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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.
211

Aspectos epidemiológicos de Histoplasma capsulatum em morcegos em áreas urbanas do estado de São Paulo / Epidemiologic Aspects of Histoplasma capsulatum in bats from urban areas of State of São Paulo

Maria Adelaide Galvão Dias 02 December 2009 (has links)
A histoplasmose, uma micose sistêmica, é um importante problema de saúde pública, de distribuição mundial e uma infecção muito comum em regiões endêmicas. A infecção é causada pelo fungo dimórfico Histoplasma capsulatum varo capsulatum, que cresce como fungo filamentoso em solo, guano de morcegos e aves, ou como uma levedura parasitária intracelular. A ocorrência de morcegos é relatada em quase todo o mundo e estes contribuem para manutenção deste fungo na natureza. Na cidade de São Paulo, Brasil, morcegos ocorrem em todas as regiões e em várias situações: usando sótãos e forro de telhado como abrigos ou adentrando residências, entre outras. Entre agosto de 2003 a dezembro de 2008, foram encaminhados ao Setor de Micologia do Centro de Controle de Zoonoses da cidade de São Paulo 2427 morcegos. Amostras de fígado e baço desses morcegos foram removidos em condições estéreis e inoculados, ambos, em Agar infusão de cérebro e coração (BHI) e em Agar Sabouraud Dextrose, incubados a 25°C e 37°C. As colônias suspeitas foram reincubadas em Agar Mycosel e identificadas pela morfologia e pela reversão em ML-gema (Mueller Hinton Broth com L-cisteína e gema de ovo) a 37°C. O objetivo deste estudo foi estabelecer a prevalência do H. capsulatum em morcegos presentes na cidade de São Paulo e em outras cidades do Estado. Os 87 isolados de H. capsulatum (3,58%) foram todos de morcegos da família Molossidae, de hábito alimentar insetívoro, pertencentes a quatro gêneros e cinco espécies sendo 74 Molossus molossus, 10 Nyctinomops macrotis, 1 Tadarida brasiliensis, 1 Molossus rufus e 1 Eumops glaucinus. Para 3 espécies (Molossus rufus, Nyctinomops macrotis e Eumops glaucinus) trata-se do primeiro relato. Dos 2427 morcegos, 1728 morcegos eram procedentes da cidade de São Paulo (71,2%) e 699 morcegos eram originários de cidades do Estado de São Paulo (28,8%). Cinco cidades apresentaram espécimes positivos: 70 procedentes da cidade de São Paulo (80,5%) e 17 de outros municípios do Estado (19,5%): 4 de Jundiaí, 10 de Guarulhos, 2 de Osasco e 1 de Mogi Mirim. Para a análise das 61 amostras de fezes de morcegos recebidas, foram utilizadas as técnicas de inoculação em camundongo e semeadura em placa de Petri contendo meio de Agar Mycosel incubadas a 37°C. Uma amostra positiva para H. capsulatum foi isolada do Agar Mycosel. Os resultados mostram que o H.capsulatum esta presente na população de morcegos presentes em áreas urbanas do Estado de São Paulo. Este fato é importante, porque morcegos contaminados podem ser fonte de disseminação e risco para pessoas ou animais adquirirem a infecção. O conhecimento da história natural da histoplasmose em áreas urbanas pode ter um importante papel no estabelecimento de estratégias de prevenção. / Systemic histoplamosis is an important health problem worldwide and a very common infection in endemic areas. Its causative agent, the thermodimorphic fungus Histoplasma capsulatum varo capsulatum, grows in bat guano or bird droppings rich soils as filamentous fungi, or as parasitic intracellular yeast cells in hosts. Bats can be found in almost ali the world and contribute to the maintenance of this fungus in nature. In many cities in Brazil, bats are found in urban areas and in many situations: house basements and/or roofs, fallen in the soil or even inside the houses, among others. Between August 2003 and December 2008, 2,427 bats, 1,728 from São Paulo City (71.2%) and 699 from other cities from São Paulo State, were sent to the Micology Section of Centro de Controle de Zoonoses of São Paulo City. The purpose of this work was to establish the prevalence of H.capsulatum in bats of São Paulo City and other cities from São Paulo State. Samples of spleen and liver from the animais were removed in sterile conditions and inoculated in Brain Heart Infusion Agar and in Sabouraud Dextrose Agar, incubated at 25°C and 37°C. The suspicious colonies were inoculated in Mycosel Agar and were identified by the morphology, as well as by the temperature¬reversion after incubation in ML-egg yolk (Mueller Hinton Broth, with L-cysteine and hen egg yolk) at 37°C. Ali 87 positive samples (3.58%) were isolated from insectivorous bats from Molossidae family, belonging to four genus and five species: 74 samples were from the specie Molossus molossus, 10 from Nyctinomops macrotis, 1 from Molossus rufus, 1 from Tadarida brasiliensis, and 1 from Eumops glaucinus. For three of these species (Nyctinomops macrotis, Molossus rufus and Eumops glaucinus) this is the first report of H. capsulatum isolation. Seventy positive bats were from São Paulo (80.5%), ten from Guarulhos City, four from Jundiaí City, two from Os asco City and one from Mogi Mirim City. Sixty-one samples of feces were analised by mouse inoculation test and inoculation in Petri dishes containing Mycosel Agar. Our results showed that the H. capsulatum is present in bat populations Iiving in urban areas. This is an important fact since H. capsulatum contaminated bats can be a source of contamination for people or animais in contact with them. The knowledge of the natural history of histoplasmosis in urban areas may be important for the establishment of prevention strategies.
212

