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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

An omni-directional design tool for series hybrid electric vehicle design

Shidore, Neeraj Shripad 17 February 2005 (has links)
System level parametric design of hybrid electric vehicles involves estimation of the power ratings as well as the values of certain parameters of the components, given the values of the performance parameters. The design is based on certain mathematical equations or ‘design rules’, which relate the component parameters and the performance parameters. The flow of the design algorithm is uni-directional and fixed, and cannot be altered. This thesis proposes a new method for such parametric design, called omni- directional design, which does not have a fixed sequence like the conventional design, but can start with any parameters of the designer’s choice. The designer is also able to specify the input parameters over a range, instead of a point (one, fixed value) input. Scenarios having a point input, but values of an output which can vary over a range for the point input, can also be studied.
22

Detecção do vírus da hepatite E em fezes de suínos abatidos sob inspeção sanitária / Detection of hepatitis E virus in swine feces slaughtered under sanitary inspection

Bertolini, Pedro Mady 20 November 2017 (has links)
Submitted by PEDRO MADY BERTOLINI null (pedro.bertolini@hotmail.com) on 2017-12-05T17:54:38Z No. of bitstreams: 1 DISSERTAÇÃO FINAL.pdf: 846707 bytes, checksum: 4fef262520629daeeadbe842680821eb (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2017-12-06T13:11:13Z (GMT) No. of bitstreams: 1 bertolini_pm_me_bot.pdf: 846707 bytes, checksum: 4fef262520629daeeadbe842680821eb (MD5) / Made available in DSpace on 2017-12-06T13:11:13Z (GMT). No. of bitstreams: 1 bertolini_pm_me_bot.pdf: 846707 bytes, checksum: 4fef262520629daeeadbe842680821eb (MD5) Previous issue date: 2017-11-20 / O vírus da hepatite E (HEV) é um importante problema para a saúde pública e uma das principais causas de hepatite entérica em todo o mundo, podendo ser transmitido pelo consumo de carne suína contaminada. O trabalho teve por objetivos avaliar a prevalência do HEV em suínos de criações intensivas e tecnificadas, abatidos em matadouro-frigorífico sob Inspeção Sanitária. Foram coletadas 140 amostras de fezes de suínos de 14 propriedades distintas dos estados de São Paulo e Santa Catarina. As técnicas de diagnósticos moleculares nas amostras de fezes foram Nested RT-PCR e sequenciamento de Sanger para identificação da presença do vírus da hepatite E e o genótipo para elucidar os dados epidemiológicos. Os suínos não apresentaram doenças ou sinais clínicos no exame ante mortem e no exame post mortem. Os fígados não apresentaram lesões macroscópicas e contaminações gastrointestinais visíveis, portanto, as vísceras e carcaças foram destinadas ao consumo humano. Foram identificados 1,4% de suínos infectados pelo HEV genótipo 3. O vírus da Hepatite E, genótipos 3 e 4 tem caráter zoonótico, podendo gerar grande impacto na Saúde Pública. Diante disso, deve-se haver cuidados na manipulação de produtos possivelmente contaminados pelo HEV, evitando assim a contaminação cruzada, e, também, tratando termicamente a carne e derivados de suínos, a fim de garantir a inocuidade alimentar. / Hepatitis E virus (HEV) is a major public health problem and one of the leading causes of enteric hepatitis worldwide and can be transmitted through the consumption of contaminated pork. The objective of this study was to evaluate the prevalence of HEV in pigs from intensive and technified farms slaughtered at a slaughterhouse under Sanitary Inspection. A total of 140 swine feces samples were collected from 14 different properties in the states of São Paulo and Santa Catarina. Molecular diagnostic techniques in faecal samples were Nested RT-PCR and Sanger sequencing to identify the presence of hepatitis E virus and the genotype to elucidate epidemiological data. The pigs had no disease or clinical signs on antemortem and post-mortem examination. The livers did not present macroscopic lesions and visible gastrointestinal contaminations, therefore the viscera and carcasses were destined for human consumption. A total of 1.4% of HEV genotype 3 infected pigs were identified. The hepatitis E virus, genotypes 3 and 4, is zoonotic in nature and can have a great impact on public health. In view of this, care must be taken in the handling of products possibly contaminated by HEV, thus avoiding cross-contamination, and also by thermally treating meat and pork products in order to guarantee food safety.
23

