Global ETD Search

11	Desenvolvimento e avaliação de nanoemulsões com óleos de Carapa guianensis e Copaifera sp. e estudo da ação repelente frente a Aedes aegypti. / Development and evaluation of nanoemulsions with Carapa guianensis and Copaifera sp. oil, and evaluation of repellency against Aedes aegypti Oliveira, Bianca Rodrigues de 24 October 2008 (has links) As doenças transmitidas por mosquitos representam uma das maiores causas de morbidade e mortalidade em todo o mundo, principalmente em países tropicais. O uso tópico de repelentes em determinadas situações torna-se a única alternativa para evitar o ataque por estes artrópodes. Os óleos de andiroba (Carapa guianensis) e copaíba (Copaifera sp.) possuem relatos de atividade repelente de insetos, podendo representar uma alternativa segura ao uso de repelentes sintéticos que apresentam riscos de toxidade em determinados casos. O objetivo desta pesquisa foi desenvolver nanoemulsões O/A, utilizando como fase oleosa os óleos de copaíba e andiroba, e testar in vivo a atividade repelente das mesmas frente ao mosquito Aedes aegypti, realizando um estudo comparativo com repelente comercial a base de DEET. Ensaios para avaliar os parâmetros físico-quimicos envolvidos no processo de obtenção das nanoemulsões, e estudos de sua estabilidade preliminar, também foram realizados. Os resultados apontam a viabilidade do método de emulsificação utilizando baixa energia na formação de nanoemulsões. A temperatura, velocidade de agitação, ordem de adição dos componentes e quantidade de tensoativo na formulação, demonstraram ser fatores críticos no processo. Foi possível obter três nanoemulsões estáveis com tamanho de glóbulos inferior a 300nm, sendo uma com 15% de óleo de andiroba; outra contendo 10% de óleo de copaíba e a terceira associando 10% de andiroba e 5% de copaíba. No ensaio repelente utilizando voluntários humanos, foi constatado que as nanoemulsões compostas de óleo de andiroba e óleo de andiroba adicionado de óleo de copaíba são capazes de repelir mosquitos Aedes aegypti por um período de 30 minutos, sendo estes resultados estatisticamente significativos em relação ao grupo controle. / Mosquito-borne diseases remain a major source of illness and death worldwide, particularly in tropical countries. Mosquito repellents may be one of the most effective tools for protecting humans from vector-borne diseases. In many circumstances, applying repellent to the skin may be the only feasible way to protect against insect bites. The oils from andiroba (Carapa guianensis seed oil) and copaíba (Copaifera oil) have been studied as possible mosquito repellents. These products can be represents a safe alternative in the use of synthetic repellent, that have toxic risks in some cases. The goals of this research were to development O/A nanoemulsion using andiroba seed oil and copaíba oil and test their repellent action in vivo against bites Aedes aegypti. This study compares the repel effectiveness of nanoemulsions developed in relation to the market product of DEET. Assays to evaluate the parameters involved physicist-chemistries in the process of attainment of the nanoemulsions, and studies of its preliminary stability, had been also carried through. The results showed viability of the emulsification method using low energy in the formation of nanoemulsions. The temperature, speed of agitation, order of addition of the components and amount of surfactant in the formulation, had demonstrated to be critical factors in the process. In this study, it was possible get three stable nanoemulsion with droplets size less than 300nm, using: 15% andiroba seed oil; 10% copaiba oil and mix of andiroba seed oil (10%) and copaíba oil (5%). The repellent test with human voluntaries proves that nanoemulsions with andiroba seed oil, and the mix of andiroba seed oil and copaiba oil, are able to repel Aedes aegypti for 30 minutes period, witch are statistic signification compared to the control group. Aedes aegypti Aedes aegypti andiroba seed oil Carapa guianensis Carapa guianensis copaíba oil Copaifera sp. Copaifera sp. deet deet inversão de fases nanoemulsão nanoemulsion óleo de andiroba óleo de copaíba phase inversion repelente repellents
