Dissertationen: „Lenght“

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Levold, Pål. „Viscous Flow Around Finite Lenght Circular Cylinder“. Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18641.

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Viscous flow around circular cylinders is a classical research topic in fluid dynamics with a vast amount of practical applications in the field of offshore marine technology. In the flow around cylinders of finite length, complex wake behaviours and coherent structures occur even at relatively low Reynolds numbers. An understanding of the nature and dynamics behind such behaviour could form a basis for improved designs and innovative solutions for offshore and subsea constructions.In the present study, flow around long finite cylinders at Re = 100 is investigated numerically using the incompressible Navier-Stokes Equations solver MGLET. To study the isolated flow near the free end, a cylinder with aspect ratio L/D = 50 is chosen. The flow over the free end gives rise to a wake consisting of two vortex shedding cells with different shedding frequencies; one small near the free end and one larger in the central region of the span. It is found that each vortex shed in the end cell bends horizontally and connects with the upstream vortex shed from the opposite side of the cylinder. The horizontal vortex shedding is found to give rise to a pair of trailing vortices in the time averaged flow.When a vortex is shed with a large phase difference between the two cells, the vortex is split and connects with other surrounding vortices. This phenomena is commonly referred to as vortex dislocations and occurs with the beat frequency, i.e. the difference between the two vortex shedding frequencies. It is found that this frequency can be detected in time histories of $u$ in the wake at the spanwise centre.A second configuration, consisting of a wall mounted cylinder with aspect ratio L/D = 25 is simulated in order to study the effect of introducing a no-slip surface. The effect on the end cell is found to be minimal, while the central cell shedding frequency is reduced. Comparisons with published data on a cylinder with aspect ratio L/D = 25 and two free ends shows that both the reduction of aspect ratio and the introduction of the no-slip boundary condition contributes to the reduced shedding frequency.

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Gonzalez, Camelo Sandra Patricia. „BCS superfluid Fermi systems with large scattering lenght“. Doctoral thesis, SISSA, 2007. http://hdl.handle.net/20.500.11767/3931.

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Faggion, Mauro <1976&gt. „L'evoluzione dell'arm's lenght principle nella dimensione internazionale e comunitaria“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amsdottorato.unibo.it/9122/1/tesi%20definitiva_17_06_2019%20%283%29.pdf.

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Gunneriusson, Olof. „Method for determining phasedistribution and characteristic lenghts in cBN-composite materials“. Thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-206276.

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An image analysis method has been developed for Sandvik to determine phasecompositions and characteristic length of the binding phase in cubic Boron Nitride(cBN)-composites with low contents of cBN (35-75%).The method consists of taking pictures with a Scanning Electron Microscope,gathering elemental data with X-ray Diffraction (XRD) as well as Energy-dispersiveX-ray Spectroscopy (EDS) and finally using a Matlab program developed for this workto calculate phase compositions and statistical data from the characteristic length ofthe binding phase.Using these methods four different phases were identified in the samples: Blackparticles, most likely made of cBN. A dark gray phase around the black particles, thatconsists of Al-compounds. A light grey binding phase, consisting of TiN or Ti(C,N).Finally there were small traces of white particles which were identified as a product ofabrasive action on cermet milling bodies added during the milling.Mean value, standard deviation and median of the characteristic length of the bindingphase was calculated. For all samples the median value was consistent, sometimeseven being identical for the analyzed sites. This indicates that the binding phase wasevenly distributed across almost all samples.

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CONTE, GRAZIANA. „No-go theorems for quantum information theory and computational logic for variable lenght quantum registers“. Doctoral thesis, Università degli Studi di Milano, 2008. http://hdl.handle.net/2434/59837.

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In this dissertation we take in account the possibility to face the notion of quantum information from two different points of view: meanwhile in the first part we develop a concrete approach to the notion of quantum information, in the second part we proceed to a more abstract approach. The firts part explores what quantum mechanics forbids to do with information encoded in states of quantum systems. Many of the results of researches about what we can and what we can t do with the information encoded in quantum states are known as no-go theorems; in this dissertation we explore new limitations on the possibility to manipulate quantum information revealing that many easy tasks for classical information are impossible when the information is encoded in quantum states. As result of our analysis it arises that the nature of information encoded in quantum states restricts in a very structured way the possible manipulations or exact behaviour of the operations on the information itself. In the second part of dissertation we concentrate on logic-algebraich approach to quantum information. We relax the condition of a quantum circuit constitued by a fixed number of particles and we take in account a quantum system of variable and undeterminate number of particles. This approach is developed in the mathematical framework of Fock space which allows a more flexible treatment of information encoded in quantum register of variable lenght. As consequence, we proceed towards a possible logic-algebraic formalization of the behaviour of quantum information encoded in variable lenght registers during a computational process.

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Ogunjobi, Taiwo A. „Computational Study of Ring-Cusp Magnet Configurations that Provide Maximum Electron Confinement“. Wright State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=wright1166226698.

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Lemos, Carla Alexandra Ribeiro Cerqueira de. „Aspetos estruturais e funcionais do complexo telómero/telomerase“. Master's thesis, [s.n.], 2015. http://hdl.handle.net/10284/5320.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas
Os telómeros são estruturas nucleoproteicas heterocromáticas de comprimento variável presentes nas extremidades dos cromossomas. Os telómeros, conjuntamente com a telomerase, permitem ultrapassar a limitação replicativa dos segmentos terminais de DNA que se verifica na maioria das células humanas somáticas e que está associada à diminuição do comprimento do DNA telomérico em cada divisão celular. As estruturas cromossómicas teloméricas são constituídas por longas extensões de repetições hexaméricas 5’-TTAGGG-3’ de cadeia dupla e por um complexo proteico específico designado por shelterin. As sua principais funções incluem a proteção das extremidades dos cromossomas contra uma eventual fusão ou degradação prematura da molécula de DNA, regulação da síntese de DNA telomérico e regulação/manutenção do comprimento do telómero. Os telómeros de mamíferos são transcritos por ação da RNA polimerase II a partir de vários loci subteloméricos e as moléculas de RNA produzidas são constituídas por um número variável de repetições da sequência 5’-UUAGGG-3’. A sua associação ao telómero ocorre através da formação do segmento híbrido RNA-DNA ou da interação de ribonucleoproteínas específicas. Apesar da função deste transcripto ainda não estar completamente estabelecida, várias evidências sugerem a sua participação no processo de regulação do comprimento dos telómeros através de vários mecanismos: inibição da atividade da telomerase, ativação de exonucleases, regulação do nível de eucromatina e/ou atuação como fator de proteção. A telomerase é um complexo ribonucleoproteico constituído por uma parte central, que inclui a subunidade catalítica com atividade de transcriptase reversa, e por RNA, que representa a sequência molde para a síntese do DNA telomérico. A sua biossíntese, maturação e atividade catalítica estão relativamente bem caracterizadas. A base molecular para a regulação da atividade da telomerase é complexa e envolve vários níveis de controlo, principalmente transcripcional. No entanto, existem diversas evidências que sugerem que a enzima é também submetida a processos de controlo pós-trancripcional e pós-traducional. Dada a relação observada entre o comprimento do DNA telomérico e processos celulares aparentemente antagónicos tais como o envelhecimento e a tumorigénese, pretende-se com o presente trabalho de revisão bibliográfica caracterizar os principais aspetos estruturais e funcionais do complexo telómero/telomerase e compreender o seu papel na manutenção do comprimento dos telómeros. Adicionalmente, é explorada a importância do conhecimento sobre a biologia molecular e celular deste complexo para a identificação e o desenvolvimento de novas abordagens para a prevenção do envelhecimento ou do cancro.
Telomeres are heterochromatic nucleoproteicas structures of varying length present at the ends of chromosomes. Telomeres, together with the telomerase, allow to overcome the limitation imposed by terminal DNA segments of chromosome to the semi-conservative DNA replication of most human somatic cells, which is associated with the decreased length of telomeric DNA in each cell division. The telomeric cromosomal structures are composed of long extensions of double stranded hexameric repetitions 5’-TTAGGG-3’ and a specific proteinaceous complex termed as shelterin. The main functions of this nucleoprotein complex include the protection of the chromosomal endings against an eventual fusion or premature DNA degradation, regulation of the telomeric DNA synthesis and regulation/maintenance of the telomere length. The telomeres of mammals are transcribed through the action of RNA polymerase II from several subtelomeric loci. The produced RNA molecules are composed of a variable number of 5’-UUAGGG-3’ sequence repetitions. The association of this RNA molecule with telomeres occurs through the formation of a RNA-DNA hybrid or interation of ribonucleoproteins. Although the function of this transcript molecule is not completely established, yet, several evidences suggest its participation in the process of regulation of telomere lenght through several mechanisms: telomerase activity inhibition, exonucleases activation, regulation of the chromatin level and/or protection factor. The telomerase is a ribonucleoprotein complex formed by a central core including the catalytic subunit with activity of reverse transcriptase and RNA, which represents the template sequence used in the telomeric DNA elongation. The biosynthesis, maturation and catalytic activity of telomerase are relatively well characterised. The molecular basis of telomerase activity regulation is complex and involve several levels of control, mainly the transcriptional level. Nonetheless, several evidences suggest that enzyme is also subjected to pos-transcriptional and pos-tradutional regulation. Given the relation observed between the length of telomeric DNA and the apparently antagonic processes of aging or tumorigenesis, the present work of bibliographic review aims to characterise the main structural and functional aspects of the complex telomere/telomerase and to understand its role in the maintenance of telomere length. Additionally, it also explores the importance of the knowledge on the molecular and cell biology of this complex to the identification and development of novel approaches to prevent aging or cancer.

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Gual, Frau Josep. „Efecto de la microvaricocelectomía y el tratamiento antioxidante oral en el adn espermático en pacientes infértiles con varicocele“. Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/669516.

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Introducció El varicocele és una de las majors causes d'infertilidad masculina. El tractament quirúrgic del varicocele està indicat en pacients amb infertilitat i varicocele clínic o palpable. La microcirurgía del varicocele ha demostrat ser la millor tècnica per a la seva reparació. El varicocele grau I o subclínic, al què no es recomana el tractament quirúrgic, també pot ser causa d'infertilidad. El tractament antioxidant ha demostrat millories a la qualitat seminal de pacients infèrtils, però no hiha dades del seu efecte en pacients amb varicocele. Les espècies reactives d'xigen que es generen en augment en pacients amb varicocele, poden danyar l'ADN espermàtic, principalment a través de modificacions a la guanina. Al nostre grup, vam postular què l'efecte de dany a l'ADN podia ser més intens als telòmers, donat que els telmeros són rics en guanina, fet que podroa comprometre la fertilitat. Hipòtesi i Objectius Coneixent les anteriors afirmacions, s'ha intentat analitzar per una banda l'efecto de la microvaricocelectomia sobre la longitut telomèrica i fragmentació de l'ADN espermàtic, així com el seu efecte al seminograma i, per una altra banda, en aquells pacients amb varicocele subclínic, s'ha intentat comprovar l'efecto del tractament antioxidant tant al seminograma como a la fragmentació de l'ADN espermàtico. Material y Mètodes S'han incluido a l'estudi 12 donants de semen fèrtils i 40 pacients amb varicocele associat a infertilitat i s'han dividit en 2 grups. Grup 1: 20 pacients amb varicocele clínic, als quals s'ha analitzat abans i 9 mesos després del tractament quirúrgic mitjançant microvaricocelectomia, els valors del seminograma, la fragmentació de simple i doble cadena i la longitut telomèrica de l'ADN espermàtic. Grup 2: 20 pacients amb varicocele subclínic, als quals s'ha analitzat abans i 3 mesos després del tractament antioxidant oral mitjançant un complexe multivitamínic, els valors del seminograma i la fragmentació d'ADN espermàtic. Resultats En comparació a donants fèrtils, el varicocele no té una reducció significativa de la longitut telomèrica. Respecte a la microvaricocelectomia, tampoc ha demostrat canvis en dita longitud. No obstant això, si s'han observat canvis estadísticament significatius en quant als valors del seminograma i de la fragmentació d'DN espermàtic, tant de simple com de doble cadena. En quant al tractament antioxidant en els pacients amb varicocele subclínic, ha demostrat una reducció significativa de la fragmentació de l'espermàtic, mentre queal seminograma, només es van observar canvis a favor del tractament al nombre total de espermatozous, sense que es veieren alterats la resta de valors del seminograma. Conclusions En base als nostres resultats, podems afirmar què a la nostra sèrie no hem trobat un efecte del varicocele i del seu tractament quirúrgic sobre la longitut telomèrica de l’ADN espermàtic. Si que hem confirmat la milloria a les xifres de fragmentació de l'ADN espermàtic de simple i doble cadena i millories al seminograma gràcies al tractament. Per una altra banda, les dades sugereixen què la integritat de l'ADN espermàtic al varicocele grau I millora amb el tractament antioxidant oral."
Introducción El varicocele es una de las mayores causas de infertilidad masculina. El tratamiento quirúrgico del varicocele está indicado en pacientes con infertilidad y varicocele clínico o palpable. La microcirugía del varicocele ha demostrado ser la mejor técnica para su reparación. El varicocele grado I o subclínico, en el que no se recomienda el tratamiento quirúrgico, también puede ser causa de infertilidad. El tratamiento antioxidante ha demostrado mejorías en la calidad seminal de pacientes infértiles, pero no hay datos de su efecto en pacientes con varicocele. Las especies reactivas de oxígeno que se generan en aumento en pacientes con varicocele, pueden dañar el ADN espermático, principalmente a través de modificaciones en la guanina. En nuestro grupo, postulamos que el efecto de daño en el ADN podía ser más intenso en los telómeros, dado que los telómeros son ricos en guanina, hecho que podría comprometer la fertilidad. Hipótesis y Objetivos Conociendo las anteriores afirmaciones, se ha intentado analizar por un lado el efecto de la microvaricocelectomía sobre la longitud telomérica y fragmentación del ADN espermático, así como su efecto el seminograma; y por otro lado, en aquellos pacientes con varicocele subclínico, se ha intentado comprobar el efecto del tratamiento antioxidante tanto en el seminograma como en la fragmentación del ADN espermático. Material y Métodos Se han incluido en el estudio 12 donantes de semen fértiles y 40 pacientes con varicocele asociado a infertilidad y se han dividido en 2 grupos. Grupo 1: 20 pacientes con varicocele clínico, en los cuales se ha analizado antes y 9 meses después del tratamiento quirúrgico mediante microvaricocelectomía, los valores del seminograma, la fragmentación de simple y doble cadena y la longitud telomérica del ADN espermático. Grupo 2: 20 pacientes con varicocele subclínico, en los cuales se ha analizado antes y 3 meses después del tratamiento antioxidante oral mediante un complejo multivitamínico, los valores del seminograma y la fragmentación de ADN espermático. Resultados En comparación a donantes fértiles, el varicocele no tiene una reducción significativa de la longitud telomérica. Respecto a la microvaricocelectomía, tampoco ha demostrado cambios en dicha longitud. Sin embargo, sí se han observado cambios estadísticamente significativos en cuanto a los valores del seminograma y de la fragmentación de ADN espermático, tanto de simple como de doble cadena. En cuanto al tratamiento antioxidante en los pacientes con varicocele subclínico, ha demostrado una reducción significativa de la fragmentación del ADN espermático, mientras que en el seminograma, solamente se observaron cambios a favor del tratamiento en el número total de espermatozoides, sin que se vieran alterados el resto de valores del seminograma. Conclusiones En base a nuestros resultados, podemos afirmar que en nuestra serie no hemos encontrado un efecto del varicocele y de su tratamiento quirúrgico sobre la longitud telomérica del ADN espermático. Sí que hemos confirmado la mejoría en las cifras de fragmentación del ADN espermático de simple y doble cadena y mejorías en el seminograma gracias al tratamiento. Por otro lado, los datos sugieren que la integridad del ADN espermático en el varicocele grado I mejora con el tratamiento antioxidante oral.
Introduction Varicocele is one of the main causes of male infertility. The surgical treatment of varicocele is indicated for patients with infertility in combination with clinical or palpable varicocele. Mycrosurgurgical varicocelectomy has demonstrated to be the best procedure for its repair. Grade I varicocele o subclinical, in which it is not recommended this surgical treatment, could be as well an infertility cause. Antioxidant treatment has demonstrated seminal quality improvements, but there is no prior data to investigate the effect on varicocele patients. Reactive oxygen species, that are highly generated in varicocele patients, can damage sperm DNA, principally due to guanine modifications. In our group, we thought that the effect of DNA damage could be more intense because the telomeres are rich in guanine, fact that could also compromise fertility. Hypothesis and Objectives In the view of the above, in one hand, we tried to analyze the effect of microvaricocelectomy to the telomere length and sperm DNA fragmentation, and its effect on seminal parameters. On the other hand, in subclinical varicocele patients, we tried to assess the effect of antioxidant treatment in seminal parameters and in sperm DNA fragmentation. Material and Methods For this purpose, 12 fertile donors and 40 infertile varicocele patients were included in the study and divided in two groups: Group 1: 20 clinical varicocele patients, in which we analyzed, before and 9 months after microvaricocelectomy surgical treatment, seminal parameters, sperm simple and double-strand DNA fragmentation and telomere length. Group 2: 20 subclinical varicocele patients, in which we analyzed, before and after 3 months of oral antioxidant treatment with a multivitamin complex, seminal parameters and sperm DNA fragmentation. Results Comparing with fertile donors, varicocele had no effect on telomere length. Results showed that microsurgical varicocelectomy had no effect on telomere length before and after treatment. However, we observed significant statistical differences in seminal parameters and sperm simple and double DNA fragmentation. Referring to antioxidant treatment in subclinical varicocele patients, we demonstrated a significant reduction on sperm DNA fragmentation, whilst we only observed changes in total sperm count in favor to the treatment, without observing changes in the rest of seminal parameters. Conclusions On the basis of the findings, we are able to affirm that in our series we have not found an effect of varicocele and its surgical treatment over sperm ADN telomere length. We have confirmed improvements in sperm DNA simple and double strand fragmentation levels due to surgical treatment and improvements on seminal parameters. Moreover, data suggest that sperm DNA integrity, in varicocele grade I patients, improve with oral antioxidant treatment.

