Tesi: "LTB" – Grafiati

1

Green, Elizabeth Allison. "The development and use of antigen-antibody-LTB (Ag-MAb-LTB) complexes as immunogens". Thesis, University of St Andrews, 1995. http://hdl.handle.net/10023/13984.

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In the course of this work a novel strategy has been developed for linking the adjuvant Escherichia coli heat-labile enterotoxin subunit B (LTB) to Simian Immunodeficiency Virus (SIV) proteins via an antibody bridge and the systemic and mucosal immunogenicity of such SIV-MAb-LTB complexes have been investigated. A short peptide tag, termed Pk, was joined to the 3'-end of the gene coding for LTB and expression studies revealed that the gene product, LTB-Pk, could be efficiently synthesised and secreted from non-pathogenic Vibrio sp.60. Analysis of the functional properties of LTB-Pk demonstrated that LTB-Pk , like native LTB, was a heat-labile oligomer, that could bind to the glycolipid GM1-ganglioside and was immunogenic in vivo. In attempts to purify LTB-Pk for immunisation studies, both hydrophobic and ion-exchange chromatography schedules were analysed, the latter procedure being more efficient. Strategies were developed for joining LTB-Pk to one arm of an anti-Pk MAb, (MAb SV5-P- k) and Pk-linked SIV proteins to the other arm, and such SFV-MAb-LTB complexes bound to GM1 -ganglioside in vitro. Systemic immunisation studies suggested that SIV-MAb-LTB complexes, using recombinant p17 as the target antigen, promoted both humoral and cell- mediated immunity to the recombinant p17. In addition, it was later shown that conjugation of LTB-Pk to recombinant SIV proteins via an antibody bridge, resulted in a more efficent presentation of the recombinant SIV protein to the immune system, than co-administration of LTB-Pk with the recombinant SIV protein. However, intranasal administration of p17-MAb-LTB complexes did not induce immunity to recombinant p17. Subsequently it was shown that the recombinant p17 was highly susceptible to mucosal degradation, suggesting the poor mucosal immunogenicity of p17-MAb-LTB complexes may be related to the instability of recombinant p17 in the mucosal environment. Further investigations into the stability of other recombinant SIV proteins in the mucosa, revealed that recombinant p27 was more resilient to mucosal degradation. p27-MAb-LTB complexes were constructed and initial intranasal immunisation studies revealed that both systemic and cell-mediated immunity to recombinant p27, could be induced following intranasal administration. Furthermore, mucosal immunity to recombinant p27 was evident in the lungs of vaccinated mice, with anti-recombinant p27 IgG-secreting cells predominating.

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ISIDRO, E. G. C. "Modelos Simples de Lemaitre - Tolman - Bondi (LTB)". Universidade Federal do Espírito Santo, 2015. http://repositorio.ufes.br/handle/10/7459.

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O modelo padrão atual da cosmologia, o modelo ΛCDM (Λ-Cold Dark Matter), está baseada nas soluções homogêneas de Friedmann-Lemaître-Robertson-Walker (FLRW) das equações de Einstein. As características da Cosmic Microwave Background (CMB) e da formação de estrutura em grandes escalas, são estudadas através da teoria das perturbações cosmológicas no fundo homogêneo e isotrópico. No entanto, nos últimos quinze anos, modelos cosmológicos inomogêneos "simples"que são generalizações do modelo cosmológico FLRW ganharam interesse na comunidade astrofísica e têm sido utilizados para estudar fenômenos cosmológicos. Alguns autores demonstraram que estes modelos inomogêneos com simetria esférica e com fonte de poeira podem reproduzir um bom ajuste para os dados de supernovas do tipo Ia (SNIa) e a posição do primeiro pico da CMB. Estes modelos sugerem que a aparente expansão acelerada do Universo não é causada pela gravidade repulsiva devido à energia escura, mas é sim o resultado das inomogeneidades na distribuição da matéria. Nesta dissertação, os modelos inomogêneos do Universo são investigados na base da métrica de Lemaître-Tolman-Bondi (LTB), o que representa uma solução com simetria esférica para poeira. Dois modelos particulares são estudados: a evolução parabólica com tempo de Big Bang inomogêneo e a evolução hiperbólica com curvatura fraca e tempo de Big Bang constante. As propriedades de cada um destes modelos são investigadas em detalhe, da forma mais analítica possível. Ambos modelos são confrontados com observações astrofísicas da amostra Union2.1 SNIa. Conclui-se que esses modelos podem ser um ponto de partida para desenvolver modelos mais realistas. Portanto, a solução de LTB é capaz de explicar a relação observada entre a distância de luminosidade e o desvio para o vermelho de supernovas sem a necesidade da energia escura quando a inomogeneidade é da forma de um vazio ou quando se tem uma colina centrada no observador com a suposição adicional de que o Universo fora do vazio ou fora da colina é aproximadamente descrito pelo modelo de Einstein-de Sitter homogéneo.

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Harmon, C. Reid. "IPU/LTB a method for reducing effective memory latency /". Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04072004-180020/unrestricted/harmon%5Fc%5Fr%5F200312%Fphd.pdf.

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Maciel, Liana Flores. "Desenvolvimento de vacina recombinante de proteína M de Streptococcus equi subsp. equi". Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/1199.

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The business related to equines in Brazil has an important participation in activities as leisure, culture and tourism, being responsible for millions of jobs. The equine distemper caused by Streptococcus equi subsp. equi is a disease of the respiratory tract with economical impact, generating losses with treatment and reduction in the animal performance. To solve this problem, prophylactic measures, such as the vaccination, are important. However, available commercial vaccines do not offer protection to more than 50% of the vaccinated animals. Several studies are being performed aiming the achievement of an efficient vaccine against the Adenitis, where several virulence factors are being evaluated as possible vaccine antigens, specially the M protein (SeM). Thus, the present work aimed the development and evaluation of a recombinant vaccine to the control of the equine distemper composed of the SeM antigen co-administrated with the recombinant Heat-labile enterotoxin B subunit of Escherichia coli (rLTB) and/or aluminium hydroxide (Al(OH)3). A total of 72 female BALB/c mice, divided into eight groups and 18 horses, divided into six groups, were inoculated by intramuscular or intranasal routes. The results obtained in the experiments showed that the rSeM was innocuous and immunogenic in both evaluated species, stimulating the production of specific immunoglobulin anti-rSeM without the addition of immunological adjuvant. Both adjuvant rLTB and Al(OH)3 were not capable to increase the titer of immunoglobulin anti-rSeM in mice, while in horses, the treatment rSeM + rLTB (IM) showed a significant increase in the level of seric immunoglobulin IgG anti-rSeM. Interestingly, the production of anti-rSeM secretory IgA in the upper respiratory tract has a significant increase in horses treated with rSeM + Al(OH)3 (IM). This result is promising to further studies with rSeM as an antigen for vaccines, as well as is the administration of rLTB as an immunological adjuvant.
A equinocultura no Brasil ganha espaço em setores ligados ao lazer, cultura e turismo, sendo responsável por milhões de empregos. A Adenite Equina causada pelo Streptococcus equi subsp. equi é uma doença do aparelho respiratório de elevado impacto econômico, gerando gastos com mão-de-obra e perda de desempenho dos animais. Para amenizar este problema, medidas profiláticas são importantes, como por exemplo, a vacinação. Porém, as vacinas disponíveis no mercado protegem apenas 50% dos animais. Vários estudos vêm sendo realizados para obtenção de uma vacina mais eficiente contra a Adenite, onde vários fatores de virulência do patógeno estão sendo avaliados como possíveis antígenos vacinais, com destaque para a proteína M de S. equi (SeM). Com base nisso este trabalho objetivou o desenvolvimento e avaliação de uma vacina recombinante para controle da Adenite Equina, utilizando como antígeno a rSeM e como adjuvantes a subunidade B da enterotoxina termolábil de Escherichia coli (rLTB) e ou hidróxido de alumínio (Al(OH)3). Para este estudo foram utilizados 72 camundongos Balb/c fêmeas divididos em 8 grupos e 18 cavalos divididos em 6 grupos, inoculados por via IM ou IN. Os resultados mostraram que a rSeM foi inócua e imunogênica para ambas as espécies avaliadas, estimulando níveis significativos de imunoglobulinas (lgs) anti-rSeM sem a necessidade de uso de qualquer adjuvante imunológico. Os adjuvantes rLTB e Al(OH)3 não foram capazes de incrementar significativamente os títulos de lgs antirSeM em camundongos, enquanto que em cavalos o tratamento rSeM + rLTB (IM) promoveu um aumento significativo no título sérico de IgG anti-rSeM. Interessantemente, a produção de IgA secretória anti-rSeM no trato respiratório superior de cavalos teve aumento significativo no tratamento com rSeM + Al(OH)3 (IM). Estes resultados são promissores para a continuidade de estudos visando a utilização da rSeM como antígeno vacinal. Da mesma forma, o uso da rLTB como adjuvante em vacinas para cavalos parece ser promissor.

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Klafke, Gabriel Baracy. "Integração e expressão do gene ltb-r1 em plantas de tabaco". Universidade Federal de Pelotas, 2010. http://repositorio.ufpel.edu.br/handle/ri/1282.

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During the past decades, the development of genetically modified plants became a consolidated reality. Taking advantage of the genetic engineering process, it is possible to obtain modified plants to use as bioreactors in the production of tissue or organs expressing antigens which can be easily used as vaccines. The plant-based expression systems as tomato and lettuce, which attend as models for that process, present innumerous advantages such as conservation of eukaryotic machinery, which promote pos-translational modifications, possibility of large-scale production and development of safer and economically more attractive vaccines. Taking use of that strategy, the Swine mycoplasm hyopneumoniae (SMP) disease can be one important and possible target to either be eradicated or controlled. The SMP, caused by fastidious bacterium Mycoplasma hyopneumoniae, is one of the most important respiratory disease in swine breeding, due to its very high prevalence coupled with associated losses all over the whorld, and has in the recombinant DNA technology a viable alternative in the development of more effective and safe vaccines The objective of my work was to genetically manipulate tobacco plants in order to use them as bioreactor in the production of an antigen against PMS. Tobacco leaves and internodes were cultured in different concentrations of BAP and AIA hormones. The best regeneration results for both explants were seen with 1,5mg.L-1 BAP and 0,1mg.L-1 AIA. The selection test with the kanamycin antibiotic appeared to be highly effective, showing a total inhibition of regeneration with 30 mg.L-1 and 100 mg.L-1 for leaves and internodes respectively. The recombinant colonies of A. tumefaciens, containing ltb-r, were co-cultivated with the internodes and leaves from plants germinated in vitro. The next step, the explants were transferred to the selection medium in order to induce the selection of the putatively transformed cells. The genomic DNA from regenerated and putatively transformed plants were extracted and amplified by PCR, where it was detected the presence of a band referent to ltb r1. The analyses of the integration and the transcription of ltb-r1 were carried out by Southern blot and RT-PCR, respectively. In both techniques, it was possible to confirm the presence of one band which corresponds to the expected size of ltb-r1, supporting the integration and expression of the gene. However, with the tests used here, it was not possible to detect with accuracy the recombinant protein
Nas últimas décadas, o desenvolvimento de plantas geneticamente modificadas tornou-se uma realidade consolidada. Nesse sentido, utilizando-se da engenharia genética, é possível obter plantas servindo como biorreatores na produção de tecidos ou orgãos expressando antígenos que podem ser facilmente utilizados como vacina. Os sistemas de expressão em plantas como tomate, alface, tabaco que servem como modelos desse processo, apresentam várias vantagens, entre elas, a conservação da maquinaria eucariótica que promove as modificações póstraducionais das proteínas e ainda a possibilidade de produção em larga escala. Dentro desta estratégia de produção de proteínas, pode-se citar a pneumonia micoplásmica suína (PMS), causada pelo agente Mycoplasma hyopneumoniae, uma das principais doenças de suínos que provoca elevadas perdas econômicas em todo mundo, e tem, na tecnologia do DNA recombinante, uma alternativa de desenvolvimento de vacinas mais efetivas. O objetivo do trabalho foi transformar plantas de tabaco para sua utilização como biorreator na produção de um antígeno vacinal contra a PMS. Folhas e entrenós foram cultivados em diferentes concentrações de BAP e AIA. As melhores taxas de regeneração foram encontradas utilizando 1,5 mg.L-1 de BAP e 0,1 mg.L-1 de AIA para segmentos de folhas e entrenós. O teste de seleção utilizando canamicina mostrou-se altamente eficiente, obtendo-se a supressão da regeneração com 30 mg.L-1 e 100 mg.L-1 para segmentos de folhas e entrenós, respectivamente. Colônias recombinantes de A. tumefaciens contendo ltb-r1 foram co-cultivadas com entrenós e segmentos foliares de plantas germinadas in vitro. Após esta etapa, os explantes foram transferidos para meios de seleção, visando selecionar células possivelmente transformadas. O DNA genômico das plantas regeneradas e putativamente transformadas foi extraído e amplificado por PCR, na qual foi possível visualizar uma banda referente ao ltb-r1. A detecção da integração e transcrição do gene foi realizada por Southern blot e RTPCR, respectivamente. Em ambas as técnicas, foi possível verificar a presença de uma banda do tamanho esperado para ltb-r1, demonstrando assim, a integração e expressão do gene. Entretanto, não foi possível detectar com precisão, através dos testes utilizados, a proteína recombinante.

