66 resultados para HEV


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Electric vehicles (EVs) and hybrid EVs are the way forward for green transportation and for establishing low-carbon economy. This paper presents a split converter-fed four-phase switched reluctance motor (SRM) drive to realize flexible integrated charging functions (dc and ac sources). The machine is featured with a central-tapped winding node, eight stator slots, and six rotor poles (8/6). In the driving mode, the developed topology has the same characteristics as the traditional asymmetric bridge topology but better fault tolerance. The proposed system supports battery energy balance and on-board dc and ac charging. When connecting with an ac power grid, the proposed topology has a merit of the multilevel converter; the charging current control can be achieved by the improved hysteresis control. The energy flow between the two batteries is balanced by the hysteresis control based on their state-of-charge conditions. Simulation results in MATLAB/Simulink and experiments on a 150-W prototype SRM validate the effectiveness of the proposed technologies, which may provide a solution to EV charging issues associated with significant infrastructure requirements.

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Hepatitis E virus (HEV) is a fecal-orally transmitted member of the genus Hepevirus that causes acute hepatitis in humans and is widely distributed throughout the world. Pigs have been reported as the main source of genotypes 3 and 4 infection to humans in non-endemic areas. To investigate HEV infection in pigs from different regions of Para state (Eastern Brazilian Amazon), we performed serological and molecular analyses of serum, fecal and liver samples from 151 adult pigs slaughtered between April and October 2010 in slaughterhouses in the metropolitan region of Belem, Para. Among the animals tested, 8.6% (13/151) were positive for anti-HEV IgG but not for anti-HEV IgM. HEV RNA was detected in 4.8% (22/453) of the samples analyzed and 9.9% (15/151) of the animals had at least one positive sample. Phylogenetic analysis showed that all sequences belonged to genotype 3 that were related to human isolates from other non-endemic regions, suggesting that the isolates had zoonotic potential. Subtypes 3c and 3f were simultaneously detected in some pigs, suggesting co-infection by more than one strain and/or the presence of a recombinant virus. These results constitute the first molecular and serologic evidence of swine HEV circulation in the Eastern Brazilian Amazon. (C) 2012 Elsevier Ltd. All rights reserved.

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Hev b 13 is an allergenic esterase obtained from the rubber tree Hevea brasiliensis, which has been shown recently to induce human mononuclear cells to release interleukin (IL)-10 in vitro. This immunoregulatory cytokine appears to play an important role in preventing inflammation and mucosal damage in animal models of colitis and in Crohn's disease patients. The aim of this study was to evaluate the therapeutic effect of Hev b 13 in mice with 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced colitis. Two hours following colonic instillation of the haptenizing agent, and daily thereafter for 5 days, Hev b 13 was administered by oral gavage. In mice treated with daily doses of either 0.5 mg/kg or 5.0 mg/kg of Hev b 13, the clinical signs of diarrhoea, rectal prolapse and body weight loss and also histological damage of the distal colon, were reduced significantly, in comparison with water-treated diseased mice. These findings suggest a potent anti-inflammatory activity of Hev b 13; this activity is speculated to be related to its interaction with cells from the immune system.

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Hev b 13 is an allergenic esterase obtained from the rubber tree Hevea brasiliensis, which has been shown recently to induce human monocytes to release interleukin (IL)-10 in vitro, and to exert a potent anti-inflammatory effect in vivo. Moreover, Hev b 13 has been shown to reduce clinical signs of inflammation and also histological damage to the distal colon of mice with 2,4,6-trinitrobenze sulphonic acid (TNBS)-induced colitis after its oral administration. The aim of this study was to investigate the effect of Hev b 13 on human mononuclear cells, as well as its therapeutic use in the methylated bovine serum albumin (mBSA) model of antigen-induced arthritis. Five days before the intra-articular challenge, and daily thereafter for 8 days, Hev b 13 was administered by oral gavage. In mice treated with a dose of 0.5 mg/kg of Hev b 13, the severity of oedema, leucocyte infiltration, pannus formation and cartilage erosion were reduced significantly. These findings underscore the anti-inflammatory activity suggested previously for Hev b 13, an activity speculated to be related to its interaction with monocytes/macrophages and the consequent stimulation of IL-10 release and reduction of tumour necrosis factor (TNF) release. The study also opens a wide range of possible applications in the field of immune-mediated inflammatory diseases.