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Svensson, Cassandra. „An eye-tracking study on synonym replacement“. Thesis, Linköpings universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119380.

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As the amount of information increase, the need for automatic textsimplication also increase. There are some strategies for doing thatand this thesis has studied two basic synonym replacement strategies.The rst one is called word length and is about always choosinga shorter synonym if it is possible. The second one is called wordfrequency and is about always choosing a more frequent synonym if itis possible. Three dierent versions of them were tried. The rst onewas about just choosing the shortest or most frequent synonym. Thesecond was about only choosing a synonym if it was extremely shorteror more frequent. The last was about only choosing a synonym if itmet the requirements for being replaced and was on synonym level 5.Statistical analysis of the data revealed no signicant dierence. Butsmall trends showed that always choosing a more frequent synonymthat is of level 5 seemed to make the text a bit easier.

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Rojas, Thaís Cabrera Galvão. „Utilização de AFLP para estudos genéticos em Prochilodus argenteus (Pisces, Prochilodontidae)“. Universidade Federal de São Carlos, 2008. https://repositorio.ufscar.br/handle/ufscar/5448.

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Universidade Federal de Sao Carlos
Genetic studies have been performed for an endemic species from São Francisco River basin, Prochilodus argenteus, which has a great importance in the artisanal and subsistence fishing in the region. The linkage mapping and the genetic variability studies were made with AFLP (Amplified Fragment Length Polymorphism) dominants markers and with 189 specimens from a F1 cross, that was also used for restocking the upstream area from Três Marias hydroelectric dam. All the analyses were carried out with 15 primer pairs combinations and the linkage map was made using the pseudo-testcross mapping strategy. Forty six heterozygous marks were found for the genitors, with mendelian segregation of 1:1. The female genitor map had 3 linkage groups and the lenght of the analysed genome was 128,45 cM, the male genitor map had the same number of linkage groups and the total length of 192,67 cM. Common markers for both genitors, with mendelian segregation ratio of 3:1, served as bridge between the maps, for the construction of an integrated map. This map had 9 linkage groups, and the total map length was 442,08 cM. Additionally, the genetic variability was assessed and an expected heterozygosity mean was of 0,32082, with a Jaccard s similarity coefficient of 0,72564 + 0,00451. These preliminary values show that the cultured sample has a higher similarity coefficient than that obtained for the wild populations. Hence, the present results suggest that genetic studies and management restocking practices should be simultaneously performed for the maintenance of the genetic patrimony of this species at the São Francisco River basin. The results also showed that AFLP marks were suitable and effective to identify linkage marks in Prochilodus argenteus and for genetic variability studies in cultivar samples.
Estudos genéticos foram realizados em uma espécie endêmica da bacia do rio São Francisco, Prochilodus argenteus, a qual possui grande importância na pesca artesanal e de subsistência da região. Os estudos do mapa de ligação e de variabilidade genética foram realizados com o uso do marcador dominante AFLP (Polimorfismo de Comprimento de Fragmentos Amplificados) e com 189 indivíduos de um cruzamento F1, utilizado também para o repovoamento do rio São Francisco, à montante da barragem de Três Marias (MG). Todas as análises foram realizadas com 15 combinações de primers. Para a construção dos mapas de ligação foi utilizada a abordagem pseudocruzamento teste. Os primers utilizados geraram 46 marcas heterozigóticas para os genitores, com segregação mendeliana de 1:1. O mapa referente ao genitor feminino apresentou 3 grupos de ligação e o comprimento do genoma analisado foi de 128,45 cM, e o mapa do genitor masculino também consistiu em 3 grupos de ligação com comprimento total de 192,67 cM. Marcadores comuns aos dois genitores, com segregação mendeliana de 3:1, foram utilizados como pontes na integração dos mapas. O mapa integrado foi formado por 9 grupos de ligação, o que correspondeu a 442,08 cM de genoma analisado. Adicionalmente, a variabilidade genética foi estudada por meio da média da heterozigosidade esperada (He), a qual foi de 0,32082 e pela análise do coeficiente de similaridade de Jaccard, que foi igual a 0,72564 + 0,00451. Estes valores, ainda que preliminares, mostraram que essa amostragem cultivada possui o coeficiente de similaridade maior quando comparado com os de populações selvagens. Desta forma, sugere-se no presente trabalho que estudos genéticos devam ser realizados juntamente com a prática de repovoamento de rios, visando conservar o patrimônio genético desta espécie na bacia do São Francisco. Os resultados mostraram também que os marcadores AFLP foram adequados e eficientes para a identificação de marcas ligadas em Prochilodus argenteus e no estudo da variabilidade genética de amostras cultivadas.

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Šigutová, Petra. „Řešení dřevěných halových konstrukcí“. Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226804.

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The subject of my thesis is a static analysis of a different trusses of a great span length. The preface is devoted to the trusses their creation of plane models of a girder with the extent of 18 metres. The questions of construction´s joints are mainly solid. The conclusion is dedicated to the creation of the girder and joints´ formation.

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Santos, Gilmário Barbosa. „Modelagem 3D para a determinação do comprimento de arcos elétricos usando imagens estereoscópicas = 3D modeling for determination of lenght of electrical arcs using stereo images“. [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260991.

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Orientador: Maria Cristina Dias Tavares
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: O comprimento do arco elétrico é um parâmetro importante para a modelagem matem ática do arco elétrico. O perfil da variação do comprimento do arco atualmente é estimado pela análise da tensão medida entre os terminais do arco e da corrente do arco. Porém esses resultados não são conclusivos, pois não apresentam uma medição (escala métrica) do eixo-médio tridimensional do arco elétrico. Por outro lado, as imagens da evolução do arco podem fornecer informação suficiente à reconstrução do seu eixo tridimensional e à estimativa do comprimento do arco a cada instante, determinando uma curva de variação do comprimento. A principal contribuição deste trabalho, portanto, reside na obtenção da estimativa do comprimento do arco e, por conseguinte, do alongamento de arcos elétricos baseada na aplicação do modelo snake-3D na reconstrução tridimensional dos eixos longitudinais de arcos elétricos gerados artificialmente. Foram realizados diferentes experimentos para avaliar a proposta de aplicação da snake-3D. Inicialmente, algumas características geométricas dos arcos foram reproduzidas em curvas paramétricas cujas projeções, sobre seções de planos, formaram as sequências de pares de imagens e determinaram os conjuntos de casos experimentais. Em seguida os resultados obtidos através da aplicação da snake-3D foram analisados comparativamente a outros métodos de reconstrução 3D frente aos valores verdadeiros dos comprimentos das curvas. Também foram realizados experimentos com um objeto concreto, nesse caso, um neon flexível manipulado defronte a um par de câmeras reais. As matrizes de calibração foram determinadas por meio de procedimento específico, o comprimento verdadeiro do objeto foi estimado por meio de medição direta e comparado aos resultados obtidos através da aplicação da snake-3D e outro método de reconstrução 3D. Em seguida a snake-3D foi aplicada a imagens de arcos elétricos reais cuja evolução foi capturada utilizando câmeras reais. Nesses casos as estimativas dos comprimentos por meio de snake-3D foram contrapostas aos estudos baseados na análise dos sinais de tensão e de corrente medidos nas extremidades do arco em evolução. Os comprimentos obtidos com a abordagem proposta foram semelhantes aos obtidos através de medidas elétricas, o que valida o uso da metodologia desenvolvida para este tipo de aplicação
Abstract: The electrical arc length is an important parameter for the arc mathematical modeling. Nowadays the profile of the arc length variation is estimated by the analysis of the voltage measured at the extremities of the arc and the current of the arc. But these results are not conclusive because they do not present a metrical measurement of the three-dimensional medial-axis of the arc. On the other hand, the images of the spatial evolution of the arc can provide enough resources for recovering the 3D longitudinal axis for estimation of the arc length as well as for obtaining the curve of length variation along the time. The main contribution of this work therefore lies in the estimation of the arc length, and consequently the elongation of electric arcs based on the application of the model (3D-snake) for the three-dimensional reconstruction of the longitudinal axes of artificially generated electrical arcs. Different experiments were conducted to evaluate the proposed application of the 3D-snake. Initially, some geometrical characteristics of the arcs were reproduced in parametric curves whose projections formed sequences of image pairs and determined the sets of test cases. Then the results obtained by applying the 3D-snake were analyzed in comparison to other 3D reconstruction methods against the true values of the lengths of curves. Also experiments were performed with a concrete object, in this case, a flexible neon manipulated in front of a pair of real cameras. The calibration matrices were determined by specific procedure, the length of the real object was estimated by direct measurement and compared to results obtained by applying the 3D-snake and other 3D reconstruction method. Next the 3D-snake was applied to real images of arcs whose evolutions were captured using real cameras. In these cases the estimation of measurement through 3D-snake were opposed to results based on arc current and arc voltage measured at arc terminals. The lengths obtained with the proposed model were similar to those obtained through electrical measurements, which validates the use of the method developed for this type of application
Doutorado
Engenharia de Computação
Doutor em Engenharia Elétrica

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Kirchner, Jan. „Vývoj testovacího přípravku délkového snímače“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382107.

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Aim of this thesis is a verification of possibility to measure displacement in small range using sensor based on the principle of strain gauge. For testing purspose, an evaluating unit was designed, made and assembled. This unit contains analog/digital converter, LCD and it has an abbility to move measuring plane using stepper motor. Next part of this thesis is about testing new prototype of strain gauge sensor, including evaluation of results of measuring. The performed measurements were measuring linearity, time stability and repeatability. Based on the results of the measurements, the possibility of using this type of length measuring device was confirmed for further development.

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Gonçalves, Michelle Mantovani. „Mapeamento genético no camarão marinho Litopenaeus Vannamei (Crustacea, Decapoda)“. Universidade Federal de São Carlos, 2009. https://repositorio.ufscar.br/handle/ufscar/5378.