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Grassmann, André Alex. "Proteção contra leptospirose induzida por LipL32 coadministrada ou fusionada à LTB". Universidade Federal de Pelotas, 2011. http://guaiaca.ufpel.edu.br/handle/123456789/1285.

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Leptospirosis is an infectious disease that affects humans, wild and domestic animals worldwide. Pathogenic spirochetes from the Leptospira genus are the causative agents of this zoonosis. The several Leptospira species have noted antigenic diversity, even within the same species. This is the main reason current bacterin vaccines have limitations, such as adverse effects and short term immunity, restricting their use in human populations. The need for effective leptospirosis vaccines promoted studies on characterization of new vaccine candidates. The 32 kDa outer membrane lipoprotein, LipL32, is the most abundant protein in the whole leptospira proteome, it is conserved in all pathogenic serovars and absent in saprophytes. This protein is immunogenic and able to bind to mammalian extracellular matrix. However, LipL32 subunit vaccines did not protect animals against challenge. In an attempt to solve this, we use LipL32 fused and coadministered with B subunit of the Escherichia coli heat-labile enterotoxin (LTB) to enhance the immune response. LTB is a non-toxic molecule with immunoestimulatory and immunomodulatory properties. The recombinant proteins rLTB, rLipL32 and rLTB::LipL32 were expressed in E. coli, purified and characterized. Female hamsters were distributed in groups as follows: rLTB; rLTB+rLipL32; rLTB::LipL32, homologous bacterin; PBS. The serum from each animal was collected for humoral immune response determination by ELISA. The animals were challenged with 5×LD50 dose of Leptospira interrogans strain Fiocruz L1-130. Both treatments induced high titers of anti-rLipL32 antibodies. The rLTB+rLipL32 and rLTB::LipL32 treatments afforded significant protective response upon challenge, when compared to control groups (p<0.05). No prior study with leptospirosis had used LTB as the adjuvant, or fused antigens in an attempt to control this disease. Furthermore, this is the first report of a protective subunit vaccine using rLipL32 as the antigen, and an important contribution towards the development of improved leptospirosis vaccines.
A leptospirose é uma doença infecciosa que afeta humanos e animais silvestres e domésticos em todo mundo. As espiroquetas patogênicas do gênero Leptospira são os agentes causadores desta zoonose. As diversas espécies de leptospiras possuem notada diversidade antigênica, inclusive em uma mesma espécie. Esta característica resulta em limitação das atuais vacinas bacterinas que não induzem proteção cruzada entre os diferentes sorovares. Além disso, estas vacinas geram efeitos adversos e imunidade de curta duração, restringindo seu uso em populações humanas. A necessidade de novas vacinas eficazes contra a leptospirose estimulou estudos para caracterizar novos antígenos vacinais. A lipoproteína de membrana externa de 32 kDa, LipL32 é a proteína mais abundante no proteoma total da leptospira, conservada entre todos os sorovares patogênicos e ausente nas leptospiras saprófitas. Esta proteína é imunogênica e possui habilidade de ligar-se à matriz extracelular de mamíferos. Porém, animais inoculados com vacinas de subunidade utilizando LipL32 não sobrevivem ao desafio. Em função disso, utilizamos LipL32 fusionada e co-administrada com a subunidade B da enterotoxina termolábil de Escherichia coli (LTB) para melhorar a resposta imune. LTB é uma molécula atóxica com reconhecida atividade imunoestimuladora e imunomoduladora. As proteínas recombinantes rLTB, rLipL32 e rLTB::LipL32 foram produzidas em E. coli, purificadas e caracterizadas. Hamsters fêmeas foram distribuídas em grupos e inoculadas com duas doses, da seguinte forma: rLTB; rLTB+rLipL32; rLTB::LipL32, bacterina homóloga e PBS. Soro foi coletado individualmente para determinação da resposta imune humoral por ELISA. Os animais foram desafiados com uma dose de 5×DL50 de Leptospira interrogans cepa Fiocruz L1-130. Os tratamentos induziram altos títulos de anticorpos anti-rLipL32. Os tratamentos rLTB+rLipL32 e rLTB::LipL32 induziram resposta protetora significativa frente ao desafio quando comparados com os grupos controle (p<0,05). Nenhum estudo anterior usou LTB como adjuvante para uma vacina contra leptospirose, tampouco antígenos fusionados com o intuito de controlar esta doença. Além disso, este é o primeiro relato de indução de imunidade protetora utilizando rLipL32 como vacina de subunidade, uma importante contribuição para o desenvolvimento de vacinas mais eficazes contra leptospirose.

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Petrie, Allan Gilmour. "Potential of PLG and LTB for oral delivery of antigens to salmonids". Thesis, University of Aberdeen, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401271.

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Biocompatible polymer poly(lactide-co-glycolide) (PLG) and Escherichia coli heat labile enterotoxin B-subunit (LTB) were investigated with regards to their potential for delivering antigens following oral delivery to salmonids. A commercial immersion vaccine against furunculosis was encapsulated within PLG microparticles and delivered to Atlantic salmon by oral intubation and intra-peritoneal injection. Following delivery, antibody responses and protection against lethal challenge with Aeromona salmonicida were minimal. SEM and protein studies of particles indicated that encapsulation of bacterial cells was sub-optimal. Adjuvant effect of PLG microparticles containing a model protein antigen (human gamma-globulin) was investigated following intra-peritoneal injection to rainbow trout. Release of protein from the microparticles was determined in-vitro. Specific antibodies were determined at set time points following injection by ELISA and no detectable immune response was measured in fish where protein encapsulated within PLG was delivered. This may be explained by the fact that in-vitro release of HGG from microparticles over the experimental period was minimal. The ability of Atlantic salmon to take up microparticles was investigated following anal and oral intubation of fluorescent microspheres of known sizes. Following anal intubation, microspheres in the range of 0.1 to 3mm, were detected within spleen and kidney sections. The route of uptake of microspheres was not determined. Following oral intubation, microspheres were detected within the hindgut lumen, although not to the same degree as following anal intubation, and no microspheres were detected within kidney or spleen sections. Incorporation of plasmid DNA vaccine into microparticles or adsorption onto positively charged microparticles were investigated. Both encapsulation within and adsorption onto charged PLG microparticles was demonstrated although technical difficulties were incurred in producing quantities sufficient for immunisation studies. The potential of LTB as an antigen carrier molecule was investigated using recombinant LTB produced within transgenic potato tubers.

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Gravier, Christine. "Synthèse du leucotriène (+)-LTB et d'un analogue à partir du D-mannitol". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37598017q.

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Elbelrhiti, Elalaoui Abdelbaki Fontana Marc. "Spectroscopie Raman et étude des propriétés électrooptiques du Tétraborate de Lithium Li2B4O7(LTB)". Metz : Université Metz, 2008. ftp://ftp.scd.univ-metz.fr/pub/Theses/2002/Elbelrhitti_Elalaoui.Abdelbaki.SMZ0215.pdf.

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Gravier-Pelletier, Christine. "Synthese du leucotriene enantiomeriquement pru ltb quatre et d'un analogue a partir du d-manniotol". Paris 6, 1986. http://www.theses.fr/1986PA066507.

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Birru, Yitaferu. "Land degradation and options for sustainable land management in the Lake Tana Basin (LTB), Amhara Region, Ethiopia /". Bern : [s.n.], 2008. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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Gil, Luciana Aquini Fernandes. "Produção e caracterização de quimeras recombinantes C e D de Clostridium botulinum". Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/2486.

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Bovine Botulism is a lethal intoxication caused by the ingestion of the neurotoxins produced by Clostridium botulinum types C and D that inhibit the release of acetylcholine at the neuromuscular junction leading to death by flaccid paralysis. It produces important economic losses, being a major cause of casualties in cattle in several regions of Brazil. The control of the disease depends on the presence of neutralizing antibodies against botulinum neurotoxins (BONTs) in immunized cattle. Immunization is obtained inoculating toxoids produced from cultures of selected strains of C. botulinum types C and D, whose industrial production has limitations concerning efficiency and productivity. An alternative to the use of these toxoids is the production of recombinant antigens with high levels of purity and antigenicity. The C-terminal fraction of the heavy chain of botulinum neurotoxins has been the main target in the development of recombinant vaccines with promising results. In this work, two recombinant bivalent chimeras for the control of bovine botulism consisting of the neuronal receptor binding domains (NRBDs) of botulinum C and D toxins were efficiently produced in Escherichia coli. They were characterized and evaluated in mice, with promising results. Both the recombinant chimeras rLTB-C-D and rC-D were produced by cloning and expressing a synthetic gene encoding the C-terminal portion of both BONTs. The former also included the preferred codons of the E. coli heat labile enterotoxin B subunit (LTB), a potent humoral immune adjuvant. The levels of expression of the recombinant antigens were satisfactory, yielding approximately 100 mg of each recombinant antigen per liter of culture. An ELISA performed to assess the antigenicity of the molecules showed that both were recognized by sera of immunized mice suggesting the preservation of epitopes with the properties of native BONTs. Both chimeras induced high levels of neutralizing antibodies without undesirable effects. The level of neutralizing antibodies of the groups inoculated with equimolar concentrations of rLTB-C-D and rC-D containing Aluminum Hydroxide as adjuvant were similar, confirming the adjuvant properties of LTB. These results demonstrated that the recombinant chimeras were immunogenic. Sera from mice inoculated with commercial vaccines were also analyzed by ELISA using as antigens rC and rD, corroborating the neutralization.
O botulismo bovino é uma intoxicação letal causada pela ingestão da neurotoxina produzida pelo Clostridium botulinum principalmente dos tipos C e D que atua inibindo a liberação de acetilcolina na junção neuromuscular levando à morte por paralisia flácida, com grande importância econômica e sanitária, sendo uma das principais causas de morte em bovinos adultos no Brasil. O controle imunológico do botulismo bovino depende da presença de anticorpos neutralizantes contra as neurotoxinas botulínicas (NBOTs) no momento da ingestão da toxina pré-formada, por meio de imunização dos animais. Atualmente, a imunização é realizada com toxóides obtidos da detoxificação do extrato de cultivos de cepas selecionadas de C. botulinum dos tipos C e D que apresentam limitações quanto à eficiência e produção. Uma alternativa ao uso dos toxóides clássicos é a produção de vacinas recombinantes usando antígenos específicos de alta pureza e imunogenicidade. A fração C-terminal da cadeia pesada da neurotoxina botulínica tem sido o alvo principal no desenvolvimento de alternativas recombinantes a serem utilizadas como vacinas. Neste trabalho, duas quimeras recombinantes bivalentes compostas pelos domínios de ligação ao receptor neuronal (DLRNs) foram produzidas em Escherichia coli, caracterizadas e avaliadas em camundongos. As quimeras recombinantes rLTB-C-D e rC-D foram produzidas a partir da clonagem e expressão de um gene sintético que codifica a porção C-terminal das NBOTs construído com os códons preferenciais de E. coli e a subunidade B da enterotoxina termolábil de E. coli (LTB), um potente adjuvante da resposta imune humoral. O nível de expressão dos antígenos foi de aproximadamente 100mg de cada antígeno recombinante por litro de cultura. Um ELISA realizado para avaliar a antigenicidade das moléculas mostrou que ambas foram reconhecidas pelos soros padrões, sugerindo conservação de epitopos semelhantes aos dos DLRNs nativos. Ambas as quimeras foram inócuas para os camundongos, os quais não apresentaram lesões no local da inoculação bem como alteração de comportamento. Nos soros dos camundongos inoculados com as quimeras recombinantes foi possível detectar níveis de anticorpos neutralizantes. O grupo inoculado com a rLTB-C-D apresentou nível de anticorpos neutralizantes semelhante ao do grupo rC-D + hidróxido de alumínio confirmando o potencial adjuvante da LTB. As quantidades de antígenos utilizados foram equimolares. Esses resultados demonstram que as quimeras recombinantes foram imunogênicas. Os soros dos camundongos inoculados com as diferentes vacinas também foram analisados por ELISA indireto utilizando rC e rD como antígenos. Os dados obtidos neste ELISA corroboram os dados da soroneutralização.

