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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.
201

Eletro-síntese de novos poli(p-fenileno-vinileno)s e estudo de sua aplicação potencial em dispositivos opto-eletrônicos e narizes eletrônicos / Electro-synthesis of new poly (p-phenylene-vinylene) to study its potential application in opto-electronic devices and electronic noses

Yoshikawa, Eduardo Kunio Chinone 13 August 2004 (has links)
A presente tese de doutorado deu início a uma nova linha de pesquisa no grupo de Síntese de Polímeros Condutores do IQ-USP, que consiste nos estudos relacionados a sensores de gases para equipamentos do tipo narizes eletrônicos, confeccionados com polímeros condutores. Para isso, foram sintetizados eletroquimicamente sete polímeros da família dos poli(p-fenileno vinileno)s, dos quais cinco inéditos, substituídos por grupos receptores e doadores de elétrons.Todos os polímeros, incluindo seus precursores, foram caracterizados espectroscopicamente (RMN de 1H, IV e UV-Vis). Estudos de análises térmicas (TG e DSC) e de cromatografia por exclusão de tamanho (SEC) foram realizados com os polímeros que possuíam grupos alifáticos de cadeias longas, tendo sido um desses polímeros usado na confecção de dispositivos metal/polímero/metal, cujas medidas de corrente vs. tensão permitiram determinar a mobilidade dos portadores de carga. Sensores de gases foram feitos com os polímeros sintetizados, mostrando boa seletividade quando testados com vapores de uma série de solventes orgânicos polares e apolares. / In this thesis we describe the electrosynthesis of seven difterent poly(p-phenilenevinylene)s, PPVs, bearing long and short, electron donating and withdrawing side groups. These polymers are aimed for our recent interest in gas sensors based on conducting polymers and their application in electronic noses. Five out of the seven polymers are novel materials, hence never described before. The polymers were characterized spectroscopically. Those with long side chain were also submitted to thermal analyses and size exclusion chromatography. Electrical measurements (I x V) in metal/polymer/metal sandwich devices led to the determination of the charge carrier mobility of one of the polymers. Gas sensors, having thin films of the synthesized polymers as active layers, have shown good selectivity towards several organic solvent vapors and water as well.
202

Two- and Three-dimensional Face Recognition under Expression Variation

Mohammadzade, Narges Hoda 30 August 2012 (has links)
In this thesis, the expression variation problem in two-dimensional (2D) and three-dimensional (3D) face recognition is tackled. While discriminant analysis (DA) methods are effective solutions for recognizing expression-variant 2D face images, they are not directly applicable when only a single sample image per subject is available. This problem is addressed in this thesis by introducing expression subspaces which can be used for synthesizing new expression images from subjects with only one sample image. It is proposed that by augmenting a generic training set with the gallery and their synthesized new expression images, and then training DA methods using this new set, the face recognition performance can be significantly improved. An important advantage of the proposed method is its simplicity; the expression of an image is transformed simply by projecting it into another subspace. The above proposed solution can also be used in general pattern recognition applications. The above method can also be used in 3D face recognition where expression variation is a more serious issue. However, DA methods cannot be readily applied to 3D faces because of the lack of a proper alignment method for 3D faces. To solve this issue, a method is proposed for sampling the points of the face that correspond to the same facial features across all faces, denoted as the closest-normal points (CNPs). It is shown that the performance of the linear discriminant analysis (LDA) method, applied to such an aligned representation of 3D faces, is significantly better than the performance of the state-of-the-art methods which, rely on one-by-one registration of the probe faces to every gallery face. Furthermore, as an important finding, it is shown that the surface normal vectors of the face provide a higher level of discriminatory information rather than the coordinates of the points. In addition, the expression subspace approach is used for the recognition of 3D faces from single sample. By constructing expression subspaces from the surface normal vectors at the CNPs, the surface normal vectors of a 3D face with single sample can be synthesized under other expressions. As a result, by improving the estimation of the within-class scatter matrix using the synthesized samples, a significant improvement in the recognition performance is achieved.
203