Vírus da raiva em morcegos insetívoros: implicações em epidemiologia molecular da diversidade dos genes codificadores da nucleoproteína e glicoproteína / Rabies virus in insectivorous bats: implications in molecular epidemiology of the diversity of genes encoding nucleoprotein and glycoprotein

Rafael de Novaes Oliveira 05 March 2009 (has links)
Com o controle da raiva nos cães do Estado de São Paulo nos últimos 20 anos, a raiva em animais silvestres, sobretudo nos quirópteros, assume crescente importância, visto que, atualmente, estes são os principais reservatórios para a raiva neste Estado. Apesar dos morcegos manterem ciclos epidemiológicos da raiva há centenas de anos, somente a partir da década de 50 a raiva em morcegos insetívoros foi reconhecida como um problema de saúde publica. Desde então foram feitos muitos avanços na compreensão da raiva nestes animais. Atualmente, o vírus da raiva (RABV) já foi detectado em 37 espécies de morcegos brasileiros, tendo sido determinadas quatro linhagens genéticas específicas associadas a quatros gênero/espécies destes morcegos, três destas exclusivas de morcegos insetívoros. Entretanto, apesar da importância da raiva em morcegos insetívoros, estudos voltados a um conhecimento mais amplo das implicações da diversidade de amostras de RABV detectadas nos mesmos aplicados à Epidemiologia Molecular são escassos. Assim, a presente investigação teve por objetivos estabelecer genealogias para amostras de RABV isoladas de diversas espécies de morcegos insetívoros do Estado de São Paulo a partir de seqüências parciais dos genes N (40 amostras) e G (45 amostras), avaliar a existência de linhagens gênero-específicas do RABV e determinar os marcadores moleculares para sua diferenciação. Foram encontradas linhagens específicas de RABV para os gêneros Myotis, Epitesicus e Nyctinomops e três prováveis linhagens circulantes nos gêneros Tadarida, Histiotus e Lasiurus. Além disso, esta pesquisa revelou marcadores moleculares de aminoácidos específicos para os gêneros Myotis, Eptesicus e Nyctinomops, contribuindo para um melhor entendimento da epidemiologia molecular da Raiva e da relação entre o RABV e gêneros diversos de quirópteros. / As a result of the control of canine rabies in São Paulo State in the last 20 years, rabies in wild animals, mainly in bats, has assumed an increasing importance as the last are currently the most important rabies reservoirs in this State. Despite the fact that bats have maintained epidemiological cycles of rabies for centuries, only in the 50s rabies in insectivorous bats was recognized as a threat for Public Health and several advances have been achieved since then for the comprehension of rabies in these animals. Rabies virus (RABV) has already been detected in 37 species of Brazilian bats and four specific genetic lineages associated to four genera/ species of bats have been determined, three of these exclusive to insectivorous bats. Nonetheless, despite the importance of insectivorous bats rabies, studies on a more comprehensive knowledge on the implications of the diversity of RABV strains detected on these are scarce. Thus, the present investigation aimed to establish genealogies for RABV strains isolated from diverse species from insectivorous bats from São Paulo State based on partial N (40 strains) and G (45 strains ) genes, assess the existence of genus-specific lineages of RABV and to determine molecular markers for its differentiation. Specific RABV lineages where found for the genera Myotis, Epitesicus and Nyctinomops and three other probable lineages circulating in the genera Tadarida, Histiotus and Lasiurus where found as well. Furthermore, this investigation revealed amino acids molecular markers for the genera Myotis, Eptesicus and Nyctinomops, contributing to a better understanding of rabies molecular epidemiology and the relationship amongst RABV and diverse genera of bats.
213

Seasonal changes in pituitary and plasma prolactin concentrations, and the role of Prolactin in the control of delayed implantation in female Miniopterus schreibersii