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Brocchi, Marcelo 1967. "Clonagem e deleção do gene LTb de escherichia coli de origem suina para ser utilizado como carreador de epitopos antigenicos". [s.n.], 1992. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317385.

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Orientador : Wanderley Dias da Silveira
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Mestrado
Genetica
Mestre em Ciências Biológicas

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Pereira, Juliano Lacava. "Expressão heteróloga da quimera LTB/GnRH sintética em Pichia pastoris e seu efeito na resposta imunológica e no epitélio seminífero de camundongos". Universidade Federal de Pelotas, 2011. http://repositorio.ufpel.edu.br/handle/ri/1296.

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Several recombinant proteins have been studied as immunocontraception agents in mammals, among them the Gonadotropin-releasing hormone (GnRH). Nevertheless, due to its low molecular weight, GnRH needs to be conjugated with a carrier protein. Among the eukaryotic platforms the yeast Pichia pastoris, which are able of promoting post-translational modifications to expressed recombinant protein. The aim of this study was to clone and express the GnRH/LTB chimera in P. pastoris, and to test it as an immunocontraceptive. In order to accomplish this, sequences of P. pastoris codons usage were synthesized and cloned into the plasmid pPICZαB. The plasmid containing the sequence were propagated and transformed into yeast by electroporation. The transformed colonies were selected by resistance to antibiotics and confirmed by Colony Blotting. The selected clone was cultivated, induced and the protein expressed in supernatant. The protein was concentrated and used as a vaccine antigen. BALB/c males mice were vaccinated twice 15 apart with 100µg de LTB/GnRH adjuvanted with aluminum hydroxide. The immune response was evaluated by ELISA, showing seraconversion in vaccinated animals. The sperm concentration in the control group was 16.93 x 107 and 8.00 x 107 sperm/mL in the immunized group. Vaccination caused a reduction of spermatogenesis (p < 0,05), vacuolization and disorganization of the seminiferous tubules. We concluded that the yeast was able to express the recombinant protein LTB/GnRH, and it demonstrated immunocontraceptive potential in mice.
Diversas proteínas recombinantes estão sendo pesquisadas para utilização na imunocontracepção de mamíferos. Entre elas, o hormônio liberador de gonadotrofinas (GnRH), entretanto devido ao seu baixo peso molecular há necessidade de associá-lo a uma molécula carreadora. Dentre as plataformas eucarióticas, encontra-se a levedura Pichia pastoris que tem possibilitado expressão e modificações pós-traducionais das proteínas recombinantes. O objetivo deste trabalho foi clonar e expressar a quimera LTB/GnRH em P. pastoris, visando sua utilização como imunocontraceptivo. Para tanto, sequências com os códons preferenciais de P. pastoris da proteína foram sintetizadas e clonada no plasmídeo pPICZαB. O plasmídeo foi propagado e transformado na levedura por eletroporação. As colônias transformadas foram selecionadas por resistência antibiótica e confirmadas por Colony Blotting. O clone selecionado foi cultivado e após indução expressou a proteína no sobrenadante. A proteína foi concentrada e utilizada como antígeno vacinal. Camundongos BALB/c machos foram vacinados com duas doses de 100µg de LTB/GnRH adsorvidas em hidróxido de alumínio com intervalo de 15 dias. A resposta imune foi avaliada por ELISA, mostrando soroconversão nos animais imunizados. A concentração espermática no grupo controle foi 16,93 x 107 e no grupo imunizado 8,00 x 107 espermatozóides/mL. A imunização induziu a redução da espermatogênese (p < 0,05), vacuolização nos túbulos seminíferos e desorganização testicular. Concluiu-se que a levedura foi capaz de expressar a proteína LTB/GnRH recombinante e a mesma apresentou potencial imunocontraceptivo em camundongos.

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Eslabão, Lívia Budziarek. "Avaliação do potencial imunogênico de vacinas contendo GnRH-I recombinante em camundongos machos BALB/c". Universidade Federal de Pelotas, 2016. http://repositorio.ufpel.edu.br:8080/handle/prefix/3733.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
A imunocontracepção é reconhecida como um dos principais novos métodos contraceptivos para o controle e o manejo da fertilidade em diferentes espécies animais. Dentre os potenciais alvos utilizados em vacinas contraceptivas, o hormônio liberador de gonadotrofinas (GnRH) é considerado um dos mais atrativos. O GnRH é um decapeptídeo hipotalâmico que apresenta um papel central na reprodução de mamíferos. Entretanto, devido à sua baixa imunogenicidade, é necessário associar o GnRH com uma molécula carreadora capaz de estimular o sistema imune como, por exemplo, a subunidade B da enterotoxina termolábil de Escherichia coli (LTB). O presente estudo visou avaliar o potencial imunocontraceptivo de duas quimeras LTB/GnRH em camundongos machos da linhagem BALB/c. Os camundongos foram divididos aleatoriamente em oito grupos experimentais. O grupo LTB/GnRH-P recebeu a quimera expressa em P. pastoris. O grupo LTB/GnRH-P/A recebeu a quimera expressa em P. pastoris adsorvida em adjuvante oleoso. O grupo LTB/GnRH-E recebeu a quimera expressa em E. coli. O grupo LTB/GnRH-E/A recebeu a quimera expressa em E. coli adsorvida em adjuvante oleoso. O grupo LTB recebeu a proteína LTB expressa em E. coli. Os grupos Controle e Controle/A não receberam nenhum antígeno vacinal. O grupo Vacina comercial recebeu vacina comercial anti-GnRH utilizada em bovinos. A resposta imune humoral foi avaliada pela técnica de ELISA indireto e o potencial imunocontraceptivo foi avaliado por meio da quantificação de testosterona sérica e das análises histológicas das gônadas dos animais. Os grupos que receberam os antígenos LTB/GnRH (25 μg por vacina) apresentaram níveis de IgG total significativamente superiores quando comparados aos grupos controle, mostrando que ambos os antígenos são imunogênicos. Os grupos LTB/GnRH-P e LTB/GnRH-P/A apresentaram as maiores absorbâncias nos dias 28 (1,11 ± 0,09) e 42 (1,44 ± 0,04), respectivamente. Além disso, o grupo LTB/GnRH-P/A apresentou níveis de testosterona significativamente menores ao controle a partir do dia 28 (192 ng/dl ± 254,55). Os grupos LTB/GnRH-E e LTB/GnRH-E/A também obtiveram os maiores níveis de anticorpos nos dias 28 (0,33 ± 0,005) e 42 (1,44 ± 0,08), respectivamente. O grupo LTB/GnRH-E/A apresentou níveis de testosterona significativamente menores ao controle a partir do dia 28 (<12 ng/dl ± 0). Os resultados da histologia mostraram que ambos os antígenos causam alterações na espermatogênese, sendo que o antígeno expresso em E. coli foi relacionado com as maiores alterações nas gônadas. O presente estudo mostrou quimeras produzidas através da fusão da LTB com uma única molécula de GnRH é capaz de induzir a geração de resposta imune humoral, bloqueio das funções endócrinas relacionadas com a reprodução e alterações teciduais nas gônadas de camundongos machos.
Immunocontraception is recognized as one of the major new contraceptive methods for the control and management of fertility in different animal species. Among the potential targets used in contraceptive vaccines, gonadotropin-releasing hormone (GnRH) is considered one of the most attractive. GnRH is a hypothalamic decapeptide that presents a central role in mammalian reproduction. However, due to its low immunogenicity, it is necessary to associate the GnRH with a carrier molecule capable of stimulating the immune system such as, for example, the B subunit of Escherichia coli heat-labile enterotoxin (LTB). The present study aimed to evaluate the immunocontraceptive potential of two LTB/GnRH chimeras in male BALB/c mice. Mice were randomly divided into eight experimental groups. The LTB/GnRH-P group received the chimera expressed in P. pastoris. The LTB/GnRH-P/A group received the chimera expressed in P. pastoris adsorbed in oil adjuvant. The LTB/GnRH-E group received the chimera expressed in E. coli. The LTB/GnRH-E/A group received the chimera expressed in E. coli adsorbed in oil adjuvant. The Control and Control/A groups did not receive vaccine antigen. The Commercial vaccine group received an anti-GnRH commercial vaccine used in cattle. The humoral immune response was evaluated by indirect ELISA and the immunocontraceptive potential was assessed through the quantification of serum testosterone and the histological analysis of animal’s gonads. The groups that received LTB/GnRH antigens (25 μg per vaccine) presented total IgG levels significantly higher when compared to the control groups, showing that both antigens are immunogenic. The LTB/GnRH-P and LTB/GnRH-P/A groups showed higher absorbances at days 28 (1,11 ± 0,09) and 42 (1,44 ± 0,04), respectively. Furthermore, the LTB/GnRH-P/A group presented testosterone levels significantly lower to the control from day 28 (192 ng/dl ± 254,55). The LTB/GnRH-E and LTB/GnRH-E/A groups also obtained the highest antibody levels at days 28 (0,33 ± 0,005) and 42 (1,44 ± 0,08), respectively. The LTB/GnRH-E/A group presented testosterone levels significantly lower to the control from day 28 (<12 ng/dl ± 0). The results from histology showed that both antigens cause changes in spermatogenesis, wherein the antigen expressed in E. coli was associated with major changes in gonads. The present study showed that chimeras produced through the merge of LTB with a single GnRH molecule is capable to induce the generation of humoral immune response, block of the endocrine functions related to reproduction, and tissue alterations in the gonads of male mice.

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SANTOS, JUNIOR Alceu Gonçalves dos. "Produção de Quimera de roptria 2 de Neospora caninum com a porção B da toxina termolábil de Escherichia coli enterotoxigênica (rROP²/LTB) como imunobiológico". Universidade Federal de Pelotas, 2013. http://repositorio.ufpel.edu.br/handle/ri/2488.

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The intracellular protozoan Neospora caninum, is considered the main causative agent of abortion in cattle. Infection occurs by ingestion of sporulated oocysts in the environment, first occurs systemic parasitemy characterizing acute phase of infection and subsequent chronic phase with formation of tissue cysts, thus persisting the infected and the asymptomatic host. Diagnosis is made by serologic tests. Currently, there are no data to ensure the effectiveness of commercial vaccine available for cattle. Apical complex antigens of the parasite are being studied, since they have an important role in infection. The rhoptries, secretory glands present in this region of the parasite N. caninum, play an important role in invasion and formation of parasitophago vacuoles, these properties have generated interest in its use in experimental vaccine formulations. Experimentally it showed partial results of protection in challenge, when fused to other proteins of this protozoan, the protection was increased, suggesting that antigens fusion is effective for protection against N. caninum. This work produced a new chimeric antigen, originated from the fusion of ROP² N. caninum with the B subunit of heat labile enterotoxin of Escherichia coli. The construction of the chimera was accomplished by cloning in sequence where ROP² gene was inserted directly into the N-terminus of LTB. The construction ROP²/LTB was expressed in E. coli strain BL 21 (DE3) StarTM where it presented a size of approximately 24kDa. The fusion antigen did not impair the antigenicity when tested against positive bovine serum by immunofluorescence, the Western blot technique, therefore, show great potential for use as a recombinant vaccine.
O protozoário intracelular Neospora caninum, é considerado principal agentes causadores de aborto em bovinos. A infecção ocorre pela ingestão de oocistos esporulados no ambiente, inicialmente ocorre parasitemia sistêmica caracterizando fase aguda da infecção e posteriormente fase crônica com formação de cistos teciduais, permanecendo assim o hospedeiro infectado e assintomático. O diagnóstico é feito através de provas sorológicas. Atualmente, não há dados que assegurem a eficácia da vacina comercial disponível para bovinos. Antígenos do complexo apical do parasito estão sendo estudados, pois apresentam papel importante na infecção. As roptrias, glândulas secretoras presente nesta região do parasito N. caninum, desempenham papel importante na invasão e formação do vacúolo parasitófago, essas propriedades produziram interesse na sua utilização em formulações de vacina experimentais. Experimentalmente apresentou resultados parciais de proteção ao desafio, quando fusionada a outras proteínas deste protozoário, aumentou a proteção, sugerindo que fusão de antígenos é eficiente para proteção contra N. caninum. O presente trabalho produziu um novo antígeno quimérico, originado da fusão entre ROP² de N. caninum com a subunidade B, da enterotoxina termolábil de Escherichia coli. A construção da quimera foi realizada por clonagem em sequência, onde gene ROP² foi inserido diretamente na porção N-terminal da LTB. A construção, ROP²/LTB, foi expressa em cepa E. coli BL 21 (DE3) StarTM onde apresentou tamanho de aproximadamente 24kDa. A fusão de antígeno não prejudicou a antigenicidade quando testado frente a soro bovino positivo por Imunofluorescência, na técnica de Western blot, portanto, apresentando grande potencial para ser utilizado como vacina recombinante.

