13 research outputs found

    Analysis of negative polarity parameters of the MAG-VP process on angular distortions

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    O objetivo deste trabalho é entender a influência da polaridade negativa no processo de soldagem MAG Polaridade Variável, em particular para aplicações de revestimento. Para isso foram escolhidos individualmente os parâmetros da polaridade negativa e analisados em relação à distorção angular da junta soldada, utilizando aço ao carbono como metal base e aço inoxidável como metal de adição. Foi aplicada a metodologia de superfície de resposta e o projeto de experimentos Box-Behnken no planejamento e execução do experimento, variando três fatores: tempo de corrente de base positiva, tempo de corrente negativa e corrente negativa, em três níveis cada um. Os três parâmetros principais avaliados apresentaram efeito significativo sobre a distorção angular. O menor valor de distorção angular foi obtido para o tempo da corrente de base positiva (15 ms), tempo de corrente negativa (15 ms) e intensidade de corrente negativa (-50 A). Todos eles apresentaram efeitos significativos no resultado final, responsável pelo menor valor de distorção angular, aproximadamente 0,02748 rad. Posteriormente, foi realizada a validação do modelo matemático para o alvo de menor valor da distorção angular estimado, o erro (%) entre os resultados da distorção angular estimada mediante a equação de regressão e o experimento foi de 3,65%.It is intended to understand the influence of negative polarity on MAG variable polarity manufacturing process, in particular for coating applications, for that the negative polarity parameters were chosen individually and evaluated according to the angular distortion of the welded joint using carbon as base metal and stainless steel as filler metal. The response surface methodology and the Box-Behnken design of experiments were applied in the design and execution of the experiment varying three factors: base current time, negative current time and negative current, in three levels each. The three main parameters evaluated had a significant effect on angular distortion. The lowest angular distortion value was obtained with a positive base current time of 15 ms, negative current time of 15 ms and negative current intensity of -50 A. All of which had significant effects on the final result, responsible for the lowest angle of distortion of approximately 0,02748 rad. Subsequently, a validation of the mathematical model was performed with the lowest estimated angular distortion value. The error (%) between the estimated angular distortion through the regression equation and the experiment was 3.65%

    Seroepidemiology Survey of Bovine Alphaherpesvirus 1 (BoHV-1) in Unvaccinated Beef Bubalines (Bubalus bubalis) from Southern Brazil

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    Background: The bovine alphaherpesvirus type 1 (BoHV-1) belonging to the order Herpesvirales, family Herpesviridae, subfamily Alphaherpesvirinae and genus Varicellovirus.Bovine alphaherpesvirus 1 (BoHV-1) infections have a great importance due to the high rates of dissemination in cattles worldwide. Although, the BoHV-1 was largely related in cattle, buffaloes were also classified as host for the virus. However, studies that determine seroepidemiological data in this species are scarce and necessary. The aim of the present study was to determine the presence of antibodies against BoHV-1 in healthy beef buffaloes using the virus neutralization (VN) technique.Cases: This work portrays an epidemiological survey, based on a sectional study characterized by blood samples collected from 54 Murrah buffalo, aged 6 to 24 months, from the municipalities of Guaraqueçaba, Ponta Grossa, Antonina and Doutor Ulysses, located in Paraná state, being 20, 14, 10 and 10 samples from each location, respectively. Thirty-seven percent (20/54) of the samples were collected at slaughterhouse with registration at the Federal Inspection Service (SIF) of the Ministry of Agriculture, Livestock and Food Supply (MAPA), and 63% (34/54) at the buffalo's farms. The serum samples were collected in sterile tubes without anticoagulant in stored isothermal boxes, with serum separation and stored at -20ºC. The samples were sent to the Animal Virology Laboratory of Universidade Estadual de Londrina, UEL for serological analysis. Serological diagnosis using the virus neutralization (VN) technique was performed according the OIE manual of diagnostic tests and vaccines for terrestrial animals, using the BoHV-1 Los Angeles strain. Forth-five of the 54 samples (83.3%) evaluated generated titers of antibodies against BoHV-1 present in all evaluated herds, and the samples collected in herd from Antonina city were 100% positive, following by 80% in Guaraqueçaba and Doutor Ulysses city, and 78.6% in Ponta Grossa city. In relationship to the titration of anti-bovine herpesvirus 1 antibodies (BoHV-1), it was found that 23/45 (51.12%) of the samples had titers ≤ 16, 13/45 (28.88 %) with indexes between 32-64, and 9/45 (20%) with levels above 128.Discussion: The confirmation of the presence of antibodies against BoHV-1 in the buffalo samples tested in the present study proves the circulation of the agent in the studied species, with a homogeneous distribution of bovine alphaherpesvirus 1 in all the evaluated herds. There was high variability in antibody titers against BoHV-1 from all herds, and the occurrence of a high number of buffaloes reactive to BoHV-1 and with high antibody titers suggests a course of active or reactive infections in these animals. In only one of the herds, the age of the animals studied varied between 6 to 8 months. The fact that these animals are lactating raises the possibility of anti-BoHV-1 antibodies being acquired by breastfeeding. The results obtained allow to conclude, considering the fact that the animals are not vaccinated against BoHV-1, the presence of circulating antibodies is from a natural infection, and the positivity in all farms tested denotes the endemicity of the BoHV-1 infection in herds. To the best knowledge of the authors, this is the first study on the detection and measurement of antibodies against BoHV-1 in healthy and unvaccinated buffaloes in the state of Paraná, southern Brazil, showing a high frequency of seroreagent animals.

