50 research outputs found

    Thermal response test for shallow geothermal applications: a probabilistic analysis approach

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    Thermal Response Test (TRT) is an onsite test used to characterize the thermal properties of shallow underground, when used as heat storage volume for shallow geothermal application. It is applied by injecting/extracting heat into geothermal closed-loop circuits inserted into the ground. The most common types of closed loop are the borehole heat exchangers (BHE), horizontal ground collectors (HGC), and energy piles (EP). The interpretation method of TRT data is generally based on a regression technique and on the calculation of thermal properties through different models, specific for each closed loop and test conditions. A typical TRT record is a graph joining a series of experimental temperatures of the thermal carrier fluid. The proposed geostatistical approach considers the temperature as a random function non-stationary in time, with a given trend, therefore the record is considered as a 'realization', one of the possible results; the random nature of the test results is transferred to the fluctuations and a variogram modeling can be applied, which may give many information on the TRT behavior. In this paper, a nested probabilistic approach for TRT output interpretation is proposed, which can be applied for interpreting TRT data, independently of the different methodologies and technologies adopted. In the paper, for the sake of simplicity, the probabilistic approach is applied to the 'infinite line source' (ILS) methodology, which is the most commonly used for BHE. The probabilistic approach, based on variogram modeling of temperature residuals, is useful for identifying with robust accuracy the time boundaries (initial time t 0 and the final time t f) inside which makes temperature regression analysis possible. Moreover, variograms are used into the analysis itself to increase estimation precision of thermal parameter calculation (ground conductivity λ g, ground capacity c g, borehole resistance R b). Finally, the probabilistic approach helps keep under control the effect of any cause of result variability. Typical behaviors of power, flows, and temperatures and of their interaction with the specific closed-loop circuit and geo-hydrological system are deepened by variogram analysis of fluctuations

    Survey of hepatitis B and C infection control: procedures at manicure and pedicure facilities in São Paulo, Brazil

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    AbstractBleeding due to the habit of removing the cuticles of the finger and toes nails, without appropriate sterilization of instruments can be an important factor of contamination by hepatitis B and C viruses. The objectives of this study were to verify the use of standards on biosafety in the routine work of manicurists and/or pedicurists located in São Paulo, Brazil; know the level of information they have about ways of transmission and prevention of hepatitis B and C; evaluate the degree of risk perception for accidental exposure to infectious agents; and to estimate the prevalence of serological markers of hepatitis B and C among them. This was descriptive, cross-sectional study that included a random sample of 100 manicurists and/or pedicurists working in beauty salons. We administered a questionnaire to obtain personal information about the characteristics of the participants, collected blood for hepatitis B and C serology and assessed the working environment. Adherence to the professional standards on biosafety has been inadequate, and we noted that only 5% used disposable gloves, none washed their hands, 93% did not previously cleaned their working material and only 7% used disposable materials. A low level of knowledge about the routes of transmission, prevention, standards of biosafety, and risk perception of the infectious agents in their professional activity was observed. One out of ten interviewed manicurist and/or pedicurist had serological markers of hepatitis B or C, with 8% of hepatitis B and 2% of hepatitis C

    Distribuição dos genótipos do vírus GB-C (HGV) em indivíduos da cidade de São Paulo, Brasil

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    Há na literatura vários estudos filogenéticos e de distribuição de genótipos do chamado "Vírus GB-C" ou da "Hepatite G", mais conhecido pela dupla sigla "GBV-C/HGV". Ocorre que, em sua grande maioria, estas pesquisas foram realizadas com amostras de grupos ligados epidemiologicamente e não com indivíduos representativos da população geral. O presente estudo é uma continuação do primeiro trabalho no Brasil feito com este tipo de amostragem. Trata-se de análise filogenética e distribuição genotípica do GBV-C/HGV a partir de amostras isoladas dentre mais de 1.000 indivíduos da cidade de São Paulo. Para tanto, um fragmento de 728 pares de base da região 5' não-codificadora (5´NCR) do genoma viral, de 24 amostras, foi sequenciado e submetido à analise filogenética. Foram identificados os genótipos 1, 2a e 2b nas respectivas freqüências: 8,3% (2/24), 50% (12/24) e 41,7% (10/24). Concluindo, São Paulo apresenta uma distribuição de genótipos semelhante à publicada para outros estados e regiões do Brasil, endossando a idéia de que os tipos 1 e 2 teriam vindo com os africanos e europeus, respectivamente, e portanto estariam na população do país desde a sua formação.There has been several studies worldwide on phylogenetics and genotype distribution of the GB-virus C / Hepatitis G virus (GBV-C/HGV). However, in their great majority, those investigations were based on some epidemiologically linked group, rather than on a representative sampling of the general population. The present is a continuation of the first study in Brazil with such a population; it addresses the GBV-C/HGV phylogenetics and genotype distribution based on samples identified among more than 1,000 individuals of the city of São Paulo. For this purpose, a 728 bp fragment of the 5´non-coding region (5´NCR) of the viral genome, from 24 isolates, was sequenced and subjected to phylogenetic analysis. Genotypes 1, 2a and 2b were found at 8.3% (2/24), 50% (12/24) and 41.7% (10/24), respectively. In conclusion São Paulo displays a genotype distribution similar to the published data for other States and Regions of Brazil, endorsing the notion that types 1 and 2 would have entered the country with African and European people, respectively, since its earliest formation

