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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Block-based Bayesian Decision Feedback Equalization for ZP-OFDM Systems with Semi-Blind Channel Estimation

Bai, Yun-kai 25 August 2007 (has links)
Orthogonal frequency division multiplexing (OFDM) modulator with redundancy has been adopted in many wireless communication systems for higher data rate transmissions. The introduced redundancy at the transmitter allows us to overcome serious inter-block interference (IBI) problems due to highly dispersive channel. However, the selection of redundancy length will affect the system performance and spectral efficiency, and is highly dependent on the length of channel impulse response. In this thesis, based on the pseudorandom postfix (PRP) OFDM scheme we propose a novel block-based OFDM transceiver framework. Since in the PRP-OFDM system the PRP can be employed for semi-blind channel estimation with order-one statistics of the received signal. Hence, for sufficient redundancy case the PRP-OFDM system with the Bayesian decision feedback equalizer (DFE) is adopted for suppressing the IBI and ISI simultaneously. However, for the insufficient redundancy case (the length of redundancy is less than the order of channel), we first propose a modified scheme for channel estimation. To further reduce the complexity of receiver, the maximum shortening signal-to-noise-ratio time domain equalizer (MSSNR TEQ) with the Bayesian DFE is developed for suppressing the IBI and ISI, separately. That is, after knowing the channel state information (CSI) and removing the effect of IBI with MSSNR TEQ, the Bayesian DFE is applied for eliminating the ISI. Via computer simulation, we verify that performance improvement, in terms of bit error rate (BER), compared with the conventional block-based minimum mean square error (MMSE)-DFE can be achieved.
52

Cenozoic evolution of a fragmented foreland basin, Altiplano plateau, southern Peru

Fitch, Justin David 14 November 2013 (has links)
Debate persists on the timing, magnitude and style of crustal shortening, uplift and basin evolution in the Andes. Many studies suggest that the central Andes, including the Altiplano plateau, were gradually uplifted as a result of protracted Cenozoic retroarc shortening. However, recent isotopic studies conclude that the Andes instead rose in pulses, with the most significant event occurring at 10-6 Ma. Many researchers attribute these rapid pulses of uplift to lower lithosphere delamination events. A better understanding of the history of Cenozoic crustal shortening is essential for determination of the mechanism(s) of Andean uplift. The well-exposed Cenozoic San Jerónimo Group was studied in the Ayaviri basin of the northern Altiplano in southern Peru. The 3-5 km-thick succession is situated at 3900-4800 m elevation, between the Western Cordillera magmatic arc and the Eastern Cordillera fold-thrust-belt. New detrital zircon U-Pb geochronological results from four sandstones and one reworked tuff in the San Jerónimo succession show large age populations indicative of syndepositional volcanism between approximately 38 and 27 Ma. A 1600-m-thick magnetostratigraphic section further constrains the depositional timing and accumulation rate of the upper portion of the succession. Sedimentological observations show a rapid transition from cross-stratified braided-fluvial sandstones to proximal channel-fill and alluvial-fan conglomerates at ~30 Ma. Paleocurrent measurements show important temporal and spatial variations in sediment dispersal patterns while conglomerate clast counts show an upsection transition from almost exclusively volcanic input to increasing contributions of clastic, quartzite, and limestone detritus. The corresponding shifts in depositional environment and sediment provenance are attributed to the activation of new thrust structures in close proximity to the basin, namely the Pucapuca-Sorapata fault system, indicating the presence of an eastward advancing fold-thrust belt dating to at least 38 Ma and reaching the Ayaviri basin within the northern Altiplano plateau at ~30 Ma. / text
53

Estrutura e função osteomuscular, capacidade funcional e qualidade de vida de idosas em resposta a um modelo de treinamento fundamentado no princípio de ação do ciclo alongamento-encurtamento / Structure and musculoskeletal function, functional capacity and quality of life of elderly women in response to a training model based on the stretch-shortening cycle