Development And Validation Of A Grade Adaptive Regeneration Strategy For A Parallel Hybrid Vehicle

Young, Matthew Tyler 08 August 2009 (has links)
As requirements related to vehicle fuel economy and emissions continue to increase, automakers are developing complex hybrid powertrain control systems to meet these requirements. With the increase in powertrain complexity and performance requirements of a hybrid vehicle, embedded control systems have become an integral part of these vehicles. A hybrid’s ability to recapture energy normally lost as heat during braking situations can account for an increase in efficiency of up to 28%. This study explores the use of a grade adaptive regeneration strategy for improving a hybrid vehicle’s energy recapture capability. The concept of the grade adaptive regeneration strategy was developed using a computer aided simulation model and then implemented on the Mississippi State University Challenge X hybrid vehicle. The real-time performance of the system was evaluated through chassis dynamometer and on-road tests. Substantial improvements over the native hybrid control strategy, including fuel-economy and energy recapture, have been achieved.
24

Efeitos do tratamento com a Hev b 13, extraída do látex natural de Hevea brasilienis, na resposta inflamatória de ratos com sepse / Effects of treatment with Hev b 13 protein, extracted from Hevea brasiliensis latex, on the inflammatory response of septic rats

Araújo, Lilhian Alves de 06 March 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-27T14:12:27Z No. of bitstreams: 2 Tese - Lilhian Alves de Araújo - 2017.pdf: 5322101 bytes, checksum: 57793fec5ba7f799bab9153daa5b7952 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-27T14:41:27Z (GMT) No. of bitstreams: 2 Tese - Lilhian Alves de Araújo - 2017.pdf: 5322101 bytes, checksum: 57793fec5ba7f799bab9153daa5b7952 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-27T14:41:27Z (GMT). No. of bitstreams: 2 Tese - Lilhian Alves de Araújo - 2017.pdf: 5322101 bytes, checksum: 57793fec5ba7f799bab9153daa5b7952 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-06 / Sepsis is an infectious disease characterized by severe systemic inflammatory response. Rupture of the complex equilibrium between inflammatory mediators in the acute phase of the disease leads to exacerbated production of proinflammatory cytokines, with consequent hypotension, increased capillary permeability, organ lesions and death. Recent research using the Hev b 13 protein derived from natural Hevea brasiliensis (rubber tree) latex has demonstrated important anti-inflammatory and immunomodulating effects. The aim of this study was to investigate the effects of Hev b 13 on the systemic and tissue inflammatory response of septic rats. To that end, cecal ligation and puncture (CLP) was performed on male Wistar rats and after six hours, the animals were randomized into groups and subcutaneously treated with doses of 0.5; 2.0 and 3.0 mg/Kg of Hev b 13. Next, the animals were subdivided into three different times (1, 6 and 24 hours after treatment) for blood sample collection and euthanasia with removal of the lungs and liver. Leukocytes, tumor necrosis factor- alpha (TNF-α) plasma and tissue levels, interleukin (IL)-6, IL-10, and IL-4 and histological slides were analyzed. The results demonstrated that treatment with the Hev b 13 protein prompted a significant decline in total and differential leukocytes, as well as the production of TNF-α and IL-6, associated with an increase in IL-10 and IL-4 in plasma and lung tissue. Moreover, it restricted the morphopathological changes found in the lungs, including neutrophil infiltration, swelling and alveolar thickening. In the liver, it increased IL-10 production and inhibited TNF-α and IL-6, in addition to reducing hemorrhage, sinusoidal inflammatory infiltrates and hydropic degeneration in histological assessment. We conclude that Hev b 13 displays anti-inflammatory and immunomodulating activity capable of attenuating lung and liver lesions in rats during acute sepsis, with potential for clinical applications. / Sepse é uma doença infecciosa caracterizada por uma resposta inflamatória sistêmica grave. A ruptura do complexo equilíbrio entre os mediadores inflamatórios na fase aguda da doença leva a uma produção exacerbada de citocinas pró-inflamatórias, com conseguinte hipotensão, aumento da permeabilidade capilar, lesões de órgãos e morte. Pesquisas recentes utilizando a Hev b 13, proteína derivada do látex natural da Hevea brasiliensis (seringueira), tem demonstrado importantes efeitos anti-inflamatórios e imunomoduladores. O objetivo deste estudo foi investigar os efeitos da Hev b 13 na resposta inflamatória sistêmica e tecidual de ratos com sepse. Para isso, foi realizado ligadura e perfuração do ceco (LPC) em ratos machos Wistar e, após seis horas, os animais foram randomizados em grupos e tratados com as doses 0,5; 2,0 e 3,0 mg/Kg de Hev b 13 subcutâneo. Posteriormente, subdividiu-se os animais em três tempos diferentes (1, 6 e 24 horas após os tratamentos) para coleta de amostras sanguíneas e eutanásia com remoção dos pulmões e fígado. Foram analisados os leucócitos, concentrações plasmáticas e teciduais de fator de necrose tumoral-α (TNF-α), interleucina (IL) 6, IL- 10, IL-4 e lâminas histológicas. Os resultados demonstraram que no tratamento com a proteína Hev b 13 houve redução significativa dos leucócitos totais e diferenciais bem como na produção de TNF-α e IL-6, associado ao aumento de IL-10 e IL-4 no plasma e tecido pulmonar. Além disso, restringiu as alterações morfopatológicas encontradas nos pulmões, incluindo infiltrado de neutrófilos, edema e espessamento alveolar. No fígado, aumentou a produção de IL-10 e inibiu TNF-α e IL-6, além de reduzir hemorragia, infiltrado inflamatório sinusoidal e degeneração hidrópica na avaliação histológica. Concluímos que a Hev b 13 possui atividade anti-inflamatória e imunomoduladora capaz de atenuar lesões nos pulmões e fígado de ratos durante a sepse aguda, com potencialidades para aplicabilidade clínica.
25