    Analyses of 32 Loci Clarify Phylogenetic Relationships among Trypanosoma cruzi Lineages and Support a Single Hybridization prior to Human Contact

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    Trypanosoma cruzi is the protozoan parasite that causes Chagas disease, a major health problem in Latin America. The genetic diversity of this parasite has been traditionally divided in two major groups: T. cruzi I and II, which can be further divided in six major genetic subdivisions (subgroups TcI-TcVI). T. cruzi I and II seem to differ in important biological characteristics, and are thought to represent a natural division relevant for epidemiological studies and development of prophylaxis. Having a correct reconstruction of the evolutionary history of T. cruzi is essential for understanding the potential connection between the genetic and phenotypic variability of T. cruzi with the different manifestations of Chagas disease. Here we present results from a comprehensive phylogenetic analysis of T. cruzi using more than 26 Kb of aligned sequence data. We show strong evidence that T. cruzi II (TcII-VI) is not a natural evolutionary group but a paraphyletic lineage and that all major lineages of T. cruzi evolved recently (<3 million years ago [mya]). Furthermore, the sequence data is consistent with one major hybridization event having occurred in this species recently (< 1 mya) but well before T. cruzi entered in contact with humans in South America

    O desafio de buscar o equilíbrio entre flexibilidade e qualidade

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    Orientador : Gianfranco MuncinelliTrabalho de Conclusão de Curso (especialização) - Universidade Federal do Paraná, Setor de Ciências Sociais Aplicadas, Curso de Especialização MBA em Gestão EstratégicaInclui referência

    A institucionalização da sociologia no ensino superior paranaense

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    Procuramos apresentar os resultados preliminares da pesquisa sobre a História da Sociologia no Paraná, com ênfase particularmente no processo de sua institucionalização enquanto disciplina acadêmico-científica nas Instituições de Ensino Superior (IES). O objetivo principal é destacar a constante descontinuidade na trajetória de consolidação dos cursos de Ciências Sociais, bem como a presença tímida da Sociologia neste contexto de relações acadêmicas

    Seroepidemiology Survey of Bovine Alphaherpesvirus 1 (BoHV-1) in Unvaccinated Beef Bubalines (Bubalus bubalis) from Southern Brazil

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    Background: The bovine alphaherpesvirus type 1 (BoHV-1) belonging to the order Herpesvirales, family Herpesviridae, subfamily Alphaherpesvirinae and genus Varicellovirus.Bovine alphaherpesvirus 1 (BoHV-1) infections have a great importance due to the high rates of dissemination in cattles worldwide. Although, the BoHV-1 was largely related in cattle, buffaloes were also classified as host for the virus. However, studies that determine seroepidemiological data in this species are scarce and necessary. The aim of the present study was to determine the presence of antibodies against BoHV-1 in healthy beef buffaloes using the virus neutralization (VN) technique.Cases: This work portrays an epidemiological survey, based on a sectional study characterized by blood samples collected from 54 Murrah buffalo, aged 6 to 24 months, from the municipalities of Guaraqueçaba, Ponta Grossa, Antonina and Doutor Ulysses, located in Paraná state, being 20, 14, 10 and 10 samples from each location, respectively. Thirty-seven percent (20/54) of the samples were collected at slaughterhouse with registration at the Federal Inspection Service (SIF) of the Ministry of Agriculture, Livestock and Food Supply (MAPA), and 63% (34/54) at the buffalo's farms. The serum samples were collected in sterile tubes without anticoagulant in stored isothermal boxes, with serum separation and stored at -20ºC. The samples were sent to the Animal Virology Laboratory of Universidade Estadual de Londrina, UEL for serological analysis. Serological diagnosis using the virus neutralization (VN) technique was performed according the OIE manual of diagnostic tests and vaccines for terrestrial animals, using the BoHV-1 Los Angeles strain. Forth-five of the 54 samples (83.3%) evaluated generated titers of antibodies against BoHV-1 present in all evaluated herds, and the samples collected in herd from Antonina city were 100% positive, following by 80% in Guaraqueçaba and Doutor Ulysses city, and 78.6% in Ponta Grossa city. In relationship to the titration of anti-bovine herpesvirus 1 antibodies (BoHV-1), it was found that 23/45 (51.12%) of the samples had titers ≤ 16, 13/45 (28.88 %) with indexes between 32-64, and 9/45 (20%) with levels above 128.Discussion: The confirmation of the presence of antibodies against BoHV-1 in the buffalo samples tested in the present study proves the circulation of the agent in the studied species, with a homogeneous distribution of bovine alphaherpesvirus 1 in all the evaluated herds. There was high variability in antibody titers against BoHV-1 from all herds, and the occurrence of a high number of buffaloes reactive to BoHV-1 and with high antibody titers suggests a course of active or reactive infections in these animals. In only one of the herds, the age of the animals studied varied between 6 to 8 months. The fact that these animals are lactating raises the possibility of anti-BoHV-1 antibodies being acquired by breastfeeding. The results obtained allow to conclude, considering the fact that the animals are not vaccinated against BoHV-1, the presence of circulating antibodies is from a natural infection, and the positivity in all farms tested denotes the endemicity of the BoHV-1 infection in herds. To the best knowledge of the authors, this is the first study on the detection and measurement of antibodies against BoHV-1 in healthy and unvaccinated buffaloes in the state of Paraná, southern Brazil, showing a high frequency of seroreagent animals.