Two- and Three-dimensional Face Recognition under Expression Variation

Mohammadzade, Narges Hoda 30 August 2012 (has links)
In this thesis, the expression variation problem in two-dimensional (2D) and three-dimensional (3D) face recognition is tackled. While discriminant analysis (DA) methods are effective solutions for recognizing expression-variant 2D face images, they are not directly applicable when only a single sample image per subject is available. This problem is addressed in this thesis by introducing expression subspaces which can be used for synthesizing new expression images from subjects with only one sample image. It is proposed that by augmenting a generic training set with the gallery and their synthesized new expression images, and then training DA methods using this new set, the face recognition performance can be significantly improved. An important advantage of the proposed method is its simplicity; the expression of an image is transformed simply by projecting it into another subspace. The above proposed solution can also be used in general pattern recognition applications. The above method can also be used in 3D face recognition where expression variation is a more serious issue. However, DA methods cannot be readily applied to 3D faces because of the lack of a proper alignment method for 3D faces. To solve this issue, a method is proposed for sampling the points of the face that correspond to the same facial features across all faces, denoted as the closest-normal points (CNPs). It is shown that the performance of the linear discriminant analysis (LDA) method, applied to such an aligned representation of 3D faces, is significantly better than the performance of the state-of-the-art methods which, rely on one-by-one registration of the probe faces to every gallery face. Furthermore, as an important finding, it is shown that the surface normal vectors of the face provide a higher level of discriminatory information rather than the coordinates of the points. In addition, the expression subspace approach is used for the recognition of 3D faces from single sample. By constructing expression subspaces from the surface normal vectors at the CNPs, the surface normal vectors of a 3D face with single sample can be synthesized under other expressions. As a result, by improving the estimation of the within-class scatter matrix using the synthesized samples, a significant improvement in the recognition performance is achieved.
204

Signal processing for biologically-inspired gradient source localization and DNA sequence analysis

Rosen, Gail L. 12 July 2006 (has links)
Biological signal processing can help us gain knowledge about biological complexity, as well as using this knowledge to engineer better systems. Three areas are identified as critical to understanding biology: 1) understanding DNA, 2) examining the overall biological function and 3) evaluating these systems in environmental (ie: turbulent) conditions. DNA is investigated for coding structure and redundancy, and a new tandem repeat region, an indicator of a neurodegenerative disease, is discovered. The linear algebraic framework can be used for further analysis and techniques. The work illustrates how signal processing is a tool to reverse engineer biological systems, and how our better understanding of biology can improve engineering designs. Then, the way a single-cell mobilizes in response to a chemical gradient, known as chemotaxis, is examined. Inspiration from receptor clustering in chemotaxis combined with a Hebbian learning method is shown to improve a gradient-source (chemical/thermal) localization algorithm. The algorithm is implemented, and its performance is evaluated in diffusive and turbulent environments. We then show that sensor cross-correlation can be used in solving chemical localization in difficult turbulent scenarios. This leads into future techniques which can be designed for gradient source tracking. These techniques pave the way for use of biologically-inspired sensor networks in chemical localization.
205

Avaliação tecnológica e clínica de protetores nasais empregados na ventilação não invasiva de recém-nascidos / Clinical and technological assessment of nasal protectors employed in non-invasive ventilation of newborns