Cross-Species Infection and Characterization of Avian Hepatitis E Virus

Sun, Zhifeng 28 January 2005 (has links)
As novel or variant strains of HEV continue to evolve rapidly both in humans and other animals, it is important to develop a rapid pre-sequencing screening method to select field isolates for further molecular characterization. Two heteroduplex mobility assays (HMA) were developed to genetically differentiate field strains of swine HEV and avian HEV from known reference strains. It was shown that the HMA profiles generally correlate well with nucleotide sequence identities and with phylogenetic clustering between field strains and the reference swine HEV or avian HEV strains. Therefore, by using different HEV isolates as references, the HMA developed in this study can be used as a pre-sequencing screening tool to identify variant HEV isolates for further molecular epidemiological studies. Our previous study showed that avian HEV antibody is prevalent in apparently healthy chickens. A prospective study was conducted on a known seropositive but healthy chicken farm. Avian HEV was identified from the healthy chicken flock. Avian HEV isolates recovered from the healthy chicken share 70-97% nucleotide sequence identities with those isolates which cause hepatitis-splenomegaly (HS) syndrome based on partial helicase and capsid gene regions. Recovery of identical viruses from the experimentally inoculated chickens in the subsequent transmission study further confirmed our field results. The capsid gene of avian HEV isolates from chickens with HS syndrome were also characterized and found to be heterogeneic, with 76-100% nucleotide sequence identities to each other. The study indicates that avian HEV is enzootic in chicken flocks and spread subclinically among chicken populations, and that the virus is heterogeneic. As HEV can not be propagated <i>in vitro</i>, in order to further characterize avian HEV, an infectious viral stock with a known infectious titer must be generated. Bile and feces collected from specific-pathogen-free (SPF) chickens experimentally infected with avian HEV were used to prepare an avian HEV infectious stock. The infectivity titer of this infectious stock was determined, by intravenously inoculating one-week old SPF chickens, to be 5 x 10<sup>4.5</sup> 50% chicken infectious doses (CID₅₀) per ml. Seroconversion, viremia as well as fecal virus shedding were observed in the inoculated chickens. Contact control chickens also became infected via direct contact with inoculated ones. Avian HEV infection in chickens was found to be dose-dependent. To determine if avian HEV can infect across species, one-week old SPF turkeys were intravenously inoculated each with 10<sup>4.5</sup>(CID₅₀) of avian HEV. The inoculated turkeys seroconverted to avian HEV antibodies at 4-8 weeks postinoculation (WPI). Viremia was detected at 2-6 WPI, and fecal virus shedding at 4-7 WPI in inoculated turkeys. This is the first demonstration of cross-species infection by avian HEV. Little is known regarding the characteristics of the small ORF3 protein largely due to the lack of a cell culture system for HEV. To characterize the small protein, the ORF3 proteins of avian HEV and swine HEV were expressed in <i>Escherchia coli</i>, and purified by BugBuster His-Bind Purification System. Western blot analysis showed that avian HEV ORF3 protein is unique and does not share common antigenic epitopes with those of swine HEV and human HEV. However, swine HEV (genotype 3) and human HEV (genotype 1) ORF3 proteins cross-react with each other antigenically. To determine if the ORF3 protein is a virion protein, infectious stocks of avian HEV and swine HEV were first generated in SPF chickens and pigs, respectively. Virions were subsequently purified by sucrose density gradient centrifugation and virion proteins were characterized by SDS-PAGE and Western blot analysis. Two major forms of ORF2 proteins of avian HEV were identified: a 56 kDa and an 80 kDa proteins. Multiple immunoreactive forms of ORF2 proteins of swine HEV were also observed: 40 kDa, 53 kDa, 56 kDa and 72 kDa. However, the ORF3 protein was not detected from the native virions of avian HEV or swine HEV. These findings provide direct evidence that ORF2 indeed encodes a structural protein of HEV, whereas ORF3 does not. To search for other potential animal reservoirs for HEV, the prevalence of IgG anti-HEV antibody was determined in field mice caught in chicken farms to assess the possibility of mice as a potential reservoir for HEV infection in chickens. Three different recombinant HEV antigens derived from avian HEV, swine HEV, and human HEV were used in the ELISA assays. The anti-HEV seropositive rates in wild field mice (<i>Mus musculus</i>), depending upon the antigen used, are 15/76 (20%), 39/74 (53%), and 43/74 (58%), respectively. HEV RNA was also detected from 29 fecal and/or serum samples of mice. The HEV sequences recovered from field mice shared 72-100% nucleotide sequence identities with each other, 73-99% sequence identities with avian HEV isolates, and 51-60% sequence identities with representative strains of swine and human HEVs. However, attempts to experimentally infect laboratory mice (Mus musculus) with the PCR-positive fecal materials recovered from the wild field mice were unsuccessful. We also attempted to experimentally infect 10 Wistar rats each with avian HEV, swine HEV, and an US-2 strain of human HEV, respectively. However, the inoculated rats did not become infected as evidenced by the lack of viremia, virus shedding in feces or seroconversion. These data suggest that mice caught in chicken farms are infected by a HEV-like virus, but additional work is needed to determine the origin of the mouse virus as well as the potential role of rodents in HEV transmission. In summary, we developed two HMAs which are useful for differentiation and identification of variant strains of swine and avian HEVs. We genetically identified and characterized an avian HEV strain from apparently healthy chickens in seropositive flocks. We showed that avian HEV can cross species barriers and infect turkeys. Our data indicated that avian and swine HEV ORF2 genes encode structural proteins, whereas ORF3 genes do not. Evidence in this study also showed that HEV or HEV-like agent exists in field mice on a chicken farm. / Ph. D.
26

Thermal behaviour of Li-ion cell : Master Thesis project at Volvo GTT ATR / Termiskt beteende av Li-jon celler