Bojarski, Christina January 1993 (has links)
Mammotropes were successfully identified in the anterior pituitary gland of Miniopterus schreibersii using immunocytochemical (ICC) staining at the light and electron microscopy level. Mammotropes were distributed throughout the gland, were polygonal in shape and during secretory activity contained numerous large secretory granules (350 - 800nm). Using double ICC labelling, prolactin and growth hormone were never co-localiszed and found in individual cells only. Plasma prolactin levels were successfully measured on a monthly basis using radioimmunoassay and monthly pituitary prolactin levels were quantified using morphometric analysis of immunogold ICC staining and densitometry with polyacrylamide gels. Seasonal changes in the ultrastructure of mammotropes, and pituitary and plasma prolactin concentrations in female Miniopterus schreibersii indicated that there was an increase in prolactin secretion during the second half of the period of delayed implantation and that prolactin secretion remained elevated during normal embryonic development and lactation. This suggests that prolactin may be part of the luteotropic and lactogenic complex, and that the hormone might be responsible for terminating the period of delayed implantation. The latter is supported by experiments, where exogenous prolactin initiated precocious implantation during early delayed implantation, and treatment with bromocryptine (which inhibits prolactin synthesis) retarded implantation. Activation of mammotropes to synthesise prolactin and an increase of plasma prolactin levels occurred shortly after the winter solstice (21 June), suggesting that increasing daylength may be the environmental cue, which terminates the period of delayed implantation in Miniopterus schreibersii.
214

Aspects of heterothermy in four species of afrotropical bats

Doty, Anna Catherine January 2012 (has links)
Torpor and hibernation, two distinct forms of heterothermy, are physiological responses employed by many endotherms to save energy during periods of cold, climatic unpredictability and food shortage. Heterothermy is characterized by varying body temperature and has been found to occur in various subtropical mammals. However, studies on thermoregulatory capabilities of South African Microchiroptera remain relatively scant. In this study, the capacity for use of heterothermy, the seasonal metabolic rates, and capacity for non-shivering thermogenesis were studied in four species of bats, namely Rhinolophus clivosus, Rhinolophus capensis, Miniopterus natalensis and Myotis tricolor. Animals were collected from a group of three mines in Sleepy Hollow Farm, 30km from Port Elizabeth, South Africa. All species demonstrated bouts of torpor in the winter while R. clivosus interestingly established a high propensity for torpor in the summer and normothermia in the winter. To my knowledge, this is the first study that has shown the down-regulation of metabolism and body temperature in summer and constant maintenance of normothermic body temperature in winter in a species of Microchiroptera. M. natalensis was thermolabile in both summer and winter and body temperatures closely tracked ambient temperatures. Mean ± SD normothermic body temperature measured of wild-caught R. clivosus and M. natalensis was 38.6 ± 1.7°C and 37.3 ± 2.2°C, respectively. Mean torpid body temperature measured of wild-caught R. clivosus, R. capensis and M. natalensis was 22.7 ± 3.3°C, 21.1 ± 3.2 °C, and 22.6 ± 3.1°C, respectively. Non-shivering thermogenesis was measured in R. clivosus and M. natalensis to determine the role of endogenous heat production in a volant mammal. The mean noradrenalineinduced thermogenesis ± SD in R. clivosus and M. natalensis was 2.6 ± 0.8 ml g-1 hr-1 and 2.7 ± 0.6 ml O2 g-1 hr-1, respectively. Both species demonstrated capacity for non-shivering thermogenesis, and this is the first study that has quantified the maximal response to noradrenaline in an Afrotropical Microchiropteran species. Physiology of Afrotropical bats is understudied and the extent to which torpor and/or hibernation is utilized amongst them remains relatively unknown. Heterothermy clearly plays a significant role in the energetic savings and balance of all four species in the study.
215

Ecological and Sociological Considerations of Wind Energy: A Multidisciplinary Study

Bicknell, Lucas J. January 2012 (has links)
Wind energy is quickly becoming a critical technology for providing Americans with renewable energy, and rapid construction of wind facilities may have impacts on both wildlife and human communities. Understanding both the social and ecological issues related to wind energy development could provide a framework for effectively meeting human energy needs while conserving species biodiversity. In this research I looked at two aspects of wind energy development: public attitudes toward wind energy development and wind facility impacts on local bat populations. These papers present aspects of wind energy development that have been the subject of increasing study. This preliminary research is intended to demonstrate the responsibility we have to making well-informed decisions as we continue to expand wind energy development. Additionally, I hope to generate interest in interdisciplinary study as a means to broaden the scope of research by making use of the diverse tools available within different disciplines.
216

Likvärdig utbildning för elever med hörselnedsättning i majoritetsskolor : En studie om extra anpassningar för en inkluderande undervisning i de lägre årskurserna