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L'epatite E è una malattia umana con caratteristiche di epatite acuta, causata da un ssRNA virus (HEV). Nel 1997, HEV è stato identificato per la prima volta nei suini (SwHEV). In seguito, diverse evidenze, tra cui la vicinanza genetica tra ceppi umani e suini, suggerirono la trasmissione zoonotica del virus. Nella presente tesi, l’identificazione di SwHEV è stata condotta mediante ricerca di porzioni di genoma virale attraverso RT-PCR. Dal 2011 al 2013, sono stati analizzati 343 campioni fecali (da 19 allevamenti) e 70 bili (da 2 macelli) prelevati da altrettanti suini, in diverse Regioni italiane. E’ stato inoltre condotto uno studio retrospettivo su 78 feci (da 3 allevamenti) raccolte nel 2000. Il virus è stato identificato nel 24,5% e 19,2% delle feci raccolte rispettivamente nel 2011-2013 e nel 2000. Nessuna bile è risultata positiva. Mediante sequenziamento del genoma intero di uno dei virus identificati, è stata condotta l’analisi filogenetica per valutarne il grado di correlazione con alti ceppi suini e umani. La presenza di HEV è stata valutata lungo la filiera di produzione suina, dal macello al punto vendita. Trentaquattro campioni di feci, fegato e muscolo sono stati raccolti in un macello da altrettanti suini sani (età:6-7 mesi). Quattordici feci e 2 fegati, sono risultati positivi per HEV. Sono state prelevate 129 salsicce sia allo stabilimento di trasformazione sia alla vendita, ma nessuna è risultata positiva. La presenza di HEV è stata valutata anche nelle salsicce di fegato, fresche e secche, acquistate presso una macelleria. Il genoma virale è stato rilevato nel 22,2% delle salsicce fresche e nel 4,3 % di quelle secche ma la vitalità del virus non è stata dimostrata. In conclusione, lo studio condotto ha confermato l’ampia circolazione di HEV nei suini e la possibile contaminazione dei prodotti carnei derivati, confermando la necessità di una continua sorveglianza.

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The vascular-stromal compartment of lymph nodes is important for lymph node function, and high endothelial venules (HEVs) play a critical role in controlling the entry of recirculating lymphocytes. In autoimmune and autoinflammatory diseases, lymph node swelling is often accompanied by apparent HEV expansion and, potentially, targeting HEV expansion could be used therapeutically to limit autoimmunity. In previous studies using mostly flow cytometry analysis, we defined three differentially regulated phases of lymph node vascular-stromal growth: initiation, expansion, and the re-establishment of vascular quiescence and stabilization. In this study, we use optical projection tomography to better understand the morphologic aspects of HEV growth upon immunization with ovalbumin/CFA (OVA/CFA). We find HEV elongation as well as modest arborization during the initiation phase, increased arborization during the expansion phase, and, finally, vessel narrowing during the re-establishment of vascular quiescence and stabilization. We also examine acutely enlarged autoinflammatory lymph nodes induced by regulatory T cell depletion and show that HEVs are expanded and morphologically similar to the expanded HEVs in OVA/CFA-stimulated lymph nodes. These results reinforce the idea of differentially regulated, distinct phases of vascular-stromal growth after immunization and suggest that insights gained from studying immunization-induced lymph node vascular growth may help to understand how the lymph node vascular-stromal compartment could be therapeutically targeted in autoimmune and autoinflammatory diseases.

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A infecção pelo HEV é reconhecida como um considerável problema de saúde pública em diversas regiões do mundo. Embora caracterizada como uma infecção benigna com um curso evolutivo autolimitado, recentes estudos têm mostrado sua evolução para cronicidade em indivíduos imunocomprometidos. Além disso, tem sido verificado que nesses indivíduos a infecção crônica pelo HEV pode evoluir para fibrose hepática progressiva, culminando com o desenvolvimento de cirrose. Não existem dados acerca da prevalência da infecção pelo HEV em pacientes infectados pelo HIV no Brasil, onde a circulação deste vírus tem sido demonstrada em diversos grupos de indivíduos imunocompetentes e, até mesmo, em alguns animais provenientes de diferentes regiões do país. Com base nisso, este trabalho teve como objetivo estimar a prevalência de marcadores sorológicos e moleculares da infecção pelo HEV, bem como a padronização de uma PCR em tempo real para a detecção e quantificação da carga viral do HEV na população de soropositivos da cidade de São Paulo. Foram incluídos neste estudo soro e plasma de pacientes infectados pelo HIV (n=354), que foram divididos em grupos de acordo com a presença ou ausência de coinfecção pelos vírus das hepatites B (HBV) e C (HCV). Essas amostras foram coletadas entre 2007 e 2013. Anticorpos anti-HEV IgM e IgG foram pesquisados pela técnica de ELISA (RecomWell HEV IgM/ IgG - MIKROGEN®), e, em alguns casos, confirmados por Immunoblotting (RecomLine HEV IgM/ IgG - MIKROGEN®). Todas as amostras foram submetidas à pesquisa de HEV RNA através da PCR em tempo real padronizada. Cerca de 72% dos indivíduos avaliados pertenciam ao sexo masculino. A média de idade entre a população analisada foi de 48,4 anos. Os anticorpos anti-HEV IgM e IgG foram encontrados em 1,4% e 10,7% dos indivíduos dessa população, respectivamente. Apenas dois pacientes apresentaram positividade simultânea para anti-HEV IgM e IgG. Não houve diferença estatisticamente relevante quanto à presença de marcadores sorológicos nos grupos de estudo. Além disso, foi detectado o HEV RNA em 10,7% das amostras analisadas, entre as quais, seis apresentaram simultaneamente algum marcador sorológico (5 anti-HEV IgG e 1 IgM). A presença deste marcador foi predominante no grupo de pacientes com coinfecção pelo HCV. Através deste trabalho pôde-se constatar, portanto, que o HEV é circulante entre a população de infectados pelo HIV em São Paulo, e que o seguimento desses pacientes se faz necessário dado a possibilidade de progressão para infecção crônica e cirrose