MALTSEV, TIMOFEY January 2012 (has links)
Examensarbetet gjordes på Volvo Group Trucks Technology. Målet med arbetet var att studeravärmeutveckling i Li-jon cell för hybrid- och elbilar, HEV och EV. Battericeller undersöktesunder sina normala arbetsförhållanden och vid förstörande prov. Undersökningen baserades påcellernas yttemperatur. Arbetet beskrev cellernas beteende och syftade att vara ett underlag förkonstruktörer av batterisystem.En litteraturstudie gjordes för att studera faktorer som påverkar värmeutvecklingen. Sedananalyserades källor till samtliga faktorer. En moduleringsmetod för analys av cellensvärmeeffektivitet togs fram. Miljöpåverkan och ekonomiska aspekter av batterier undersöktes.Tre tester togs fram för att undersöka värmeutvecklingsfaktorer på fem celler. De flestafaktorerna var externa såsom laddning och urladdning, puls och kontinuerlig ström ochomgivningstemperatur. En infraröd kamera användes vid experimenten.Testerna visade hur olika faktorer påverkade cellernas temperatur. Vidare analys av källor visadekritiska områden i cellernas konstruktion.Förstörande värmeprov gjordes på tre par av celler. Dessa värmdes upp till 300°C vilketorsakade ”thermal runaway”. I vissa fall gick temperaturen över 600°C och celler fattade eld.Olika kemiska sammansättningar och uppbyggnad av cellerna gjorde att de betedde sig olika vidgenomförda tester.Testerna visade att olika celler presterade olika vid liknande testförhållanden. Därför är detviktigt att ta fram specifikationer för användningsförhållanden för att välja ut en cell för ettbatterisystem. Sedan kan prestandan av olika celler jämföras och effektivitet kan utvärderas församma belastningscyklar.Thermal Management System kan förhöja batteriets effektivitet och måste designas medanvändningsförhållanden i åtanke. Batteriernas säkerhet är väldigt viktig och människor får inteskadas av batterier. Därför måste säkerheten finnas i åtanke i alla steg av batteridesign.Arbetets resultat blev en sammanfattning av viktiga faktorer och specifikationer för batteridesignsom baserades på värmeutvecklingen. Samtliga riktlinjer sammanfattades i Appendix 5. / Master thesis work was done at Volvo Group Trucks Technology. Aim of the project was tostudy thermal behaviour of Li-ion battery for hybrid and electric vehicles, HEVs and EVs.Battery cells were tested in regular working conditions and abuse conditions. Surfacetemperature of cells was chosen for studying heat evolution.A literature study was conducted to research factors that influence cell temperature. Analysis ofsources of these factors was then performed. A modelling method for analyzing cell thermalefficiency was designed. Sustainability and economics aspects of batteries were also studied.When factors were established three tests were designed to study their effects. Five cells werestudied. Tests mainly examined external factors such as charge and discharge, pulse andcontinuous current, ambient temperature to name a few. An infrared camera was used.Study showed how different factors influenced cell temperature. Further analysis of sourcespointed out some hot spots of cell designs.Thermal abuse test were performed on three pairs of cells. Cells were heated up to 300°C andwent through thermal runaway which in some cases increased temperatures up to 660°C in lessthan a second and caused fire. Different cell chemistries and cell designs reacted differently tothe abuse conditions.A conclusion was reached that cells performed differently in similar test conditions. Whendesigning a battery system a set of specifications for usage conditions is crucial for choosing acell. When conditions and load cycles are known cells can be tested and their thermal andelectrical efficiency evaluated.Thermal Management System TMS can largely enhance cell efficiency and lifecycle. Suchsystem must also be designed according to usage conditions and particular cell’s performance.Battery safety showed to be a very important factor of designing a battery system. Humans shallnot be injured by systems with batteries which must be kept in mind during design.Work resulted in summary of important factors and specifications for designing a battery systembased on cell thermal behaviour. These guidelines are presented in Appendix 5.
27

HEV fuel optimization using interval back propagation based dynamic programming

Ramachandran, Adithya 27 May 2016 (has links)
In this thesis, the primary powertrain components of a power split hybrid electric vehicle are modeled. In particular, the dynamic model of the energy storage element (i.e., traction battery) is exactly linearized through an input transformation method to take advantage of the proposed optimal control algorithm. A lipschitz continuous and nondecreasing cost function is formulated in order to minimize the net amount of consumed fuel. The globally optimal solution is obtained using a dynamic programming routine that produces the optimal input based on the current state of charge and the future power demand. It is shown that the global optimal control solution can be expressed in closed form for a time invariant and convex incremental cost function utilizing the interval back propagation approach. The global optimality of both time varying and invariant solutions are rigorously proved. The optimal closed form solution is further shown to be applicable to the time varying case provided that the time variations of the incremental cost function are sufficiently small. The real time implementation of this algorithm in Simulink is discussed and a 32.84 % improvement in fuel economy is observed compared to existing rule based methods.
28

Aspects épidémiologiques et caractérisation moléculaire des souches du virus de l’hépatite E (VHE) au Burkina Faso / EPIDEMIOLOGICAL AND MOLECULAR CHARACTERIZATION OF HEPATITIS E VIRUS (HEV) STRAINS IN BURKINA FASO