Camillo, Débora de Fátima 26 August 2016 (has links)
A lesão nasal decorrente do uso da ventilação não invasiva (VNI) é um evento adverso cada vez mais comum nas unidades de terapia intensiva neonatais (UTIN) e apresenta consequências a curto e longo prazo. Esta lesão pode resultar em sequelas tanto de ordem estética quanto funcional, limitar o uso da VNI em RN que necessita desse suporte ventilatório, causar desconforto e septicemia; podendo aumentar, desta forma, o tempo de internamento na UTIN. Esta pesquisa tem por objetivo avaliar tecnológica e clinicamente os protetores nasais empregados na VNI de RN internados na UTIN. A metodologia consistiu primeiramente em levantar as possíveis causas da lesão nasal e avaliar os fatores de risco associados ao seu desenvolvimento. Em seguida, foi realizado um ensaio clínico randomizado para comparar os efeitos de três tipos de proteção nasal e das prongas novas e esterilizadas sobre a gravidade da lesão nasal. E por fim, foi realizada a caracterização térmica e estrutural dos protetores nasais após serem envelhecidas com temperatura e umidade no interior da incubadora neonatal. As principais causas da lesão foram relacionadas às características do material, a problemas no equipamento, a fatores assistenciais, neonatais e profissionais. Neste estudo, foram constatados como fatores de risco: a idade gestacional, a massa ao nascer, o tempo total de permanência na VNI, a reutilização deste suporte, o tempo da primeira utilização e da reutilização da VNI, bem como o tempo de internação na UTIN. Não foram observadas diferenças significativas na gravidade da lesão quando comparadas as três proteções estudadas, nem quando utilizadas prongas novas e esterilizadas. Quanto à análise dos materiais, foi constatado que a exposição à temperatura e à umidade alterou a percentagem de cristalinidade e a rugosidade das proteções nasais estudadas. / The nasal injury resulting from the use of non-invasive ventilation (NIV) is an adverse event increasingly common in the newborn intensive care unit (NICU) and shows the short and long term consequences. This lesion can result both aesthetic and functional sequelae, limit the use of NIV in newborns who need this ventilatory support, cause discomfort and septicemia, may thereby increase the length of stay in NICU. This research aims to evaluate technological and clinically nasal protectors used with NIV of newborns admitted to the NICU. The methodology consisted primarily in raising the possible causes of nasal injury and assess the risk factors associated with its development. Then, it was conducted a randomized clinical trial to compare the effects of three kind of nasal protector and new and sterilized prongs on the severity of nasal lesions. And finally, it was performed the thermal and structural characterization of nasal protection after being aged with temperature and humidity inside the neonatal incubator. The main causes of injury were related to characteristics of the material, equipment problems, assistive, neonatal and professional factors. In this study, it was found as risk factors: gestational age, weight at birth, the total time stay in the NIV, the reuse of this support, the time of first use and reuse of NIV and the length of stay in the NICU. They were not observed significant differences in lesion severity when compared the three protectors studied, nor when used new and sterilized prongs. The materials analysis indicated that exposure to temperature and humidity changed the percentage of crystallinity and the roughness of the nasal protections studied.
206

Avaliação tecnológica e clínica de protetores nasais empregados na ventilação não invasiva de recém-nascidos / Clinical and technological assessment of nasal protectors employed in non-invasive ventilation of newborns

