153 research outputs found

    A Real Options Model with Games Applied to the Rio de Janeiro Residential Real Estate Market

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    Purpose – To determine the optimal investment strategy in Nash equilibrium for the residential real estate market of Rio de Janeiro, considering the uncertainty in the demand for real estate and the number of active competitors in the market. Design/methodology/approach – A Real Options Game model was developed. The parameters of the model were estimated with econometric tools using data from the Rio de Janeiro real estate market. Findings – The quantitative results obtained are intuitive in the sense that the larger the number of competitors, the lower the level of demand required for investment in new units, whereas the greater the volatility of demand, the greater the demand threshold for the investment to be optimal. Originality/value – This study modified the methodology of Grenadier (2002), providing a more adequate and robust specification of the uncertainty for the demand function, thus allowing more intuitive economic interpretations

    Cardiac troponin I levels in patients with refractory temporal lobe epilepsy after cortico-amygdalo-hippocampectomy

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    PURPOSE: Sudden unexpected death in epilepsy (SUDEP) is the main cause of death in patients with epilepsy. Morphologic and functional changes in the heart are related to SUDEP. The aim of our study was to verify the concentration of troponin I, an important marker of myocardium damage, in patients with temporal lobe epilepsy who were submitted to surgical resection and were not seizure-free after the procedure. METHODS: Eleven non-consecutive patients participated in the study and all of them presented poor seizure control after surgical procedure. Troponin I levels higher then 1 ng/ml indicate myocardium damage. The detection level of the kit used in our study was 0,15 ng/ml. RESULTS: Only three patients showed detectable troponin I levels. The troponin I levels found in our study is not related with sex, age or side of the lesion. CONCLUSIONS: In spite of we did not find positive results in our study, an active role of the heart in SUDEP cannot be discarded, since some injuries, even so not being capable to modify troponin I levels, can be enough to generate arrhythmogenic foci.OBJETIVOS: A morte súbita em epilepsia (SUDEP) é a principal causa de morte entre os pacientes com epilepsia. Alterações morfológicas e funcionais do coração estão relacionadas com a SUDEP. Nesse sentido, o objetivo deste estudo foi avaliar a concentração de troponina I, um importante marcador de lesão do miocárdio, em pacientes com epilepsia do lobo temporal de difícil controle e que foram submetidos à ressecção cirúrgica e que não obtiveram sucesso com esta abordagem terapêutica. METODOLOGIA: Onze pacientes participaram do estudo e todos continuaram a apresentar crises após o tratamento cirúrgico. Os valores de troponina I indicativos de lesão seriam aqueles maiores de 1 ng/ml e o valor mínimo detectável pelo kit utilizado em nosso estudo foi de 0,15 ng/ml. RESULTADOS: Apenas três pacientes apresentaram níveis de troponina I detectáveis. Em relação aos níveis detectáveis de troponina I, não encontramos nenhuma relação com sexo, idade e lateralidade da lesão. CONCLUSÕES: APESAr de não termos encontrado resultados positivos em nosso estudo, o papel do coração na SUDEP não pode ser descartado, já que algumas lesões, embora não sendo capazes de alterar os níveis séricos de troponina I, podem ser suficientes na gênese de focos arritmogênicos.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade de Mogi das Cruzes Núcleo de Pesquisas TecnológicasHospital Brigadeiro Departamento de Neurologia e NeurocirurgiaCentro Universitário São CamiloHospital Israelita Albert EinsteinUniversidade Federal de São João del-Rei Departamento de Engenharia BiomédicaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de FisiologiaUNIFESP, EPM, Depto. de FisiologiaSciEL

    The Heart and COVID-19: What Cardiologists Need to Know

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    In face of the pandemic of the novel coronavirus disease 2019 (COVID-19), the management of patients with cardiovascular risk factors and/or disease is challenging. The cardiovascular complications evidenced in patients with COVID-19 derive from several mechanisms, ranging from direct viral injury to complications secondary to the inflammatory and thrombotic responses to the infection. The proper care of patients with COVID-19 requires special attention to the cardiovascular system aimed at better outcomes

    Association of Chlamydia trachomatis, C. pneumoniae, and IL-6 and IL-8 Gene Alterations With Heart Diseases

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    Atherosclerosis is a progressive disease characterized by chronic inflammation of the arterial walls, associated with genetic and infectious factors. The present study investigated the involvement of Chlamydia trachomatis and Chlamydia pneumoniae infections and immunological markers (C-reactive protein, CRP, TNF-α, IL-6, IL-8, and IL-10) in the process of atherosclerosis. The evaluation included 159 patients for surgical revascularization (CAD) and 71 patients for surgical heart valve disease (HVD) at three hospitals in Belém, Brazil. The control group (CG) comprised 300 healthy individuals. Blood samples collected before surgery were used for antibodies detection (enzyme immunoassay), CRP (immunoturbidimetry) and IL-6 levels (enzyme immunoassay). Tissue fragments (atheroma plaque, heart valve and ascending aorta) were collected during surgery and subjected to qPCR for detection of bacterial DNA. Promoter region polymorphisms of each marker and relative quantification of TNF-α, IL-8, and IL-10 gene expression were performed. Demography and social information were similar to the general population involved with both diseases. Antibody prevalence to C. trachomatis was 30.6, 20.3, and 36.7% (in the CAD, HVD, and CG, respectively) and to C. pneumoniae was 83.6, 84.5, and 80.3% (in the CAD, HVD, and CG, respectively). C. trachomatis cryptic plasmid DNA was detected in 7.4% of the samples. Frequency of IL6−174G>C polymorphism was higher in CAD and HVD than in CG regardless of previous exposure to Chlamydia. Previous C. trachomatis infection showed involvement in HVD and CAD. Significant association between disease and previous C. pneumoniae infection was found only among HVD. GG genotype of IL6−174G>C is apparently a risk factor for heart disease, whereas AT genotype of IL8−251A>T was mainly involved in valvulopathies, including patients with prior exposure to C. pneumoniae

    Extraction of subjective properties in image processing

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    Most of the present digital images processing methods are related with objective characterization of external properties as shape, form or colour. This information concerns objective characteristics of different bodies and is applied to extract details to perform several different tasks. But in some occasions, some other type of information is needed. This is the case when the image processing system is going to be applied to some operation related with living bodies. In this case, some other type of object information may be useful. As a matter of fact, it may give additional knowledge about its subjective properties. Some of these properties are object symmetry, parallelism between lines and the feeling of size. These types of properties concerns more to internal sensations of living beings when they are related with their environment than to the objective information obtained by artificial systems. This paper presents an elemental system able to detect some of the above-mentioned parameters. A first mathematical model to analyze these situations is reported. This theoretical model will give the possibility to implement a simple working system. The basis of this system is the use of optical logic cells, previously employed in optical computing

    O Coração e a COVID-19: O que o Cardiologista Precisa Saber

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    Frente à pandemia da doença causada pelo novo coronavírus (COVID-19), o manejo do paciente com fator de risco e/ou doença cardiovascular é desafiador nos dias de hoje. As complicações cardiovasculares evidenciadas nos pacientes com COVID-19 resultam de vários mecanismos, que vão desde lesão direta pelo vírus até complicações secundárias à resposta inflamatória e trombótica desencadeada pela infecção. O cuidado adequado do paciente com COVID-19 exige atenção ao sistema cardiovascular em busca de melhores desfechos
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