    Kikuchi-Fujimoto disease: an unusual association with acute renal failure

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    AbstractKikuchi-Fujimoto disease, also known as histiocytic necrotizing lymphadenitis of unknown etiopathogenesis, is a self-limited disease which frequently appears as feverish lymphadenomegaly, thus creating the need for differential diagnosis with lymphoma, systemic lupus erythematosus (SLE), infectious mononucleosis, cat-scratch disease, and toxoplasmosis with lymphonodal impairment. However, there are cases in which it may evolve with complications such as aseptic meningitis, cerebellar ataxia, and aseptic myocarditis. We are presenting a case of a 24-year-old man who had an initial picture of arthralgia, evening fever and adenomegaly. Kikuchi disease was diagnosed through lymph node biopsy with immunohistochemistry and evolves with severe systemic manifestations, such as pericarditis with cardiac tamponade, pneumonitis, hepatitis, and acute kidney failure - the latter has not been reported in literature yet. There was significant improvement of the clinical picture with prednisone

    Viabilidade da aplicação do teste tuberculínico com o dermo-jet

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    Hipersensibility reaction to the tuberculin test was studied using two types of simultaneous application in young male patients: usual syringe and needle and dermo-jet. The results revealed 61.3% positive reactions with the use of syringe and needle, vs. 40.0% using dermo-jet. These results show that the use of conventional syringe and needle in tuberculin skin tests is still the best current practice.Foram estudadas as reações de hipersensibilidade tuberculínica induzidas por aplicações simultâneas, em adultos jovens, de tuberculina (PPD. RT-23, 2UT), com agulha e seringa e com o dermo-jet. Foram encontrados 61,3% de reatores nas aplicações com agulha e seringa para 40,0% de reatores nas aplicações com o dermo-jet. Os resultados não são considerados favoráveis ao uso do injetor a jato na prática corrente de aplicação do teste tuberculínico

    Nova estimativa da prevalência da infecção pelo vírus "TT" (TTV) em populações de baixo e alto risco de São Paulo, Brasil

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    A prevalência da infecção pelo vírus "TT" (TTV) foi investigada pela técnica da Reação da Polimerase em Cadeia (PCR) em grupos considerados de baixo risco (doadores de sangue e crianças/adolescentes saudáveis) e de alto risco de exposição parenteral (hemofílicos); todos provenientes da cidade de São Paulo. Oligonucleotídeos empregados como primers, homólogos à região não traduzível (UTR) do genoma viral, mostraram-se muito mais universais, revelando frequências muito mais altas em ambos os grupos ( >; ou = 81%) do que os primers anteriormente utilizados, baseados na região genômica traduzível "N22" (doadores de sangue, 5,5%, e hemofílicos, 42,3%). O "PCR-UTR" também revelou um perfil interessante em crianças/adolescentes saudáveis: alta prevalência nos primeiros anos de vida e queda significativa em meninos adolescentes. O "PCR-N22", por sua vez, apresentou alta frequência em hemofílicos que receberam derivados de sangue fresco (58%) relativa àqueles que foram tratados com fatores de coagulação submetidos à inativação viral (9,4%) e doadores de sangue (5,5%).The prevalence of TT virus (TTV) infection was investigated by Polymerase Chain Reaction (PCR) in low- (blood donors and healthy children/adolescents) and high-risk (hemophiliacs) groups from São Paulo, Brazil. Primers based on the untranslated region (UTR) of the viral genome proved to be much more ubiquitous, leading to much higher frequencies for both groups ( >; or = 81%) than the earlier N22-PCR directed to the open reading frame 1 (blood donors, 5.5%, and hemophiliacs, 42.3%). The UTR-PCR also revealed an interesting profile for healthy children/adolescents: very high prevalence at the early years and significant decrease in male teenagers. The N22-PCR, in turn, demonstrated higher frequency in hemophiliacs treated with fresh blood products (58%), than in those treated with virus-inactivated clotting factors (9.4%) and blood donors (5.5%)
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