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Universidade Federal de Minas Gerais
Two genetic linkage maps were constructed referent to two full-sib families (G1 and G2) of the marine shrimp species Litopenaeus vannamei, and the integration of these maps was accomplished. The mapping was based on polymorphic markers derived from nine AFLP (Amplified Fragment Length Polymorphism) primers. A total of 103 and 59 segregating polymorphic markers were used in the construction of the maps for families G1 and G2, respectively. The G1 family map consisted of 14 linkage groups, with estimated genome coverage of approximately 350 cM. The G2 map presented 4 linkage groups, with genome coverage of around 300 cM. The integration of the maps evidenced eight AFLP anchor markers in a same linkage group (LG1) in both families, to which 66 markers were allocated, leading to a well saturated linkage group, with estimated genome coverage of 874.16 cM.
Dois mapas genéticos de ligação foram construídos referentes a duas famílias de irmãos completos (G1 e G2) da espécie de camarão marinho Litopenaeus vannamei e foi realizada a integração desses mapas. O mapeamento foi baseado em marcadores polimórficos derivados de nove primers AFLP (Polimorfismo no Comprimento de Fragmentos Amplificados). Um total de 103 e 59 marcadores polimórficos segregantes foram utilizados respectivamente para a construção dos mapas das famílias G1 e G2. O mapa da família G1 consistiu de 14 grupos de ligação, com cobertura estimada do genoma de aproximadamente 350 cM. O mapa da G2 apresentou 4 grupos de ligação, com cobertura do genoma de aproximadamente 300 cM. A integração dos mapas evidenciou 8 marcadores âncoras AFLP em um mesmo grupo de ligação (GL1) em ambas as famílias, no qual foram alocados 66 marcadores, o que conduz um grupo de ligação bem saturado, com estimativa de cobertura do genoma de 874,16 cM.

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Lobato, Mary Túlia Vargas. „Estimativas de parâmetros genéticos e análise dialélica de cruzamentos de trigo (Triticum aestivum L.) envolvendo a cultivar BH-1146 e linhagens irradiadas“. Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-30092010-142033/.

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Visando avaliar o potencial de populações segregantes de trigo obtidas de parentais portadores de características agronômicas contrastantes, quanto ao comprimento da raiz primária, produção de grãos e caracteres agronômicos; estimar a herdabilidade no sentido amplo e restrito para populações F2 obtidas, além das associações das características em estudo; confirmar os genitores mais promissores para utilização em programas de melhoramento de trigo e estimar a capacidade geral e específica de combinação dos genótipos de trigo, foram efetuados cruzamentos, em forma dialélica, entre quatro genótipos de trigo: BH-1146, Anahuac M-1, IAC-287/IAC-24 M-1 e MONS/ALDS// IAC-24 M-3. Foram obtidos híbridos em geração F1 e F2 e os retrocruzamentos RC1 e RC2, que foram avaliados quanto ao comprimento da raiz em solução nutritiva, conforme Camargo e Ferreira Filho (2005a). Após a medição das raízes, as plântulas foram transplantadas para telado do Centro de Grãos e Fibras do IAC sob delineamento de blocos ao acaso, com 28 tratamentos (os 4 parentais, os 6 F1s, F2s, RC1s e RC2s), com 6 repetições. Avaliaram-se os caracteres comprimento da raiz primária, altura das plantas, comprimento da espiga, número de espiguetas por espiga, grãos por espiga, grãos por espigueta, massa de cem grãos, comprimento do internódio da raque, número de espigas por planta, produção de grãos por planta e florescimento. Para análise dialélica foi utilizado o Modelo de Griffing (1956) Os valores estimados para a herdabilidade em sentido amplo, para os seis cruzamentos, foram altas para altura de plantas; médios, na maioria dos cruzamentos, para comprimento da raiz, comprimento da espiga, números de espigas por planta e grãos por espiga, produção de grãos por planta e florescimento; de médios a altos para comprimento do internódio da raque e número de espiguetas por espiga e de médios a baixos para massa de cem grãos e número de grãos por espigueta. Esses valores indicaram que grande parte das variações encontradas foi de origem genética. As estimativas de herdabilidade no sentido restrito (h2r) mostraram grande variação de magnitude nos diferentes cruzamentos para todos os caracteres avaliados. Ressaltou-se o cruzamento P1/P4, com parentais divergentes, com elevados valores de herdabilidade no sentido restrito. Altos valores de h2r foram estimados para altura de plantas em todos os cruzamentos, indicando que a seleção será efetiva nas primeiras gerações segregantes. As correlações fenotípicas revelaram haver uma tendência da seleção de plantas com maior comprimento da raiz primária estar associada com maior produção de grãos por planta e maior precocidade para o florescimento. BH-1146 demonstrou ser fonte genética de tolerância à seca no estádio inicial da cultura do trigo. As análises dialélicas corroboraram os resultados dos ensaios de genótipos, destacando os genótipos P4 como fonte de redução de altura das plantas e o P1 como fonte de aumento do comprimento da raiz; para produção de grãos evidenciaram-se P1 e P2 com elevados valores de capacidade geral de combinação. Detectaram-se efeitos significativos da CEC e CGC, evidenciando a ação de genes preponderantemente aditiva e de dominância na manifestação dos na maioria dos caracteres estudados
Diallel crossing was made with four wheat genotypes: BH-1146, Anahuac M-1, IAC-287/IAC-24 M-1 and MONS/ALDS// IAC-24 M-3, bearing agronomically contrasting characteristics, to evaluate the potential of segregating populations of wheat obtained from parents bearing contrasting agronomic characteristics for primary root length, grain yield and agronomic characteristics; to estimate the herdability, in the broad and narrow senses, for F2 obtained populations in addition to the association of the traits under study; to confirm the more promising parents for use in wheat improvement programs and to estimate the general and specific combining abilities of wheat genotypes. Hybrid were obtained in F1 and F2 generation of RC1 and RC2 backcrossing, which were evaluated for their root length in nutrient solution, according to Camargos and Ferreira Filhos method (2005a). After root measuring, plantules were transplanted to screens of the IAC Center for Grain and Fibers in blocks at random, with 28 treatments (4 parents, the 6 F1s, the 6 F2s, the 6 RC1s and the 6 RC2s), with 6 repetitions. Characteristics such as primary root length, plant length, and spike length, number of spikelet per spike, grains per spike, grains per spikelet, 100 grain weight, length of the rachis internode heigth, number of spike per plant, grain yield per plant and flowering were evaluated. The Griffing Model (1956) was used for the diallel analysis. Herdability estimates were obtained. The herdability estimates in the broad sense for the six crossings were high for plant height in all of them; moderate, in most of the crossings for root growth, spike heigth, number of spikes per plant and grain per spike, grain yield per plant and flowering; were moderate to high for rachis internode height and the number of spikelet per spike and moderate to low for 100 grain weight per spikelet. These values indicated that a large part of the variability found was of genetic origin. Herdability estimates in the narrow sense showed large variability in magnitude in the different crossings for the studied traits. P1/P4 crossing with different parents showed high herdability in the narrow sense. High herdability values in the narrow sense were estimated for plant heigth in all crossings, indicating that the selection will be effective for the first segregating generations. Phenotype correlations showed a tendency for the selection of plants with larger heigth for the primary root being associated with a higher grain yield per plant and higher early flowering. BH-1146 proved to be a genetic source of tolerance to drought in the initial stage of the wheat breeding. Diallel analysis confirm the results of experiments with genotypes, showing high values in the combining ability of P4 genotypes as being the source of reduction of plant heigth, and P1 as source of the increase in root length; P1 and P2 were found with high values of gi for the production of grain. CEC and CGC, showed the action of genes of major aditive effects and prevalence of the traits studies

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Assis, Michelli Cristina Silva de. „Impacto da terapia nutricional sobre infecção e permanência hospitalar em pacientes cirúrgicos : estudo de coorte“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/115584.

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Introdução: A terapia nutricional (TN) em pacientes cirúrgicos é fundamental para o manejo da desnutrição hospitalar, podendo reduzir as complicações pós-operatórias e a ocorrência de desfechos negativos durante a hospitalização. Não há evidências sobre o impacto da TN implementada na prática clínica, como período de jejum pós-operatório (PO) e ingestão de calorias e proteínas, sobre a incidência de infecção e tempo de internação. Objetivo: Verificar o efeito do jejum PO prolongado e da adequada TN sobre infecção e tempo de internação hospitalar. Métodos: Trata-se de um estudo de coorte prospectivo realizado em hospital terciário e universitário. Incluiu-se pacientes adultos submetidos à cirurgia eletiva. Excluíram-se aqueles sem condições de submeter-se à avaliação do estado nutricional, admitidos em unidades de cuidados mínimos e de terapia intensiva, com previsão menor ou igual a 72h de internação e para realização de exames. Os dados demográficos e clínicos, as variáveis de exposição e os desfechos de interesse foram coletados por meio dos registros informatizados da assistência. A avaliação do estado nutricional foi realizada na admissão e a cada sete dias até a alta hospitalar ou o óbito. Considerou-se jejum PO prolongado período maior ou igual a 5 dias e internação prolongada quando 1 dia a mais que a média de cada especialidade. O controle de ingestão foi realizado, pelos pesquisadores, seis vezes por semana em formulários específicos do estudo. Considerou-se TN adequada quando ingestão maior ou igual a 75% do prescrito. Realizou-se análise multivariada e um modelo de regressão logística para verificar as associações e ajustar para os fatores de confusão. Resultados: Os resultados demonstraram que 5,6% dos pacientes analisados ficaram em jejum PO prolongado e 16,2% receberam TN adequada. O jejum PO prolongado foi mais freqüente entre os pacientes da especialidade do aparelho digestivo e proctologia. Após ajuste para variáveis de confusão, verificamos que entre pacientes com jejum PO prolongado o risco para infecção é 2,88 vezes maior (IC95%:1,17–7,16) e o risco para internação prolongada é 4,43 vezes maior (IC95%:1,73–11,35). A TN adequada foi fator de proteção, com redução de 36% (RO=0,36; IC95%: 0,15-0,76) do risco de infecção e de 46% (RO=0,46; IC95%: 0,25-0,84) do risco de internação prolongada. Conclusão: O jejum PO prolongado foi fator de risco independente para infecção e internação hospitalar prolongada. A maioria dos pacientes recebeu inadequada TN e aqueles com adequada TN apresentaram redução do risco de infecção e tempo de internação prolongada.
Background: Nutrition therapy (NT) in surgical patients is important to the management of hospital malnutrition and may reduce postoperative complications and the occurrence of adverse outcomes during hospitalization. There is no evidence on the impact of NT implemented in clinical practice, such as fasting period postoperatively (PO) and intake of calories and proteins, on the incidence of infection and prolonged length of stay. Objective: The aim of this study is to determine the effect of prolonged fasting PO and proper NT on infection and prolonged length of stay. Methods: It is a prospective cohort study conducted in a tertiary, university hospital. Were included adult patients undergoing elective surgery. Those with no conditions for nutritional assessment were excluded, as weel as those admitted in minimal care and intensive care units, with the prediction of a shorter stay (less than 72 hours) or admitted for exams. Demographic and clinical data, the exposure variables, as well as the pertinent endpoints were collected from the electronic records. Nutritional status was assessed upon admission and every seven days until hospital discharge or death. A period equal or longer than 5 days was considered as prolonged PO fasting, and prolonged length of stay when there was 1 extra day as compared to the average of each specialty. Dietary intake control was carried out by researches six times a week. NT was considered adequate if dietary intake was equal to or greater than 75% of the prescribed amount. Data was analyzed using logistic multivariate regression. Results: The results showed that 5.6% of the patients studied, were in prolonged PO fasting and 16.2% had adequate NT. Prolonged PO fasting was more frequent among the patients of the digestive tract and colorectal surgeries. After adjustment for confounding variables, we verified that among patients with prolonged PO fasting the risk for infection is 2.88 times higher (CI 95%:1.17–7.16) and the risk for prolonged stay is 4.43 times higher (CI 95%:1.73–11.35). The adequate NT reduced infection risks by 36% (OR=0.36; 95%CI: 0.15-0.76) and reduced the rates of prolonged hospital length of stay by 46% (OR=0.46; 95%CI: 0.25-0.84). Conclusion: Prolonged PO fasting was an independent risk factor both for infection and prolonged hospital stay. Most patients received inadequate NT, those under adequate NT had reduced infection rates and were less likely to have prolonged hospital length of stay.

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Abbühl, Daniel. „New insights into assembly dynamics of the axoneme in Trypanosoma brucei“. Electronic Thesis or Diss., Sorbonne université, 2023. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2023SORUS357.pdf.