Camillo, Débora de Fátima 26 August 2016 (has links)
A lesão nasal decorrente do uso da ventilação não invasiva (VNI) é um evento adverso cada vez mais comum nas unidades de terapia intensiva neonatais (UTIN) e apresenta consequências a curto e longo prazo. Esta lesão pode resultar em sequelas tanto de ordem estética quanto funcional, limitar o uso da VNI em RN que necessita desse suporte ventilatório, causar desconforto e septicemia; podendo aumentar, desta forma, o tempo de internamento na UTIN. Esta pesquisa tem por objetivo avaliar tecnológica e clinicamente os protetores nasais empregados na VNI de RN internados na UTIN. A metodologia consistiu primeiramente em levantar as possíveis causas da lesão nasal e avaliar os fatores de risco associados ao seu desenvolvimento. Em seguida, foi realizado um ensaio clínico randomizado para comparar os efeitos de três tipos de proteção nasal e das prongas novas e esterilizadas sobre a gravidade da lesão nasal. E por fim, foi realizada a caracterização térmica e estrutural dos protetores nasais após serem envelhecidas com temperatura e umidade no interior da incubadora neonatal. As principais causas da lesão foram relacionadas às características do material, a problemas no equipamento, a fatores assistenciais, neonatais e profissionais. Neste estudo, foram constatados como fatores de risco: a idade gestacional, a massa ao nascer, o tempo total de permanência na VNI, a reutilização deste suporte, o tempo da primeira utilização e da reutilização da VNI, bem como o tempo de internação na UTIN. Não foram observadas diferenças significativas na gravidade da lesão quando comparadas as três proteções estudadas, nem quando utilizadas prongas novas e esterilizadas. Quanto à análise dos materiais, foi constatado que a exposição à temperatura e à umidade alterou a percentagem de cristalinidade e a rugosidade das proteções nasais estudadas. / The nasal injury resulting from the use of non-invasive ventilation (NIV) is an adverse event increasingly common in the newborn intensive care unit (NICU) and shows the short and long term consequences. This lesion can result both aesthetic and functional sequelae, limit the use of NIV in newborns who need this ventilatory support, cause discomfort and septicemia, may thereby increase the length of stay in NICU. This research aims to evaluate technological and clinically nasal protectors used with NIV of newborns admitted to the NICU. The methodology consisted primarily in raising the possible causes of nasal injury and assess the risk factors associated with its development. Then, it was conducted a randomized clinical trial to compare the effects of three kind of nasal protector and new and sterilized prongs on the severity of nasal lesions. And finally, it was performed the thermal and structural characterization of nasal protection after being aged with temperature and humidity inside the neonatal incubator. The main causes of injury were related to characteristics of the material, equipment problems, assistive, neonatal and professional factors. In this study, it was found as risk factors: gestational age, weight at birth, the total time stay in the NIV, the reuse of this support, the time of first use and reuse of NIV and the length of stay in the NICU. They were not observed significant differences in lesion severity when compared the three protectors studied, nor when used new and sterilized prongs. The materials analysis indicated that exposure to temperature and humidity changed the percentage of crystallinity and the roughness of the nasal protections studied.
207

Eletro-síntese de novos poli(p-fenileno-vinileno)s e estudo de sua aplicação potencial em dispositivos opto-eletrônicos e narizes eletrônicos / Electro-synthesis of new poly (p-phenylene-vinylene) to study its potential application in opto-electronic devices and electronic noses

Eduardo Kunio Chinone Yoshikawa 13 August 2004 (has links)
A presente tese de doutorado deu início a uma nova linha de pesquisa no grupo de Síntese de Polímeros Condutores do IQ-USP, que consiste nos estudos relacionados a sensores de gases para equipamentos do tipo narizes eletrônicos, confeccionados com polímeros condutores. Para isso, foram sintetizados eletroquimicamente sete polímeros da família dos poli(p-fenileno vinileno)s, dos quais cinco inéditos, substituídos por grupos receptores e doadores de elétrons.Todos os polímeros, incluindo seus precursores, foram caracterizados espectroscopicamente (RMN de 1H, IV e UV-Vis). Estudos de análises térmicas (TG e DSC) e de cromatografia por exclusão de tamanho (SEC) foram realizados com os polímeros que possuíam grupos alifáticos de cadeias longas, tendo sido um desses polímeros usado na confecção de dispositivos metal/polímero/metal, cujas medidas de corrente vs. tensão permitiram determinar a mobilidade dos portadores de carga. Sensores de gases foram feitos com os polímeros sintetizados, mostrando boa seletividade quando testados com vapores de uma série de solventes orgânicos polares e apolares. / In this thesis we describe the electrosynthesis of seven difterent poly(p-phenilenevinylene)s, PPVs, bearing long and short, electron donating and withdrawing side groups. These polymers are aimed for our recent interest in gas sensors based on conducting polymers and their application in electronic noses. Five out of the seven polymers are novel materials, hence never described before. The polymers were characterized spectroscopically. Those with long side chain were also submitted to thermal analyses and size exclusion chromatography. Electrical measurements (I x V) in metal/polymer/metal sandwich devices led to the determination of the charge carrier mobility of one of the polymers. Gas sensors, having thin films of the synthesized polymers as active layers, have shown good selectivity towards several organic solvent vapors and water as well.
208

Development of a Sensor System for Rapid Detection of Volatile Organic Compounds in Biomedical Applications