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Conceição, Fabrício Rochedo. "Produção e avaliação de uma vacina de subunidade recombinante contra a pneumonia enzoótica suína". Universidade Federal de Pelotas, 2005. http://guaiaca.ufpel.edu.br/handle/123456789/1242.

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SUMMARY CONCEIÇÃO, FABRICIO ROCHEDO, Universidade Federal de Pelotas, may 2005. Production and Evaluation of Recombinant Subunit Vaccine Against Swine Enzootic Pneumonia. Advisor: Odir Antônio Dellagostin. Co-Advisor: Swine Enzootic Pneumonia (SEP), caused by bacterium Mycoplasma hyopneumoniae, is the most important respiratory disease in swine breeding. The commonly used vaccines to control this disease consist of bacterins, whose production cost is high and the efficiency is limited. The objective of this study was to develop and to evaluate a new alternative for controlling SEP, based on a recombinant subunit vaccine (rLTBR1) containing the R1 region of P97 adhesin of Mycoplasma hyopneumoniae (R1) fused to the B subunit of the heat-labile enterotoxin of Escherichia coli (LTB). rLTBR1 formed functional oligomers that presented high affinity to GM1 ganglioside. Mice inoculated with rLTBR1 (IN or IM) produced high levels of anti-R1 systemic and mucosal (sIgA) antibodies, which recognized the native P97. On the other hand, mice inoculated with the commercial bacterin did not produce anti-R1 antibodies. The administration route influenced the modulation of the immune response by LTB, showing that IM rLTBR1 induced Th2-biased immune responses and IN rLTBR1 induced Th1-biased immune responses. IN rLTBR1 also induced IFN-γ secretion by lymphocytes. The rLTB showed to be a powerful mucosal adjuvant, stimulating the production of anti-R1 IgA in trachea and bronchi from mice inoculated with rLTBR1 by parenteral route (IM). rLTBR1 may constitute a new strategy for preventing infection by Mycoplasma hyopneumoniae and may have potential for developing vaccines against other infectious diseases as well. Now a day, the efficacy of this vaccine is being evaluated in specific pathogen free swine.
A Pneumonia Enzoótica Suína (PES), causada pela bactéria Mycoplasma hyopneumoniae, é a doença respiratória mais importante na suinocultura. As vacinas convencionais utilizadas para controlar esta doença consistem de bacterinas, que apresentam custo de produção elevado e eficiência limitada. O objetivo deste estudo foi desenvolver e avaliar uma nova alternativa para controlar a PES, baseada em uma vacina de subunidade recombinante (rLTBR1) composta pela região R1 da adesina P97 de Mycoplasma hyopneumoniae (R1) fusionada a subunidade B da enterotoxina termolábil de Escherichia coli (LTB). rLTBR1 formou oligômeros funcionais que apresentaram alta afinidade pelo gangliosídeo GM1. Camundongos inoculados com rLTBR1 (I.M. ou I.N.) produziram altos níveis de anticorpos sistêmicos e de mucosa anti-R1, os quais reconheceram a P97 nativa. Por outro lado, os camundongos inoculados com a bacterina comercial não produziram anticorpos anti-R1. A rota de administração influenciou a modulação da resposta imune pela LTB, demonstrando que a rLTBR1 I.M. induziu uma resposta do tipo Th2 e a rLTBR1 I.N. do tipo Th1. rLTBR1 I.N. também induziu a secreção de IFN-γ por linfócitos. A rLTB demonstrou ser um potente adjuvante da imunidade de mucosa, estimulando a produção de IgA anti-R1 na traquéia e brônquios de camundongos inoculados com rLTBR1 através de rota parenteral (I.M.). A rLTBR1 pode constituir uma nova ferramenta para prevenir a infecção por M. hyopneumoniae, sendo que a estratégia utilizada pode ser aplicada no desenvolvimento de vacinas contra outras doenças infecciosas. Atualmente, a eficácia da rLTBR1 está sendo avaliada em suínos livres de patógenos específicos. rLTBR1; P97; LTB.

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Lambert, Karine. "Implication d'un motif dileucine de l'hélice VIII du récepteur de haute affinité du LTB[indice inférieur 4] dans la chimiotaxie du neutrophile dépendante de RhoA". Mémoire, Université de Sherbrooke, 2007. http://savoirs.usherbrooke.ca/handle/11143/3881.

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La chimiotaxie des leucocytes implique plusieurs évènements structurels et biochimiques bien organisés. Nous avons étudié les voies de signalisation intracellulaires menant à la migration des neutrophiles impliquant le récepteur de haute affinité du LTB[indice inférieur 4], le BLTI, ainsi que la relation structure-fonction de la huitième hélice alpha du récepteur dans la migration des neutrophiles. Des neutrophiles humains de même que la lignée cellulaire humaine pro-myéloide PLB-985 transfectée de façon stable avec l'ADNc du BLTI humain (PLB-BLT) ou des mutants de substitution de l'hélice 8 du BLTI et différenciée en type neutrophile ont été utilisés lors de cette étude. Tous les récepteurs mutés étaient exprimés à la membrane plasmique à un niveau similaire au récepteur BLTI de type sauvage, déterminé par cytométrie de flux. Les réponses chimiotactiques vers le LTB[indice inférieur 4] étaient similaires pour les PLB-BLT différentiés et les neutrophiles. Cependant, les réponses chimiotactiques des mutants de l'hélice 8 du BLTI vers le LTB[indice inférieur 4] étaient significativement réduites. Le prétraitement des cellules PLB-BLT différenciées et des neutrophiles avec la toxine de pertussis ou les inhibiteurs pharmacologiques de la P13K ou de pl60-ROCK réduisait leur migration vers le LTB[indice inférieur 4], indiquant l'implication de G[alpha][indice inférieur i], P13K et RhoA dans la chimiotaxie induite par le LTB 4 . Les neutrophiles et les PLB-BLT différenciés répondait au LTB[indice inférieur 4] en adoptant une morphologie polarisée, avec la F-actine dans un pseudopode situé au pôle avant et des complexes contractiles actine-myosine à l'arrière et aux côtés de la cellule.La stimulation de cellules PLB-BLT 2L(304-305)/A différentiées avec le LTB[indice inférieur 4] menait à une formation de multiples pseudopodes accompagnée par une perte de migration. Le phénotype de multiples pseudopodes se produisait aussi quand les cellules PLB-BLT étaient transfectées de façon transitoire avec un dominant négatif de RhoA ou prétraitées avec l'inhibiteur de p160-ROCK, Y-27632. Le défaut de migration observé chez les cellules PLB-BLT 2L(304-305)/A était corrigé par la transfection transitoire avec une forme constitutivement active de RhoA. En résumé, nos résultats suggèrent un rôle essentiel du motif dileucine distal de l'hélice 8 du BLT1 dans l'activation de RhoA et permettant la migration normale des neutrophiles induite par le LTB[indice inférieur 4.

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Bénard, Marie-Carole Mélinda. "Conséquences de l'infection à cytomégalovirus sur le placenta humain". Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2355/.

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Le Cytomégalovirus humain (HCMV) est un membre de la famille des Herpesviridae. L'infection congénitale à HCMV, avec une incidence de 0. 2-2% des naissances vivantes est la première cause d'atteintes neurosensorielles acquises. La transmission materno-fœtale du virus est transplacentaire, hématogène. Le placenta est toujours infecté avant le fœtus et est le siège d'une véritable pathologie qui associe des phénomènes de villite, de fibrose et de nécrose. Elle est peu décrite, notamment en ce qui concerne le mécanisme physiopathologique qui la sous-tend. Notre travail a eu pour objectif de caractériser l'environnement placentaire au cours de l'infection à HCMV. Dans un premier temps, nous avons mis en place un modèle d'histoculture de tissus placentaires. En effet, l'étude de l'infection placentaire sur des modèles animaux est rendu difficile compte tenu de la spécificité d'espèce du HCMV et des particularités anatomiques du placenta humain. Par ailleurs, les modèles in vitro repose essentiellement sur des lignées cellulaires ou des cultures de cytotrophoblastes primaires. Notre modèle, nous a permis d'infecter ex vivo des explants placentaires par une souche clinique de HCMV, le VHL/E et d'étudier ce système complexe sur une durée de 21 jours sans altération anatomique ou fonctionnelle du placenta (Lopez H, Benard M, Davrinche C, Casper C et al. Novel model of placental tissue explants infected by cytomegalovirus reveals different permissiveness in early and term placentae and inhibition of indoleamine 2,3-dioxygenase activity. Placenta. 2011 Jul;32(7):522-30. ) Nous avons ensuite utilisé notre modèle afin d'étudier la pathologie placentaire induite par l'infection à HCMV et en premier lieu la villite. Cette villite est un infiltrat lymphomonocytaire classiquement décrit comme associé à l'infection placentaire à HCMV et susceptible d'être impliqué dans la transmission materno-fœtale. Les mécanismes conduisant à cette villite sont inconnus. A partir de placentas infectés in vivo, ex vivo et de cultures d'HUVECs (cellules endothéliales de veines ombilicales humaines), nous avons montré que le HCMV activait la voie des leucotriènes (LT) et plus précisément la 5-lipoxygénase (5-LO) surtout au niveau des cellules endothéliales chorioniques. La 5-LO est la principale enzyme responsable de la synthèse de LTB4, une puissante chémokine, à l'origine d'une inflammation. Notre étude a montré que la voie des leucotriènes est possiblement impliquée dans les mécanismes à l'origine de la villite (article soumis) Dans un troisième temps, compte tenu de la place des cellules endothèliales à la fois dans le cycle réplicatif du HCMV et dans la constitution de la villite, nous avons étudié l'impact de l'infection à HCMV sur la microvascularisation placentaire. Lors de l'infection à HCMV, nous avons observé une diminution significative de l'expression de CD34, un marqueur de surface présent sur les cellules endothéliales. Cette diminution de la microvascularisation a pu être rattachée à un défaut de migration des cellules endothéliales. Cette anomalie de migration est en rapport avec un stress oxydatif significativement augmenté et une sécrétion très importante d'interleukine-6 (IL-6). Notre étude a permis de mettre en avant le rôle des cellules endothéliales dans la pathologie placentaire provoquée par le HCMV. (manuscrit) Au total, en mettant en place une méthode d'histoculture d'explants placentaires, nous avons étudié le placenta infecté par le HCMV. Nous avons montré que le HCMV est responsable d'une pathologie placentaire avec un remodelage tissulaire, principalement une villite, associée à une activation de la voie des leucotriènes (5-LO/LTB4). Nous avons aussi montré la diminution de la microvascularisation placentaire lors de l'infection, associée à un stress oxydatif et une sécrétion importante d'IL-6
The human cytomegalovirus (HCMV) is a member of the Herpesvirus family. Congenital CMV infection, with an incidence of 0. 2-2 % of live births is the leading cause of acquired sensorineural damage. Maternal-fetal transmission is transplacental, hematogenous. The placenta is always infected before the fetus and is the seat of a real pathology associating villitis, fibrosis and necrosis. Few papers described it, especially regarding the pathophysiological mechanism that underlies it. Our work aimed to characterize the placental environment during CMV infection. At first, we developed an histoculture placental tissue model. Indeed, the study of placental infection in animal models is made difficult due to the CMV species specificity and anatomical features of the human placenta. In addition, in vitro models are based primarily on cell lines or primary cytotrophoblasts cultures. Thanks to our model, we were able to infect ex vivo, placental explants with a clinical strain of CMV, VHL / E and to study this complex system over a period of 21 days without anatomical or functional impairment of the placenta. (Lopez H , Benard M , Davrinche C , Casper C and al. Novel model of placental tissue explants infected by cytomegalovirus reveals different permissiveness in early and term placentae and inhibition of indoleamine 2,3- dioxygenase activity Placenta 2011 Jul ;32 (7):522 -30. ) We then used our model to study the placental pathology induced by CMV infection, mainly the villitis. Villitis is a lymphohistiocytic infiltrates classically described as associated with placental CMV infection and may be involved in maternal-fetal transmission. The mechanisms leading to this villitis are unknown. Using in vivo, ex vivo infected placentas and HUVECs (human umbilical vein endothelial cells) cultures, we showed that CMV activated the leukotrienes (LT) pathway and more specifically the 5-lipoxygenase (5-LO) especially in the chorionic endothelial cells. 5-LO is the main enzyme responsible for the synthesis of LTB4, a potent chemokine that causes inflammation. Our study showed that the leukotriene pathway is possibly involved in the mechanisms underlying the villitis. (submitted) In a third step, given the role of endothelial cells in both the replicative cycle of CMV and the constitution of the villitis, we studied the impact of CMV infection on the placental microvasculature. During CMV infection, we observed a significant decrease in the expression of CD34, a surface marker present on endothelial cells. This decrease in the microvasculature has been linked to a defect in endothelial cell migration. This abnormal migration is related to oxidative stress increased significantly and to a very important secretion of interleukin -6 (IL-6). Our study highlighted the role of endothelial cells in the placental pathology caused by CMV. (manuscript) In total, by implementing a placental explants histoculture method, we studied the CMV-infected placenta. We have shown that CMV is responsible for placental pathology characterized by tissue remodeling, mainly a villitis in connection with activation of the leukotriene pathway (5-LO/LTB4). We also showed the decrease in placental microvasculature during infection, associated with oxidative stress and a significant secretion of IL-6

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20

Piják, Jiří. "Klopení nosníku - analýza specifických případů". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265731.