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Les flagelles, également appelés cils, sont des organites complexes qui jouent un rôle important dans la motilité, la reconnaissance sensorielle et la morphogenèse cellulaire. La recherche des mécanismes qui régissent le contrôle de la longueur des flagelles est un domaine de recherche actif. Le projet vise à étudier ce processus chez le parasite protozoaire Trypanosoma brucei, utilisé ici comme organisme modèle. Tout en progressant à travers les différentes étapes du cycle de vie complexe, la longueur du flagelle varie fortement entre les différents stades. Dans la même cellule, T. brucei assemble un nouveau flagelle à côté d'un flagelle mature, dans lequel la poursuite de l'assemblage est empêchée. Le nouveau flagelle s'allonge jusqu'à atteindre ~80% de la longueur du flagelle mature. Les cellules se divisent ensuite et le nouveau flagelle est construit à pleine longueur après la division. Notre groupe a proposé un modèle où les flagelles matures sont verrouillés après leur construction à pleine longueur, par un événement qui a lieu avant la division cellulaire . Dans une collaboration récente, un gène candidat prometteur pour cet événement de verrouillage a été décrit , cependant, le mécanisme reste inconnu. Pour étudier le contrôle de la longueur des axonèmes, nous avons développé un système d'expression inductible de l'alpha-tubuline marquée. En raison de sa dépendance à l'intégrité de la séquence et aux modifications post-traductionnelles, la tubuline marquée en N- ou C-terminal n'est pas incorporée dans l'axonème de T.brucei. Nous avons donc dû adopter une nouvelle approche qui a été réalisée avec succès chez la levure et les cellules de mammifères en marquant l'alpha-tubuline à l'intérieur du gène au lieu d'un marquage sur les extrémités. Nous avons d'abord démontré qu'un tag Ty1 intragénique à l'intérieur de la "boucle d'acétylation" entraîne l'incorporation d'une tubuline marquée similaire à l'alpha-tubuline endogène. La tubuline marquée a ensuite été placée sous la régulation d'un opérateur tétracycline pour rendre l'expression inductible à l'ajout de tétracycline. Avec ce système, nous avons montré que la tubuline n'est en effet assemblée que dans le nouveau mais pas dans l'ancien flagelle, un schéma qui démontre formellement le modèle de verrouillage proposé par notre groupe (Bertiaux et al. 2018) et (les détails et les figures peuvent être trouvés dans le rapport du premier comité). Ensuite, nous avons démontré que les trypanosomes s'engagent à verrouiller leurs flagelles avant la division cellulaire avec une série d'expériences utilisant le téniposide. Ce médicament inhibe la division cellulaire des trypanosomes mais ne perturbe pas la ségrégation des corps basaux, permettant ainsi l'assemblage normal de nouveaux flagelles. Ces expériences ont montré que les cellules qui ne se divisent plus et qui ont deux flagelles complets n'incorporent pas de nouvelle tubuline, ce qui prouve formellement l'engagement des cellules à verrouiller leurs flagelles avant la division cellulaire (rapport de la deuxième commission). Ensuite, nous avons étudié comment les nouveaux flagelles sont terminés après la division cellulaire. Une hypothèse postule que les nouveaux flagelles sont terminés sur plusieurs cycles cellulaires après leur division (Farr et Gull 2007). Pour avoir une idée de la façon dont les flagelles sont remodelés sur des périodes plus longues, nous avons réalisé des expériences de désinduction où la tétracycline a été éliminée après une induction initiale prolongée. Avec les données des expériences d'induction (6-9h), nous pouvons confirmer cette hypothèse et postuler que cette élongation post-division se produit pendant la phase G1. Nous avons également testé le mécanisme de verrouillage au stade du cycle de vie qui est présent dans la circulation sanguine des mammifères et nous pouvons affirmer qu'il est également présent à ce stade
Flagella, also called cilia, are complex organelles that play important roles in motility, sensory recognition and cell morphogenesis. One active field of research is the quest for mechanisms that govern the control of flagellum length. The project aims at investigating this process in the protozoan parasite Trypanosoma brucei, used here as a model organism. While progressing through the different stages of the complex life cycle the length of the flagellum varies greatly between the different stages (3 – 30μm) (reviewed in Rotureau and Van Den Abbeele 2013). In the same cell, T. brucei assembles a new flagellum alongside a mature one, in which further assembly is prevented. The new flagellum is elongated to ~80% of the length of the mature flagellum. The cells then divide and the new flagellum is constructed to full length after division. Our group proposed a model where mature flagella are locked after construction to full length, by an event that takes place before cell division (Bertiaux et al. 2018). In a recent collaboration, a promising gene candidate for this locking event has been described (Atkins et al. 2021), however, the mechanism remains unknown. To investigate the control of axoneme length, we developed a system for the inducible expression of tagged alpha-tubulin. Due to its reliance on sequence integrity and post-translational modifications N- or C-terminally tagged tubulin does not get incorporated into the axoneme of T.brucei. We therefore had to adopt a new approach that has been successfully carried out in yeast and mammalian cells (Sirajuddin et al.) by tagging alpha-tubulin inside the gene instead of a tag on the termini. We first demonstrated that an intragenic Ty1-tag inside the “acetylation loop” results in the incorporation of tagged tubulin similar to endogenous alpha-tubulin. The tagged tubulin was then placed under the regulation of a tetracycline operator to make the expression inducible upon the addition of tetracycline. Whit this system we showed that tubulin is indeed only assembled into the new but not the old flagellum, a pattern that formally demonstrates the locking model proposed by our group (Bertiaux et al. 2018) and (details and figures can be found in the first committee report). Next, we demonstrated that trypanosomes commit to locking their flagella before cell division with a set of experiments utilizing teniposide. A drug that inhibits cell division of trypanosomes but does not temper with basal body segregation, therefore, allowing normal assembly of new flagella. These experiments showed that cells that no longer divide and have two full length flagella do not incorporate new tubulin, which formally proves the cells commitment to locking their flagella before cell division (second committee report). Next, we investigated how new flagella are finished after cell division. One hypothesis postulates that new flagella are finished over several cell cycles after they divided (Farr and Gull 2007). To get an idea on how flagella are remodeled over longer periods of time we performed de-induction experiments where tetracycline was washed out after prolonged initial induction. Together with the data from induction experiments (6-9h) we can confirm this hypothesis and postulate that this post-division-elongation happens during G1-phase. We also tested the locking mechanism in the life cycle stage that is present in the bloodstream of mammals and can claim that it is present there as well

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Persson, Maria, und Emma Ericsson. „Bra jobbat pojkar! : En kvantitativ studie av skillnader i flerspråkiga flickors och pojkars skrivande“. Thesis, Linnéuniversitetet, Institutionen för svenska språket (SV), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-70973.

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Syftet med studien är att undersöka eventuella skillnader i flickors och pojkars skrivande under grundskolans tidigare år. I studien undersöks dagbokstexter skrivna av flerspråkiga flickor och pojkar i årskurs tre. Fokus ligger på att undersöka elevernas text- och meningslängd, långord samt nominalkvot. Tidigare forskning utförd på elever i årskurs nio samt på gymnasiet visar att pojkar tagit ett steg närmare flickorna i vissa aspekter i sin skriftliga komplexitet. Vår studie om elevers skrivande i årskurs tre talar till och med för att pojkarna gått förbi flickorna. Materialet består av tio dagböcker skrivna av sex flickor och fyra pojkar. I studien delar vi in eleverna som skriver texterna i flickor och pojkar, och vi förutsätter därmed att det finns vissa skillnader mellan dem som påverkar deras skriftspråksutveckling. Vi utgår från en positivistisk vetenskapsteori med en viss kvantitativ ansats och med tydligt mätbara textaspekter. De skillnader som studien visar är att pojkar skriver längre texter, har högre nominalkvot samt använder fler långord. Flickorna skriver däremot längre meningar än pojkar.

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Mateika, Andrius. „Mokomųjų tekstų sakinio ilgis ir struktūra“. Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060611_225703-15329.

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Lenght of sentence add structure of educational texts depend on relation between author and recipient, individual style, branches of knowledge. Average lenght of sentence specialize educational texts, it's one of linguist feature. Distributin of language sections also specialize educational texts. Scientific style texts contain usage of intertextual correlation devices oriented towards the textual paradigm of this style.

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Pereira, Viviam Serra Marques. „Efeito de características microestruturais na difusividade do hidrogênio em dois aços grau API X65“. Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-23062017-163732/.

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Os aços de alta resistência e baixa liga são amplamente utilizados em dutos transportadores de óleo e gás e, atualmente, o desenvolvimento de novos projetos de liga e o uso de técnicas altamente avançadas de fabricação e processamento dos aços se tornaram essenciais para obtenção de estruturas que resistam aos danos provocados por H, principal motivo de falha de oleodutos e gasodutos em meios ricos em H2S. No presente trabalho, avaliou-se o efeito de características microestruturais na difusividade do H em dois aços grau API X65, com diferentes teores de Mn. Uma das chapas ainda está em fase experimental de desenvolvimento, tem baixo teor de Mn e foi produzida para aplicação em ambientes sour. A outra chapa tem alto teor de Mn, já é usada comercialmente há alguns anos e foi desenvolvida para trabalho em ambientes doces. Os dois materiais passaram por caracterização microestrutural nas três seções da chapa: longitudinal e transversal à direção de laminação e do topo da chapa (paralela à direção de laminação). Após a caracterização, amostras de cada seção dos aços foram submetidas a ensaios de permeabilidade ao H; o aço baixo Mn passou por análises de EBSD (Difração de Elétrons Retroespalhados), para determinação de textura. O aço baixo Mn tem microestrutura homogênea ao longo da espessura da chapa, composta por ferrita refinada e pequenas ilhas de perlita. O aço alto Mn, por sua vez, apresenta microestrutura heterogênea ao longo da espessura, formada por bandas de ferrita e perlita, com marcada presença de segregação central de elementos de liga. Os ensaios de permeabilidade ao H mostraram que os coeficientes de difusão efetiva do H, Deff, do aço baixo Mn são ligeiramente superiores aos do aço alto Mn. Outros dois importantes parâmetros que foram calculados para os dois aços são a concentração de H na sub-superfície do material, C0, e o número de traps por unidade de volume, Nt. Contrariando expectativas, o aço baixo Mn apresentou maiores valores de C0 e Nt do que o aço alto Mn. Ensaios preliminares de dessorção térmica realizados nos dois aços mostraram os mesmos resultados: o aço baixo Mn aprisiona mais H do que o aço alto Mn. Estes resultados contraditórios de C0 e Nt foram atribuídos à presença de nanoprecipitados de microadições de liga no aço baixo Mn, não detectáveis por microscopia óptica e eletrônica de varredura. Ainda, para os dois aços, os valores de Deff variaram em função da seção analisada da seguinte maneira: Deff longitudinal ? Deff transversal > Deff topo. Para entender melhor o comportamento anisotrópico da difusão do H nos dois aços calculou-se um novo coeficiente de difusão, que foi chamado de coeficiente de difusão no estado estacionário, Dss. O Dss considera que todos os traps do aço estão saturados, permitindo, assim que se avalie somente o efeito de obstáculos físicos à difusão do H. No aço alto Mn, o Dss variou da mesma maneira que o Deff: Dss longitudinal ? Dss transversal > Dss topo; este comportamento foi atribuído ao bandeamento presente no material. No aço baixo Mn, o Dss variou de forma diferente do Deff: Dss transversal > Dss longitudinal >= Dss topo, indicando que a difusão do H pode ser auxiliada por contornos de grão enquanto os traps estão sendo saturados, e que a textura cristalográfica pode influenciar a difusão após o estado estacionário ser atingido.
High strength low alloy steels are widely applied as pipelines for crude oil and natural gas transportation and, currently, new approaches to alloy design, in addition to the use of advanced steelmaking and processing techniques, have become essential for obtaining structures that resist to hydrogen damage, which is the main cause of pipelines failure in H2S-rich environments. The main objective of the present work is to evaluate the influence of microstructural features on hydrogen diffusivity in two API X65 steels, with different Mn contents. One of the steel plates has been recently developed for usage in sour environments, is on its experimental stage and has a low Mn content. The other one is a commercial plate steel, with high Mn content, developed for sweet applications. Both steel plates were characterized in its three sections, in relation to the rolling direction: longitudinal, transverse and top surface of the plate (parallell to the rolling direction). After that, samples obtained from each section of the plates were submitted to hydrogen permeation tests; the low Mn steel was also analysed with EBSD, for texture determination. The low Mn steel presents a homogeneous microstructure through plate thickness, composed of refined ferrite and small pearlite islands. The high Mn steel has a heterogeneous microstructure through the plate thickness, composed of ferrite and pearlite bands, and presents centerline segregation. Hydrogen permeation tests showed that the Deff obtained for the low Mn steel sections are slightly higher than for the high Mn steel. Another two important parameters that were calculated for both steels are the subsurface hydrogen concentration, C0, and the number of traps per unit volume, Nt. Contrary to what was expected, the low Mn steel presented the higher C0 and Nt values. Thermal dessorption spectroscopy analysis confirmed that the low Mn steel traps more H atoms than the high Mn one. These results, along with the similar Deff values, were related to the presence of nanoprecipitates of microalloying elements, that cannot be detected via optical and scanning electron microscopy. Additionally, also for both steels, the Deff values varied in function of the analyzed section as it follows: Deff longitudinal ? Deff transverse > Deff top. In order to better understand this anisotropic behavior, a new diffusion coefficient, which was called diffusion coefficient at the steady state, Dss, was determined. Dss considers that all the trapping sites are saturated, enabling, thus, the evaluation of physical obstacles to H diffusion. For the high Mn steel, the Dss varied in the same matter as the Deff: Dss longitudinal ? Dss transverse > Dss top; this behavior was associated with the microstructural banding present in the material. For the low Mn steel, the Dss exhibited a different behavior: Dss transverse > Dss longitudinal >= Dss top, suggesting that H diffusion can be aided by grain boundaries while the trapping sites are being filled and that crystallographic texture may play its role after the steady state is reached.

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Marquezi, Riciany Alvarenga. „Influência do tempo de jejum e da administração de fluidos perioperatório no tempo de internação e lesão por pressão em pacientes cirúrgicos“. Botucatu, 2019. http://hdl.handle.net/11449/190785.

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Orientador: Paula Schimidt Azevedo Gaiolla
Resumo: A partir da década de 90, muito se discute sobre estratégias para melhorar a recuperação do paciente após a realização da cirurgia. Dentre elas está a redução do tempo de jejum no pré-operatório, com a administração de líquidos claros e a diminuição da infusão de fluidos no intra e pósoperatório. Essas medidas têm sido aplicadas em vários trabalhos e protocolos mostrando-se segura e influenciando no tempo de internação do paciente e em outras complicações. Portanto, os objetivos desse trabalho foram avaliar se o tempo de jejum e o volume infundido no perioperatório influenciam no tempo de internação e no aparecimento de lesão por pressão(LPP) de pacientes cirúrgicos.Para tanto, foram estudados pacientes submetidos a cirurgias do aparelho digestivo, vascular, ortopédica, uroló- gica e ginecológica. Foram avaliados dados demográficos, clínicos e laboratoriais, escalas de risco cirúrgico, de risco para LPP e risco nutricional. Após a cirurgia o paciente foi avaliado quanto ao aparecimento de LPP pela escala de Avaliação e Classificação da LPP e o tempo de internação. A comparação univariada entre os indivíduos que apresentaram ou não LPP ou que ficaram ou não internados por mais de 5 dias, foi realizada pelo teste t de student, Mann Whitnney para as variáveis numéricas, a depender da normalidade de distribuição. A comparação univariada entre as variáveis categóricas foram realizadas pelo teste de qui-quadrado. A regressão logística múltipla foi utilizada para pesquisar variáveis... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Since the 90’s, a lot has been discussed about strategies to improve the recovery of patients after surgery. One of them is the reduction of preoperative fasting time, with the administration of clear liquids and with the decrease of intra and postoperative fluid infusion. As a matter of fact, those measures have been applied in several studies and protocols proving to be safe and influencing hospitalization time and in other complications. Therefore, the objectives of this work were to evaluate if the fasting time and the volume infused in the perioperative, influencing in the hospitalization time and the appearance of pressure injury in surgical patients. Therefore, were studied patients submitted to the following surgeries: digestive, vascular, orthopedic, urological and gynecological. Demographic, clinical and laboratorial data were analyzed, surgical risk scale, risk for pressure injury and nutritional risk. After the surgery, the patient was evaluated for the appearance of pressure injury by the Evaluate Scale and Classification of Pressure injury and hospitalization time. The univariate comparison between the individuals who presented or not the pressure injury time of hospitalization lower than five days or higher than five days was performed by the tstudent test and Mann Whitnney for the numerical variables, depending on the normality of the distribution. The univariate comparison between the categorical variables were made through the qui-square test. The multiple l... (Complete abstract click electronic access below)
Mestre

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CAPUA, G. DI. „CHARACTERIZATION OF HUMAN TENEURIN-4 TRANSCRIPT IN OVARIAN CANCER DERIVED CELL LINES“. Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/171959.

