Thesis (M.S.)--Mississippi State University. Department of Biological Sciences. / Title from title screen. Includes bibliographical references.

Diss. Univ. Freiburg im Breisgau, 2007.

Thesis (Ph.D)--Industrial and Systems Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Earl Barnes; Committee Member: Arkadi Nemirovski; Committee Member: Faiz Al-Khayyal; Committee Member: Guillermo H. Goldsztein; Committee Member: Joel Sokol. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 155-166).

Οι ηλεκτρικά μικρές κεραίες χαρακτηρίζονται από εμπεδήσεις με μεγάλες αντιδράσεις και μικρή αντίσταση ακτινοβολίας. Αυτές οι αντιδράσεις λειτουργούν ως αποθήκη της ενέργειας που δίνεται στην κεραία μην επιτρέποντας της να ακτινοβολεί. Η προσαρμογή αυτών των εμπεδήσεων σε μια συγκεκριμένη τιμή αντίστασης (πχ 50 Ω) είναι πραγματική πρόκληση. Σε αυτή την εργασία θα εξετάσουμε τη δυνατότητα χρησιμοποίησης ενεργών κυκλωμάτων αρνητικής αντίστασης ώστε να «ακυρώσουμε» σε μια μεγάλη περιοχή συχνοτήτων τη χωρητική- επαγωγική συμπεριφορά μιας κεραίας, καθιστώντας έτσι το έργο της προσαρμογής πιο εύκολο. Στο πρώτο κεφάλαιο εξετάζουμε εισαγωγικές έννοιες των κεραιών και της προσαρμογής. Στο δεύτερο ασχολούμαστε θεωρητικά με κυκλώματα που παράγουν στην είσοδο τους μια αρνητική εμπέδηση. Στο τρίτο και στο τέταρτο κεφάλαιο εφαρμόζουμε την παραπάνω λογική σε ένα μονόπολο και μια patch κεραία αντίστοιχα. / Electrically small antennas present impedances characterized by large reactance and small radiation resistance. These reactances act to store much of the energy input to the antenna instead of allowing it to radiate. Matching these impedances to a 50-Ohm source is a real challenge. In this project we will consider the use of active negative resistance circuits in order to cancel out over o broadband the capacitive-inductive behavior of an antenna, making the task of matching easier. In the first chapter we consider introductory concepts of antennas and matching. In the second chapter we theoretically deal with circuits that produce a negative impedance at their input. In the third and fourth chapter we apply the previous concepts to a monopole and a patch antenna respectively.

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Made available in DSpace on 2015-03-03T11:52:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-07Bitstream added on 2015-03-03T12:07:10Z : No. of bitstreams: 1 000807003.pdf: 1969028 bytes, checksum: ffdf99374d166fada9ca950a025cb45d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Brasil lidera o ranking de maior exportador de carne bovina no mundo desde 2008. Garantir a segurança microbiológica desses alimentos tem sido um dos principais focos da indústria processadora de carnes. A aplicação de análises nas diversas etapas do processo industrial tem sido vital para implantar e manter programas de autocontrole como o APPCC. Entre as enfermidades mais frequentes causadas pela ingestão de alimentos contaminados, especialmente os de origem animal, destacam-se as salmoneloses, sendo que sua transmissão se dá primariamente pela via fecal oral. Diante disso, esse trabalho teve como objetivo pesquisar a presença de Salmonella spp. em amostras de conteúdo ruminal coletadas durante o abate de bovinos em uma planta frigorífica localizada na região metropolitana de Curitiba - PR. Duzentos e dois animais distribuídos em oito lotes foram avaliados entre os meses de agosto a dezembro de 2013. Ao final do experimento, 37,5% dos lotes mostraram-se positivos para o agente sendo que 2,97% (6/202) das amostras de conteúdo ruminal isolaram o micro-organismo. A totalidade dos animais positivos recebia como alimento apenas pasto de azevém e aveia. Não foi observada a influência de fatores como o estresse do transporte ou temperatura ambiental sobre o isolamento do patógeno. Entretanto a detecção do mesmo sorovar, Salmonella Schwarzengrund na totalidade dos isolamentos nos permite levantar a hipótese de que a contaminação dos animais tenha se dado na própria indústria, a partir das estruturas físicas, responsáveis por conter os bovinos ou conduzi-los ao box de insensibilização / Brazil leads the world ranking of bovine meat exportation since 2008. To ensure the microbiological safety of these food products has been one of the primary focuses of the meat processing industry. The application of analyses on diverse stages of the industrial process has been vital for deploy and keeping of self-control programs like APPCC. Beyond the most frequent diseases caused by the ingestion of contaminated food, specially animal origin ones, the salmonellosis stand out being transmitted primarily via fecal-oral route. In light of this, the work had the objective to research the presence of Salmonella spp. in rumen fluid samples collected during cattle slaughter at a slaughtering plant localized in Curitiba’s metropolitan area. Two hundred animals distributed over eight lots was evaluated between august and december, 2013. At the end of the experiment, 37.5% of the lots were positive for the agent of which 2.97% (6/202) of samples of rumen contents isolated the micro-organism.The total of the positive animals had been feed with ryegrass pastures and oat. Not the influence of factors like transportation stress or environment temperature over pathogen isolation was observed. However, the detection of the same serovar, Salmonella Schwarzengrund on overall insulation allow us to raise the hypothesis that all animal contamination have been given inside the industry itself, from the infrastructure responsible of holding the cattle or conducting it to the stunning box