João Pedro dos Santos Ferreira Moreira de Pinho 09 June 2016 (has links)
Introdução: o processo fisiológico de envelhecimento traduz-se em diversas alterações estruturais do sistema musculoesquelético. Estas, por sua vez, acarretam em modificações funcionais que se repercutem na dependência do senescente, determinando a diminuição da sua qualidade de vida. Das estratégias existentes para atenuar os efeitos da senescência o treinamento de potência tem sido apontado como preferido. Existem, contudo, indícios de que um treinamento baseado na potencialização da ação do ciclo alongamento-encurtamento seja uma melhor escolha. Hipóteses do estudo: pelos resultados obtidos em intervenções similares, hipotetiza-se que as participantes do protocolo de intervenção proposto apresentarão um aumento da densidade mineral óssea, do volume muscular, da capacidade funcional e melhora de alguns parâmetros biomecânicos da marcha, bem como da sua qualidade de vida. Objetivos: o objetivo geral do presente trabalho é, portanto, propor um modelo de treinamento fundamentado na potencialização da ação do ciclo alongamento-encurtamento e averiguar os seus efeitos em parâmetros selecionados da morfologia osteomuscular, capacidade funcional e qualidade de vida de idosas. Materiais e Métodos: 21 idosas sedentárias (66,9±4,2 anos) executaram o protocolo proposto durante 20 semanas, tendo os efeitos na densidade mineral óssea de fêmur, coluna, tíbia e rádio; efeitos na composição corporal, na força, no equilíbrio, na marcha, na flexibilidade e na qualidade de vida comparados aos efeitos obtidos pelo grupo controle (N=17, 65,0±3,4 anos), que não alterou o seu nível de atividade física. O protocolo de intervenção, composto por onze exercícios de força realizados com o intuito de potencializar a ação do ciclo alongamento-encurtamento, que apresentava duas modalidades de salto (salto vertical com contramovimento e drop jump), exigia a realização da fase concêntrica na maior velocidade possível. Resultados: quando comparado com o grupo controle, o grupo experimental apresentou alterações significantes (p<0,05) na densidade mineral óssea de coluna (g=1,06) e sua microarquitetura (g=0,80), na microarquitetura da tíbia (g=0,82), na força máxima (g=2,39) e potência (g=1,38) de extensores de joelho, na velocidade máxima de marcha (g=0,96), na flexibilidade de membros inferiores (g=1,05) e superiores (g=0,86) e no domínio Atividades passadas, presentes e futuras da qualidade de vida (g=1,08). Conclusão: os resultados apontam para a eficácia da proposta de intervenção, apresentando-se como uma nova estratégia para atenuar e até mesmo reverter algumas perdas estruturais e funcionais impostas pelo processo de envelhecimento / Introduction: the physiological aging process induces several structural changes in the musculoskeletal system. These, in turn, result in functional changes that are reflected in the senescent dependency, determining the reduction in their quality of life. Power training has been identified as ideal to mitigate the effects of aging. However, there are indications that an intervention based on the potentiation of the stretch-shortening cycle action is a better choice. Study hypotheses: the participants of the proposed intervention will increase their bone mineral density, muscle volume, functional capacity and will show some improvement in their gait, as well as in their quality of life. Purposes: the main objective of this study was to propose a training model based in the potentiation of the stretch-shortening cycle action and assess its effects on selected parameters of musculoskeletal morphology, functional capacity and quality of life of elderly women. Methods: 21 sendentary elderly women (66.9 ± 4.2 years) performed the proposed intervention protocol for 20 weeks and the effects on bone mineral density of the femur, spine, tibia and radio; effects on body composition, strength, balance, gait, flexibility and quality of life were compared to the effects obtained by the control group (N = 17, 65.0 ± 3.4 years) that did not change their level of physical activity. The program was composed by eleven strength exercises performed in order to enhance stretch-shortening cycle action, had two jump exercises (vertical jump with countermovement and drop jump) and had the concentric phase of the movements performed as fast as possible. Results: when compared to the control group the experimental group showed significant changes (p <0.05) in bone mineral density of the spine (g = 1.06) and its microarchitecture (g = 0.80), the microarchitecture of the tibia (g = 0.82), the knee extensors maximum force (g = 2.39) and power (g = 1.38), the maximum walking speed (g = 0.96), the lower (g = 1.05) and upper (g = 0.86) limbs flexibility and in the domain past, present and future activities of the quality of life (g = 1.08). Conclusion: the results point to the effectiveness of the proposed intervention, suggesting it as a new strategy to slow down and even reverse some structural and functional losses imposed by the aging process
54