Traoré, Kuan Abdoulaye 02 June 2015 (has links)
Le virus de l’hépatite E (VHE) est l’agent causal d’une partie des hépatites aigues ou fulminantes qui surviennent essentiellement dans les pays en voie de développement (Afrique, Asie) ou le VHE de génotype 1 semble présenter un profil endémique ponctué de bouffées épidémiques souvent liées à des déplacements de populations (catastrophe climatique ou conflits) (Lui et al., 2013). Récemment il a été montré que ce virus était largement distribué dans des réservoirs animaux (génotype 3 et 4) et la cause d’un grand nombre d’infections zoonotiques aussi bien dans les pays du nord que du sud. Dans la plupart des cas, il s'agit d'une infection spontanément résolutive avec une clairance virale rapide, mais il peut évoluer vers des formes plus sévères avec un niveau de mortalité variant de 1 à 4% dans la population générale et à près de 20% chez la femme enceinte lors des flambées épidémiques (OMS, 2014). Au Burkina Faso, très peu de données existent sur la prévalence chez l’homme, l'épidémiologie moléculaire du VHE ou la présence de ce virus dans le réservoir animal principal que constituent les porcs. De plus, l’ignorance de la population quant aux causes de cette infection d’origine alimentaire, est un facteur de risque qu’on ne peut pas ignorer. L’objectif de ce travail est donc d’améliorer notre connaissance sur cet agent des hépatites. La première partie de notre étude s’est consacrée à l’évaluation de la séroprévalence du VHE chez les donneurs de sang et les femmes venant en consultation prénatale à Ouagadougou. Au total plus de 1700 échantillons de sérums de volontaires ont été collectés dans les banques de sang et centres médicaux: entre 2010 et 2012, sur les 178 donneurs de sang et 189 femmes enceintes testés, 19,1% [IC95, 13,3-24,9%] et 11,6% [IC95, 7,1-16,2%] étaient respectivement positifs aux IgG anti-VHE. Ces taux élevés sont peut-être associé au faible statut socioéconomique et à l’absence de réseaux d’assainissement des eaux (Traoré et al., 2012). En 2014, 3,19% [IC95, 1,70-4,68%] des 533 donneurs de sang testé sont positifs pour des IgM anti-VHE. Ces résultats montrent un risque résiduel transfusionnel non négligeable associé à une transmission à bas bruit et confirme l’intérêt d’identifier la ou les sources de ce virus. La seconde partie de ce travail a été de vérifier le rôle d’une source zoonotique des infections à VHE, via l’évaluation du VHE (par sérologie et typage moléculaire après PCR) dans le réservoir potentiel que sont les porcs et la population à risques exposé à ce réservoir (bouchers et éleveurs). Pour cela nous avons réalisé un recensement des sites de ventes de porcs et évalué la consommation d’animaux. Un taux de séroprévalence de 76% [IC95, 67,6-84,4%] a été mesuré dans une cohorte de 100 bouchers de Ouagadougou avec un facteur de risque de séropositivité 3 fois plus élevé par rapport à la population générale (OR = 3,46 [95%CI 2,85 – 4,21] p <0.001). Les IgG anti-VHE chez les porcs abattus ont été estimés à 80% IC95 [72-87%]. Cette forte prévalence confirme une circulation silencieuse du VHE dans l’élevage porcin au Burkina Faso comme en témoigne l'échantillon positif de foie pour l’ARN VHE qui soutient fermement le risque de zoonose. L’analyse des séquences des produits de PCR des foies de porcs positifs pour VHE a révélé la présence de VHE génotype 3 et 99,8 % d'homologie avec les souches Yaounde et Madagascar. En conclusion, notre étude, la première caractérisation moléculaire des souches du VHE au Burkina, montre