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Teneurins are transmembrane glycoproteins encoded by ODZ genes. Teneurins are a unique protein family conserved from flies and worms to human and are mainly expressed in the developing and adult nervous system where they are thought to be crucial for neurogenesis and axon-guidance. Teneurins are also expressed outside CNS where they have been proposed to play a role in morphogenesis and cell migration. Vertebrate teneurin expression pattern has been studied most extensively in mice and chicken, however still very little is known about their biological function and mechanism of action in humans. Moreover, experimental data concerning the molecular structure of vertebrate teneurins transcripts is scarce, and human ODZ4 messenger has not been subject to a detailed characterization before. Furthermore, recent studies have evidenced that some ODZs, specifically ODZ2 and 4, could be involved in tumor development in a still unclear mode. To this respect, in our preliminary study we demonstrated the expression of ODZ2 in human ovarian and breast cancer-derived cell lines by RT-PCR. Therefore, in this thesis work we have evaluated the expression of ODZ4 in human ovarian and breast cancer-derived cell lines by RT-PCR. As a result, we have characterized two partial ODZ4 full-length messengers expressed by these cell types. The exon-expression pattern analysis indicates that these ODZ4 transcripts can be differentiated by the presence of an insert region corresponding to a non-adjacent genomic sequence that lies between exons 6 and 7. Additionally, the number of exons expressed differs depending on the type of cell line analyzed, even though they may derive from the same tissue type. Further, exonic deletions were not detected along these ODZ4 transcripts but many other truncated splice variants were observed. This study intends to generate new molecular information necessary for the elucidation of the functional role of ODZ4 in human cancer.

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Ramírez, Sebastià Anaïs. „Reconstruction of endodontically treated anterior teeth“. Doctoral thesis, Universitat Internacional de Catalunya, 2014. http://hdl.handle.net/10803/146257.

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L’objectiu d’aquesta tesis es va centrar en la restauració de les dents endodonciades en el sector anterior. Es va evaluar l’adaptació marginal, la resistencia a la fractura, i el tipus de fractura entre dents anteriors restaurades amb endocorones de composite i ceràmica, i corones de ceràmica i composite amb prèvia col.lcació de postes de fibra de 5mm o 10mm de longitud. 32 incisius centrals anteriors van ser dividits en 6 grups experimentals. 1) Poste llarg + munyó de composite + corona CAD/CAM de ceràmica, 2) Poste curt + munyó de composite + corona CAD/CAM de ceràmica, 3) Poste llarg + munyó de composite + corona CAD/CAM de composite, 4) Poste curt + munyó de composite + corona CAD/CAM de composite, 5) Endocorona de ceràmica, 6) Endocorona de composite. Una vegada restaurades les dents, es van carregar sobre una superfície palatina amb una angulació de 45 graus seguint l’eix longitudinal de l’arrel a la màquina de fatiga realitzant 600.000 cicles mecànics a una força de 49N i 1500 cicles termals entre 5 i 55ºC. Abans i després de la prova de fatiga es van realitzar rèpliques de cada mostra per analitzar les dues interfases adhesives externes (Dentina-Ciment i Ciment-Corona) mitjançant un “Microscopio Óptico de Barrido” (SEM) a 200x de magnificació. Es va evaluar així la continuïtat (C) o no continuïtat (MO) de cada interfase. Posteriorment cada dent es va col.locar a un suport de 45º i es va aplicar una força controlada amb una bola d’acer inoxidable. La pressió es va localitzar 3mm per sota de l’eix incisial a la superfície palatina de la corona a una velocitat màxima de 1mm/min. Totes les mostres es van carregar fins aconseguir la seva fractura amb Newtons (N). Els tipus de fractura es van analitzar i es van classificar com a fractura reparable o no reparable o catastròfica. Les fractures a la part inicisal de l’arrel, al munyó i la descimentació del poste es van valorar com a reparables i les fractures per sota, no reparables.

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Nye, Jessica 1986. „Adaptive history of the chimpanzee subspecies in the genomic era“. Doctoral thesis, Universitat Pompeu Fabra, 2018. http://hdl.handle.net/10803/665624.

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Although universal and unavoidable, aging does not occur in a uniform way. In this dissertation, we assessed the effects of early life exposure to pro-inflammatory risk factors (air pollution and obesity) on mitochondrial DNA (mtDNA) content and telomere length, considered as markers of biological aging, at birth and during childhood. First we observed that an increment in nitrogen dioxide (NO2) exposure during pregnancy was associated with a decrease in both placental mtDNA content and birth weight and length (chapter 2 and 3). Secondly, we showed that the association between prenatal NO2 exposure and infant growth could be mediated by placental mtDNA content (chapter 2 and 3). Thirdly, our study found that increased pre- and postnatal exposure to air pollutants lead to shorter leukocyte telomere length in 8 year old children (chapter 4). Finally, we showed that increased obesity indicators were associated with significant shorter telomeres in 8 year old children (chapter 5).
Tot i que és universal i inevitable, l'envelliment no es produeix de manera uniforme. En aquesta tesi, es van avaluar els efectes de l'exposició primerenca a factors de risc proinflamatoris (contaminació de l'aire i obesitat) sobre el contingut d'ADN mitocondrial (mtDNA) i la longitud del telómero, considerats com a marcadors de l'envelliment biològic, en néixer i durant la infància. En primer lloc, vam observar que un increment de l'exposició al diòxid de nitrogen (NO2) durant l'embaràs es va associar amb una disminució tant del contingut de ADN de la placenta plasmàtica com del pes i la durada del part (capítols 2 i 3). En segon lloc, vam mostrar que l'associació entre l'exposició NO2 prenatal i el creixement infantil podria estar mediada per contingut de ADN de placenta (capítols 2 i 3). En tercer lloc, el nostre estudi va descobrir que l'augment de l'exposició pre i postnatal als contaminants atmosfèrics conduir a una menor longevitat de leucòcits en nens de 8 anys (capítol 4). Finalment, vam mostrar que un augment dels indicadors d'obesitat es van associar amb telòmers més curts significatius en nens de 8 anys (capítol 5).

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Saito, Daniel 1974. „Caracterização das comunidades bacterianas associadas as infecções endodonticas : abordagem independente de cultivo“. [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288628.

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Orientador: Reginaldo Bruno Gonçalves
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A presente tese teve como objetivo a caracterização das comunidades bacterianas associadas às infecções endodônticas pelo emprego de técnicas moleculares independentes de cultivo. Ao todo, foram analisadas amostras intra-radiculares provenientes de 34 elementos dentários associados a infecções endodônticas. A análise de bibliotecas clonais de DNA ribossomal 16S (16S rDNA) permitiu a identificação de 2 a 14 filotipos bacterianos (espécies) por elemento dentário (média= 9,6), perfazendo um total de 46 filotipos distintos. Dentre estes, 9% foram considerados previamente desconhecidos e classificados taxonomicamente como novos membros da ordem Clostridiales. Espécies reconhecidamente endodônticas dos gêneros Bacteroides, Campylobacter, Eubacterium, Peptostreptococcus, Selenomonas, Treponema e Veillonella foram detectadas, assim como representantes de gêneros menos freqüentemente descritos, como Burkholderia, Filifactor e Megasphaera. O emprego da técnica quantitativa de PCR em Tempo Real, possibilitou a detecção de P. gingivalis, T. forsythia e a coexistência de ambas em 24%, 56% e 18% dos pacientes avaliados, respectivamente. Nenhuma correlação significativa foi evidenciada entre os níveis de ambas as espécies, individualmente ou em conjunto, e a presença de sintomatologia dolorosa. O uso de T-RFLP na avaliação da estrutura das comunidades bacterianas revelou um total de 123 (endonuclease HhaI) e 122 (endonuclease MspI) fragmentos de restrição terminais (T-RFs) distintos, com médias de 20,8 e 20,0 T-RFs por elemento dentário, respectivamente. Aproximadamente 50% dos fragmentos detectados apresentaram-se, no máximo, em 2 pacientes, indicando uma alta variabilidade na composição microbiana. As análises de clusterização e de estatística multivariada não revelaram diferenças significativas nas comunidades bacterianas entre os grupos de estudo assintomático, sensível ao toque e sintomático. De modo geral, os resultados obtidos reiteraram o conceito de que a microbiota associada às infecções endodônticas é essencialmente polimicrobiana, altamente variável entre indivíduos, e constituída predominantemente por bactérias anaeróbias Gram-positivas do filo Firmicutes. As espécies P. gingivalis e T. forsythia, embora relativamente prevalentes nas infecções endodônticas, não apresentaram correlação significativa com o desenvolvimento de sintomatologia dolorosa. Por fim, a ausência de agrupamentos de perfis bacterianos quanto aos parâmetros sintomatológicos sugere que a estrutura das comunidades bacterianas intra-radiculares não possui influência significativa no desenvolvimento da dor de origem endodôntica
Abstract: The objective of the present study was to characterize the bacterial communities associated with endodontic infections by use of culture-independent molecular techniques. Overall, 34 intraradicular samples from teeth harboring endodontic infections were evaluated. 16S ribosomal DNA (16S rDNA) clone library analysis allowed the identification of 2 to 14 bacterial phylotypes (species) per tooth (mean= 9.6), with a total of 46 distinct phylotypes. Among the latter, 4 (9%) were considered previously unreported and further taxonomically classified as members of the order Clostridiales. Well-known endodontic representatives of Campylobacter, Eubacterium, Peptostreptococcus, Selenomonas, Treponema e Veillonella were detected, as well as members of less frequently reported genera, such as Burkholderia, Filifactor and Megasphaera. The application of the Real Time PCR technique permitted the detection of P. gingivalis, T. forsythia and a coexistence of both in 24%, 56% e 18% of the subjects, respectively. No significant correlations were evidenced among the levels of P. gingivalis and T. forsythia, individually or conjointly, and spontaneous endodontic pain. The use of T-RFLP in the analysis of bacterial community structures revealed a total of 123 (HhaI endonuclease) and 122 (MspI endonuclease) distinct terminal restriction fragments (T-RFs), with 20.8 and 20.0 mean T-RFs per tooth, respectively. Approximately 50% of the detected fragments were exclusive to one or two patients, indicating a high inter-subject variability in the bacterial assemblages. Cluster and multivariate statistical analyses did not demonstrate significant differences in the bacterial community profiles among the asymptomatic, tender to percussion and symptomatic study groups. Taken together, the results of this study reiterate the concept that the microbiota associated with endodontic infections is essentially polymicrobial, highly variable among individuals, and predominantly composed of Gram-positive anaerobic bacteria from the phylum Firmicutes. The species P. gingivalis and T. forsythia, although relatively prevalent in root canal infections, did not present significant correlations with the development of symptomatic features. Lastly, the absence of clusters of bacterial profiles according to symptomatic parameters suggests that the intraradicular bacterial community structures, as a whole, do not bear significant influence on the development of pain of endodontic origin
Doutorado
Microbiologia e Imunologia
Doutor em Biologia Buco-Dental

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Hallgren, Angelica, und Isabelle Randberg. „Mellanchefers psykosociala arbetsmiljö : Skiljer sig upplevelsen beroende på kön och anställningstid?“ Thesis, Högskolan i Gävle, Avdelningen för socialt arbete och psykologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-24568.

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The purpose of this quantitative study was to examine if there were any differences regarding work motivation, stress and role conflict among middle managers depending on gender and length of service. The psychosocial environment is defined by inner work motivation, stress and role conflict. Another purpose with the study was to examine whether there were any interactions between gender and length of work. The study was conducted at a larger industrial company in Sweden where a total of 44 middle managers took part in the study by answering a paper survey. The measuring instruments used were Basic Need Satisfaction at workscale (BNS) measured inner work motivation and the instrument COPSOQ measured stress and role conflict. The result showed a significant difference regarding length of work and relatedness whereas those with a longer length of work estimated a higher estimation compared to those with a shorter length of work. The result showed no more differences regarding length of work and no differences depending on gender and therefore neither any interaction effects.
Syftet med denna kvantitativa studie var att undersöka om det förelåg några skillnader i mellanchefers upplevelse av den psykosociala arbetsmiljön beroende av kön och anställningstid. Den psykosociala arbetsmiljön definieras här utifrån inre arbetsmotivation, stress och rollkonflikter. Ytterligare syfte var att undersöka om någon interaktionseffekt fanns mellan kön och anställningstid. Studien genomfördes på ett större industriföretag i Mellansverige med totalt 44 mellanchefer som deltog genom att besvara en pappersenkät. Mätinstrument som användes var Basic Need Satisfaction at workscale (BNS) som mätte inre arbetsmotivation samt instrumentet COPSOQ som mätte stress och rollkonflikter. Resultatet visade på en signifikant skillnad gällande anställningstid och samhörighet, där de med en längre anställningstid skattade upplevelsen av samhörighet högre jämfört med de med kortare anställningstid. Resultatet visade inga fler skillnader gällande anställningstid samt inga skillnader beroende av kön och därmed inte heller någon interaktionseffekt.

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Souza, Danielle Mandacaru. „A ger?ncia de leitos em um hospital polo da regi?o ampliada de sa?de Jequitinhonha“. UFVJM, 2016. http://acervo.ufvjm.edu.br/jspui/handle/1/1295.