Folheações riemannianas e geodésicas fechadas em orbifolds

Souza, Cristiano Augusto de 04 March 2016 (has links)
Submitted by Caroline Periotto (carol@ufscar.br) on 2016-10-03T20:28:29Z No. of bitstreams: 1 DissCASfr.pdf: 1220679 bytes, checksum: 34316f04f7e4dda72c5fb929a51099d8 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T19:18:17Z (GMT) No. of bitstreams: 1 DissCASfr.pdf: 1220679 bytes, checksum: 34316f04f7e4dda72c5fb929a51099d8 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T19:18:22Z (GMT) No. of bitstreams: 1 DissCASfr.pdf: 1220679 bytes, checksum: 34316f04f7e4dda72c5fb929a51099d8 (MD5) / Made available in DSpace on 2016-10-20T19:18:28Z (GMT). No. of bitstreams: 1 DissCASfr.pdf: 1220679 bytes, checksum: 34316f04f7e4dda72c5fb929a51099d8 (MD5) Previous issue date: 2016-03-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The present thesis is devoted to the study of closed geodesics in some types of orbifolds. First, we present the notion of Riemannian foliation and their equivalent definitions using foliation atlas and Riemannian submersions. Aiming to understand the leaf space of certain foliations, we introduce the concept of orbifold. Also, the notion of orbifolds will be addressed via pseudogroups. For compact Riemannian good orbifolds, we will prove the existence of non-trivial closed geodesics. The main objective of this work is to obtain closed geodesics in compact Riemannian orbifolds by employing the shortening process with respect to Riemannian foliations. Following the approach of Alexandrino and Javaloyes [5], we also discuss the existence of closed geodesics in the leaf spaces for some classes of singular Riemannian foliations. / A presente dissertação é devotada ao estudo de geodésicas fechadas em alguns tipos de orbifolds. Primeiro, é apresentada a noção de folheação Riemanniana bem como suas equivalentes definições via atlas folheados e submersões Riemannianas. Visando compreender o espaço das folhas de certas folheações, é introduzido o conceito de orbifold. Também será abordada a noção de orbifolds via pseudogrupos. Para orbifolds riemannianos compactos bons, é provada a existência de geodésicas fechadas de comprimento positivo. O principal objetivo deste trabalho é empregar o processo de encurtamento com relação às folheações Riemannianas para obter geodésicas fechadas em orbifolds riemannianos compactos. Seguindo a abordagem de Alexandrino e Javaloyes [5], também discutimos sobre a existência de geodésicas fechadas no espaço das folhas de algumas classes de folheações Riemannianas singulares.
55

Nové ultrazvukové markery aneuploidií v prvém trimestru gravidity / New Aneuploidy Ultrasound Markers in First Trimester of Pregnancy