Paula Andrea Angarita (11806427) 20 December 2021 (has links)
<p>Volatile organic compounds (VOCs) are endogenous byproducts of metabolic pathways that can be altered by a disease or condition, leading to an associated and unique VOC profile or signature. Current methodologies for VOC detection include canines, gas chromatography-mass spectrometry (GC-MS), and electronic nose (eNose). Some of the challenges for canines and GC-MS are cost-effectiveness, extensive training, expensive instrumentation. On the other hand, a significant downfall of the eNose is low selectivity. This thesis proposes to design a breathalyzer using chemiresistive gas sensors that detects VOCs from human breath, and subsequently create an interface to process and deliver the results via Bluetooth Low Energy (BLE). Breath samples were collected from patients with hypoglycemia, COVID-19, and healthy controls for both. Samples were processed, analyzed using GC-MS and probed through statistical analysis. A panel of 6 VOC biomarkers distinguished between hypoglycemia (HYPO) and Normal samples with a training AUC of 0.98 and a testing AUC of 0.93. For COVID-19, a panel of 3 VOC biomarkers distinguished between COVID-19 positive symptomatic (COVID-19) and healthy Control samples with a training area under the curve (AUC) of receiver operating characteristic (ROC) of 1.0 and cross-validation (CV) AUC of 0.99. The model was validated with COVID-19 Recovery samples. The discovery of these biomarkers enables the development of selective gas sensors to detect the VOCs. </p><p><br></p><p>Polyethylenimine-ether functionalized gold nanoparticle (PEI-EGNP) gas sensors were designed and fabricated in the lab and metal oxide (MOX) semiconductor gas sensors were obtained from Nanoz (Chip 1: SnO<sub>2</sub> and Chip 2: WO<sub>3</sub>). These sensors were tested at different relative humidity (RH) levels, and VOC concentrations. Contact angle which measures hydrophobicity, was 84° and the thickness of the PEI-EGNP coating was 11 µ m. The PEI-EGNP sensor response at RH 85% had a signal 10x higher than at RH 0%. Optimization of the MOX sensor was performed by changing the heater voltage and concentration of VOCs. At RH 85% and heater voltage of 2500 mV, the performance of the sensors increased. Chip 2 had higher sensitivity towards VOCs especially for one of the VOC biomarkers identified for COVID-19. PCA distinguished VOC biomarkers of HYPO, COVID-19, and healthy human breath using the Nanoz. A sensor interface was created to integrate the PEI-EGNP sensors with the printed circuit board (PCB) and Bluno Nano to perform machine learning. The sensor interface can currently process and make decisions from the data whether the breath is HYPO (-) or Normal (+). This data is then sent via BLE to the Hypo Alert app to display the decision.</p>
209

Microbiome cutané et maladie fongique émergente du syndrome du museau blanc chez les chauves-souris d’Amérique du Nord

