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The Absence of Aspiration in the Era of AccountabilityMartinez, Mary R. 18 March 2016 (has links) (PDF)
Reforms early in the 21st century purported to close the achievement gap between White students and students of color, to provide accountability and transparency to taxpayers, to implement meaningful consequences for low-performing schools, and to create the workforce for the century. In this study, I investigated the effects of school reform on the lived experiences of students who graduated from high school in 2014 by inquiring into six young people’s perceptions of their schooling. I sought to better understand whether participants were aware of the existence and intent of school reforms, and how or whether their aspirations for their futures had evolved over the course of their formal schooling in concert with the expressed goals of those reforms. The data set consisted of narratives from six recent low-income male and female high school graduates of color. Analysis revealed striking similarities between their experiences despite the variety in outcomes. The narratives indicated that school reforms have had little impact on students’ lives other than to graft the go-to-college imperative, onto the young people’s inherent aspirations. Young people remained alienated from their education, and outcomes continued to adhere to racist, classist, and gendered expectations.
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Diagnostika vybraných kompetencí trenéra mládeže v atletice / Diagnosis of selected competencies of track and field coachKapcová, Michaela January 2019 (has links)
Title: Diagnosis of selected competencies of track and field coach of youth Objectives: The main aim of the thesis is to diagnose selected competences of a coach of youth athletics and to verify the hypothesis about the connection between performance and the aspiration of coaches. Methods: The thesis used qualitative methods of research and psychological testing. The qualitative methods used were testing, observation and research. Psychological testing was in the form of TATSO test. Finally, the statistical method F-test was used Results: The results of the work will be a useful source of information for the Czech Athletic Association in the development of curricula for trainers and will also be an indicator for athletic clubs, which organize youth trainers. Keywords: Athletics, coach of youth, coach competencies, TATSO test, F-test, ČAS, Czech Athletic Association, aspiration, level of aspiration
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Mechanical and Histological Characterization of Porcine Aortic Valves under Normal and Hypercholesterolemic ConditionsSider, Krista 12 December 2013 (has links)
Calcific aortic valve disease (CAVD) is associated with significant cardiovascular morbidity. While late-stage valve disease is well-described, there remains an unmet scientific need to elucidate early pathobiological processes. In CAVD, pathological differentiation of valvular interstitial cells (VICs) and lesion formation occur focally in the fibrosa layer. This VIC pathological differentiation has been shown to be influenced by matrix stiffness in vitro. However, little is known about the focal layer specific mechanical properties of the aortic valve in health and disease and how these changes in matrix moduli may influence VIC pathological differentiation in vivo. In this thesis, micropipette aspiration (MA) was shown to be capable of measuring the mechanical properties of a single layer in multilayered biomaterial or tissue such as the aortic valve, if the pipette inner diameter was less than the top layer thickness. With MA, the fibrosa of normal porcine aortic valves was significantly stiffer than the ventricularis; stiffer locations found only within the fibrosa were comparable to stiffnesses shown in vitro to be permissive to VIC pathological differentiation. Early CAVD was induced in a porcine model, which developed human-like early CAVD lesion onlays. Extracellular matrix remodeling occurred in the absence of lipid deposition, macrophages, osteoblasts, or myofibroblasts, but with significant proteoglycan-rich onlays and chondrogenic cell presence. These early onlays were softer than the collagen-rich normal fibrosa, and their proteoglycan content was positively correlated with Sox9 chondrogenic expression, suggesting that soft proteoglycan-rich matrix may be permissive to chondrogenic VIC differentiation. The findings from this thesis shed new light on early disease pathogenesis and improve the fundamental understanding of aortic valve mechanics in health and disease.