Břešťák, Miroslav January 2015 (has links)
Prenatal diagnostics is headed in several directions - towards visualization of fetuses and biochemical, cytogenetic and molecular genetic diagnostics in laboratories. Whereas visualization of fetuses does not a priori represent any direct risk for pregnancy and does not increase the number of potential pregnancy complications, this is not always the case with the laboratory testing. There are known risks connected with invasive methods of prenatal diagnostics. The number of potential unintentional pregnancy complications and losses as well as the technical and economic aspects of invasive prenatal diagnostics lead to attempts of identifying ways of detecting any potentially affected individuals by screening methods, thus minimizing the undesirable impact of invasive diagnostics on the pregnant population. The more precise the selective criteria, the lesser the number of pregnant women exposed to invasive exams. Another way of decreasing the number of unintentional complications in relation to invasive diagnostics is to simplify and improve the fetal samples harvesting methods during pregnancy. The work primarily focused on two areas: Determination of the relation between fraction shortening of the left and right ventricles and a fetal chromosomal complement, and verification of reliability of a new method...
56

Estresse oxidativo em Leishmania amazonensis = do encurtamento dos telômeros ao deslocamento de LaRPA-1 do complexo telomérico = Oxidative stress in Leishmania amazonensis : from telomere shortening to displacement of LaRPA-1 from telomeric complex / Oxidative stress in Leishmania amazonensis : from telomere shortening to displacement of LaRPA-1 from telomeric complex

Da Silva, Marcelo Santos, 1982- 26 August 2018 (has links)
Orientador: Maria Isabel Nogueira Cano / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T06:26:57Z (GMT). No. of bitstreams: 1 DaSilva_MarceloSantos_D.pdf: 9189361 bytes, checksum: 79ecad917f6be7c8b200b549dafc493e (MD5) Previous issue date: 2014 / Resumo: A leishmaniose é um espectro de doenças causadas por parasitos do gênero Leishmania, que afeta milhões de pessoas em todo o mundo. Durante a infecção, os parasitos usam diferentes estratégias para sobreviver as defesas do hospedeiro, incluindo superar a exposição intensa a espécies reativas de oxigênio (ROS), principais responsáveis por causar danos no DNA, sobretudo nos telômeros, induzindo instabilidade genômica, senescência e morte celular. Telômeros são estruturas nos terminais dos cromossomos compostos por sequências de DNA repetitivas e proteínas, cuja função é proteger as extremidades dos cromossomos, evitando fusões terminais e degradação nucleolítica. Neste trabalho nós induzimos estresse oxidativo agudo em formas promastigotas de L. amazonensis através do tratamento com 2 mM de peróxido de hidrogênio (H2O2) por 1h, o qual foi capaz de aumentar os níveis de ROS intracelular, como demonstrado pela reação utilizando CM-H2DCFDA. Além disso, o estresse oxidativo induziu danos no DNA, como mostrado por análise quantitativa de 8-oxodG e núcleos positivos para o ensaio TUNEL. Observamos também, através de parâmetros qualitativos e quantitativos (Southern blot, telomere-PCR e flow-FISH), que o estresse oxidativo, assim como em mamíferos, induziu encurtamento dos telômeros. Analisando a co-localização e interação proteína:DNA por FISH-IIF e ensaios ChIP, foi possível demostrar que o estresse oxidativo causou erosão da extremidade 3¿G overhang, fazendo com que a proteína LaRPA-1 perdesse seu sítio de interação nos telômeros. Além disso, pudemos observar uma maior afinidade de LaRPA-1 para com a fita telomérica rica em C, nesse caso uma região de simples-fita gerada dentro da dupla fita telomérica, provavelmente como consequência do reparo de DNA, sugerindo a participação de LaRPA-1 na resposta a danos oxidativos. Por análise de curvas de crescimento e incorporação de EdU, foi possível observar que o estresse oxidativo induziu diminuição acentuada no número de parasitos em cultura, enquanto os sobreviventes continuaram proliferando e replicando DNA. Observamos também que o estresse oxidativo agudo provocou arrest de ciclo celular na fase G2/M em parte da população em crescimento exponencial. Em conjunto, esses resultados sugerem a presença de um sistema muito eficiente de resposta a danos oxidativos no DNA telomérico, que permite que os parasitos sobrevivam e repliquem DNA mesmo após um estresse agudo / Abstract: Leishmaniasis is a spectrum of diseases caused by parasites of the genus Leishmania that affects million people around the world. During infection, parasites use different strategies to survive host defenses including overcoming exposure to Reactive Oxygen Species (ROS), mainly responsible for causing DNA damage, especially at telomeres which frequently results in genome instability, senescence and cell death. Telomeres are chromosomes end termini structures composed by repetitive DNA coupled with proteins whose function is to protect chromosome ends and avoid end-fusion and nucleolytic degradation. In this work, we induced acute oxidative stress in promastigote forms of Leishmania amazonensis by treating parasites with 2mM hydrogen peroxide (H2O2) for 1 hour, which was able to increase intracellular ROS levels, as demonstrated by CM-H2DCFDA reaction. In addition, oxidative stress induced DNA damage, as confirmed by quantitative analysis of 8-oxodG and TUNEL-positive nuclei. We have also observed using qualitative and quantitative parameters (Southern blot, telomere-PCR and flow-FISH) that oxidative stress, as in mammals, induced telomere shortening. Analysing the protein:DNA co-localization and interaction by FISH-IIF and ChIP assays, it was possible to show that oxidative stress is able to induce erosion of the 3¿G overhang, inducing a displacement of LaRPA-1 from its telomeric interaction site. In addition, we observed an increase in the affinity between LaRPA-1 and the telomeric C-rich strand, in this case, a single-strand region inside the double-strand telomeric DNA generated probably as a consequence of DNA repair, suggesting the participation of LaRPA-1 in oxidative DNA damage response. Analysis of growth curves and EdU incorporation showed that oxidative stress induced a decrease in the number of parasites in culture, while the survivors continued proliferating and replicating DNA. Moreover, as result of acute oxidative stress, part of the parasites in exponential growth shows a G2/M cell cycle arrest. Taken together, these results suggest the presence of a very efficient oxidative damage response in the telomeres that allows parasites to survive and to replicate DNA even after acute stress / Doutorado / Genetica de Microorganismos / Doutor em Genetica e Biologia Molecular
57