la présence de souches VHE génotype 3 dans des régions ou seul le génotype 1 avait été identifié jusqu’alors (Tchad, Maroc). L’évaluation du risque transfusionnel associé nécessite des études complémentaires afin d’évaluer le bénéfice/coût de l'ajout de dépistage du VHE dans les examens de routines des banques de sang, afin de garantir la sécurité du receveur de sang. / The hepatitis E virus (HEV) is causative agent several acute or fulminant hepatitis which mainly occur in developing countries where HEV genotype 1 or 2 appears to have a endemic profile punctuated with epidemic outbreaks (Africa, Asia) (Lui et al., 2013). Genotype 3 and 4 distributed widely in animal reservoirs, were the cause many zoonotic infection in northern and southern countries. In most cases, it is a self-limited infection with rapid viral clearance, but it can evolve into more severe forms with a mortality level ranging from 1 to 4% in the general population to nearly 20% in pregnancy during outbreaks (WHO, 2014). In Burkina Faso, very little epidemiological data are available on HEV. The objective of this work is to improve our understanding of this agent hepatitis. The first part of our study was devoted to the evaluation HEV seroprevalence among blood donors and women attending antenatal care in Ouagadougou. In total more than 1,700 volunteers serum samples were collected in blood banks and medical centers in Burkina Faso. Between 2010 and 2012 on 178 blood donors and 189 pregnant women tested, 19.1% [CI95, 13.3-24.9%] and 11.6% [CI95, 7.1-16.2%], were respectively positive for anti-HEV IgG. These high rates in the general population may be associated a low income and the poor hygienic status (Traoré et al., 2012). In 2014, 3.19% [CI95, 1.70-4.68%] on 525 blood donors tested, were positive for anti-HEV IgM. These results indicate a residual risk for transfusion, probably associated with silent infections and confirm the importance to identify the sources of the virus. The second part of this work was 1) to assess HEV infection among humans in Burkina Faso by exploring the HEV seroprevalence in a high risk population, i.e., butchers; 2) to explore a possible pig-to-human zoonotic transmission cycle by assessing the HEV seroprevalence in slaughter swine; and 3) to identify the genotype of HEV circulating in pigs. The global HEV prevalence among Ouagadougou butchers was estimated to 76%, CI95 [67, 63–84.37%] with a significant risk factor, 3 times higher compared with the general population (OR = 3.46 [95%CI 2.85 - 4.21] p <0.001). IgG anti-HEV in pigs older than 6 months of age were estimated at 80% CI95 [72-87%]. This high prevalence confirms the presence and active circulation HEV among domestic pigs in Burkina Faso as evidenced by the positive sample of liver for HEV RNA which strongly supports the risk of zoonosis. Phylogenetic analyses revealed that genotype 3 HEV is circulating among swine population in Burkina. A similarity >98% was found between swHEV-BF from Yaounde and Madagascar. This data showed for the first time the role of swine in introduction of new HEV in African population. In conclusion, these results latter sign a persistent introduction of HEV infection in the population and hence deserved to be taken in account in transfusion associated risk. Further assessments of the transfusion risk associated require an evaluation of the cost/benefit ratio for the addition of routine HEV RNA screening to the panel of tests on donated blood, to guarantee transfusion safety for the recipient.
29

