorita associada na mina Pitinga. As assinaturas de ETR na criolita e fluorita são similares àquelas do granito Madeira. Os maiores valores de SETR são encontrados na criolita magmática disseminada (677 a 1.345 ppm); SETR é menor na criolita maciça, com valores médios de 10,3 ppm, 6,66 ppm e 8,38 ppm, respectivamente, nos tipos de criolita nucleada, caramelo e branca. A fluorita magmática disseminada apresenta os valores mais altos de SETR (1.708 e 1.526 ppm), contrastando com a fluorita de veio tardio(34,81 ppm). A concentração de Y é maior na fluorita disseminada e na criolita magmática. As evoluções de diversos parâmetros (SETR, ETRL/ETRP, Y) podem ser seguidas através dos sucessivos estágios de evolução dos albita granitos e mineralização associada. Os dados de ETR indicam que o depósito criolítico maciço foi formado por, e o minério disseminado enriquecido por (formação adicional criolita disseminada hidrotermal), fluidos hidrotermais residuais do albita granito. A presença do efeito tetrad não é bem definida, embora as criolitas maciças nucleada, caramelo e branca apresentem algumas evidências deste efeito.FINEPAgência para o Desenvolvimento da Indústria Mineral do BrasilConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) - Departamento Nacional de Produção MineralFundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) - Programa de Apoio a Núcleos de ExcelênciaCNP
Brazilian guideline for the treatment of patients with opioids dependence syndrome
There is a relatively low prevalence of opioid use in Brazil, particularly involving the non-medical use of codeine and opiate-containing syrups. However, opioid dependence syndrome shows a significant total impact on mortality and morbidity. Over the past 20 years, scientific progress has changed our understanding of the nature of opioid addiction and its various possible treatments. Addiction is a chronic illness treatable if the treatment is well-delivered and tailored to the needs of the particular patient. There is indeed an array of treatments that can effectively reduce drug use, help manage drug cravings, prevent relapses and restore people to productive social functioning. The treatment of drug addiction will be part of long-term, medical, psychological, and social perspectives. This guideline aims at providing guidance to psychiatrists and other mental health professionals who care for patients with Opioid Dependence Syndrome. It comments on the somatic and psychosocial treatment that is used for such patients, and reviews scientific evidences and their strength. Also, the essential historical, epidemiological and neurobiological aspects of Opioid Dependence are reviewed.Existe uma prevalência relativamente baixa do uso de ópioides no Brasil, em particular envolvendo o uso não médico da codeína e de xaropes que contêm opióides. No entanto, a síndrome de dependência apresenta um significativo impacto total na mortalidade e morbidade. Nos últimos 20 anos, o avanço científico tem modificado nosso entendimento sobre a natureza da adição aos opióides e os variados tratamentos possíveis. A adição é uma doença crônica tratável se o tratamento for realizado e adaptado tendo em vista as necessidades do paciente específico. Há, de um fato, um conjunto de tratamentos que podem efetivamente reduzir o uso da droga, ajudar a gerenciar a fissura pela droga, prevenir recaídas e recuperar as pessoas para o funcionamento social produtivo. O tratamento da dependência de drogas será parte de perspectivas de longo prazo do ponto de vista médico, psicológico e social. Esta diretriz almeja fornecer um guia para os psiquiatras e outros profissionais de saúde que tratam de pacientes com Síndrome de Dependência de Opióides. Ela tece comentários sobre o tratamento somático e psicossocial que é utilizado nesses pacientes e revisa as evidências científicas e seu poder. Da mesma forma, os aspectos históricos, epidemiológicos e neurobiológicos da dependência de opióides são revisados.Universidade de São Paulo Hospital de Clínicas Instituto de PsiquiatriaFaculdade de Medicina do ABCJohns Hopkins University School of MedicineAssociação Brasileira de Psiquiatria Departamento de Dependência QuímicaHospital Albert EinsteinUniversidade Federal de São Paulo (UNIFESP)UNIADUNIFESPSciEL
Trypanosoma Cruzi: Parasite Persistence In Tissues In Chronic Chagasic Brazilian Patients.