Analytical properties of viscosity solutions for integro-differential equations : image visualization and restoration by curvature motions / Propriétés analytiques des solutions de viscosité des équations integro-différentielles : visualisation et restauration d'images par mouvements de courbure

Ciomaga, Adina 29 April 2011 (has links)
Le manuscrit est constitué de deux parties indépendantes.Propriétés des Solutions de Viscosité des Equations Integro-Différentielles.Nous considérons des équations intégro-différentielles elliptiques et paraboliques non-linéaires (EID), où les termes non-locaux sont associés à des processus de Lévy. Ce travail est motivé par l'étude du Comportement en temps long des solutions de viscosité des EID, dans le cas périodique. Le résultat classique nous dit que la solution u(¢, t ) du problème de Dirichlet pour EID se comporte comme ?t Åv(x)Åo(1) quand t !1, où v est la solution du problème ergodique stationaire qui correspond à une unique constante ergodique ?.En général, l'étude du comportement asymptotique est basé sur deux arguments: la régularité de solutions et le principe de maximumfort.Dans un premier temps, nous étudions le Principe de Maximum Fort pour les solutions de viscosité semicontinues des équations intégro-différentielles non-linéaires. Nous l'utilisons ensuite pour déduire un résultat de comparaison fort entre sous et sur-solutions des équations intégro-différentielles, qui va assurer l'unicité des solutions du problème ergodique à une constante additive près. De plus, pour des équationssuper-quadratiques le principe de maximum fort et en conséquence le comportement en temps grand exige la régularité Lipschitzienne.Dans une deuxième partie, nous établissons de nouvelles estimations Hölderiennes et Lipschitziennes pour les solutions de viscosité d'une large classe d'équations intégro-différentielles non-linéaires, par la méthode classique de Ishii-Lions. Les résultats de régularité aident de plus à la résolution du problème ergodique et sont utilisés pour fournir existence des solutions périodiques des EID.Nos résultats s'appliquent à une nouvelle classe d'équations non-locales que nous appelons équations intégro-différentielles mixtes. Ces équations sont particulièrement intéressantes, car elles sont dégénérées à la fois dans le terme local et non-local, mais leur comportement global est conduit par l'interaction locale - non-locale, par exemple la diffusion fractionnaire peut donner l'ellipticité dans une direction et la diffusion classique dans la direction orthogonale.Visualisation et Restauration d'Images par Mouvements de CourbureLe rôle de la courbure dans la perception visuelle remonte à 1954, et on le doit à Attneave. Des arguments neurologiques expliquent que le cerveau humain ne pourrait pas possiblement utiliser toutes les informations fournies par des états de simulation. Mais en réalité on enregistre des régions où la couleur change brusquement (des contours) et en outre les angles et les extremas de courbure. Pourtant, un calcul direct de courbures sur une image est impossible. Nous montrons comment les courbures peuvent être précisément évaluées, à résolution sous-pixelique par un calcul sur les lignes de niveau après leur lissage indépendant.Pour cela, nous construisons un algorithme que nous appelons Level Lines (Affine) Shortening, simulant une évolution sous-pixelique d'une image par mouvement de courbure moyenne ou affine. Aussi bien dans le cadre analytique que numérique, LLS (respectivement LLAS) extrait toutes les lignes de niveau d'une image, lisse indépendamment et simultanément toutes ces lignes de niveau par Curve Shortening(CS) (respectivement Affine Shortening (AS)) et reconstruit une nouvelle image. Nousmontrons que LL(A)S calcule explicitement une solution de viscosité pour le le Mouvement de Courbure Moyenne (respectivement Mouvement par Courbure Affine), ce qui donne une équivalence avec le mouvement géométrique.Basé sur le raccourcissement de lignes de niveau