Changes in the metabolic state of the brain can occur, for example, as a result of neuronal activity or in pathologies such as cancer. In these cases, an altered energy demand can lead to changes in neurochemical concentrations detectable using proton magnetic resonance spectroscopy (¹H-MRS). This thesis explores in vivo ¹H-MRS methods for detection of such changes in the healthy and diseased brain. Specifically, this thesis aims to develop methods with semi-LASER localisation, thereby minimising the negative effects of chemical shift displacement and field inhomogeneity on spectral acquisition. Firstly, a Hadamard-encoded semi-LASER method for simultaneous measurement from two regions was developed at 7 T. Slice profiles, with low chemical shift displacement and small amounts of signal overlap, were revealed in phantom and in vivo. This was then implemented in a study of neurochemical change during positive and negative blood oxygen level-dependent (BOLD) responses. Negative BOLD responses are thought to reflect regions of neuronal suppression. A small decrease in ascorbate, as well as the T2*-induced linebroadening of several spectra, were observed in these regions. Furthermore, increases in glutamate and lactate were detected in positive BOLD regions. These findings suggested that negative BOLD may not be generated by an increase in local GABA concentration. Secondly, an optimised semi-LASER sequence (TE = 110 ms) at 3 T was shown to improve localisation of the oncometabolite 2-hydroxyglutarate (2-HG) - a product of IDH-mutation found in the majority of gliomas. This resulted in improved detection of 2-HG in patients compared to an existing technique. The method was also compared to 7 T, where benefits of an increased spectral resolution resulted in significantly better detection of 2-HG along with associated metabolites. This thesis highlights the importance of robust localisation for performing sensitive in vivo ¹H-MRS neurochemical measurement in the human brain.

Les cancers agressifs se caractérisent par un métabolisme glycolytique exacerbé avec surexpression de protéines assurant le contrôle du pH intracellulaire par l’export efficace des déchets métaboliques acides (par CAIX, CAXII, MCT1 et MCT4 entre autres). Les cancers du sein dit "triple négatif" (sans expression des récepteurs à l'estrogène, progestérone et Her-2) présentent une consommation augmentée de glucose et un plus mauvais pronostic en comparaison avec les autres cancers du sein. L'analyse immunohistochimique de l'expression des protéines glycolytiques d'une cohorte de 159 patientes TNEG a montré que MCT4 était prédictif de la survenue de métastases et de décès. Le ciblage in vitro de MCT4 par la technique des Zinc Finger Nucléases (ZFN) a eu un effet anti-prolifératif. L'efficacité était toutefois maximale lors du ciblage combiné de MCT1 (inhibiteur pharmacologique), MCT4 et de la respiration mitochondriale par la phenformine dans la lignée de cancer TNEG Hs578t. Cette étude montre donc que le ciblage des protéines glycolytiques pourrait être une piste intéressante dans le traitement des cancers du sein TNEG. Un autre travail a permis d'exploiter le ciblage des protéines glycolytiques, notamment CAIX et CAXII, pour augmenter in vitro et in vivo la radiosensibilité de lignées de cancer colorectal tout en démontrant un mécanisme original de radiosensibilisation, via l'acidification intracellulaire. Enfin, nous avons mis en évidence l'importance de l'hypoxamiR miR210 dans la radiorésistance de lignées de cancer du poumon, avec une radiorésistance semblant dépasser l'effet oxygène. / Agressive cancers often harbor an exacerbated glycolytic metabolism with overexpression of proteins that maintain intracellular pH by extruding metabolic acid waste (via CAIX, CAXII, MCT1 and MCT4 among others). The "triple-negative" breast cancers (with no expression of estrogen, progesteron and Her-2 receptors) have an increased consumption of glucose and worse prognosis in comparison with other breast cancers. Immunohistochemical analysis of glycolytic proteins among 159 patients with TNEG breast cancer, showed that MCT4 was predictive for metastasis and death occurence. In vitro targeting of MCT4 by Zinc Finger Nuclease (ZFN) technique demonstrated an anti-proliferative effect. However, the maximal anti-proliferative effect was observed with the combination of MCT4/MCT1 (by pharmacological inhibition) and mitochondrial respiration by phenformine in the Hs578t TNEG cell line. This study demonstrated that targeting glycolytic protein could have a therapeutic effect in TNEG breast cancers. Another study also use targeting of glycolytic protein such as CAIX and CAXII to increase in vitro and in vivo radiosensitivity of colorectal cell lines while demonstrating an original mechanism of radiosensitization by increasing intracellular acidosis. Finally we demonstrated that the hypoxamiR miR210 was involved in the radioresistance of lung cancer cell line with a stronger impact than the oxygen effect.