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Electric vehicles (EVs) and hybrid EVs are the way forward for green transportation and for establishing low-carbon economy. This paper presents a split converter-fed four-phase switched reluctance motor (SRM) drive to realize flexible integrated charging functions (dc and ac sources). The machine is featured with a central-tapped winding node, eight stator slots, and six rotor poles (8/6). In the driving mode, the developed topology has the same characteristics as the traditional asymmetric bridge topology but better fault tolerance. The proposed system supports battery energy balance and on-board dc and ac charging. When connecting with an ac power grid, the proposed topology has a merit of the multilevel converter; the charging current control can be achieved by the improved hysteresis control. The energy flow between the two batteries is balanced by the hysteresis control based on their state-of-charge conditions. Simulation results in MATLAB/Simulink and experiments on a 150-W prototype SRM validate the effectiveness of the proposed technologies, which may provide a solution to EV charging issues associated with significant infrastructure requirements.

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The University of Queensland UltraCommuter concept is an ultra- light, low-drag, hybrid-electric sports coupe designed to minimize energy consumption and environmental impact while enhancing the performance, styling, features and convenience that motorists enjoy. This paper presents a detailed simulation study of the vehicle's performance and fuel economy using ADVISOR, including a detailed description of the component models and parameters assumed. Results from the study include predictions of a 0-100 kph acceleration time of ≺9s, and top speed of 170 kph, an electrical energy consumption of ≺67 Wh/km in ZEV mode and a petrol-equivalent fuel consumption of ≺2.5 L/100 km in charge-sustaining HEV mode. Overall, the results of the ADVISOR modelling confirm the UltraCommuter's potential to achieve high performance with high efficiency, and the authors look forward to a confirmation of these estimates following completion of the vehicle.

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Fifty-nine persons with industrial handling of low levels of acrylonitrile (AN) were studied. As part of a medical surveillance programme an extended haemoglobin adduct monitoring [N-(cyanoethyl)valine, CEV; N- (methyl)valine, MV; N-(hydroxyethyl)valine, HEV] was performed. Moreover, the genetic states of the polymorphic glutathione transferases GSTM1 and GSTT1 were assayed by polymerase chain reaction (PCR). Repetitive analyses of CEV and MV in subsequent years resulted in comparable values (means, 59.8 and 70.3 μg CEV/1 blood; 6.7 and 6.7 μg MV/1 blood). Hence, the industrial AN exposures were well below current official standards. Monitoring the haemoglobin adduct CEV appears as a suitable means of biomonitoring and medical surveillance under such exposure conditions. There was also no apparent correlation between the CEV and HEV or CEV and MV adduct levels. The MV and HEV values observed represented background levels, which apparently are not related to any occupational chemical exposure. There was no consistent effect of the genetic GSTM1 or GSTT1 state on CEV adduct levels induced by acrylonitrile exposure. Therefore, neither GSTM1 nor GSTT1 appears as a major AN metabolizing isoenzyme in humans. The low and physiological background levels of MV were also not influenced by the genetic GSTM1 state, but the MV adduct levels tended to be higher in GSTT1- individuals compared to GSTT1 + persons. With respect to the background levels of HEV adducts observed, there was no major influence of the GSTM1 state, but GST- individuals displayed adduct levels that were about 1/3 higher than those of GSTT1+ individuals. The coincidence with known differences in rates of background sister chromatid exchange between GSTT1- and GSTT1 + persons suggests that the lower ethylene oxide (EO) detoxification rate in GSTT1- persons, indicated by elevated blood protein hydroxyethyl adduct levels, leads to an increased genotoxic effect of the physiological EO background.