simultané, nous fournissons un outil de visualisation précis des courbures d'une image, que nous appelons un Microscope de Courbure d'Image. En tant que application, nous donnons quelques exemples explicatifs de visualisation et restauration d'image : du bruit, des artefacts JPEG, de l'aliasing seront atténués par un mouvement de courbure sous-pixelique / The present dissertation has two independent parts.Viscosity solutions theory for nonlinear Integro-Differential EquationsWe consider nonlinear elliptic and parabolic Partial Integro-Differential Equations (PIDES), where the nonlocal terms are associated to jump Lévy processes. The present work is motivated by the study of the Long Time Behavior of Viscosity Solutions for Nonlocal PDEs, in the periodic setting. The typical result states that the solution u(¢, t ) of the initial value problem for parabolic PIDEs behaves like ?t Å v(x) Å o(1) as t ! 1, where v is a solution of the stationary ergodic problem corresponding to the unique ergodic constant ?. In general, the study of the asymptotic behavior relies on two main ingredients: regularity of solutions and the strong maximum principle.We first establish Strong Maximum Principle results for semi-continuous viscosity solutions of fully nonlinear PIDEs. This will be used to derive Strong Comparison results of viscosity sub and super-solutions, which ensure the up to constants uniqueness of solutions of the ergodic problem, and subsequently, the convergence result. Moreover, for super-quadratic equations the strong maximum principle and accordingly the large time behavior require Lipschitz regularity.We then give Lipschitz estimates of viscosity solutions for a large class of nonlocal equations, by the classical Ishii-Lions's method. Regularity results help in addition solving the ergodic problem and are used to provide existence of periodic solutions of PIDEs. In both cases, we deal with a new class of nonlocal equations that we term mixed integrodifferential equations. These equations are particularly interesting, as they are degenerate both in the local and nonlocal term, but their overall behavior is driven by the local-nonlocal interaction, e.g. the fractional diffusion may give the ellipticity in one direction and the classical diffusion in the complementary one.Image Visualization and Restoration by CurvatureMotionsThe role of curvatures in visual perception goes back to 1954 and is due to Attneave. It can be argued on neurological grounds that the human brain could not possible use all the information provided by states of simulation. But actually human brain registers regions where color changes abruptly (contours), and furthermore angles and peaks of curvature. Yet, a direct computation of curvatures on a raw image is impossible. We show how curvatures can be accurately estimated, at subpixel resolution, by a direct computation on level lines after their independent smoothing.To performthis programme, we build an image processing algorithm, termed Level Lines (Affine) Shortening, simulating a sub-pixel evolution of an image by mean curvature motion or by affine curvature motion. Both in the analytical and numerical framework, LL(A)S first extracts all the level lines of an image, then independently and simultaneously smooths all of its level lines by curve shortening (CS) (respectively affine shortening (AS)) and eventually reconstructs, at each time, a new image from the evolved level lines.We justify that the Level Lines Shortening computes explicitly a viscosity solution for the Mean CurvatureMotion and hence is equivalent with the clasical, geometric Curve Shortening.Based on simultaneous level lines shortening, we provide an accurate visualization tool of image curvatures, that we call an Image CurvatureMicroscope. As an application we give some illustrative examples of image visualization and restoration: noise, JPEG artifacts, and aliasing will be shown to be nicely smoothed out by the subpixel curvature motion.
58