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Data de aprova??o ausente.
Disponibiliza??o do trabalho em conte?do parcial, conforme Termo de Autoriza??o.
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O presente estudo buscou identificar a funcionalidade da Ger?ncia de leitos em um hospital polo da Regi?o Ampliada de Sa?de Jequitinhonha e da Regi?o de Sa?de Diamantina. Com abordagem qualitativa, o estudo foi realizado por meio de entrevistas gravadas e informa??es coletadas dos Sistemas de Processamento de Dados SPDATA. Entrevistou-se 89 colaboradores, sendo quatorze enfermeiros, quinze m?dicos, nove administrativos, doze funcion?rios da higieniza??o, sete profissionais da recep??o e trinta e tr?s t?cnicos de enfermagem. Realizou-se a an?lise de conte?do das entrevistas com base na metodologia de Minayo. Organizaram-se as informa??es coletadas em categorias tem?ticas: A funcionalidade da gest?o de leitos na organiza??o dos processos de entrada e sa?da dos pacientes; A responsabilidade da comunica??o como ferramenta para a instala??o do processo de Gest?o de Leitos; O direcionamento dos pacientes para a cl?nica certa ap?s a implanta??o da GL; A gest?o de leitos e a hotelaria hospitalar; Organiza??o do servi?o hospitalar ap?s a Gest?o de Leitos; Influ?ncia da Gest?o de Leitos na organiza??o das cirurgias eletivas. Esse estudo mostrou que o gerenciamento e melhoria do fluxo de pacientes ao longo das interna??es hospitalares s?o importantes, que o servi?o de Gerenciamento de Leitos buscou utilizar cada leito hospitalar em sua m?xima, diminuiu a espera para as interna??es, tanto eletivas quanto de urg?ncias. Com esse servi?o, a equipe multidisciplinar tem mais seguran?a na gera??o das informa??es sobre o leito que ser? ofertado para o paciente, al?m de tornar o processo de interna??o r?pido e eficiente.
Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Ensino em Sa?de, Universidade Federal dos Vales do Jequitinhonha e Mucuri, [2016].
This study sought to identify the functionality of beds Management on a pole hospital Jequitinhonha Extended Health Region and the Diamantina Health Region. With a qualitative approach, the study was conducted through recorded interviews and information collected from SPDATA Data Processing Systems. She interviewed 89 employees, with fourteen nurses, fifteen doctors, nine administrative, twelve employees of hygiene, seven professional reception and thirty-three nursing technicians. We conducted content analysis of the interviews based on Minayo methodology. Organized the information collected in thematic categories: The functionality of bed management in the organization of the procedures and exit of patients; The responsibility of communication as a tool for installing the bed management process; The direction of patients to the right clinic after the implementation of the bed management; The management of beds and hospital catering; the hospital service organization after he bed management; bed management influence in the organization of elective surgeries. This study showed that the management and improve the flow of patients through the hospital admissions are important, the beds Management service sought to use every hospital bed at its maximum, decreased waiting for hospitalizations, both elective as emergency. With this service, the multidisciplinary team has more security in the generation of information about the bed which will be offered to the patient, in addition to making the quick and efficient admission process.

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Pitarello, Patricia da Rocha Pennachiotti. „Avaliação do colo uterino pela ultrassonografia transvaginal para predição do sucesso da indução do parto“. Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5139/tde-27072011-174211/.

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Objetivo: Correlacionar as variáveis ultrassonográficas do colo uterino ao sucesso da indução do parto e ao Índice de Bishop. Métodos: Estudo observacional prospectivo envolvendo 190 gestantes candidatas à indução do parto, que foram submetidas à ultrassonografia transvaginal para avaliação do comprimento do colo uterino, da distância da apresentação fetal ao OCE, dilatação cervical e identificação da imagem em funil no OCI, no período de fevereiro de 2008 a fevereiro de 2010. As pacientes foram categorizadas segundo o escore de Bishop em favoráveis e desfavoráveis à IP. Os seguintes desfechos foram analisados: probabilidade de sucesso da IP, parto vaginal em 24 horas e presença de fase ativa do parto. A análise estatística foi realizada usando testes qui-quadrado, teste t-Student e Mann- Whitney para as variáveis numèricas, além do cálculo das curvas ROCs para cada variável e cada desfecho. Através de regressão logística foram avaliados os preditores dos desfechos assim como determinadas equações de probabilidade dos eventos. Resultados: O sucesso da IP, o parto vaginal em 24 horas e a presença de fase ativa do parto foram observados em 133 (70%) 119 (62%) e 155 (82%) das gestantes, respectivamente. O comprimento do colo uterino, a distância da apresentação fetal ao OCE, a dilatação cervical e a presença da imagem em funil no OCI influenciaram o sucesso da IP, a presença de parto vaginal em 24 horas e a presença de fase ativa do parto, principalmente em gestantes com escore de Bishop desfavorável à IP. As variáveis ultrassonográficas apresentaram sensibilidade entre 63 e 71% e especificidade entre 63 e 82% e acurácia média de 70%. O escore de Bishop se correlacionou diretamente à dilatação cervical e inversamente ao comprimento do colo uterino e à distância da apresentação fetal ao OCE e foi preditor independente de todos os desfechos da indução do parto (p<0,001). Conclusão: O comprimento do colo uterino, a distância da apresentação fetal ao OCE, a dilatação cervical e presença da imagem em funil no OCI se relacionaram ao sucesso da IP, porém com baixo poder de predição
Objective: To correlate the ultrasonographic variables of cervix to the success on labor induction (LI) and Bishops Index. Methods: A prospective, observational study involving 190 pregnant women that were applicant for labor induction, submitted to transvaginal ultrasound to evaluate the cervixs length, fetal head-external os distance, cervical dilatation and identification of funnel image on internal os, during the period between February 2008 and February 2010. Patients were classified according to Bishops score as favorable and unfavorable to labor induction. The following conclusions were studied: success probability to LI, vaginal delivery in 24 hours and presence of labors active phase. Statistical analysis was performed using chi-square tests, t-Student and Mann-Whitney test for numerical variables, in addition to ROCs curves calculation for each variable and each conclusion. By logistic regression, the conclusion predictors were evaluated, as well as some determined equations from events probability. Results: The labor induction success, vaginal delivery in 24 hours, and presence of labors active phase were noticed on 133 (70%), 119 (62%) and 155 (82%) pregnant women, respectively. Cervixs length, fetal head-external os distance, cervical dilatation and identification of funnel image on internal os influenced the LI success, vaginal delivery at 24 hours and presence of labors active phase, especially on pregnant with Bishops score unfavorable to labor induction. Ultrasonographic variables had sensitivity between 63 and 71%, specificity between 63 and 82%, and 70% of average accuracy. Bishops score was directly correlated to cervical dilatation and inversely correlated to cervixs length and fetal head-external os distance and was a independent predictor to all conclusions of labor induction (p<0.001). Conclusion: The cervixs length, fetal head-external os distance, cervical dilatation and identification of funnel image were related to LI success but with low prediction potency

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Vendel, Jiří. „Spolupůsobení bezstykové koleje a mostní konstrukce“. Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225565.

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The aim of the dissertation is to compare different analysis of the interaction continuous welded rail and bridge in the domestic and foreign literature and to compare the provisions of the prescription S3 Permanent way structure and ČSN EN 1991-2 (73 6203) Eurocode 1: Actions on structures - Part 2: Traffic loads on bridges.

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Lima, Augusto PlÃcido Cavalcante Melo de. „Espectros de energia na mecÃnica quÃntica polimÃrica“. Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17641.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
A formulaÃÃo e comprovaÃÃo experimental de uma teoria consistente de GravitaÃÃo QuÃntica Ã um dos maiores desafios da FÃsica atualmente. Entre as candidatas a ocupar este posto estÃ a GravitaÃÃo QuÃntica de LaÃo, ela sugere a reinterpretaÃÃo do espaÃo-tempo que, em escala planckiana, assume a forma de uma rede de pontos espaÃados por um comprimento mÃnimo caracterÃstico da natureza. Neste trabalho tratamos de um modelo recentemente introduzido que incorpora o conceito de comprimento mÃnimo e o aplica no contexto de baixas energias, a MecÃnica QuÃntica PolimÃrica, discutimos a diferenÃa entre a fÃsica deste modelo e dos modelos de incerteza mÃnima, em especial o PrincÃpio de Incerteza Generalizado, onde a discretizaÃÃo espacial e consequÃncia de alteraÃÃes nas relaÃÃes de comutaÃÃo canÃnicas. Usamos o mÃtodo perturbativo para calcular correÃÃes de primeira ordem nos espectros de energia de alguns potenciais conhecidos, observamos atravÃs de grÃficos as escalas de energia envolvidas e comparamos os resultados com outras correÃÃes que surgem no contexto de altas energias.
The formulation and experimental verication of a consistent theory of Quantum Gravitation is one of the greatest challenges in Physics nowadays. Between the candidates for this post is the Loop Quantum Gravity, it suggests a reinterpretation of space-time, that in planckian scale, would assume the form of a net of points spaced by a minimal length characteristic of nature. In this work we deal with a model that incorporates this concept and applies it to the context of low energies, the Polymer Quantum Mechanics, we discuss the dierences on the physics of this model an that of the model on minimal uncertainty, in special the Generalized Uncertainty principle, where the spacial discretization is a consequence of modications in canonical commutation relations. We use the perturbative method to calculate rst order corrections in the energy spectra of some known potentials, we observe through graphics the energy scales involved and compare the results with other corrections that arise in the context of high energies.

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Komínková, Eva. „Perspektivy mladých lidí v kontextu trhu práce“. Master's thesis, Vysoká škola ekonomická v Praze, 2017. http://www.nusl.cz/ntk/nusl-359616.

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Family and reproductive behaviour shapes the outline of Czech Republic. Regime changes after 1989 certainly influenced the whole society. Critical changes in demographic behaviour need to be viewed in context of economic, social and cumtural changes in society. The purpose of this thesis is to explore perspectives of young adults, with an emphasis on exploring links between demographic behavious and on job market between 1989 and 2015. Thus this thesis should provide an answer to a question on how signifikance of influence of e.g. parenthood on career paths of youg people. To achieve this target, we used mainly publicly available data provided by Czech Statistical Bureau, interchangeably with data from Eurostat and basic statistical analysis.

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Brunet, Annaël. „Etude à l'échelle de la molécule unique des changements conformationnels de la molécule d'ADN : influence de la présence de défauts locaux présents sur l'ADN et de paramètres physico-chimiques de la solution environnante“. Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30168/document.

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Les ions jouent un rôle majeur sur les processus biologiques affectant la molécule d'ADN que ce soit en termes d'activité de liaison de protéines à l'ADN ou d'encapsulation de l'ADN dans les capsides virales ou le noyau. L'activité de protéines sur l'ADN est, par ailleurs, fréquemment liée à une courbure locale de l'axe de la double hélice, que ce soit en raison d'une séquence intrinsèquement courbée, ou, via la capacité de protéines à courber la séquence sur laquelle elles se fixent. Être capable de caractériser et comprendre l'effet des ions présents en solution, de la courbure et de la dénaturation locale de la molécule d'ADN sur les conformations de cette dernière est donc crucial pour approfondir la compréhension de nombreux processus biologiques. Des travaux, tant expérimentaux que théoriques, ont déjà été menés sur ces questions mais celles-ci sont encore largement débattues. En effet, pour y répondre, doivent notamment être développées des méthodes expérimentales qui ne perturbent pas significativement la conformation de l'ADN ou le complexe ADN-protéine, ainsi que des modèles théoriques associés permettant une analyse précise des données expérimentales et leur compréhension physique. L'objectif de ce travail est de proposer des outils expérimentaux et théoriques permettant de décrire physiquement l'influence de défauts locaux présents sur la molécule d'ADN et de paramètres physico-chimiques de la solution environnante. A cette fin, des données expérimentales ont été acquises à l'échelle de la molécule unique grâce à la technique haut-débit de "Tethered Particle Motion" (HT-TPM). Le TPM consiste à enregistrer, au cours du temps, les positions d'une particule accrochée à l'extrémité d'une molécule d'ADN, immobilisée par son autre extrémité sur un support en verre. L'utilisation d'une biopuce permettant la parallélisation des complexes ADN/particule et l'acquisition "à haut débit" de données TPM a permis d'obtenir une grande accumulation de statistiques individuelles. Une procédure d'analyse efficace a été élaborée afin de déterminer les amplitudes du mouvement des assemblages ADN-particules valides. En parallèle, ont été effectuées des simulations basées sur un modèle de physique statistique mésoscopique dans lequel la molécule d'ADN est assimilée à une chaîne de billes de rayons variables dont les déplacements sont régis par la diffusion brownienne et une énergie potentielle d'interaction prenant en compte notamment l'énergie de courbure du polymère ADN. Une première étude a porté sur l'effet de la force ionique de la solution environnante sur la longueur de persistance Lp, qui traduit la rigidité du polymère d'ADN. Les valeurs de Lp extraites des données de HT-TPM ont fait apparaître une décroissance de la longueur de persistance de 55 à 30 nm, corrélée à l'augmentation de la force ionique, avec une décroissance plus forte observée pour les ions divalents Mg2+ que pour les ions monovalents Na+. Les valeurs de Lp déterminées sur une plage étendue de force ionique ont permis de valider l'approche théorique proposée par Manning en 2006 dans la cas Na+. Une deuxième étude a conduit à l'élaboration d'une méthode permettant de quantifier l'angle de courbure locale induite par une séquence spécifique ou la liaison d'une protéine sur la molécule d'ADN. L'échantillon modèle a été obtenu en insérant de une à sept séquences CAAAAAACGG en phase. Une description théorique de la chaîne d'ADN appelée "kinked Worm-Like Chain" a été proposée. Elle conduit à une formule simple de la distance bout-à-bout de l'ADN qui permet d'extraire la valeur de l'angle de courbure à partir des mesures de HT-TPM. Ainsi, il a pu être montré que la séquence CAAAAAACGG induit un angle de 19° ± 4° en accord avec les données de la littérature. Une troisième étude concernant la mesure de l'impact de la dénaturation partielle de l'ADN, induite par la température, sur sa rigidité apparente globale a été menée. Des résultats préliminaires sont proposés
Ions play an important role in many biological processes affecting the DNA molecule, both for binding activities of DNA-protein interaction, and the DNA packaging in viral capsids or in the cell nucleus. Proteins actions on DNA are also often associated to the double helix curvature, be it because of an intrinsic curved sequence, or of the ability of the proteins, to curve the sequence they are trying to bind. Being able to characterize and understand the effects on the DNA conformation of ions present in solution, DNA local curvature, and local denaturation bubble is essential and crucial for the thorough understanding of many biological processes. Many experimental, and theoretical studies have already been conducted to address these questions. However they remain highly debated. To answer then one must notably develop experimental approaches that minimize alteration of the conformation of the DNA molecule or the complex protein-DNA, as well as associated theoretical models that permit a precise analysis of experimental data as well as their physical understanding. The goal of this work is to develop and propose experimental and theoretical tools which would provide a physical description of the influence of DNA local defects on the DNA molecule as well as of physicochemical conditions of the DNA environmental solution. For this purpose, experimental data have been collected, at a single molecule level, using the High-Throughput Tethered Particle Motion" (HT-TPM) technique. TPM consists of recording the location of a particle grafted by one end of a single DNA molecule and immobilized, at the other end, to a glass surface. The use of a biochip that enables the parallelization of DNA/particle complexes and the ensuing high-throughput data acquisition permitted to obtain a large accumulation of individual statistics. A strong analysis procedure has been developed to extract and quantify the amplitude of motion of the valid DNA/particle complexes . Alongside that, simulations have been run, based on a mesoscopic statistical mechanics model in which the DNA molecule is related to a chain of monomers with varying radius and in which the amplitude of motion is governed by both the Brownian motion and by the interaction potential associated to stretching and bending energies of the polymer. A first study was conducted on the effect of the ionic strength induced by surrounding ions in solution on the DNA persistence length (Lp) which characterizes the DNA polymer rigidity. The extracted Lp values of HT-TPM measurement decrease from 55 to 30 nm when the ionic strength increases. A stronger decrease was observed in presence of divalent ions Mg2+ than with monovalent ions Na+. This quantification of Lp dependence, on a large and strongly prospected range of ionic strengthes, tends to validate the theoretical approach proposed in 2006 by Manning in presence of monovalent ions Na+. A second project allows us to develop a method of evaluation and quantification of local DNA bending angles, induced either by specific intrinsic sequence, or by the binding of proteins on DNA. Constructs made of 575 base-pair DNAs with in-phase assemblies of one to seven sequences CAAAAAACGG was used. A theoretical description of the polymer chain, named "kinked Worm-Like Chain" was proposed which leads to a simple formulation of the end-to-end distance of DNA molecules allowing to extract local bend angles from HT-TPM measurement. As a result, we find that the sequence CAAAAAACGG induces a bend angle of 19° ± 4° in agreement with other value from the literature. A third study concerning the influence of temperature-induced partial denaturation on the global apparent rigidity parameters of the polymer was conducted. Preliminary results are proposed

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López, Sánchez Ángel. „Influencia del proceso de reciclado sobre las propiedades de los materiales compuestos obtenidos por inyección de poliestireno reforzado con fibras lignocelulósicas“. Doctoral thesis, Universitat de Girona, 2004. http://hdl.handle.net/10803/7759.