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A veterinarian became infected with Hendra virus (HeV) after managing a terminally ill horse and performing a limited autopsy with inadequate precautions. Although she was initially only mildly ill, serological tests suggested latent HeV infection. Nevertheless, she remains well 2 years after her initial illness. Recently emerged zoonotic viruses, such as HeV, necessitate appropriate working procedures and personal protective equipment in veterinary practice.

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The emergence of Nipah virus (NiV) in Malaysia in 1999 resulted in 265 known human infections (105 fatal), widespread infection in pigs (with >1 million culled to control the outbreak), and the collapse of the Malaysian pig export market. As with the closely related Hendra virus (HeV) that emerged in Australia in 1994 and caused fatal disease in horses and humans, bats of the genus Pteropus (commonly known as flying foxes) were identified as the major reservoir of Nipah virus in Malaysia. This report describes a serologic survey of Pteropus vampyrus in neighboring Indonesia.

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For the problem of speaker adaptation in speech recognition, the performance depends on the availability of adaptation data. In this paper, we have compared several existing speaker adaptation methods, viz. maximum likelihood linear regression (MLLR), eigenvoice (EV), eigenspace-based MLLR (EMLLR), segmental eigenvoice (SEV) and hierarchical eigenvoice (HEV) based methods. We also develop a new method by modifying the existing HEV method for achieving further performance improvement in a limited available data scenario. In the sense of availability of adaptation data, the new modified HEV (MHEV) method is shown to perform better than all the existing methods throughout the range of operation except the case of MLLR at the availability of more adaptation data.

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Nipah virus (NiV) (Genus Henipavirus) is a recently emerged zoonotic virus that causes severe disease in humans and has been found in bats of the genus Pteropus. Whilst NiV has not been detected in Australia, evidence for NiV-infection has been found in pteropid bats in some of Australia's closest neighbours. The aim of this study was to determine the occurrence of henipaviruses in fruit bat (Family Pteropodidae) populations to the north of Australia. In particular we tested the hypothesis that Nipah virus is restricted to west of Wallace's Line. Fruit bats from Australia, Papua New Guinea, East Timor and Indonesia were tested for the presence of antibodies to Hendra virus (HeV) and Nipah virus, and tested for the presence of HeV, NiV or henipavirus RNA by PCR. Evidence was found for the presence of Nipah virus in both Pteropus vampyrus and Rousettus amplexicaudatus populations from East Timor. Serology and PCR also suggested the presence of a henipavirus that was neither HeV nor NiV in Pteropus alecto and Acerodon celebensis. The results demonstrate the presence of NiV in the fruit bat populations on the eastern side of Wallace's Line and within 500 km of Australia. They indicate the presence of non-NiV, non-HeV henipaviruses in fruit bat populations of Sulawesi and Sumba and possibly in Papua New Guinea. It appears that NiV is present where P. vampyrus occurs, such as in the fruit bat populations of Timor, but where this bat species is absent other henipaviruses may be present, as on Sulawesi and Sumba. Evidence was obtained for the presence henipaviruses in the non-Pteropid species R. amplexicaudatus and in A. celebensis. The findings of this work fill some gaps in knowledge in geographical and species distribution of henipaviruses in Australasia which will contribute to planning of risk management and surveillance activities.

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Hendra virus (HeV), a highly pathogenic zoonotic paramyxovirus recently emerged from bats, is a major concern to the horse industry in Australia. Previous research has shown that higher temperatures led to lower virus survival rates in the laboratory. We develop a model of survival of HeV in the environment as influenced by temperature. We used 20 years of daily temperature at six locations spanning the geographic range of reported HeV incidents to simulate the temporal and spatial impacts of temperature on HeV survival. At any location, simulated virus survival was greater in winter than in summer, and in any month of the year, survival was higher in higher latitudes. At any location, year-to-year variation in virus survival 24 h post-excretion was substantial and was as large as the difference between locations. Survival was higher in microhabitats with lower than ambient temperature, and when environmental exposure was shorter. The within-year pattern of virus survival mirrored the cumulative within-year occurrence of reported HeV cases, although there were no overall differences in survival in HeV case years and non-case years. The model examines the effect of temperature in isolation; actual virus survivability will reflect the effect of additional environmental factors