O ciclo alongamento encurtamento realizado em alta velocidade aumenta a atividade neuromuscular durante as ações excêntricas / High velocity stretch-shortening cycles increase muscle activity during eccentric actions

Muramatsu, Lucio Vitorelli, 1985- 26 August 2018 (has links)
Orientador: Luiz Eduardo Barreto Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-26T19:59:48Z (GMT). No. of bitstreams: 1 Muramatsu_LucioVitorelli_M.pdf: 2705726 bytes, checksum: 4fa3509cfece4d833e50560b76383887 (MD5) Previous issue date: 2015 / Resumo: O objetivo do presente estudo foi investigar alterações neuromusculares e biomecânicas induzidas por diferentes velocidades de execução durante o ciclo de alongamento-encurtamento (CAE) realizado de forma contínua. Doze homens (25,0 ± 3,0 anos, 1,80 ± 0,05 m, 79,6 ± 8,8 kg e 8,0 ± 3,2% de gordura corporal) e três mulheres (29,0 ± 3,0 anos, 1,60 ± 0,06 m, 61,6 ± 2,1 kg e 17,1 ± 2,5% da gordura corporal) participaram do estudo. Os voluntários realizaram 3 protocolos com distintas velocidades de execução. O controle das velocidades foi realizado pelo tempo destinado à execução de cada CAE (Lento = 4 s, Médio = 2 s e Rápido = 1 s por ciclo). Cada protocolo consistiu de 20 repetições (CAE) com 10% de 1RM e 5 min de intervalo, realizados no exercício de extensão do joelho. Velocidade angular, aceleração angular, torque e eletromiografia de superfície (EMG) dos músculos vasto lateral, vasto medial e reto femoral foram acessadas. A execução do CAE em altas velocidades requer alta desaceleração no final das ações excêntricas (EXC) e alta aceleração no início das ações concêntricas (CON), aumentando assim o torque e a atividade EMG nesses momentos. Durante o protocolo Rápido, a atividade EMG da EXC foi maior que a CON. A maior produção de torque e atividade EMG no final da EXC potencializa o início da CON, diminuindo a atividade EMG nessa fase do movimento. Portanto, o CAE realizado com altas velocidades de execução (~160°/s) aumenta a eficiência neuromuscular no começo da CON, induzindo maior atividade EMG durante a ação EXC em comparação com a CON / Abstract: The aim of the present study was to investigate the neuromuscular and biomechanical changes induced by different speed-controlled stretch-shortening cycles (SSCs). Twelve men (24.8 ± 2.9 years, 1.80 ± 0.05 m, 79.6 ± 8.8 kg, and 8.0 ± 3.2% of body fat) and three women (29.0 ± 3.6 years, 1.60 ± 0.06 m, 61.6 ± 2.1 kg and 17.1 ± 2.5% of body fat) participated in the study. The three different speed-controlled SSCs (Slow = 4 s, Medium = 2 s and Fast = 1 s per cycle), were performed on the knee extension machine, consisting of 20 repetitions (SSCs) with 10% of 1RM and 5 min rest. Angular velocity and acceleration, torque and Surface EMG of the vastus lateralis, vastus medialis, and rectus femoris muscles were recorded. During the Fast, EMGRMS of the eccentric (ECC) phase was higher than in the concentric (CON). The acceleration, torque and EMG activity increased in the later phase of the ECC and in the early phase of the CON. Higher torque production and EMG activity in the later part of ECC potentiates the early phase of CON, decreasing EMG activity of these action. Therefore, fast SSCs (160°/s) increases neuromuscular efficiency of CON and induces higher EMG activity in ECC compared to CON / Mestrado / Biodinamica do Movimento e Esporte / Mestre em Educação Física
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Nové ultrazvukové markery aneuploidií v prvém trimestru gravidity / New Aneuploidy Ultrasound Markers in First Trimester of Pregnancy