Chagas disease in the chronic phase may develop into cardiac and/or digestive forms. The pathogenesis of the disease is not yet clear and studies have been carried out to elucidate the role of parasite persistence in affected organs. The aim of this study was to detect and quantify Trypanosoma cruzi in paraffin-embedded tissue samples from chronic patients using NPCR (nested polymerase chain reaction) and QPCR (quantitative polymerase chain reaction) methods. These results were correlated to anatomopathological alterations in the heart and gastrointestinal tract (GIT). Of the 23 patients studied, 18 presented the cardiac form and five presented the cardiodigestive form of Chagas disease. DNA samples were randomly isolated from formalin-fixed paraffin-embedded sections of heart and GIT tissue of 23 necropsies and were analyzed through NPCR amplification. T. cruzi DNA was detected by NPCR in 48/56 (85.7%) heart and 35/42 (83.3%) GIT samples from patients with the cardiac form. For patients with the cardiodigestive form, NPCR was positive in 12/14 (85.7%) heart and in 14/14 (100%) GIT samples. QPCR, with an efficiency of 97.6%, was performed in 13 samples (11 from cardiac and 2 from cardiodigestive form) identified previously as positive by NPCR. The number of T. cruzi copies was compared to heart weight and no statistical significance was observed. Additionally, we compared the number of copies in different tissues (both heart and GIT) in six samples from the cardiac form and two samples from the cardiodigestive form. The parasite load observed was proportionally higher in heart tissues from patients with the cardiac form. These results show that the presence of the parasite in tissues is essential to Chagas disease pathogenesis.10685-9
The health and socio-demographic factors associated with depressive symptoms during the COVID-19 pandemic:A cross-sectional study
Introduction: Our objective was to analyze depressive symptoms during the COVID‐19 pandemic and their association with health and sociodemographic factors.
Methods: A survey of 4203 adults from ten municipalities was conducted in Mato Grosso state, Amazon region of Brazil. Data collection was done at home, with the collection of sociodemographic characteristics, and aspects of both physical and mental health. The DSM‐5 level 1 cross‐sectional symptom scale was used to identify symptoms of depression, substance use disorders, sleep disturbances, and anxiety. Chemiluminescence was also used to detect IgG anti‐SARS‐CoV‐2 antibodies.
Results: The estimated prevalence of anti‐SARS‐CoV‐2 antibodies was 12.5% and the prevalence of depressive symptoms was 23.2%. In the multivariate analysis, depression was associated with being male, having a low income, the level of physical activity before the pandemic, chronic illness, substance use disorder, sleep and anxiety disorders.
Conclusion: Evidence on depression and its associated factors is critical to understanding the extent of the population situation from which recommendations can be made to guide public policy.Introdução: O nosso objetivo foi analisar a associação entre sintomas depressivos e fatores sociodemográficos e de saúde durante a pandemia de COVID‐19.
Métodos: Foi realizado um estudo com 4203 adultos de dez municípios do estado de Mato Grosso, região amazônica do Brasil. A recolha de dados foi realizada na residência, com levantamento de informações sobre as características sociodemográficas, aspectos de saúde física e mental. A Escala de Sintomas Transversais de Nível 1 do DSM‐5 foi utilizada para identificar sintomas de depressão, transtorno por uso de substâncias, distúrbios do sono e ansiedade. A quimiluminescência foi utilizada para detectar anticorpos IgG anti‐SARS‐CoV‐2.
Resultados: A prevalência estimada de anticorpos anti‐SARS‐CoV‐2 foi de 12,5% e a prevalência de sintomas depressivos foi de 23,2%. Na análise multivariada, a depressão esteve associada a ser do sexo masculino, ter baixa renda, nível de atividade física antes da pandemia, ter doença crónica, apresentar transtorno por uso de substâncias, transtornos do sono e de ansiedade.