Lemieux-Labonté, Virginie 09 1900 (has links)
Le syndrome du museau blanc (SMB), causé par le champignon Pseudogymnoascus destructans (Pd), a mis en péril les populations de chauves-souris hibernantes en Amérique du Nord. Certaines espèces sont hautement vulnérables à la maladie alors que d’autres espèces semblent être résistantes ou tolérantes à l’infection. Plusieurs facteurs physiologiques et environnementaux peuvent expliquer ces différences. Or avant 2015, peu d’études avaient porté sur le microbiome de la peau en relation avec cette maladie. La présente thèse vise à caractériser le microbiome cutané de chiroptères affectés par le SMB afin d’identifier les facteurs de vulnérabilité ou de résistance à la maladie. L’objectif principal est de déterminer comment le microbiome est affecté par la maladie ainsi que de déterminer si celui-ci à un rôle dans la protection face à l’infection fongique. Au Chapitre 1, nous avons tout d’abord exploré et comparé le microbiote cutané de petites chauves-souris brunes (Myotis lucifugus) non affectées par le SMB avec celui de chauves-souris survivantes au SMB pour tester l’hypothèse selon laquelle le microbiote cutané est modifié par la maladie. Nos résultats montrent que le site d’hibernation influence fortement la composition et la diversité du microbiote cutané. Les sites d’hibernations Pd positifs et négatifs diffèrent significativement en termes de diversité, ainsi qu’en termes de composition du microbiote. La diversité est réduite au sein du microbiote des chauves-souris survivantes au SMB et enrichi en taxons tels que Janthinobacterium, Micrococcaceae, Pseudomonas, Ralstonia et Rhodococcus. Certains de ces taxons sont reconnus pour leur potentiel antifongique et des souches spécifiques de Rhodococcus et de Pseudomonas peuvent inhiber la croissance de Pd. Nos résultats sont cohérents avec l’hypothèse selon laquelle l’infection par Pd modifie le microbiote cutané des chauves-souris survivantes et suggèrent que le microbiote peut jouer un rôle de protection face au SMB. Au Chapitre 2, nous avons étudié le microbiote d’une espèce résistante au champignon Pd en milieu contrôlé avant et après infection afin d’établir la réponse potentielle à la maladie. L’espèce étudiée est la grande chauve-souris brune (Eptesicus fuscus) dont le microbiote cutané pourrait jouer un rôle de protection contre l’infection. Nos résultats montrent que la diversité du microbiote de la grande chauve-souris brune inoculée avec Pd est plus variable dans le temps, tandis que la diversité du microbiote des chauves-souris du groupe contrôle demeure stable. Parmi les taxons les plus abondants, Pseudomonas et Rhodococcus, deux taxons connus pour leur potentiel antifongique contre Pd et d’autres champignons, sont restés stables durant l’expérience. Ainsi, bien que l’inoculation par le champignon Pd ait déstabilisé le microbiote cutané, les bactéries aux propriétés antifongiques n’ont pas été affectées. Cette étude est la première à démontrer le potentiel du microbiote cutané d’une espèce de chauves-souris pour la résistance au SMB. Au Chapitre 3, le microbiome cutané de la petite chauve-souris brune a été évalué en milieu naturel dans le contexte du SMB, à l’aide de la métagénomique, une approche haute résolution pour observer le potentiel fonctionnel du microbiome (métagénome fonctionnel). Nos résultats ont permis d’établir que le temps depuis l’infection a un effet significatif sur le métagénome fonctionnel. En effet, les chauves-souris dans la première année suivant l’infection ont un métagénome fonctionnel perturbé qui subit une perte de diversité fonctionnelle importante. Toutefois, le métagénome fonctionnel revient à une structure et composition similaire d’avant infection après 10 ans. Certaines fonctions détectées suite à l’infection sont associées à des gènes reliés au transport et à l’assimilation de métaux, des facteurs limitants pour la croissance du champignon. Ces gènes pourraient donc avoir un rôle à jouer dans la résistance ou la vulnérabilité à la maladie. Globalement, l’étude du métagénome chez la petite chauve-souris brune indique une vulnérabilité du métagénome fonctionnel au champignon, mais que celui-ci semble se rétablir après 10 ans. Une telle réponse pourrait avoir un impact sur la résilience de M. lucifugus. Cette thèse a permis d’acquérir des connaissances fondamentales sur le microbiome cutané des chauves-souris en hibernation pour mieux comprendre les communautés microbiennes de la peau dans le contexte du SMB. Le microbiome pourrait en effet jouer un rôle dans la vulnérabilité et la résistance des chauves-souris à la maladie, et il est essentiel d’adapter notre façon d’aborder la protection de ces espèces et de leur microbiome. Nous souhaitons que les travaux de cette thèse permettent de sensibiliser les acteurs de la conservation à l’existence et à l’importance potentielle du microbiome pour la santé de son hôte. Cette thèse fait également état de l’avancement des méthodes d’analyses qui permettront d’être de plus en plus précis et d’appliquer les connaissances du microbiome en biologie de la conservation. / White-nose syndrome (WNS) caused by the fungus Pseudogymnoascus destructans (Pd) has put hibernating bat populations at risk in North America. Some species are highly vulnerable to the disease while