Resumo: A ruptura do ligamento cruzado cranial é uma das causas mais comuns de claudicação do membro pélvico de cães. A radiografia e a ultrassonografia são métodos de diagnóstico já utilizados na rotina clínica de pequenos animais, a tomografia computadorizada é uma nova modalidade de imagem e sua utilização para avaliar a articulação do joelho de cães foi pouco estudada. O presente trabalho teve por objetivo avaliar a contribuição do contraste negativo na artrografia tomográfica do joelho normal de cães, para visibilizar as estruturas intra-articulares e padronizar o uso desse contraste na articulação. Foram utilizados 24 membros pélvicos de cães de raças variadas, selecionados pela ausência de histórico de doença articular prévia do joelho e por apresentarem exames radiográficos, ultrassonográficos e macroscópicos normais. O experimento foi delineado em dois grupos, sendo o grupo I animais com peso até 20 kg e grupo II acima de 20 kg. Foram feitos cortes tomográficos com o membro flexionado e estendido. Foi possível visibilizar pela imagem tomográfica, em todas as articulações, as seguintes estruturas: ligamento cruzado cranial e caudal, meniscos medial e lateral, ligamento patelar, ligamentos colaterais e cápsula articular. A quantidade média de ar utilizada para a distensão da cápsula articular foi de 49 ml para o grupo I e de 81 ml para o grupo II. Utillizou-se um tubo de látex na porção distal a articulação do joelho para reduzir o escape de ar pelo tendão extensor digital profundo, que possui comunicação intra-articular. O contraste negativo se mostrou uma alternativa eficaz para auxiliar a avaliação das estruturas anatômicas do joelho na artrografia tomográfica de forma segura e com baixo custo. / Abstract: The cranial cruciate ligament rupture is one of the most common causes of canine hindlimb lameness. The radiographic and ultrasonographic are methods of diagnosis used in small animal clinics, computed tomography is a new imaging exam and had been still little studied. This study aimed to evoluate the contribution of negative in computed tomography arthrography of the normal stifle of dogs for the visualization of intra-joint structures and standardize the use of contrast in the joint. There were used 24 pelvic limbs from dogs of various breeds, selected based on their history of absence of previous stifle joint disease and normal radiographic, ultrasonographic and macroscopic exams. The experiment was designed in two groups, group I animals weighing up to 20 kg and group II above 20 kg. Tomographic sections were done with the limb flexed and extended. Tomographic image allowed the visualization in all joints of the following structures: cranial and caudal cruciate ligament, medial and lateral menisci, patellar ligament, medial and lateral collateral ligament and joint capsule. The middle air quantity used for the joint capsule distension was 49 ml for group I and 81 ml for group II. A latex tube was used on the distal portion of the stifle to reduce air escaping through the long digital extensor tendon, which has intra-joint communication. Thus, the negative contrast (air) showed to be an effective alternative in the evaluation of the stifle anatomical structures by using tomography arthrography safely and at a low cost. / Orientador: Maria Jaqueline Mamprim / Coorientador: Luiz Carlos Vulcano / Banca: Sheila Canevese Rahal / Banca: Franklin de Almeida Sterman / Mestre