Břešťák, Miroslav January 2015 (has links)
Prenatal diagnostics is headed in several directions - towards visualization of fetuses and biochemical, cytogenetic and molecular genetic diagnostics in laboratories. Whereas visualization of fetuses does not a priori represent any direct risk for pregnancy and does not increase the number of potential pregnancy complications, this is not always the case with the laboratory testing. There are known risks connected with invasive methods of prenatal diagnostics. The number of potential unintentional pregnancy complications and losses as well as the technical and economic aspects of invasive prenatal diagnostics lead to attempts of identifying ways of detecting any potentially affected individuals by screening methods, thus minimizing the undesirable impact of invasive diagnostics on the pregnant population. The more precise the selective criteria, the lesser the number of pregnant women exposed to invasive exams. Another way of decreasing the number of unintentional complications in relation to invasive diagnostics is to simplify and improve the fetal samples harvesting methods during pregnancy. The work primarily focused on two areas: Determination of the relation between fraction shortening of the left and right ventricles and a fetal chromosomal complement, and verification of reliability of a new method...
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Heltidsarbete som norm : Hur mängden arbetstid kan påverka jämställdheten på arbetsmarknaden i Sverige

Jensen, Carolina January 2022 (has links)
This essay examines the impact of employees' working hours on genderequality. There is a problem linked to part-time and full-time work alongwith gender equality, which leads to that significantly more women workspart-time than men do. The reason to this is partially because the welfareindustry is female-dominated and infused by part-time employment, andbecause of the uneven distribution of roles between the sexes. A new rule ofpresumption has been formulated in the Employment Protection Act(1982:80) which stipulates that all employment contracts apply for full-timework, unless agreed otherwise. The purpose of this essay is to investigate theprovision of full-time as the norm and whether an extension of workinghours will promote equality in the labor market. A shortening of workinghours is presented as another possible solution to the gender equalityproblem and after that, both possibilities get analyzed with their pros andcons and their relevant legislation. To investigate whether full-time work as a norm will improve genderequality, research results from previous full-time projects are compared. Insummary, the results of this essay show that full-time work as a norm islikely to be a successful equality tool, but previous research has shown thatsupplementary measures will then be required. Among other things, it will berequired that the government works to remove unfavorable working hoursand that the welfare professions become more sought after among men.Another important measure is to work more actively to remove the unevengender distribution around unpaid domestic and care work. This is importantbecause it is something that leads to many women not getting their lifepuzzle together and therefore choosing to work part-time instead of full-timein order to have more time to spare

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