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Thesis deals with flexural-lateral buckling of asymmetric cross sections, especially assessment according to ČSN EN 1993-1-1. Models are based on bar, shell and solid finite element method. Assessment of software Scia Engineer and RFEM are analysed in bar model. Plate and volume model uses shell and solid elements and initial imperfections. Computing is geometrically nonlinear. Correspondence of bar and plate model is studied. Optimal amplitude is suggested. Simple beam loaded with continuous line loading is taken as an example.

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21

Kemp, Nicola. "Mechanisms underlying the induction of long-term depression in the CA1 region of the hippocampus". Thesis, University of Bristol, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300704.

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22

Santana, Pedro Maia de. "Solu??es de coexist?ncia LTE/Wi-Fi em banda n?o licenciada". PROGRAMA DE P?S-GRADUA??O EM ENGENHARIA EL?TRICA E DE COMPUTA??O, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/24974.

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Este trabalho tem como objetivo realizar um estudo sobre a aplica??o de redes LTE no espectro ISM (Industrial Scientific and Medical) e seu consequente impacto sobre tecnologias comumente coexistentes na mesma faixa de frequ?ncia. Inicialmente, ? realizada uma elucida??o te?rica sobre as regulamenta??es que envolvem o uso de espectro n?o-licenciado. Na sequ?ncia, s?o apresentadas as principais solu??es de coexist?ncia do LTE nesse meio, destacando-se o mecanismo recentemente padronizado pelo 3GPP, o LTE-LBT, e tecnologias espec?ficas de empresas pioneiras na ?rea, tais como a solu??o LTE-DC. Como elemento pr?tico complementar ? investiga??o te?rica inicial, s?o desenvolvidas an?lises de desempenho das respectivas solu??es utilizando o simulador ns-3. A novidade do trabalho ? materializada pela apresenta??o de uma proposta de solu??o para o mecanismo Carrier-Sensing Adaptive Transmission (CSAT). Essa solu??o, baseada em aprendizado de m?quina, visa melhorar o desempenho conjunto dos sistemas que coexistem na faixa ISM. Este trabalho tamb?m prop?e uma solu??o de coexist?ncia do LTE-DC consigo pr?prio a partir de uma abordagem utilizando teoria dos jogos. Essas solu??es s?o comparada com as solu??es cl?ssicas e o seus ganhos s?o evidenciado em cen?rios definidos por ?rg?os de padroniza??o mundial.
This work aims to perform a study about the application of LTE networks in ISM (Industrial Scientific and Medical) spectrum and its impact over technologies that communly coexist in the same frequency range. Initially, it?s made a theoretical elucidation about regulamentations involving the non licensed spectrum usage. In sequence, it?s presented the main LTE coexistence solutions in this field, highlighting the recent mechanism standardized by 3GPP, the LTE-LBT, and specific technologies of pioneering companies in this domain, like LTE-DC solution. As a practical element complementary to the initial theoretical investigation, it?s developed performance analyzes of the respective solutions using ns-3 simulator. The novelty of the work is materialized by the presentation of a solution proposal for the Carrier-Sensing Adaptive Transmission (CSAT). This solution, based on machine learning, aims to improve the joint performance of systems that coexist in the ISM band. This work also propose a solution for LTE-DC self-coexistence by a game theory approach. These solutions are compared to the classical ones and their gains are evidenced in scenarios defined by global standardization institutions.

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23

Hosel, Katarina. "Effects of a Modified 30 Hz Intermittent Theta-Burst Stimulation (iTBS) Protocol on Corticospinal Excitability In Healthy Adults". Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42675.

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Theta-burst stimulation (TBS) is a form of repetitive transcranial magnetic stimulation (TMS) developed to induce neuroplasticity. TBS usually consists of 50 Hz bursts at 5 Hz intervals. When applied intermittently, it can lead to facilitation of motor evoked potentials (MEPs), although these effects can be variable between individuals. Here, we aimed to determine whether a version of intermittent TBS (iTBS) consisting of 30 Hz bursts at 6 Hz intervals would produce less variable modulation. Nineteen healthy adults underwent single-pulse TMS to assess corticomotor excitability at baseline as reflected in MEP amplitude. 30 Hz iTBS was then administered and MEP amplitude was reassessed at 5-, 20- and 45-mins after the iTBS protocol. Compared to baseline, MEPs were significantly facilitated up to 45-min post-iTBS and most participants exhibited the expected facilitation. These observations suggest that 30 Hz/6 Hz iTBS may provide a sound alternative to induce consistent neuromodulatory effects over the commonly used 50 Hz/5 Hz protocol.

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24

Kirkup, Jonathan. "The parliamentary agreement between the Labour Party and the Liberal Party 1977-1978 : 'The Lib-Lab Pact'". Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/42288/.

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This thesis is a chronological case study into the origins, operation and consequences of the Lib-Lab Pact 1977-1978. Cross-party co-operation in British politics since 1945 is assessed. David Steel’s election as Liberal Party leader, his political philosophy and strategy are examined. Concepts of realignment, ‘co-operation strategy’ are explored. The parliamentary and political events together with a detailed assessment of the inter-party negotiations which led the Pact are examined. New perspectives include: the significance of the leader-led nature of the negotiation process; the Labour-Ulster Unionist understanding which ran concurrent with the Pact; the importance of Lib-Lab discussions on devolution which pre-dated the Pact in influencing Steel’s subsequent decision-making. Analysis focuses on the Lib-Lab negotiations into if the Direct Elections to the European Parliament Bill should include a proportional voting system and whether the parliamentary Labour party should be compelled to vote for PR. A key finding of the thesis is that rather than allowing a free vote, as was agreed, the Prime Minister, James Callaghan, was prepared to offer the Liberals a ‘pay roll’ vote; the significance of Michael Foot in this process is also noted. The structure of the Lib-Lab consultative mechanism is reviewed. Case studies include a review of on Liberal policy influence on the Budget 1977 and 1978. The nature of intra-party dissent is reviewed with the difference between Labour and the Liberal parties noted. An examination of the serious internecine conflict is complemented by a reassessment of the role of Christopher Mayhew in this process. The Lib-Lab Pact is reviewed, assessing its affect in influencing Callaghan’s decision not to call a General Election in 1978; its influence on Liberal/Liberal Democrat party strategy, and its importance in the subsequent formation of the triple-lock, as such the thesis highlighting the Pacts relevance to subsequent cross-party understandings.

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25

Hibelot, Catherine. "Etude comparative de deux traitements substitutifs de l'hypothyroidie LT3 et LT4 : répercussions osseuses au bout de un an". Bordeaux 2, 1992. http://www.theses.fr/1992BOR2M032.

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26

Hurst, Katrina M. "Modulation of Synaptic Plasticity: Endocannabinoids and Novel G-protein Coupled Receptors Expression and Translational Effects in Interneurons". BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6940.

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Learning and memory are important processes that occur in the brain. The brain is comprised of neurons that make connections with each other known as synapses. Synaptic plasticity is widely believed to be the physiologic mechanism by which learning and memory occur. Synapses can either be strengthened through a process known as long-term potentiation (LTP) or weakened through long-term depression (LTD). The area of the brain that is most studied for its role in learning and memory is the hippocampus, which has been shown to be involved in memory consolidation. The detection of endocannabinoids and their receptors has opened a whole new field of study in regards to synaptic plasticity. Cannabinoid receptor 1 (CB1) and transient receptor potential vanilloid 1 (TRPV1) are among the commonly studied endocannabinoid receptors found in the central nervous system. In the brain, these receptors' natural ligands, anandamide and 2-arachidonylglycerol (2-AG), are found in abundance. Yet not all forms of observed plasticity are accounted for by just these two receptors, so studies into other G-protein coupled receptors (GPCRs) continues. One GPCR, GPR55 is found in many regions of the brain, as well as lysophosphatidylinositol (LPI), its specific ligand. Here we have researched the role of GPR55 in modulating synaptic plasticity in the hippocampus. Using quantitative reverse transcription PCR and immunohistochemistry, we have found GPR55 to be expressed in the hippocampus with highest expression in pyramidal cells, the main excitatory neurons in the hippocampus. Using field and whole cell electrophysiology, we have investigated its effects on synaptic plasticity, discovering that activation of GPR55 by LPI significantly enhances LTP. In memory behavioral assays there are no significant differences between GPR55 KO mice and wild type littermates, indicating that it may not be involved in endogenous memory processes. However, our electrophysiology data makes GPR55 a potential target for treating memory disorders such as dementia. We have also investigated GPR18 and GPR119 for their potential roles in synaptic plasticity. First, we confirmed their expression in the hippocampus and then investigated the effects of their agonists on plasticity. Another receptor, TRPV1 has been studied to alter plasticity. However, the study of how protein translation and RNA transcription involvement in TRPV1 plasticity in mammals has not been investigated. While translation and transcription are known to be important in many forms of LTP, it is unknown whether these processes are important for TRPV1-induced LTD. We are investigating their necessity via whole cell patching and using translation and transcription inhibitors Anisomycin and Actinomycin D, both previously used in slice electrophysiology.

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27

France, Grace. "Features of NMDA receptor-dependent LTP and LTD in the CA1 area of P14 and adult rat hippocampal slices". Thesis, University of Bristol, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.681550.

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N_methyl-O-aspartate receptors (NMOARs) play a pivotal role in synaptic plasticity in the CA1 region of the hippocampus and NMOAR abnormalities have been implicated in many neuropathological diseases and pathophysiologies. Whilst some forms of longterm potentiation (LTP) and long-term depression (LTD) have long been known to have an NMOAR dependence, the involvement of specific NMOAR subunits in LTP and LTD, especially under development, is still a controversial topic. The aim of this study was to clarify the role of the different NMOAR subunits in L TP and L TO, and to investigate the change in kinase activity involved in L TP induction during development. Furthermore, the effects of a newly synthesised phenanthrene derivative and NMOAR potentiator UBP709 were examined on synaptic plasticity at the CA3-CA 1 synapse. In two-week-old animals LTP induction (100 pulses, 100 Hz) was shown to be NMOAR dependent; however, no dominance of a single subunit was discovered. In contrast, LTD was also NMOAR dependent but required activation of GluN2B containing NMOARs in P14 rats. Kinase activity, which is involved in high frequency stimulation induced LTP, was demonstrated to change with age. A multi kinase pathway exists in P14 rats, but this is downregulated and LTP induction becomes CaMKl1 dependent in adult rats. A transient potentiation lasting approximately thirty minutes, known as short-term potentiation (STP), precedes L TP and is also NMOAR-dependent. Induction of STP is dependent on GluN2B- and GluN20-containing NMOARs as STP decays faster in the presence of Ro 25-6981, a GluN2B preferring antagonist, or UBP145, a GluN20 preferring antagonist. NVP, a GluN2A preferring antagonist, had no effect on STP. The novel NMOAR allosteric potentiator, UBP709, enhanced LTO induced by LFS (1 Hz, 900 pulses) and permitted induction of L TO using a 10Hz paradigm that did not induce L TO under control conditions in slices from P14 slices. In adult and aged rats L TO is not readily induced by LFS. However, application of UBP709 permitted induction of a robust L TO in slices from both adult and aged rats. This effect was shown to be NMOARdependent and, in adult rats, required activation of the GluN2B subunit. In summary, results have shown that CaMKl1 appears to dominate LTP in adulthood with the exception of PKA that is involved in STP, induction of which is dependent on GluN2B/20 subunits. Induction of L TP does not depend on a particular NMOAR-subunit whereas induction of L TO is strictly GluN2B dependent, irrespective of the developmental stage of the preparation. UBP709 appears to be a useful tool to investigate synaptic plasticity, which might 'prove beneficial for targeted development of GluN2B selective modulators.