12	Desenvolvimento e avaliação de nanoemulsões com óleos de Carapa guianensis e Copaifera sp. e estudo da ação repelente frente a Aedes aegypti. / Development and evaluation of nanoemulsions with Carapa guianensis and Copaifera sp. oil, and evaluation of repellency against Aedes aegypti Bianca Rodrigues de Oliveira 24 October 2008 (has links) As doenças transmitidas por mosquitos representam uma das maiores causas de morbidade e mortalidade em todo o mundo, principalmente em países tropicais. O uso tópico de repelentes em determinadas situações torna-se a única alternativa para evitar o ataque por estes artrópodes. Os óleos de andiroba (Carapa guianensis) e copaíba (Copaifera sp.) possuem relatos de atividade repelente de insetos, podendo representar uma alternativa segura ao uso de repelentes sintéticos que apresentam riscos de toxidade em determinados casos. O objetivo desta pesquisa foi desenvolver nanoemulsões O/A, utilizando como fase oleosa os óleos de copaíba e andiroba, e testar in vivo a atividade repelente das mesmas frente ao mosquito Aedes aegypti, realizando um estudo comparativo com repelente comercial a base de DEET. Ensaios para avaliar os parâmetros físico-quimicos envolvidos no processo de obtenção das nanoemulsões, e estudos de sua estabilidade preliminar, também foram realizados. Os resultados apontam a viabilidade do método de emulsificação utilizando baixa energia na formação de nanoemulsões. A temperatura, velocidade de agitação, ordem de adição dos componentes e quantidade de tensoativo na formulação, demonstraram ser fatores críticos no processo. Foi possível obter três nanoemulsões estáveis com tamanho de glóbulos inferior a 300nm, sendo uma com 15% de óleo de andiroba; outra contendo 10% de óleo de copaíba e a terceira associando 10% de andiroba e 5% de copaíba. No ensaio repelente utilizando voluntários humanos, foi constatado que as nanoemulsões compostas de óleo de andiroba e óleo de andiroba adicionado de óleo de copaíba são capazes de repelir mosquitos Aedes aegypti por um período de 30 minutos, sendo estes resultados estatisticamente significativos em relação ao grupo controle. / Mosquito-borne diseases remain a major source of illness and death worldwide, particularly in tropical countries. Mosquito repellents may be one of the most effective tools for protecting humans from vector-borne diseases. In many circumstances, applying repellent to the skin may be the only feasible way to protect against insect bites. The oils from andiroba (Carapa guianensis seed oil) and copaíba (Copaifera oil) have been studied as possible mosquito repellents. These products can be represents a safe alternative in the use of synthetic repellent, that have toxic risks in some cases. The goals of this research were to development O/A nanoemulsion using andiroba seed oil and copaíba oil and test their repellent action in vivo against bites Aedes aegypti. This study compares the repel effectiveness of nanoemulsions developed in relation to the market product of DEET. Assays to evaluate the parameters involved physicist-chemistries in the process of attainment of the nanoemulsions, and studies of its preliminary stability, had been also carried through. The results showed viability of the emulsification method using low energy in the formation of nanoemulsions. The temperature, speed of agitation, order of addition of the components and amount of surfactant in the formulation, had demonstrated to be critical factors in the process. In this study, it was possible get three stable nanoemulsion with droplets size less than 300nm, using: 15% andiroba seed oil; 10% copaiba oil and mix of andiroba seed oil (10%) and copaíba oil (5%). The repellent test with human voluntaries proves that nanoemulsions with andiroba seed oil, and the mix of andiroba seed oil and copaiba oil, are able to repel Aedes aegypti for 30 minutes period, witch are statistic signification compared to the control group. Aedes aegypti Carapa guianensis Copaifera sp. deet inversão de fases nanoemulsão óleo de andiroba óleo de copaíba repelente Aedes aegypti andiroba seed oil Carapa guianensis copaíba oil Copaifera sp. deet nanoemulsion phase inversion repellents
13	ETUDE DU MODE D'ACTION NEUROTOXIQUE D'UN REPULSIF, LE DEET UTILISE SEUL ET EN ASSOCIATION AVEC UN INSECTICIDE SUR L'ACETYLCHOLINESTERASE DES DUM NEURONES D'UN INSECTE LA BLATTE PERIPLANETA AMERICANA Mohamed, Aly Ahmed Abd-Ella 31 March 2011 (has links) (PDF) Le DEET (N, N-diéthyl-m-toluamide), est connu comme le répulsif le plus utilisé au monde. Bien qu'il soit efficace contre un large groupe d'arthropodes, son mode d'action exact et sa cible moléculaire ne sont pas encore connus précisément. Grâce à l'utilisation des techniques d'électrophysiologie (patch-clamp et oil-gap), d'imagerie calcique et biochimique, nous avons étudié le mode d'action du DEET sur des cellules neurosécrétrices identifiées, les DUM neurones de la blatte Periplaneta americana. Le DEET, à forte concentration, inhibe l'activité de l'acétylcholinestérase (AChE) au niveau du DUM neurone. A faible concentration, il induit une augmentation de la concentration en calcium intracellulaire via l'activation des récepteurs cholinergiques de type muscariniques (mAChRs). Dans un deuxième temps, les interactions synergiques entre le DEET et le propoxur, un carbamate connu pour inhiber l'AChE, ont été étudiées. Les résultats ont révélé que les mAChRs, correspondent bien à une nouvelle cible potentielle pour le DEET et qu'ils sont impliqués dans l'effet synergique. Le DEET, à faible et à forte concentration, agit sur des sites allostériques positifs et négatifs des mAChRs respectivement. L'action