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The objective of this research is to study the influence of several recycling cycles on the mechanical properties of four different materials made by the injection of polystyrene.
The four materials studied have different characteristics. The first one is polystyrene (PS), the second one is polystyrene reinforced with hemp fibers (PSf), the third one is polystyrene reinforced with hemp fibers modified with AKD (PSft) and the last one is polystyrene reinforced with fiberglass (PSfv). With all these materials tensile strength, bending, hardness and impact is measured. After the measurement of these physical properties, materials are recycled to obtain new injection samples, and its physical properties are measured again. This process is repeated during 24 cycles.
After each recycling cycle material physical properties are related with polystyrene molecular weight, melt flow, FTIR spectra and DSC.
From reinforced materials, fibers are recovered and through microscopy and image analysis they are characterized to study the influence that recycling has on its structure.

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Olsson, Jens. „Interplay Between Environment and Genes on Morphological Variation in Perch – Implications for Resource Polymorphisms“. Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7212.

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Cerocchi, Filippo. „Dynamical and Spectral applications of Gromov-Hausdorff Theory“. Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENM077/document.

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Cette thèse est divisée en deux parties. La première est consacrée à la méthode du barycentre, introduite en 1995 par G. Besson, G. Courtois et S. Gallot pour résoudre la conjecture de l'Entropie Minimale. Dans le Chapitre 1 nous décrivons ses développements les plus récents, notamment l'extension de cette méthode au cadre des variétés dont la courbure sectionnelle est de signe quelconque (voir les énoncés 1.2.1 et 1.4.1). Dans le Chapitre 2 et 3 nous présentons des résultats dans lesquels la méthode du barycentre joue un rôle important. Le problème “deux variétés dont les flots géodésiques sont conjugués sont-elles isométriques ?” (problème de la rigidité par conjugaison des flots) est le thème du Chapitre 2. Après avoir montré que deux telles variétés ont la même géométrie à grande échelle, on montre comment on peut utiliser ce résultat et la méthode du barycentre pour donner une nouvelle preuve de la rigidité (par conjugaison des flots) des variétés plates. Dans le Chapitre 3 nous utilisons la méthode du barycentre (en courbure de signe quelconque) et des inégalités de Sobolev itérées pour démontrer un théorème de comparaison entre les spectres de deux variétés riemanniennes (Y , g) et (X , g') de volumes proches, sachant qu'il existe une approximation de Gromov-Hausdorff de degré non nul entre ces deux variétés. Il s'agit d'un résultat d'approximation avec majoration de l'erreur d'approximation (et pas seulement d'un résultat de convergence). Remarquons qu'il n'est fait aucune autre hypothèse géométrique (et en particulier aucune hypothèse de courbure) sur la variété (Y , g), ce qui autorise un grand nombre de contre-exemples prouvant que le résultat est optimal. Dans la deuxième partie de la thèse (chapitre 4), on démontre un Lemme de Margulis sans hypothèse sur la courbure, qui s'applique aux variétés dont les groupes fondamentaux sont des produits libres (et qui ne possèdent pas d'élément de torsion d'ordre 2). Nous donnons également une borne inférieure de la systole des variétés dont le diamètre et l'entropie volumique sont majorés et dont le groupe fondamental est isomorphe à un produit libre sans torsion. Comme conséquences de ce dernier résultat nous obtenons des résultats de précompacité et de finitude topologique ou différentiable pour les variétés riemanniennes et une minoration de leur volume, tout ceci sans faire d'hypothèse de courbure
This Ph.D. Thesis is divided into two parts. In the first part we present the barycenter method, a technique which has been introduced by G. Besson, G. Courtois and S. Gallot in 1995, in order to solve the Minimal Entropy conjecture. In Chapter 1 we are interested in the more recent developments of this method, more precisely in the recent extension of the method to the case of manifolds having sectional curvature of variable sign. In Chapters 2 and 3 we shall present some new results whose proofs make use of the barycenter method. The Conjugacy Rigidity problem is the theme of Chapter 2. First we show a general result which provide a comparison between the large scale geometry of the Riemannian universal coverings of two compact manifolds whose geodesic flows are conjugates. Then we shall show how we can apply the latter result and the barycenter method in curvature of variable sign in order to give a new proof of the conjugacy rigidity of flat manifolds. In Chapter 3 we shall give a proof of a spectra comparison theorem for a compact Riemannian manifold which admits a Gromov-Hausdorff-approximation of non zero absolute degree on a fixed compact manifold (X,g') and which has volume almost smaller than the one of the reference manifold. The proof relies on the barycenter method in curvature of variable sign and on iterated Sobolev inequalities. We underline that it is an approximation result (and not just a convergence result) and that no curvature assumptions are made or inferred on (Y,g). The second part of the Thesis consists of a single chapter. In this chapter we prove a Margulis Lemma without curvature assumptions for Riemannian manifolds having decomposable 2-torsionless fundamental group. We shall give also a proof of a universal lower bound for the homotopy systole of compact Riemannian manifolds having bounded volume entropy and diameter, and decomposable torsionless fundamental group. As a consequence of the latter result we shall deduce a Precompactness and Finiteness theorem and a Volume estimate without curvature assumptions

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Altes, Talissa A. „Minimum delay packet length“. Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/15090.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaf 61.
by Talissa A. Altes.
M.S.

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Maunder, Robert G. „Irregular variable length coding“. Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/264980/.

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In this thesis, we introduce Irregular Variable Length Coding (IrVLC) and investigate its applications, characteristics and performance in the context of digital multimedia broadcast telecommunications. During IrVLC encoding, the multimedia signal is represented using a sequence of concatenated binary codewords. These are selected from a codebook, comprising a number of codewords, which, in turn, comprise various numbers of bits. However, during IrVLC encoding, the multimedia signal is decomposed into particular fractions, each of which is represented using a different codebook. This is in contrast to regular Variable Length Coding (VLC), in which the entire multimedia signal is encoded using the same codebook. The application of IrVLCs to joint source and channel coding is investigated in the context of a video transmission scheme. Our novel video codec represents the video signal using tessellations of Variable-Dimension Vector Quantisation (VDVQ) tiles. These are selected from a codebook, comprising a number of tiles having various dimensions. The selected tessellation of VDVQ tiles is signalled using a corresponding sequence of concatenated codewords from a Variable Length Error Correction (VLEC) codebook. This VLEC codebook represents a specific joint source and channel coding case of VLCs, which facilitates both compression and error correction. However, during video encoding, only particular combinations of the VDVQ tiles will perfectly tessellate, owing to their various dimensions. As a result, only particular sub-sets of the VDVQ codebook and, hence, of the VLEC codebook may be employed to convey particular fractions of the video signal. Therefore, our novel video codec can be said to employ IrVLCs. The employment of IrVLCs to facilitate Unequal Error Protection (UEP) is also demonstrated. This may be applied when various fractions of the source signal have different error sensitivities, as is typical in audio, speech, image and video signals, for example. Here, different VLEC codebooks having appropriately selected error correction capabilities may be employed to encode the particular fractions of the source signal. This approach may be expected to yield a higher reconstruction quality than equal protection in cases where the various fractions of the source signal have different error sensitivities. Finally, this thesis investigates the application of IrVLCs to near-capacity operation using EXtrinsic Information Transfer (EXIT) chart analysis. Here, a number of component VLEC codebooks having different inverted EXIT functions are employed to encode particular fractions of the source symbol frame. We show that the composite inverted IrVLC EXIT function may be obtained as a weighted average of the inverted component VLC EXIT functions. Additionally, EXIT chart matching is employed to shape the inverted IrVLC EXIT function to match the EXIT function of a serially concatenated inner channel code, creating a narrow but still open EXIT chart tunnel. In this way, iterative decoding convergence to an infinitesimally low probability of error is facilitated at near-capacity channel SNRs.

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Saunders, Bryan James. „Semigroups with length morphisms“. Thesis, University of St Andrews, 1998. http://hdl.handle.net/10023/13706.

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The class of metrical semigroups is defined as the set consisting of those semigroups which can be homomorphically mapped into the semigroup of natural numbers (without zero) under addition. The finitely generated members of this class are characterised and the infinitely generated case is discussed. A semigroup is called locally metrical if every finitely generated subsemigroup is metrical. The classical Green's relations are trivial on any metrical semigroup. Generalisations H⁺,L⁺ and R⁺ of the Green's relations are defined and it is shown that for any cancellative metrical semigroup, S, H⁺ is " as big as possible " if and only if S is isomorphic to a special type of semidirect product of N and a group. Lyndon's characterisation of free groups by length functions is discussed andalink between length functions, metrical semigroups and semigroups embeddable into free semigroups is investigated. Next the maximal locally metrical ideal of a semigroup is discussed, and the class of t-compressible semigroups is defined as the set consisting of those semigroups that have no locally metrical ideal. The class of t-compressible semigroups is seen to contain the classes of regular and simple semigroups. Finally it is shown that a large class of semigroups can be decomposed into a chain of locally metrical ideals together with a t-compressible semigroup.

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Francis, Robert Alan. „Characterising hyperbolicity in length spaces“. Thesis, University of Southampton, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509475.

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40

Morrow, Edward Hugh. „The evolution of sperm length“. Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367026.

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Kedziora, Sylwia Maria. „How Rif1 controls telomere length“. Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=235993.

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The activation of replication origins is temporally regulated in S phase, with some origins activating early and some late. The molecular events controlling the temporal programme are not well understood, but in S. cerevisiae there is a close relationship between telomere length and nearby origin activation time. In the first part of this thesis I explore how the initiation time of origins near to telomeres is regulated by telomere length in a manner dependent on the Tel1 kinase. I demonstrate that an induced short telomere drives early activation of a nearby origin, but that in the absence of Tel1 the same origin activates late. In the second, major part of this thesis I focus on how the Rif1 protein negatively regulates length of the terminal TG1-3 repeats. While Rif1 has long been known to control telomere length, the mechanism through which Rif1 prevents telomere over-extension has remained unclear. Recently Rif1 was discovered to act in DNA replication control as a Protein Phosphatase 1-targeting subunit, directing Protein Phosphatase 1 (PP1) to dephosphorylate the MCM replicative helicase complex. I therefore investigated whether Rif1 also controls telomere length through PP1 interaction. I examine the effects of a mutant Rif1 with its PP1 interaction sites mutated to ablate PP1 binding. I found the mutant Rif1 binds normally to telomeres but causes a long telomere phenotype, similar to that in ∆rif1 cells, implicating Rif1-PP1 interaction in telomere length control. In further experiments I show that tethered PP1 can partially substitute for Rif1 in telomere length control. I also establish that the effect of Rif1-PP1 on telomere length does not operate indirectly through replication timing control, but rather appears to act through a direct pathway controlling telomerase recruitment. I discuss potential dephosphorylation targets, and the mechanism through which Rif1 and PP1 may control telomere length homeostasis. To summarise, my PhD research demonstrates that S. cerevisiae Rif1 acts with PP1 to repress telomerase-mediated TG1-3 repeat extension.

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Pooley, Karen Anne. „Genetic factors in telomere length“. Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609670.

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43

Neal, Jeremy L. „Physiological Factors Influencing Labor Length“. The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1218220309.

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44

Ballinger, Brad. „Length-preserving transformations on polygons /“. For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.

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Routray, Sudhir Kumar. „Statistical analysis and modeling of optical transport networks“. Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14272.