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28

Soleimani, Hossein. "LTE/LTE-Advanced for Vehicular Safety Applications". Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37840.

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IEEE 802.11p, the known standard for Vehicular Adhoc NETworks (VANETs), suffers from scalability issues and unbounded delay. In addition, the desire to use networks already in existence has created motivation for using cellular networks for vehicular applications. LTE-Advanced is one of the most promising access technologies in the wireless field, providing high data rate, low latency, and a large coverage area. Thus, LTE/LTE-A can be potential access technologies for supporting vehicular applications. Vehicular safety applications are based on broadcasting messages to neighboring vehicles. The vehicle location precision is crucial for safety applications. Thus, the freshness of the information (i.e. vehicle location) at the neighboring vehicles is very important. As LTE is an infrastructure-based network, all transmissions should pass through it. When the load of the network is high compared to the available resources, large delays may occur. The focus of this thesis is to propose solutions to make LTE suitable for vehicular safety applications. The first solution is to adapt the vehicular safety application to be suitable in LTE network. For this purpose, we propose an adaptation of the safety message generation rate. This adaptation uses a queueing model to compute the freshness of the information of vehicles at the destination, based on their message generation rates. It then adjusts the generation periods to provide a similar accuracy for all vehicles. The second approach is to modify the LTE and make it suitable for these kinds of applications. Thus, we proposed a scheduler for LTE which is suitable for vehicular safety applications. It considers the speed and location of the vehicles to allocate the resources to them for the transmission of safety messages. We also studied the message dissemination in the downlink, and proposed an efficient way to deliver the safety messages to the neighboring vehicles. Finally, we propose a scheme that uses both LTE-D2D and LTE-cellular communication for the transmission of safety messages. The centralized location information is used for Device-to-Device (D2D) pair discovery and resource allocation. The proposed scheme provides resource efficiency by enabling the reuse of the resources by vehicles. We also study the effect of the awareness range and period of updating location information at the server on resource usage and accuracy of D2D pair detection.

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29

Hussein, Soran. "Lightweight Security Solutions for LTE/LTE-A Networks". Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112366/document.

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Récemment, le 3GPP (3rd Generation Partnership Project) a standardisé les systèmes LTE/LTE-A (Long Term Evolution/LTE-Advanced) qui ont été approuvés par l'UIT (Union Internationale des Télécommunications) comme des réseaux de télécommunications mobiles de 4éme génération. La sécurité est l'une des questions essentielles qui doivent être traitées avec soin pour protéger les informations de l'opérateur et des utilisateurs. Aussi, le 3GPP a normalisé plusieurs algorithmes et protocoles afin de sécuriser les communications entre les différentes entités du réseau. Cependant, l'augmentation du niveau de sécurité dans ces systèmes ne devrait pas leur imposer des contraintes lourdes telles qu’une grande complexité de calcul ou encore une forte consommation d'énergie. En effet, l'efficacité énergétique est devenue récemment un besoin critique pour les opérateurs afin de réduire l’empreinte écologique et les coûts opérationnels de ces systèmes. Les services de sécurité dans les réseaux mobiles tels que l'authentification, la confidentialité et l'intégrité des données sont le plus souvent effectués en utilisant des techniques cryptographiques. Toutefois, la plupart des solutions standardisées déjà adoptées par le 3GPP dépendent des algorithmes de chiffrement qui possèdent une grande complexité, induisant une consommation énergétique plus élevée dans les différentes entités communicantes du réseau. La confidentialité des données, qui se réfère principalement au fait de s'assurer que l'information n'est accessible qu'à ceux dont l'accès est autorisé, est réalisée au niveau de la sous-couche PDCP (Packet Data Convergence Protocol) de la pile protocolaire de LTE/LTE-A par l'un des trois algorithmes normalisés (EEA1, EEA2 et EEA3). Or, chacun des trois algorithmes exige une forte complexité de calcul car ils reposent sur la théorie de chiffrement de Shannon qui utilise les fonctions de confusion et de diffusion sur plusieurs itérations. Dans cette thèse, nous proposons un nouvel algorithme de confidentialité en utilisant le concept de substitution et de diffusion dans lequel le niveau de sécurité requis est atteint en un seul tour. Par conséquent, la complexité de calcul est considérablement réduite ce qui entraîne une réduction de la consommation d'énergie par les fonctions de chiffrement et de déchiffrement. De plus, la même approche est utilisée pour réduire la complexité des algorithmes 3GPP d'intégrité des données (EIA1, EIA2 et EIA3) dont le concept de chiffrement repose sur les mêmes fonctions complexes. Enfin, nous étudions dans cette thèse le problème d'authentification dans le contexte du paradigme D2D (Device to Device communications) introduit dans les systèmes 4G. Le concept D2D se réfère à la communication directe entre deux terminaux mobiles sans passer par le cœur du réseau. Il constitue un moyen prometteur pour améliorer les performances et réduire la consommation d'énergie dans les réseaux LTE/LTE-A. Toutefois, l'authentification et la dérivation de clé entre deux terminaux mobiles dans le contexte D2D n’ont pas fait l’objet d’études. Aussi, nous proposons un nouveau protocole léger d’authentification et de dérivation de clé permettant d’authentifier les terminaux D2D et de dériver les clés nécessaires à la fois pour le cryptage et pour la protection de l'intégrité des données
Recently, the 3rd Group Project Partnership (3GPP) has developed Long Term Evolution/ Long Term Evolution-Advanced (LTE/LTE-A) systems which have been approved by the International Telecommunication Union (ITU) as 4th Generation (4G) mobile telecommunication networks. Security is one of critical issues which should be handled carefully to protect user's and mobile operator's information. Thus, the 3GPP has standardized algorithms and protocols in order to secure the communications between different entities of the mobile network. However, increasing the security level in such networks should not compel heavy constrains on these networks such as complexity and energy. Indeed, energy efficiency has become recently a critical need for mobile network operators for reduced carbon emissions and operational costs. The security services in mobile networks such as authentication, data confidentiality and data integrity are mostly performed using cryptographic techniques.However, most of the standardized solutions already adopted by the3GPP depend on encryption algorithms which possess high computational complexity which in turn contributes in consuming further energy at the different network communication parties.Data confidentiality which mainly refers to the protection of the user’s information privacy is achieved at the Packet Data Convergence Protocol (PDCP) sub-layer in the LTE/LTE-A protocol stack by one of the three standardized algorithms (EEA1, EEA2 and EEA3). However, each of the three algorithms requires high computational complexity since they rely on Shannon’s theory of encryption algorithms by applying confusion and diffusion for several rounds. In our thesis we propose a novel confidentiality algorithm using the concept of substitution and diffusion in which the required security level is attained in only one round. Consequently the computational complexity is considerably reduced which in return results in reducing the energy consumption during both encryption and decryption procedures. Similarly, the same approach is used to reduce the complexity of 3GPP data integrity algorithms (EIA1, EIA2 and EIA3) which the core cipher rely on the same complex functions. Finally, we investigate in this thesis the authentication issue in Device to Device paradigms proposal in 4G systems. Device to Device communications refer to direct communications between two mobile devices without passing through the core network. They constitute a promising mean to increase the performance and reduce energy consumptions in LTE/LTE-A networks. In such context, the authentication and key derivation between two mobile devices have not been well investigated. Thus, a novel lightweight authentication and key derivation protocol is proposed to authenticate two communicating devices during session establishments as well as deriving necessary keys for both data encryption and integrity protection

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Peñafiel, Pilar, e Ricardo Ávalos. "Socks Lab". Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/147792.

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TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN MARKETING
Pilar Peñafiel [Parte I], Ricardo Ávalos [Parte II]
Existe un tiempo limitado para reflejar y representar el estilo personal. La moda se ha vuelto una forma de representarse e individualizarse y los accesorios dentro del vestuario de las personas han tomado cada vez más protagonismo, ya que la gente busca diferenciarse y expresarse a través de los pequeños detalles como la corbata, lentes, colleras, cinturón e incluso relojes. Hoy el mundo corporativo exige en su mayoría atenerse a un código de vestimenta bastante acotado, por lo que los accesorios se han convertido en modos de individualizarse. Es por esto que cada vez más en lugares de todo el mundo se ha visto un crecimiento en el uso de accesorios anteriormente nombrados, viéndose desarrolladas cada vez más de estas categorías, partiendo por la categoría de relojería, corbatería, cinturones, lentes son categorías ya maduras con gran cantidad de actores participantes y donde el precio promedio se ha visto incrementado durante los años gracias a la innovación tanto en materiales de producción como en diseño. Algo similar se espera por parte de la categoría de los calcetines, si bien esta categoría representa un mercado maduro, que durante muchos años no creció y la mayor innovación fue de parte de las marcas deportivas desarrollando calcetines distintos por tipo de deporte (ejemplo Running y Fútbol). Finalmente se crea una nueva subcategoría que remece esta categoría con baja innovación e involucramiento por parte de los consumidores. En base a esta oportunidad y al fanatismo por esta prenda por parte de Ricardo, funda su propia empresa y crea la marca Socks Lab (que viene de Laboratorio de Calcetines) donde se busca desarrollar distintos tipos de calcetines para las personas de hoy enfocado en crear diseños lúdicos y entretenidos con elementos del día a día o elementos icónicos. Socks Lab ofrece la oportunidad de realizar un statement sutil de su personalidad y de diferenciarse del resto ofreciendo un producto de consumo masivo con diseños únicos diseñados en Chile. Socks Lab permite a las personas reflejar su estilo e individualidad a través de un producto innovador, con diseños creativos. Es una invitación a dejar los calcetines aburridos y atreverse a impresionar a colegas y amigos. En este Plan de Marketing abordaremos la subcategoría de los calcetines con diseño con principal enfoque en el primer año de lanzamiento de la marca en Chile, sus canales de distribución a desarrollar, producto y desarrollo comunicacional.

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31

Merriman, Carolyn. "Abdominal Lab". Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/8530.

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32

Schubert, Michael. "LBB and LBB Research During and After the Crisis". Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6864/.

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The presentation of Dr. Albrecht Sommer, head of the Office for Strategic Issues Berlin/ Brandenburg branch of Deutsche Bundesbank, dealt with the Central Bank’s monetary policy during and post European financial crisis.

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33

Block, Frida. "KIRUNA LAB : the experimental lab of an evolving society". Thesis, Umeå universitet, Arkitekthögskolan vid Umeå universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-171750.

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34

Seno, Maria Silvia. "Composição e morfologia de Feijão Gandu, Lab lab e mucuna". [s.n.], 1993. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316601.