Forsman, Cajsa, Eriksson, Josefine January 2019 (has links)
I läroplanen för grundskolan står det skrivet att skolan är skyldig att anpassa undervisningen så att alla elever får hjälp att nå målen. Syftet med studien är att undersöka skolsituationen för elever med hörselnedsättning, samt vilka extra anpassningar som kan tillämpas för dessa elever. Genom kvalitativa metoder undersöker studien hur elever med hörselnedsättning kan inkluderas i den ordinarie undervisningen. Bain och Legers modell för faktorer som påverkar användning av hjälpmedel för individer med hörselnedsättning har agerat analysmodell i studien. Resultatet visar att omgivningen, lärarens profession och medvetenhet samt teknik bör anpassas för att elever med hörselnedsättning ska kunna delta i undervisningen på ett likvärdigt sätt. Som slutsats för studien framkommer det att det som är viktigast för att elever med hörselnedsättning ska få ta del av undervisningen på ett likvärdigt sätt som övriga elever så krävs det att läraren är medveten om hörselnedsättningar och har ett tydligt och välplanerat arbetssätt.
217

Bat Population Monitoring in National Parks of The Great Lakes Region and Evaluation of Bat Acoustic Analysis Software

Goodwin, Katy Rebecca January 2019 (has links)
North American bats face multiple threats, prompting an increase in bat research and conservation efforts in recent decades. Researchers often use acoustic monitoring, which entails recording bats? echolocation calls and subsequently identifying them to species, typically using automated software. Chapter 1 describes an acoustic monitoring program at eight U.S. national parks that aims to assess changes in bat populations over time. Data collected in 2016-2017 showed that activity levels of the little brown bat (Myotis lucifigus) decreased significantly while other species remained stable. Little brown bats have undergone similar population declines elsewhere due to the disease white-nose syndrome. Chapter 2 investigates whether different versions of bat call identification software are comparable to each other and how accurate they are. For the two software programs tested, agreement among versions was variable and species-dependent. Furthermore, newer versions were more conservative in assigning identifications, though not, on average, more accurate.
218

Evaluating Bat Roost Abundance: A Comparison of Drone-Acquired Thermal Imagery and Acoustic Estimates with Visual Observations

Jaffe, Karah 01 August 2022 (has links)
Roosts provide an opportunity to census philopatric populations of bats. Comparing the efficacy of traditional methods with novel methods can provide guidance on the use of new technologies in the field. This project aims to compare the count efficacy of external emergence methodologies, i.e., drone-acquired thermal imagery, acoustic estimates, and visual counts. Surveys were conducted ten nights at two emergence sites and synchronized to compare counts. Acoustic estimates could not be established as there was a weak prediction of the linear relationship between root-mean-square pressure and emergence count; therefore, this method was removed from the comparative analysis. A linear mixed-effects model and Bonferroni correction found a significant difference in visual and thermal methods at the eastern Tennessee site. Additionally, there was an overall median similarity of 92% from counts obtained from the compared methods. This study supports the validity of drone-acquired thermal imagery for external emergence counts.
219

East Tennessee Spatial and Temporal Species-Specific Bat Activity Patterns

Morelock, Seth 01 May 2023 (has links) (PDF)
Determining the activity among species-specific bat populations within specific habitat selections can help contribute to the conservation of Appalachian bat species. This study examines the differences in species-specific bat activity patterns between three ponds of variable sizes and a southeast-facing open field with a wooded edge. Four Song Meter SM4BAT FS bioacoustics detectors were used on a 15-acre property in Fall Branch, TN, with a wildlife acoustics detector being placed at three ponds and one field. There were three stages of data collection for this study which all took place during 2023. The first stage was during the spring (March 18th – May 18th), the second stage was during the summer (June 21st – August 27th), and the third stage was during the fall (September 26th – October 26th). Acoustic recordings were analyzed through SonoBat to classify them to species level using a recording call quality threshold of ≥ 95%. An identification likelihood of ≥ 90% yielded 36,308 calls assigned to a particular species/genus. The acoustic detectors detected eight bat species and the Myotis genus throughout the study. Species identified include Rafinesque's big-eared bat (Corynorhinus rafinesquii), big brown bat (Eptesicus fuscus), hoary bat (Lasiurus cinereus), silver-haired bat (Lasionycteris noctivagans), eastern red bat (Lasiurus borealis), evening bat (Nycticeius humeralis), tricolored bat (Pipistrellus subflavus), Mexican free-tailed bat (Tadarida brasiliensis), and species within the Myotis genus. Two chi-square analyses were performed through R to determine if there were significant spatial and temporal species-specific activity patterns between the four sites. Both chi-square analyses resulted in a p-value < 2.2e-16 indicating significant differences in species-specific activity levels between the four sites throughout spring, summer, and fall. This data can help species-specific conservation efforts by understanding bat species’ activity levels at particular habitat selections throughout the fall, summer, and spring seasons.
220

Understanding the Winter Habitats of Ohio’s Hibernating Bats

Johnson, Levi E. 10 September 2021 (has links)
No description available.

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