Optimization of a plug-in hybrid electric vehicle

Golbuff, Sam 22 May 2006 (has links)
A plug-in hybrid electric vehicle (PHEV) is a vehicle powered by a combination of an internal combustion engine and an electric motor with a battery pack. The battery pack can be charged by plugging the vehicle into the electric grid or from using excess engine power. A PHEV allows for all electric operation for limited distances, while having the operation and range of a conventional hybrid electric vehicle on longer trips. A PHEV design with design parameters electric motor size, engine size, battery capacity, and battery chemistry type, is optimized with minimum cost as a figure of merit. The PHEV is required to meet a fixed set of performance constraints consisting of 0-60 mph acceleration, 50-70 mph acceleration, 0-30 mph acceleration in all electric operation, top speed, grade ability, and all electric range. The optimization is carried out for values of all electric range of 10, 20, and 40 miles. The social and economic impacts of the optimum designs in terms of reduced gasoline consumption and carbon emissions reduction are calculated. Argonne National Laboratorys Powertrain Systems Analysis Toolkit is used to simulate the performance and fuel economy of the PHEV designs. The costs of different PHEV components and the present value of battery replacements over the vehicles life are used to determine the designs drivetrain cost. The resulting optimum PHEVs are designs using lead acid battery type. The optimum design parameter values are all determined by a single controlling performance constraint. The PHEV designs show a 63% to 80% reduction in gasoline consumption and a 53% to 47% reduction in CO2 emissions. The PHEV designs have an annual gas savings of $696 to $643 per year over the average sedan meeting the 27.5 mpg CAFE standards.
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Efekt přítlaku vyvozovaného na elektrodový systém olověného akumulátoru s experimentálními elektrodami / The effect of pressure on the electrode system in lead acid batteries with experimental electrodes

Zabloudil, Ondřej January 2014 (has links)
This Master’s thesis deals with the issue of lead-acid batteries, which are used in hybrid electric vehicles. The lead-acid batteries works in mode PSoC. In this mode occurs to degradation mechanisms at negative electrodes. These degradation mechanisms reduce the battery life. The practical part of Master’s thesis describes the production and a compilation of experimental cells and experimental part examines the characteristics of lead-acid batteries with the pressure to the electrode system.

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