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Orientadores : Angelo Luiz Cortelazzo, Laureci Gomes
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-07-18T15:08:48Z (GMT). No. of bitstreams: 1 Seno_MariaSilvia_M.pdf: 3802184 bytes, checksum: 8927400d2dfe2033b2447bd52839f40f (MD5) Previous issue date: 1993
Resumo: No presente trabalho, foram estudadas três espécies leguminosas: Cajanus cajan, Lab lab purpureum e Mucuna aterrima que pertencem a sub-família Papilionoidae onde se concentram a maioria dos legumes utilizados na alimentação humana. Guandu, Lab lab e Mucuna também são utilizados em forragem e como adubo verde. Pelas análises citoquímicas e bioquímicas foi constatada a presença de duas principais reservas nos cotilédones dessas espécies: amido e proteína. O conteúdo de amido é maior em Guandu com 55,5%, seguido de Lab lab com 53% e Mucuna com 40%, sempre em relaçao a matéria seca (MS). Os métodos citoquímicos e a microscopia de polarização mostraram que os grãos de amido em Lab lab são mais numerosos e apresentam menor tamanho. O material protéico está homogeneamente distribuído ao redor dos grãos de amido, por todo o citoplasma das células. Lab lab foi a espécie com maior conteúdo protéico, com cerca de 25,6% da MS. A análise dos extratos protéicos em SDS-PAGE, revelou inúmeras e muitas diferenças entre as espécies. Guandu apresentou uma proteína característica de 100 KDa e Mucuna pode ser caracterizada pelas proteínas com massa molecular aparente de 36,5, 27,5 e 18,5 KDa. A proteína de 45 KDa foi mais proeminente em Lab lab. Os lipídios eaçúcares livres estão presentes em pequenas quantidades nestas sementes. Através dos cortes citoquímicos e microscopia eletrônica de varredura foi constatado uma estrutura tegumentar lípica, com uma camada paliçadica espessa e com células bastante alongadas. A paliçada apresentou-se metacromática quando corada com AT pH 4,0. devido a presença de substâncias pécticas. Também houve forte coloração com PAS devido à presença de celulose. Nenhuma das espécies apresentou a "Linea Lucida" nas células da testa, caracteristica de sementes impermeáveis à água. A análise cromatográfica revelou um grande conteúdo de glicose, xilose e arabinose nos tegumentos da três espécies. No tegumento de Mucuna, foi detectada a presença de corpos marrons que se tratam possivelmente de taninos. Os dados obtidos na curva de embebição mostraram que Guandu e Lab lab embebem mais rapidamente. Mucuna embebeu mais lentamente e, embora também seja uma espécie com tegumento permeável pode-se aferir que se trata da testa que apresenta maior resistência à entrada de água. Desse modo pode ser sugerido que essa maior resistência seja devida à presença de taninos, que apareceram apenas nessa espécie. Os resultados obtidos foram ainda confrontados com aqueles encontrados em espécies totalmente impermeáveis, cuja anatomia dos tegumentos apresenta inúmeras diferenças com relação as três espécies estudadas
Abstract: In the present work, three leguminous speeies have been sudied: Cajanus eajan, Lab lab purpureum and Mueuna aterrima whieh belong to the sUb-family Papilionoideae where are eoneentrated the most of the legumes used in the human nutrieion. Guanu, Lab lab eMueuna are also used in foragement and as green fertilizer. cioehemieal and bioehemieal analysis have been made and it was find out the presenee of two prineipal reserves in the eotyledons of these speeies: stareh and protein. The eontent of followed by Lab lab with the dry material(DM). The eitoehemieal methods and the polarization mieroseopy indieate that the stareh grains in Lab lab are more numerous and presentes asmaller size. The proteie material presented homogeneously distributed around the stareh grains, in alI the eytoplasm of the eells. Lab lab was the speeie with the major proteie eontent, with about 25,6% of the DM. The proteie extraets analysis in SDS-PAGE revealed inumerable proteins and too mueh diferenees between the speeies. The Guandu presented a earaeteristie protin of 100 KDa and Mueuna may be eharaeterized by the proteins of smaller moleeular weight, like 36,5, 27,5 and 18,5 KDa. The 45 KDa protein was exelusive for Lab lab. The lipidis and free simpler earbohydrates are in low amout in this seeds. Though the eitoehemieal euts and eletronie mieroseopy of sweeping, it was verified one tipieal tegumentar strueture, with a dense layer of palisade and with eells quite elongated. The paliçade beeame metaehromatie when eolored with AT pH 4, O, due to the presenee of peetie substanees. AIso there were a strong eoloration of the PAS due to the presence of celulosys. None of the species showed the "Linea Lucida" in the cells of the testa, caracteristic of water impermeable seeds. The cromografic analisys revealed a great glucose, xylose and arabinose content in the teguments of these three species. In the Mucuna tegument, the presence of brown corps, posibly taninns, was detected. The data obtained in the embibement curve show that Guandu and Lab lab embibes faster. Mucuna embibed more slowly, and although it is also a permeable tegument specie, one can verify that it the testa that presents the major resistence to water entrance. So, it may be sugested that this major resitence is due to the presence of tannins, wich were present in great quantity only in this specie. The obtained results were still confronted with those finded in totaly impermeable species, whose tegument anatomy presents inumerable diferences in relation with the three studied species
Mestrado
Biologia Celular
Mestre em Ciências Biológicas

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35

Nakao, Seigo. "Study of Uplink Control Channel for LTE and LTE-Advanced". 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142137.

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36

Helvik, Vilde Aspen. "Oslo Food Lab". Thesis, Norges teknisk-naturvitenskapelige universitet, Fakultet for arkitektur og billedkunst, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-17609.

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37

Navrátil, Petr. "Modely systému LTE". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-219984.

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Master’s thesis is focused on part of mobile network named LTE. Project is analyzes the LTE physical layer, which is divided into four basic parts: Physical channels and modulation, Multiplexing and channel coding, Physical layer procedures, Physical layer measurements. Every part is described by actual 3GPP standard [1]. To understand the problem is expected a reader basic knowledge of OFDM systems, which the LTE system uses. The next part of this master’s thesis is dedicated to mathematic model physical layer of system LTE, created by program Matlab. This model is designed to measure errors in data transmission.

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38

Broderick, Jane Tingle, Maura Bishop, B. Huber e L. Barrett. "Reggio Materials Lab". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/4223.

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39

Ekström, Angela, e Åsa Gustavsson. "LTG- metodens betydelse". Thesis, Malmö högskola, Lärarutbildningen (LUT), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-27661.

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LTG- metodens betydelse -Sex lärares syn på sitt arbete med läs- och skrivutveckling i skolår 1, ur ett LTG- perspektivAngela Ekström och Åsa GustavssonVi har gjort en kvalitativ undersökning där datainsamling har skett genom intervjuer. Problemområdet har varit att ta reda på hur sex lärare ser på sitt arbete med läs- och skrivutveckling i skolår 1, ur ett LTG- perspektiv (läsning på talets grund). Vi tycker att det finns outforskade luckor inom läs- och skrivutvecklingsområdet, gällande lärarperspektivet. Enligt vår mening har lärare blivit bortglömda då koncentrationen mest riktats på eleverna. Med denna undersökning vill vi bidra till kunskapsutveckling när det gäller blivande lärares kompetens inom läs- och skrivutveckling. Syftet är att erhålla vidare kunskap samt skapa en djupare förståelse för hur läs- och skrivutveckling kan ske i praktiken på olika sätt, med fokus på LTG- metoden. Våra problemformuleringar var: Hur ser de intervjuade lärarna på sitt arbetssätt med läs- och skrivutveckling i skolår1 och varför väljer de att arbeta så? Vilken betydelse och roll har LTG- metoden för de intervjuade lärarnas sätt att arbeta med läs- och skrivutveckling i skolår 1? Undersökningens genomförande har baserats på intervjuer och litteraturstudier. De sex intervjuade lärarna använder sig av LTG- metoden i sin undervisning, endast en av dem använder enbart denna metod. De övriga anser att LTG- metoden bör kompletteras med ljudningsmetoden. Valet av metod är inte avgörande, istället handlar det om lärares förhållningssätt till eleverna och att läraren tror på sitt arbetssätt med läs- och skrivutveckling.
AbstractThe importance of LTG- method- Six teachers´ views on their work with reading- and writing development skills in school year 1, from an LTG-perspectiveAngela Ekström and Åsa GustavssonWe have done a survey were our datacollection has been made through interviews. We wanted to know six teachers´ views on their work with reading- and writing development skills in school year 1, from an LTG- perspective (reading on the ground of speaking). With this survey we want to accomplish development of knowledge for students who wants to become teachers. Our main purpose is to gain more knowledge and create a deeper understanding for how reading- and writing development works in real life in different ways, with focus on LTG. One of our conclusions is that it’s not a question of choosing a method, instead it’s all about teachers attitudes and their believes in their work with reading- and writing development.

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40

Fernandes, Hugo Emanuel Mesquita. "Management consulting lab". Master's thesis, NSBE - UNL, 2011. http://hdl.handle.net/10362/10073.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
The purpose of this study was to investigate the exports generated in the geographical area under the management of ANA. Since the company have been increasing, and is not aware how they have been evolving. The analysis was done through an analytical overview over the company and all the activities that occur in the geographical area. Then, interviews were conducted to identify passengers’ major differences among the Portuguese airports. Based on all of the information were designed out-of-the box ideas to increase the level of exports.

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41

Sharma, Vivek. "Development of Control Lab Interface for Data Acquisition using Lab VIEW". Thesis, KTH, Reglerteknik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-106250.

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A lab named ‘System Identification Lab’ is a compulsory part of the course ‘Modeling of Dynamical System’ given by School of Electrical Engineering, Automatic Control at KTH. System identification is an experimental method to derive a mathematical model from the input and the output data. The apparatus used in the lab is a fan and a hinged rectangular plate. Both fan and plate are mounted on aslide. The idea of this lab is to collect the input and output data from this process. The input data is theDC voltage sent to the fan and the output is the angular displacement of the plate due to air stream from the fan. This data is then used to derive a linear model by applying different theoretical methods. The main focus of this thesis work has been to design a user interface for this lab, and implement it in LabVIEW, which is an easy to use, integrated graphical environment with built-in compatibility across a broad range of data acquisition and control hardware devices. In short, the interface first lets the user choose the sampling time and then one can choose between different input signals. The input and output signals are displayed as plots on the screen and can also be saved to a file. A second, similar interface has also been implemented, where the process is replaced by a simulation model. The simulation model is based on an identified linear model with some added disturbances and non-linear effects. The idea with the simulation model is that the ‘System Identification Lab’ then can be done without using the lab process. This report also includes an introduction to system identification and a discussion about how to choose appropriate input signals for an identification experiment. These methods are used to derive the simulation model and in order to understand the lab process better, some step responses are done and the process is also modeled from physical principles.

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SIEBRA, Gilca Bezerra Alves. "Cognição, linguangens e estereótipos acerca das pessoas deprimidas: estudo em três categorias profissionais". Universidade Federal de Pernambuco, 2012. https://repositorio.ufpe.br/handle/123456789/12780.

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Submitted by João Arthur Martins (joao.arthur@ufpe.br) on 2015-04-08T18:30:21Z No. of bitstreams: 2 Tese final.pdf: 3978208 bytes, checksum: cc7d7e00595a7450b2c9fbbe3928f985 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5)
Made available in DSpace on 2015-04-08T18:30:21Z (GMT). No. of bitstreams: 2 Tese final.pdf: 3978208 bytes, checksum: cc7d7e00595a7450b2c9fbbe3928f985 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012-02-14
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Esta tese trata do estudo de prováveis estereótipos quanto a pessoas deprimidas na produção linguística de três categorias: profissionais da área de Saúde, professores de Línguas e outros profissionais. Para tanto, fez-se uma revisão do que seriam linguagem e estereótipos – e sua neurobiologia –, a fim de se estabelecer sua interface. Foi feita uma revisita aos conceitos de crença, categorização social e Modelo de Categoria Linguística, entre outros, e seus pressupostos teóricos. Também foram abordados alguns indícios do que seriam afetividade e depressão, e seus impactos no cotidiano do indivíduo. Discutiu-se a existência inequívoca de estereótipos em produções linguísticas e o que eles revelam, bem como suas possíveis influências no sujeito – produtor e alvo do discurso – exposto a tais estereótipos, em especial naqueles que sofrem de depressão. Foi realizada uma pesquisa com profissionais da área de Saúde (em geral e Mental), professores de Línguas (Português e Inglês) e profissionais de outras áreas (de níveis médio e superior) com o intuito de verificar a possível diferença na ocorrência de vieses linguísticos referentes aos deprimidos e aos não deprimidos (LEB), o que efetivamente se comprovou na codificação linguística mais positiva dos profissionais de Saúde quanto aos deprimidos, apontando ainda para um olhar mais humano desse profissional, indiferente ao fato de se ser ou não deprimido (LEB), ou de se pertencer ou não à sua categoria profissional (LIB). O viés linguístico intergrupal (LIB) nas três categorias investigadas se evidenciou na forma como cada categoria codificou a si própria mais favoravelmente, de acordo com os pressupostos teóricos. Espera-se que este estudo contribua para dirigir um olhar mais atento sobre comportamentos linguísticos baseados em estereótipos e suas possíveis implicações.

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Serra, Pagès Albert. "Link level performance evaluation and link abstraction for LTE/LTE-advanced downlink". Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/392609.