other species appear to be resistant or tolerant. Several physiological and environmental factors can explain these differences. However, before 2015, few studies have focused on the skin microbiome in relation to this disease. The present thesis aims to characterize the cutaneous microbiome of bats affected by WNS in order to identify the factors of vulnerability or resistance to the disease. The main objective is to determine how the microbiome can protect against the Pd fungus, or conversely how the microbiome is altered by the fungal infection. In Chapter 1, we first explored and compared the skin microbiota of little brown bats (Myotis lucifugus) unaffected by WNS with that of WNS survivors to test the hypothesis that the skin microbiota is modified by the disease. Our results show that the hibernation site strongly influences the composition and diversity of the skin microbiota. The Pd positive and negative sites differ significantly in terms of diversity, as well as in terms of the composition of the microbiota. Diversity is reduced within the microbiota of bats surviving WNS and enriched in taxa such as Janthinobacterium, Micrococcaceae, Pseudomonas, Ralstonia, and Rhodococcus. Some of these taxa are recognized for their antifungal potential and specific strains of Rhodococcus and Pseudomonas may inhibit the growth of Pd. Our results are consistent with the hypothesis that Pd infection modifies the skin microbiota of surviving bats and suggest that the microbiota may play a protective role against WNS. In Chapter 2, we studied in a controlled environment the microbiota of a species that exhibits evidence of resistance with mild WNS symptoms, before and after infection, to establish the potential response to the disease. The species studied is the big brown bat (Eptesicus fuscus), whose skin microbiota could play a protective role against infection. Our results show that the diversity of the microbiota of big brown bats inoculated with Pd is more variable over time, while the diversity of the microbiota of the control bats remains stable. Among the most abundant taxa, Pseudomonas and Rhodococcus, two taxa known for their antifungal potential against Pd and other fungi, remained stable during the experiment. Thus, although inoculation with the Pd fungus destabilized the skin microbiota, bacteria with antifungal properties were not affected. This study is the first to demonstrate the potential of the skin microbiota of a bat species for resistance to WNS. In Chapter 3, the skin microbiome of the little brown bat was evaluated in the natural environment in the context of WNS, using metagenomics, a higher-resolution approach to observe the functional potential of the microbiome (functional metagenome). Our results established that the time since infection has a significant effect on the functional metagenome. Indeed, bats in the first year after infection have a disrupted functional metagenome that undergoes a significant loss of functional diversity. However, the functional metagenome returns to a similar structure and composition to that observed before infection after 10 years. Certain functions detected following infection are associated with genes linked to the transport and assimilation of metals, known limiting factors for the growth of the fungus. These genes could therefore have a role to play in resistance or vulnerability to the disease. Overall, this metagenomics study indicates functional metagenome vulnerability to the fungus, although the original functional metagenome is reestablished after 10 years. Such diversified response could impact M. lucifugus resilence. This thesis provides fundamental knowledge on the skin microbiome of hibernating bats to better understand the microbial communities of the skin in the context of WNS. The microbiome could indeed play a role in the vulnerability and resistance of bats to disease and it is essential to adapt our way of approaching the protection of these species and their microbiomes. We hope that the results of this thesis will raise awareness among conservation stakeholders about the existence and potential importance of the microbiome for the health of its host. This thesis also reports on the advancement of analytical methods that will make it possible to be more and more precise and to apply knowledge of the microbiome in conservation biology.
210

Dálniční most přes široké údolí / Highway bridge over wide wally

Mertová, Eliška January 2017 (has links)
The aim of this diploma thesis was the design of three possible variants, how to span the wide and deep valley with a bridge. After an evaluation, situation of the highway on the only wide load-bearing structure which is constituted by a box girder with transverse cantilevers supported by prefabricated bar braces, was chosen as an optimal solving. The load- bearing structure made of post- tensioned concrete is going to be incrementally launched and be supported by one-column pillars along an axis of the motorway. The work is composed of a detailed design of this preferred variant, which is processed according to the ultimate and serviceability limit state including the construction stage analysis of the bridge by the construction technology by an incremental launching method.

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