Conclusão: Os achados sobre a depressão e seus fatores associados são essenciais para a compreensão sobre a magnitude do quadro desses sintomas na população, a partir de onde podem ser feitas recomendações que norteiem as políticas públicas
Incidência e preditores de gestação em mulheres com HIV/Aids no Rio de Janeiro
OBJETIVO: Identificar incidencia y predictores de la primera gestación entre mujeres con VIH/Sida. MÉTODOS: Estudio prospectivo de cohorte conducido en Rio de Janeiro, Sureste de Brasil, entre 1996 y 2003. El estudio incluyó 225 mujeres acompañadas hasta la primera gestación o hasta el primer evento considerado censura (histerectomía, ligadura tubárica, menopausia, 50 años de edad, pérdida de acompañamiento, óbito o final de diciembre de 2003). Se estimaron las tasas de incidencia de gestación y de aborto, y se usaron modelos de riesgos proporcionales de Cox para identificar las características de la visita de inclusión asociadas con el riesgo de gestación. RESULTADOS: Las mujeres fueron acompañadas por 565 persona/años, con promedio de acompañamiento de 3 años por mujer. La edad promedio fue de 32 años (DP:7), y 54,7% eran blancas. Sesenta gestaciones fueron observadas en 39 mujeres y 18 resultaron en abortos inducidos (tasas de incidencia de 6,9% y 2,1% mujeres/año, respectivamente). Las gestaciones repetidas ocurrieron en 33,3% de las mujeres (13/39). Fue observado el mayor riesgo de gestación entre mujeres jóvenes (HR=3,42; IC 95%:1,69;6,95) y entre aquellas que vivían con sus parejas (HR=1,89; IC 95%: 1,00;3,57). El menor riesgo de gestación estuvo asociado a la mayor escolaridad (HR=0,43; IC95%:0,19;0,99) y al uso de terapia antirretroviral (HR=0,61; IC95%:0,31;1,17). CONCLUSIONES: La incidencia de gestación en la cohorte fue menor al compararse con aquella observada en la población general. Características sociodemográficas deben ser consideradas en el manejo de los deseos reproductivos de mujeres VIH-positivas en edad reproductiva. Los programas de VIH/SIDA deben incluir consejos reproductivos y contraceptivos para prevenir la transmisión del VIH para sus parejas y prole.OBJETIVO: Identificar incidência e preditores incidência da primeira gestação entre mulheres com HIV/Aids. MÉTODOS: Estudo prospectivo de coorte conduzido entre 1996 e 2003 no Rio de Janeiro, RJ, com 225 mulheres acompanhadas até a primeira gestação ou até o primeiro evento considerado censura (histerectomia, ligadura tubárea, menopausa, 50 anos de idade, perda de acompanhamento, óbito ou final de dezembro de 2003). Taxas de incidência de gestação e de aborto foram estimadas e modelos de riscos proporcionais de Cox foram usados para identificar as características da visita de inclusão associadas com o risco de gestação. RESULTADOS: As mulheres foram acompanhadas por 565 pessoas/ano, com média de acompanhamento de 3 anos por mulher. A idade média foi de 32 anos (DP: 7) e 54,7% eram brancas. Sessenta gestações foram observadas em 39 mulheres e 18 resultaram em abortos induzidos (taxas de incidência de 6,9% e 2,1% mulheres/ano, respectivamente). Gestações repetidas ocorreram em 33,3% das mulheres (13/39). Maior risco de gestação foi observado entre mulheres jovens (HR = 3,42; IC95%:1,69;6,95) e entre aquelas vivendo com seus parceiros (HR = 1,89; IC95%:1,00;3,57). Menor risco de gestação esteve associado à maior escolaridade (HR = 0,43; IC95%:0,19;0,99) e ao uso de terapia anti-retroviral (HR = 0,61; IC95%:0,31;1,17). CONCLUSÕES: A incidência de gestação na coorte foi menor se comparada àquela observada na população geral. Características sociodemográficas devem ser consideradas no manejo dos desejos reprodutivos de mulheres HIV-positivas em idade reprodutiva. Os programas de HIV/Aids devem incluir aconselhamento reprodutivo e contraceptivo para prevenir a transmissão do HIV para seus parceiros e prole.OBJECTIVE: To assess incidence and predictors of first pregnancy among women with HIV/AIDS. METHODS: Prospective cohort study was conducted in Rio de Janeiro, southeastern Brazil, between 1996 and 2003. This study comprised 225 women with HIV/AIDS followed up until their first pregnancy or first censored event (hysterectomy, tubal ligation, menopause, 50 years of age, loss to follow-up, death or the end of December 2003). Pregnancy and abortion rates were estimated, and Cox proportional hazards models were used to identify baseline characteristics associated with pregnancy risk. RESULTS: The women were followed up for 565 person/years with a median follow-up of 3 years per women. The mean age was 32 years (SD: 7), and 54.7% were white. There were 60 pregnancies in 39 women, and 18 were terminated (induced abortions), accounting for a rate of 6.9% and 2.1% women/year, respectively. Repeated pregnancies occurred in 33.3% of the women (13/39). Higher pregnancy risk was seen among younger women (HR=3.42; 95%CI: 1.69;6.95) and those living with their partners (HR=1.89; 95%CI: 1.00;3.57). Lower pregnancy risk was associated with higher education level (HR=0.43; 95%CI: 0.19;0.99) and use of antiretroviral therapy (HR=061; 95%CI: 0.31;1.17). CONCLUSIONS: Lower pregnancy rates were found in our cohort than in the general population. Sociodemographic characteristics should be taken into consideration in the management of reproductive health in HIV-positive childbearing age women. Reproductive and family planning counseling must be incorporated into HIV/AIDS programs for women to help preventing HIV transmission to their partners and offspring
- …