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Els objectius principals d'aquesta tesis són l'avaluació del rendiment a nivell d'enllaç i l'estudi de l'abstracció de l'enllaç pel LTE/LTE-Advanced DL. S’ha desenvolupat un simulador del nivell d'enllaç E-UTRA DL basat en la tecnologia MIMO-OFDM. Es simulen els errors d'estimació de canal amb un model d'error de soroll additiu Gaussià anomenat CEEM. El resultat d'aquest simulador serveix per avaluar el rendiment a nivell d'enllaç del LTE/LTE-Advanced DL en diferents entorns . La idea bàsica dels mètodes d'abstracció de l'enllaç és mapejar el vector de SNRs de les subportadores a un valor escalar, l'anomenada ESNR, la qual és usada per a predir la BLER. Proposem un innovador mètode d'abstracció de l'enllaç que pot predir la BLER amb bona precisió en esvaïments multicamí i que inclouen els efectes de les retransmissions HARQ. El mètode proposat es basa amb l'estimació de la informació mútua entre els bits transmesos i els LLRs rebuts.
The main objectives of this dissertation are the evaluation of the link level performance and the study of link abstraction for LTE/LTE-Advanced DL. An E-UTRA DL link level simulator has been developed based on MIMO-OFDM technology. We simulate channel estimation errors by a Gaussian additive noise error model called CEEM. The result of this simulator serves to evaluate the MIMO-OFDM LTE/LTE-Advanced DL link level performance in different environments. The basic idea of link abstraction methods is to map the vector of the subcarrier SNRs to a single scalar, the ESNR, which is then used to predict the BLER. We propose a novel link abstraction method that can predict the BLER with good accuracy in multipath fading and including the effects of HARQ retransmissions. The proposed method is based on estimating the mutual information between the transmitted bits and the received LLRs.

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Schoerner, Jacob, e Miguel Müller. "Automated Assignment of Lab Assistants to Student Presentations at KTH Lab Sessions". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229694.

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The authors study the case of lab presentations at KTH. Currently, lab assistants follow the First In First Out principle when deciding what student presentation to visit first. The authors study whether the Shortest Job Next discipline can give a significant advantage in presentation throughput. They create a simulation of a lab session, and simulate sessions with both SJN and FIFO, and varying values of time per presentation, number of assistants and number of lab rooms in the session. It is shown that Shortest Job Next gives a consistently higher number of presentations, but also on average a longer maximum waiting time. The effect on number of handled presentations is the highest when the time per presentation is low and the number of rooms is high.
Författarna studerar labbpresentationer vid KTH. I nuläget baserar sig labbassistenter på First In First Out-principen när de bestämmer vilken ordning de ska besöka de olika studentgrupperna som har markerat sig som redo att presentera. Författarna undersöker huruvida Shortest Job Next-principen kan ge ett betydande övertag i antal presentationer per tidsenhet. De skapar en simulation av ett labbtillfälle och testar simulationen mot både FIFO och SJN, under ett antal olika värden på tid per presentation, antal tillgängliga övningsassistenter och antal rum i labbsessionen. Det visar sig att Shortest Job Next ger ett konsekvent högre antal presentationer per tidsenhet, men att den också medför en risk att vissa grupper får vänta väldigt länge på att presentera. Effekten på antal avklarade presentationer är som störst när tiden per presentation är låg och antalet rum är stort.

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Favraud, Romain. "Réseau d'accès radio LTE/LTE-A autonome et maillé pour environnements contraints". Electronic Thesis or Diss., Paris, ENST, 2017. http://www.theses.fr/2017ENST0058.

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Les systèmes de communication militaires s'améliorent aujourd'hui lentement comparés aux systèmes civils. les systèmes de communications pour les réseaux de sécurité publique évoluent suite à l'émergence de la technologie long term evolution (LTE). Cependant, le LTE a initialement été conçu pour les réseaux cellulaires commerciaux. Dans cette thèse, nous développons une solution complète permettant de répondre aux cas d'utilisation contraints auxquels font face les organisations de sécurité publique et militaires. Cette solution permet, sur une seule bande de fréquence LTE, le maillage sans fil de stations de base mobiles tout en maintenant l'accès au réseau de terminaux mobiles standards. Nous dérivons les exigences fonctionnelles d'un système de communication à partir des cas d'utilisation des autorités militaires et de sécurité publique. Les contraintes dues aux environnements spécifiques d'utilisation mènent au choix du LTE comme technologie radio. Nous présentons une infrastructure réseau qui permet la création de réseaux maillés LTE multi-bonds qui s'appuie sur une nouvelle station de base autonome et mobile permettant le maillage intra-bande : le e2nb. Nous détaillons cette architecture, nous évaluons la coordination entre stations de base et nous proposons un algorithme d'ordonnancement de ressources radio afin de satisfaire des exigences de qualité de service. Nous implémentons et évaluons l'interface sans fil sur la plateforme de radio logicielle openairinterface. Nous évaluons l'algorithme d'ordonnancement sur différentes topologies avec différents flux. Finalement, nous résumons les incertitudes restantes concernant les déploiements sur le terrain
Military communication systems are nowadays improving slowly compared to commercial systems. In parallel, public safety (ps) communication systems are changing due to emergence of long term evolution (LTE) as a mature solution. However, LTE is initially designed for commercial cellular network and need to be evolved to tackle the requirements of ps use cases. In this thesis, we develop a complete solution to address constrained ps and military use-cases allowing to wirelessly mesh mobile network nodes and to provide access to standard user equipments while only requiring a single radio band. Starting from ps and military use cases, we present the potential scenarios and derive functional requirements for future wireless systems. The constraints applying to these systems lead to the selection of LTE as the radio access technology. We detail the challenges faced by a LTE solution given the state of the art. We present a novel network infrastructure architecture that enables multi-hop LTE mesh networking for autonomous base stations via in-band self-backhauling relying on a new base station: the e2nb. We detail the building blocks of the architecture, we investigate the coordination and orchestration functionality and propose a cross layer hierarchical resource scheduling algorithm in order to efficiently meet quality of service requirements for real-time traffic while maximizing the throughput for elastic flows. We evaluate the self-backhauling interface using open air interface and then evaluate our resource scheduling algorithm in various network topologies and traffic flows. Finally, we summarize the remaining uncertainties concerning real-field deployments

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Zhou, Kaijie. "Technique d'accès pour la communication machine-à-machine dans LTE/LTE-A". Thesis, Paris, ENST, 2013. http://www.theses.fr/2013ENST0076/document.

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Les communications de type machine-à-machine M2M sont considérées comme des formes de communication de données qui ne requièrent pas nécessairement d'interaction humaine. Cependant, ce type de communication n'est pas efficace dans les réseaux cellulaires, en raison de leurs caractéristiques spécifiques, telles que. L'objectif de cette thèse est de proposer des mécanismes et d'optimiser les techniques de la couche d'accès radio LTE pour les communications M2M. Pour l'accès au canal de liaison montante, nous proposons deux méthodes afin d'améliorer la performance d'accès aléatoire en terme de latence et de consommation énergétique: une méthode d'agrégation de paquets et une autre de transmission multiple pendant l'intervalle de temps de transmission. Afin de réduire encore plus le temps de latence de liaison montante et permettre une connexion d'un grand nombre de machines au réseau, nous proposons une nouvelle méthode d'accès basée sur la contention CBA pour éviter d'une part la signalisation redondante pour accéder au canal et d'autre part la latence de l'ordonnanceur. Pour la réception de liaison descendante, nous proposons deux méthodes pour analyser les performances du mécanisme de réception discontinu DRX pour les applications M2M: la première se base sur une distribution de Poisson, la suivante sur une distribution Pareto pour le trafic sporadique. Avec les modèles proposés, le facteur d'économie d’énergie et la latence pour transiter du mode sommeil au mode actif peuvent être estimés avec précision pour un choix donné de paramètres DRX, permettant ainsi de sélectionner ceux permettant d'atteindre le compromis optimal
Machine type communications is seen as a form of data communication, among devices and/or from devices to a set of servers, that do not necessarily require human interaction. However, it is challenging to accommodate MTC in LTE as a result of its specific characteristics and requirements. The aim of this thesis is to propose mechanisms and optimize the access layer techniques for MTC in LTE. For uplink access, we propose two methods to improve the performance of random access in terms of latency: a packet aggregation method and a Transmission Time Interval bundling scheme. To further reduce the uplink latency and enable massive number of connected device, we propose a new contention based access method (CBA) to bypass both the redundant signaling in the random access procedure and also the latency of regular scheduling. For downlink reception, we propose two methods to analyze the performance of discontinuous reception DRX mode for MTC applications: the first with the Poisson distribution and the second with the Pareto distribution for sporadic traffic. With the proposed models, the power saving factor and wake up latency can be accurately estimated for a given choice of DRX parameters, thus allowing to select the ones presenting the optimal tradeoff

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47

CANDELIER, LAURENT. "Isolement et caracterisation des particules lipoproteiques plasmatiques lpb, lpb : e, lpb c-iii et lpb : c-iii : e. mise au point et utilisation d'une methode de chromatographie d'immunoaffinite sequentielle". Lille 2, 1989. http://www.theses.fr/1989LIL2P259.

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48

Miller, Roxanne M. "Pharmaceutical and Natural (Exercise) Mechanisms to Mitigate the Negative Impact of PTSD and Chronic Stress on Synaptic Plasticity and Memory". BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/7242.

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Synapses can be altered due to experiences in a process called synaptic plasticity, which causes memory formations. Synapses can be strengthened through methods known as long-term potentiation (LTP) or weakened through long-term depression (LTD). Stresses can cause changes by altering synapses through either LTP or LTD. Rats were used to study the effects of post-traumatic stress disorder (PTSD)-like symptoms and a prophylactic treatment using pharmaceuticals. The first model used was the single prolonged stress (SPS) with two weeks of chronic light, which was not as effective for causing changes in synaptic plasticity. The second model, seven days of social defeat (SD) with two weeks of chronic light was more effective at inducing PTSD-like behavior symptoms and causing changes in LTP levels in the ventral hippocampus, amygdala, and prefrontal cortex between stressed and non-stressed rats. For the prophylactic treatment, propranolol and mifepristone were administered one week prior to and throughout the two weeks of the social defeat protocol. The drugs were able to prevent the changes due to stress on LTP in the three aforementioned brain regions, but did not change the anxious behavior of the rats. An enzyme-linked immunosorbent assay (ELISA) was used to determine corticosterone and norepinephrine levels between the different groups of rats. No significant differences were detected between SD and control rats, but SD injected rats were different from controls indicating that the injections were causing added stress. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) was used to detect changes in the adrenergic, corticoid, AMPA, and NMDA receptors. There were a few significant changes to some of the targets indicating that the stress protocol and drugs were having an effect on the mRNA expression. Propranolol and mifepristone could possibly be used as a prophylactic treatment for traumatic stress. In a separate study, techniques were used to determine the negative effects chronic stress (non-PTSD-like) has on synaptic plasticity in the dorsal hippocampus and to show how exercise was able to mitigate some of those negative stress effects. Electrophysiology showed differences in LTP between four groups of mice: sedentary no stress (SNS), sedentary with stress (SWS), exercise with stress (EWS), and exercise no stress (ENS). SWS had the lowest amount of LTP, whereas ENS had the highest. SNS and EWS had similar levels of LTP, which were in between the SWS and ENS groups. Corticosterone blood levels measured by an ELISA showed significant increases in the stressed groups compared to the non-stressed groups. The radial arm maze showed that both groups of exercise mice made fewer reference memory errors the second week of testing compared to the sedentary groups. RT-qPCR determined that brain-derived neurotrophic factor (BDNF) and corticoid and dopamine 5 receptors were likely causing some of the memory changes.

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49

Linnerud, Ådne Solhaug. "Lab-oppsett for proteseforskning". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18593.

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Institutt for Teknisk Kybernetikk(ITK) ved NTNU har et programvarebibliotek for styring av proteser. Dette biblioteket består av et mønstergjenkjenningssystem som kan brukes til å styre en robothånd. Mønstergjenkjenning gir protesebrukeren mulighet til å styre en protese, men uten den grad av kontroll som er ønsket. Derfor er det i denne oppgaven blitt implementert et proporsjonalt styringssystem som skal gjøre at brukeren kan kontrollere en protese bedre. For å trene opp et slikt system er det utviklet metoder som skal brukes sammen med proteseguidet trening. Det er også utviklet treningssett som brukes for å lagre referanseverdier. For å vise at dette kan brukes på proteser, ble kontroll av en protese fra Motion Control implementert inn i ITKs bibliotek. Resultatene indikerer at dette fungerer bra, men at det å kontrollere flere frihetsgrader simultant er vanskelig. Derfor må det utvikles nye treningssett som kan forbedre kontroll av flere frihetsgrader simultant.

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50

Hill, Edward George. "Non-LTE plasma spectroscopy". Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542941.

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