du DEET sur le site allostérique positif des mAChRs est responsable de l'effet synergique via une augmentation de la concentration en calcium intracellulaire qui potentialise l'effet anti-AChE du propoxur. L'utilisation d'outils pharmacologiques sélectifs a permis l'identification de la voie de signalisation intracellulaire (PLC, PI-PLC, CaMKinase II, récepteurs IP3) impliquée dans l'effet synergique du propoxur. Les résultats présentés dans ce mémoire vont contribuer au développement de nouvelles stratégies basées sur l'utilisation de combinaisons d'insecticides de familles chimiques différentes afin de réduire les doses des traitements tout en augmentant l'efficacité. répulsifs DEET insecticides insecte DUM neurone patch-clamp calcium intracellulaire acétylcholinestérase récepteurs muscariniques modulation allostérique
14	Factors influencing arbovirus transmission: vector competence and the effects of virus infection on repellent response, oxidative stress, and glutathione-S-transferase activity Chan, Kevin Ki Fai 31 January 2020 (has links) Zika (ZIKV), La Crosse (LACV), and Cache Valley (CVV) viruses are mosquito-vectored diseases that cause significant morbidity and mortality in humans and animals. Transmission of these viruses are dependent on numerous factors including vector competence and the effects of mosquito-virus interactions. We conducted vector competence studies of local Aedes and Culex mosquitoes for ZIKV and CVV, and found that all Aedes mosquitoes were competent for CVV and only Aedes albopictus and Aedes japonicus were competent for ZIKV. Vector competence for CVV was dose-dependent, where mosquitoes orally infected with high titers developed higher transmission rates. We also found that vector competence for ZIKV was limited by midgut and salivary gland barriers. Second, we looked at the effects of LACV and ZIKV infection on repellent response in Aedes mosquitoes and found that infected mosquitoes were refractory to low concentrations of DEET, picaridin, and PMD. Increasing concentrations of the repellents to ≥10% was able to increase percent protection (%p) against infected and uninfected mosquitoes. Lastly, we determined the effects of ZIKV and LACV infection on oxidative stress and glutathione-S-transferase (GST) activity in Aedes albopictus. Virus infection had no effect on oxidative stress, but GST activity was significantly different for mosquitoes 3-days post-exposure. We found that oxidative stress levels and GST activity had an inverse relationship for infected and uninfected mosquitoes, where oxidative stress decreased and GST activity increased over the 10-day test period. This indicates that GSTs may aid in controlling byproducts of oxidative stress. The results from this entire study identified competent vectors for emerging arboviruses and demonstrated the behavioral and physiological effects of virus infection in the mosquito vector. / Doctor of Philosophy / Zika (ZIKV), La Crosse (LACV), and Cache Valley (CVV) viruses are transmitted by mosquitoes and can make humans and animals very sick. There are many biological factors that determine if a mosquito can transmit a virus and these viruses can change the biology of a mosquito. We conducted laboratory studies to see if Aedes and Culex mosquitoes can transmit ZIKV and CVV. We found that all Aedes mosquitoes were able to transmit CVV and only the Asian tiger mosquito and Asian rock pool mosquito were able to transmit ZIKV. Mosquitoes infected with high amounts of CVV developed higher transmission rates. We also found that transmission of ZIKV was limited by barriers in the mosquito midgut and salivary glands. Second, we looked at the effects of LACV and ZIKV infection on how Aedes mosquitoes respond to repellents and found that infected mosquitoes were less sensitive to low concentrations of DEET, picaridin, and PMD. Increasing concentrations of the repellents to 10% or higher was able to provide adequate protection against infected and uninfected mosquitoes. Lastly, we determined the effects of ZIKV and LACV infection on oxidative stress and glutathione-S-transferase (GST) activity in the Asian tiger mosquito. Virus infection did not change oxidative stress, but GST activity was higher in infected mosquitoes tested after 3 days after infection. We found that oxidative stress decreased and GST activity increased over the 10-day test period. This indicates that GSTs may help control damaging products from oxidative stress. The results from this entire study identified what mosquitoes were able to transmit emerging mosquito-borne viruses and demonstrated the biological effects of virus infection in the mosquitoes. Zika virus Cache Valley virus La Crosse virus vector competence repellent DEET picaridin p-methane-3 8-diol glutathione-S-transferase Aedes albopictus Aedes japonicus Aedes triseriatus