    Concomitant bovine viral diarrhea, mycotoxicosis, and seneciosis in cattle from northern Paraná, Brazil

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    O objetivo desse estudo foi avaliar a causa de mortalidade observada em um rebanho bovino constituído por vacas da raça Nelore criadas no norte do Estado do Paraná, região sul do Brasil, no qual 9,5% (23/242) das vacas morreram após manifestação clínica de andar cambaleante, febre, diarreia transitória com sangue, dispneia e decúbito lateral. O rebanho era mantido em pastagens degradadas e ingeriram silagem de milho mofada e broto de Senecio brasiliensis. Amostras de soro (n=17) foram coletadas para a detecção de anticorpos neutralizantes para o vírus da diarreia viral bovina (BVDV) e herpesvírus bovino 1 (BoHV-1). Três vacas foram necropsiadas e os fragmentos de tecidos foram avaliados por RT-PCR e PCR para a identificação de BVDV e BoHV-1, respectivamente. Os achados macroscópicos incluíram aumento da consistência hepática, sangramento intestinal e hemorragia pulmonar. A histopatologia revelou fibrose hepática, enterite hemorrágica, necrose tubular renal e vasculite generalizada. Todas as amostras de soro apresentaram anticorpos neutralizantes para o BoHV-1 e seis amostras foram positivas para o BVDV. A RT-PCR amplificou produtos da região não-traduzida do genoma do BVDV a partir de tecidos de ambos os animais. Análises filogenéticas dos produtos amplificados demonstraram que as sequências agruparam com o BVDV subgenotipo 1d. Todas as amostras analisadas por PCR para a identificação do DNA do BoHV-1 foram negativas. Análises toxicológicas nas amostras de silagem milho mofada apresentaram altas concentrações de ocratoxina (75,94 ?g/kg). Esses resultados confirmam que as ações combinadas da infecção com o BVDV-1d, a micotoxicose e a intoxicação por Senecio contribuíram com a mortalidade de vacas no rebanho avaliado.This study investigated the causes of mortality in cattle from northern Paraná, southern Brazil, during which 9.5% (23/242) of Nellore cows died after clinical manifestations of uncoordinated gait, fever, transient bloody diarrhea, dyspnea, and lateral decumbency. All cattle were maintained on poor pastures, and ingested moldy silage and sprouts of Senecio brasiliensis. Serum samples (n=17) were collected for virus neutralizing (VN) antibodies assays against bovine viral diarrhea virus (BVDV) and bovine herpesvirus 1 (BoHV-1). Three cows were necropsied; fragment of tissue samples collected during necropsy from two cows were used in polymerase chain reaction (PCR) and reverse transcription- PCR assays to identify BoHV-1 and BVDV; blood samples (n=6) were obtained for hematological and biochemical analyses. Significant gross findings of all cows included increased liver consistency, intestinal bleeding, and pulmonary hemorrhage. Histopathology revealed hepatic fibrosis, hemorrhagic enteritis, renal tubular necrosis, pulmonary hemorrhage, and widespread vasculitis. All serum samples contained VN antibodies against BoHV-1, but only four of these reacted positively to BVDV. The RTPCR assays amplified specific amplicons of the untranslated region of BVDV from tissues samples of both animals; direct sequencing and sequence analyses demonstrated that these sequences clustered within the BVDV subgenotype 1d; all PCRs were negative for BoHV-1. Toxicological analyses of the moldy silage demonstrated elevated concentrations of ochratoxin (75.94 ?g/kg). Laboratory evaluations revealed renal and hepatic dysfunctions. These findings confirmed the combined actions of BVDV-1d infection and toxicosis by mycotoxin and S. brasiliensis in cattle mortality at this farm
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