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Doutoramento em Telecomunicações
Statistical analysis and modeling of networks is now an integral part of network science and engineering. In case of optical transport networks (OTNs), it can be used for the planning and dimensioning when the complete information is not available or is difficult to process. The core networks around the world today are almost optical and they form the backbone of the Internet. Therefore, the statistical characteristics of these networks must be studied to understand their nature and to estimate their parameters. In science and technology, network analysis and modeling are used for several purposes such as the analysis of their stability, reliability and long term evolution. Knowledge of the statistical models helps in the estimation of several critical parameters of the networks. The work presented in this thesis is focused on the analysis and modeling of link lengths and shortest path lengths in OTNs. The parameters used in the models presented in this thesis can be estimated from the very basic information of the networks such as the coverage area and the number of nodes, both of which can be found from the node locations. These models can be applied to estimate key parameters of the networks. In this thesis, we have shown that the link lengths of the OTNs follow general extreme value distribution. The parameters of the proposed distribution can be estimated from the average link lengths of the networks. We develop expressions for the average link lengths of OTNs which can be estimated with an average error of just 11%. We apply the developed model to estimate link length dependent parameters in OTNs. We show that the shortest path lengths of the OTNs follow Johnson SB distribution. We estimate the parameters of the developed model from the convex area and the number of nodes of the network. We also apply this model to estimate several shortest path-dependent parameters in OTNs.
A análise estatística e modelação de redes é atualmente uma parte integrante da ciência e engenharia de redes. No caso das redes óticas de transporte (OTN), a modelação estatistica pode ser usada para o planeamento e dimensionamento quando a informação completa não está disponível ou o seu processamento é muito demorado. As redes óticas constituem atualmente o núcleo central das redes que suportam a Internet. Portanto, as características estatísticas dessas redes devem ser estudadas por forma a compreender sua natureza e estimar os seus parâmetros. Em ciência e tecnologia, a análise e modelação de redes é usada para vários fins, tais como análise de estabilidade, fiabilidade e evolução a longo prazo. O conhecimento dos modelos estatísticos ajuda na estimativa de vários parâmetros críticos das redes. O trabalho apresentado nesta tese está focado na análise e modelação dos comprimentos das ligaçães e dos caminhos mais curtos em OTN. Os parâmetros usados nos modelos apresentados nesta tese podem ser estimados a partir de informação muito simples das redes, tais como a sua área de cobertura e o número de nós, sendo que ambas podem ser obtidas a partir da localização dos nós. Estes modelos podem ser aplicados para estimar parâmetros-chave das redes. Nesta tese, demonstramos que o comprimento dos ligações em OTN segue uma distribuição do tipo general extreme value. Os parâmetros da distribuição podem ser estimados a partir do comprimento médio das ligações. Por sua vez mostramos que o comprimento médio das ligações pode ser estimado com um erro médio de 11% sendo apenas conhecida a área de cobertura da rede. Mostramos como é possivel aplicar o modelo desenvolvido à estimação de parâmetros dependentes do comprimento das ligações. Mostramos também que o comprimento dos caminhos mais curtos segue uma distribuição do tipo Johnson SB. Os parâmetros usados neste modelo podem ser estimados a partir da área convexa e do número de nós da rede. Aplicamos ainda este modelo para estimar diversos parâmetros dependentes do caminho mais curto.

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Christensen, My, und Johanna Pihlgren. „Typografiska riktlinjer och textframställning för smartphones“. Thesis, Högskolan Dalarna, Grafisk teknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:du-10724.

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Idag använder allt fler människor sina smartphones för att surfa och använda tjänster online. Detta innebär att en stor del text läses på små skärmar. Detta arbete handlar om hur text bäst utformas och struktureras för att enklast kunna läsas och uppfattas på en mobilskärm. Faktorer som berörs är typgrad, ljusrum, textlängd, teckensnittsklass, radlängd, bild i text och kontrastverkan. Arbetet utgår från en normativ, svensk person utan funktionsnedsättningar. Arbetet är grundat på litteratur, egna analyser, intervjuer med branschfolk, enkätundersökning och test med fokusgrupp. Resultatet blev att en text på smartphone bäst utformas med flera styckesindelningar i form av blankrader, med bilder där bilden tillför något i informativt syfte och textlängd baserat på ämneskategori. Bilden bör sättas ovanför brödtexten. Längre texter ska sättas med scrollfunktion. Kontrast har stor betydelse på mobiltelefoner, texter går bra att läsa även när de är satta negativt. Teckensnittsklass är enligt resultatet av denna rapport inte av betydelse. Både seriff och sanserif kan läsas utan problem på smartphones. Typgraden bör förstoras något i förhållande till telefonens default-inställningar. På grund av att text på skärm inte stödjer avstavningar rekommenderas korta ord där det är möjligt för att förhindra en allt för hackig högerkant.
This research focuses on the issue of how to best structure text on a Smartphone screen. The factors involved in this research are text size, white space, text and line lengths, serif and sans serif fonts, pictures in text and contrast. The methodology of our research is based on a normative Swedish able-bodied person, as well as on relevant literature, personal analyses, interviews with people in the trade, an online survey, and a test performed with a focus group. The results are that a text written for Smartphones is best structured with: several paragraph divisions made with blank lines, with pictures where the picture has an informational purpose, and text length based on category of subject. The picture should be placed above the body text. Longer texts should be set with a scroll-function. Contrast is of great importance on mobile phones as texts can be read properly even when set in negative. In addition, using serif or sans serif is of no importance. According to the results both serif and sans serif can be read without difficulties on a Smartphone. Text size should be slightly enlarged in relation to the default settings on the mobile device. Since word division is not supported on screen, short words are recommended when possible to prevent a highly uneven right end.

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Lenart, Joshua Bela. „Burdens and Blessings heuristic pedagogy for the rhetorical endeavor in composition /“. Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/lenart/LenartJ0505.pdf.

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Frizzarin, Rejane Mara. „Desenvolvimento de procedimentos analíticos em fluxo explorando difusão gasosa ou extração em ponto de nuvem. Aplicação a amostras de interesse agronômico e ambiental“. Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-30032015-160404/.

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Procedimentos analíticos espectrofotométricos foram desenvolvidos empregando etapas de separação e pré-concentração em sistemas de análises em fluxo com multi-impulsão ou lab-in-syringe, com aplicação a amostras de interesse agronômico (ferro em materiais vegetais e alimentos) e ambiental (cianeto dissociável em ácidos, ferro e antimônio em águas). A determinação de cianeto explorou a descoloração do complexo formado entre Cu(I) e ácido 2-2´-biquinolino-4,4´-dicarboxílico (BQA) pela presença de CN-, após a separação de HCN por difusão gasosa. Espectrofotometria com longo caminho óptico foi empregada para aumentar a sensibilidade, com resposta linear entre 5 e 200 g L-1, limite de detecção, coeficiente de variação (n = 10) e frequência de amostragem de 2,0 g L-1, 1,5% e 22 h-1, respectivamente. O procedimento consumiu apenas 48 ng de Cu(II), 5,0 g de ácido ascórbico e 0,9 g de BQA por determinação e gerou 2,6 mL de efluente. Tiocianato, nitrito e sulfito não afetaram a determinação de cianeto e peróxido de hidrogênio evitou a interferência de sulfeto até 200 g L-1. Os resultados para as amostras de águas naturais foram concordantes com o procedimento fluorimétrico em fluxo com 95% de confiança. Novas estratégias foram propostas para a extração em ponto nuvem (EPN) em fluxo: (i) a fase rica em surfactante foi retida diretamente na cela de fluxo, evitando a diluição; (ii) microbombas solenoide foram exploradas para melhorar a mistura e modular a vazão na retenção e remoção da fase rica, evitando a eluição com solvente orgânico e (iii) o calor liberado e os sais fornecidos por uma reação de neutralização em linha foram explorados para indução do ponto nuvem, sem dispositivo externo de aquecimento. Estas inovações foram demonstradas pela determinação espectrofotométrica de ferro baseada no complexo com 1-(2-tiazolilazo)-2-naftol (TAN). Resposta linear foi observada entre 10 e 200 g L-1, com limite de detecção, coeficiente de variação e frequência de amostragem de 5 g L-1, 2,3% (n = 7) e 26 h-1, respectivamente. O fator de enriquecimento foi de 8,9 com consumo apenas de 6 g de TAN e 390 g de Triton X-114 por determinação. Os resultados para amostras de águas foram concordantes com o procedimento de referência e os obtidos para digeridos de materiais de referência de alimentos concordaram com os valores certificados. A determinação espectrofotométrica de antimônio foi realizada explorando pela primeira vez a EPN em sistema lab-in-syringe. O complexo iodeto e antimônio forma um par iônico com H+, que pode ser extraído com Triton X-114. Planejamento fatorial demonstrou que as concentrações de ácido ascórbico, H2SO4 e Triton X-114, bem como as interações de segunda e de terceira ordem foram significativas (95% de confiança). Planejamento Box-Behnken foi aplicado para a identificação dos valores críticos. Robustez com 95% de confiança, resposta linear entre 5 e 50 g L-1, limite de detecção, coeficiente de variação (n = 5) e frequência de amostragem foram estimados em 1,8 g L-1, 1,6% e 16 h-1, respectivamente. Os resultados para amostras de águas naturais e medicamentos anti-leishmaniose foram concordantes com os obtidos por espectrometria de absorção atômica com geração de hidretos (HGFAAS) com 95% de confiança
Spectrophotometric analytical procedures were developed by exploiting separation and preconcentration steps in flow systems based on multi-pumping or lab-in-syringe approaches with application to agronomic (iron in plant materials and food) and environmental samples (acid dissociable cyanide, iron and antimony in waters). Cyanide determination exploited bleaching of the Cu(I)/2,2\'-biquinoline 4,4\'-dicarboxylic acid (BCA) complex by the analyte, after separation of HCN by gas diffusion. Long path length spectrophotometry was successfully exploited to increase sensitivity, thus achieving a linear response from 5 to 200 g L-1, with detection limit, coefficient of variation (n = 10) and sampling rate of 2 g L-1, 1.5% and 22 h-1, respectively. Each determination consumed 48 ng of Cu(II), 5 g of ascorbic acid and 0.9 g of BCA. As high as 100 mg L-1 thiocyanate, nitrite or sulfite did not affect cyanide determination and sample pretreatment with hydrogen peroxide avoided sulfide interference up to 200 g L-1. The procedure is environmentally friendly and presented one of the lowest detection limits associated to high sampling rate. The results for freshwater samples agreed with those obtained with the flow-based fluorimetric procedure at the 95% confidence level. Novel strategies were proposed for on-line cloud point extraction (CPE): (i) the surfactant-rich phase was retained directly into the flow cell to avoid dilution prior to detection; (ii) solenoid micro-pumps were explored to improve mixing and for flow modulation in the retention and removal of the surfactant-rich phase, thus avoiding the elution step with organic solvents and (iii) the heat released and the salts provided by an on-line neutralization reaction were exploited to induce cloud point without an external heating device. These approaches were demonstrated for the spectrophotometric determination of iron based on complex formation with 1-(2-thiazolylazo)-2-naphtol (TAN). A linear response was observed from 10 to 200 g L-1, with detection limit, coefficient of variation, and sampling rate of 5 g L-1, 2.3% (n = 7) and 26 h-1, respectively. The enrichment factor was 8.9 and the procedure consumed only 6 g of TAN and 390 g of Triton X-114 per determination. The results for freshwater samples agreed with the reference procedure and those obtained for certified reference materials of food agreed with the certified values. Spectrophotometric determination of antimony was performed for the first time exploiting CPE in the lab-in-syringe system. The antimony/iodide complex forms an ion-pair with H+, which can be extracted with Triton X-114. Factorial design showed that the concentrations of ascorbic acid, H2SO4 and Triton X-114, as well as the second and third order interactions were significant (95% confidence). The Box-Behnken design was applied to identify the critical values. The system is robust with 95% confidence and a linear response was observed from 5 to 50 g L-1, with detection limit, coefficient of variation (n = 5) and sampling rate of 1.8 g L-1, 1.6% and 16 h-1, respectively. The results for water samples and antileishmanial drugs agreed with those obtained by hydride generation atomic absorption spectrometry at the 95% confidence level

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Trent, Justin David. „Transfer Length, Development Length, Flexural Strength, and Prestress Loss Evaluation in Pretensioned Self-Consolidating Concrete Members“. Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/33161.

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The first objective of this thesis was to determine the effect of using self-consolidating concrete versus normal concrete on transfer and development lengths, and flexural strengths of prestressed members. Three small rectangular members were made, two cast with SCC mixes and one cast with a conventional mix, to determine the transfer length of each mix. Transfer lengths of both ends of each member were determined by measuring the concrete surface strains. The change in the transfer length was monitored by determining the transfer length of each member at prestress release, 7 days after release, and 28 days after release. All concrete mixes had lower than code determined transfer lengths at prestress release. Each concrete mix showed between a 12 to 56 percent increase in transfer length after 28 days. One SCC mix exceeded the ACI code stipulated 50 strand diameters 7 days after prestress transfer. The other SCC mix was consistently below the transfer length of the conventional concrete.

Separate development length members were cast in a stay-in-place steel form used for creating structural double tees. Each development length member was a stub tee. Iterative load testing was performed to determine the development length of each SCC and conventional mix. Development lengths for both SCC mixes were approximately 20 percent shorter than ACI and AASHTO code predictions. A development length for the conventional concrete was not determined due to non-repeating test data. The flexural strength of each member was determined during load testing. All concrete mixes achieved higher than the ACI predicted strengths.

The second objective of this thesis was to experimentally measure prestress losses and compare these experimental values to theoretical models. Crack initiation and crack reopening tests were performed to experimentally determine the prestress losses in each member. Three theoretical models were evaluated, the sixth edition PCI Design Handbook suggested model, a 1975 PCI Committee on Prestress Losses model, and the AASHTO LRFD prestress loss model. The crack initiation experimental values tended to be between 10 and 15 percent lower than theoretical models. In general, the crack reopening prediction of the effective prestress had a good correlation with theoretical models. This suggests crack reopening tests can be used as predictors of effective prestress, and as such, predictors of prestress losses in future experimental research. Additionally, the concrete type was shown to affect the prestress losses determined in the development length members. The SCC members tended to have higher effective prestress forces than the conventional concrete members, and thus had less prestress losses due to creep and shrinkage than the conventional concrete members.
Master of Science

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Sparrow, Leah M., Emily Pellatt, Sabrina S. Yu, David A. Raichlen, Herman Pontzer und Campbell Rolian. „Gait changes in a line of mice artificially selected for longer limbs“. PEERJ INC, 2017. http://hdl.handle.net/10150/623229.

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In legged terrestrial locomotion, the duration of stance phase, i.e., when limbs are in contact with the substrate, is positively correlated with limb length, and negatively correlated with the metabolic cost of transport. These relationships are well documented at the interspecific level, across a broad range of body sizes and travel speeds. However, such relationships are harder to evaluate within species (i.e., where natural selection operates), largely for practical reasons, including low population variance in limb length, and the presence of confounding factors such as body mass, or training. Here, we compared spatiotemporal kinematics of gait in Longshanks, a long-legged mouse line created through artificial selection, and in random-bred, mass-matched Control mice raised under identical conditions. We used a gait treadmill to test the hypothesis that Longshanks have longer stance phases and stride lengths, and decreased stride frequencies in both fore- and hind limbs, compared with Controls. Our results indicate that gait differs significantly between the two groups. Specifically, and as hypothesized, stance duration and stride length are 8–10% greater in Longshanks, while stride frequency is 8% lower than in Controls. However, there was no difference in the touch-down timing and sequence of the paws between the two lines. Taken together, these data suggest that, for a given speed, Longshanks mice take significantly fewer, longer steps to cover the same distance or running time compared to Controls, with important implications for other measures of variation among individuals in whole-organism performance, such as the metabolic cost of transport.

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Dissertationen zum Thema „Lenght“

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