15	Students' experiences of e-learning at school Barty, Karin, kimg@deakin.edu.au,jillj@deakin.edu.au,mikewood@deakin.edu.au January 2001 (has links) The dissertation describes the experiences of senior secondary students taking an online course for the first time to further their language education. The experiences are presented from the perspective of students, of supervising teachers and the 'virtual' teacher. Issues of importance with younger learners are identified and discussed and guidelines for the conduct of online courses at school level developed. It is proposed that online courses may have a worthwhile place in school education if specific learning needs can be met using this medium. online courses students secondary level of schooling North America 1995 1997 netcourses e-learning LOTE online Key Learning Area (KLA) Languages Other Than English (LOTE) Telematics Project Department of Education Employment and training (DEET) Victorian Education Department regional centre Victoria English literature cyberschool electronic classroom Deakin University
16	The Association of Libarians in colleges of advanced education and the committee of Australian university librarians: The evolution of two higher education library groups, 1958-1997 Oakshott, Stephen Craig, School of Information, Library & Archives Studies, UNSW January 1998 (has links) This thesis examines the history of Commonwealth Government higher education policy in Australia between 1958 and 1997 and its impact on the development of two groups of academic librarians: the Association of Librarians in Colleges in Advanced Education (ALCAE) and the Committee of Australian University Librarians (CAUL). Although university librarians had met occasionally since the late 1920s, it was only in 1965 that a more formal organisation, known as CAUL, was established to facilitate the exchange of ideas and information. ALCAE was set up in 1969 and played an important role helping develop a special concept of library service peculiar to the newly formed College of Advanced Education (CAE) sector. As well as examining the impact of Commonwealth Government higher education policy on ALCAE and CAUL, the thesis also explores the influence of other factors on these two groups, including the range of personalities that comprised them, and their relationship with their parent institutions and with other professional groups and organisations. The study focuses on how higher education policy and these other external and internal factors shaped the functions, aspirations, and internal dynamics of these two groups and how this resulted in each group evolving differently. The author argues that, because of the greater attention given to the special educational role of libraries in the CAE curriculum, the group of college librarians had the opportunity to participate in, and have some influence on, Commonwealth Government statutory bodies responsible for the coordination of policy and the distribution of funding for the CAE sector. The link between ALCAE and formal policy-making processes resulted in a more dynamic group than CAUL, with the university librarians being discouraged by their Vice-Chancellors from having contact with university funding bodies because of the desire of the universities to maintain a greater level of control over their affairs and resist interference from government. The circumstances of each group underwent a reversal over time as ALCAE's effectiveness began to diminish as a result of changes to the CAE sector and as member interest was transferred to other groups and organisations. Conversely, CAUL gradually became a more active group during the 1980s and early 1990s as a result of changes to higher education, the efforts of some university librarians, and changes in membership. This study is based principally on primary source material, with the story of ALCAE and CAUL being told through the use of a combination of original documentation (including minutes of meetings and correspondence) and interviews with members of each group and other key figures. CAUL ALCAE Higher Education Australia Libraries University Universities Colleges of Advanced Education CAE History Cooperation Interest Groups Lobbying Lobby Groups Federal Government Commonwealth Government Funding Australian Vice-Chancellors' Committee AVCC AACOBS Library Association of Australia LAA ALIA CAVAL CLANN ACDP Australian Bibliographical Network ABN ALIC ACAE Australian Universities Commission AUC CACAE ACAE CTEC Tertiary Education Commission TEC DEET NSWAEC UNISON Victor CRITTENDEN Paul McNALLY Andrew OSBORN Dorothy PEAKE Jack WARD Dietrich BORCHARDT Harrison BRYAN Ted FLOWERS Allan HORTON Neil RADFORD Denis RICHARDSON Colin STEELE Eric WAINWRIGHT Frank HAMBLY Geoff ALLEN Christopher AWCOCK Judith EDWARDS John CUMMINGS Katherine CUMMINGS Axel LODEWYCKS Derek FIELDING Leonard JOLLEY Brian SOUTHWELL John SHIPP James O'BRIEN Jessie HARLEY Bill HITCHINS Lois JENNINGS John YOCKLUNN

Page generated in 0.0322 seconds