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Recherche de nouveaux agents pathogènes associés aux pneumopathies nosocomialesBousbia, Sabri 29 September 2011 (has links)
Récemment, les microbiotes pulmonaires bactériens d’un nombre très limité de patients atteints de mucoviscidose et de pneumopathies acquises sous ventilation mécanique (PAVM) ont été étudiés en utilisant l'amplification du gène 16S rDNA bactérien suivie par la construction de librairies de clones et différentes approches de séquençage. Ces études ont montré que la population microbienne de patients atteints de maladies respiratoires était plus diversifiée que prévue. Dans l'étude actuelle, nous utilisons une approche comparable pour identifier exhaustivement les agents pathogènes (bactéries, virus, et champignons) composant le microbiote pulmonaire associé aux pneumopathies développées en unités de réanimation. L'étude a inclus des patients admis en réanimation et présentant des formes de pneumopathies acquises sous ventilation mécanique (n = 106), de pneumopathies communautaires (n = 32), de pneumopathies nosocomiales sans ventilation mécanique (n = 22) et de pneumopathies d’aspiration (n = 25). Une cohorte de 25 patients admis en réanimation et ne présentant pas de symptômes de pneumopathie a été étudiée comme contrôle. Cette première partie du travail amènera ainsi à réaliser un catalogue exhaustif des agents de pneumopathies nosocomiales ; à connaître la prévalence des agents identifiés et d’identifier les co-infections fréquemment observées, et surtout à vérifier si ces agents peuvent être identifiés ou pas dans les prélèvements respiratoires profonds de patients non symptomatiques. Pour réaliser cette partie du travail, des séries de prélèvements, incluant des prélèvements de lavage broncho-alvéolaire (LBA), des prélèvements de sang et d'urine ont été étudiés. Ces prélèvements ont été testés par des moyens d’identification moléculaire moderne basés sur l’amplification de gènes conservés (gènes16S rDNA des bactéries et gène 18S rDNA des champignons) suivie par clonage et séquençage à grande échelle. D’autres pathogènes atypiques sont ciblés par des tests de PCR avec utilisation d’amorces spécifiques. Nous avons également inclus la culture, la co-culture d’amibes, la détection sérologique d'anticorps dirigés contre des agents sélectionnés et des tests d'antigène urinaire, afin de comparer ces tests de routine aux approches moléculaires. Comme résultats, les tests moléculaires nous ont permis d’identifier un vaste répertoire de 160 espèces bactériennes dont 73 n'ont jamais été précédemment rapportées à l’étiologie des pneumopathies. En outre, nous avons trouvé 37 phylotypes bactériens potentiellement nouveaux. Nous avons également identifié 24 espèces de champignons dont 6 n'ont pas été précédemment rapportées à l’étiologie des pneumopathies, 7 virus et étonnamment 6 espèces de plantes. De plus, certains agents pathogènes considérés comme typiques aux pneumopathies nosocomiales tels que Pseudomonas aeruginosa et des Streptococci ont été détectés chez les contrôles comme chez les patients. Cet étonnant résultat souligne l'existence d'un noyau de microbiote pulmonaire.Dans un deuxième travail, faisant suite aux travaux effectués dans notre laboratoire et qui ont pu mettre en évidence que 19% des pneumopathies nosocomiales étaient déterminées par des microorganismes associés aux amibes (MAAs) de l’eau préalablement ignorés ou négligés, nous avons utilisé un test d'immunofluorescence multiplexe pour tester la prévalence des anticorps contre les MAAs dans le sang de patients admis en réanimation et atteints de pneumopathies et la comparer à la prévalence au moment de l'admission. Comme résultat, nous démontrons que certains MAAs peuvent être plus fréquemment détectés après des épisodes de pneumopathies nosocomiales que lors de l’admission. En outre, la réponse immunitaire aux MAAs semble augmenter lorsque le séjour en réanimation est prolongé. Enfin, nous avons mis au point une stratégie de metagénomique pour tester les prélévements pour lesquels aucune étiologie n’a été retrouvée. [...] / Recently, bacterial microbiota from a limited number of patients with cystic fibrosis and ventilator-associated pneumonia (VAP) was studied using 16S rDNA gene amplification followed by clone libraries construction and sequencing. These studies have showed that the microbial population of patients with respiratory infections was more diverse than expected. In the current study, we use a similar approach to identify exhaustively the pathogens (bacteria, viruses, and fungi) comprising the microbiota associated with episodes of pneumonia developed in the intensive care units (ICU). Our study included patients admitted to ICUswith with episodes of ventilator-associated pneumonia (n = 106), community-acquired pneumonia (n = 32), nosocomial pneumonia without mechanical ventilation (n = 22) and aspiration pneumonia (n = 25). A cohort of 25 patients admitted to ICUs without symptoms of pneumonia were studied as controls. This first part of the work enables to prepare an exhaustive repertoire of nosocomial pneumonia pathogenes; to know the prevalence of the pathogens identified and to identify co-infections frequently observed, and especially to ascertain whether these agents can be identified or not in the respiratory samples of patients without symptoms of pneumonia. To perform this part of work, series of samples, including bronchoalveolar lavage (BAL) samples, blood samples and urine samples were collected. These samples were tested by means of modern molecular tools based on the amplification of conserved genes (bacterial 16S rDNA and fungal 18S rDNA genes), followed by highthroutput cloning and sequencing. The atypical pathogens are targeted by PCR tests using specific primers and probes. We also included culture, amoeba co-culture, serological detection of antibodies against selected agents and urinary antigen testing, to compare these routine tests to molecular approaches. Based on molecular testing, we identified a wide repertoire of 160 bacterial species of which 73 were never previously reported in pneumonia samples. Moreover, we found 37 putative new bacterial phylotypes. We also identified 24 fungal species of which 6 have not been previously reported in pneumonia, 7 viruses and surprisingly 6 plant species. Some pathogens considered being typical for ICU pneumonia such as Pseudomonas aeruginosa and Streptococcus species may be detected as commonly in controls as in pneumonia patients which strikingly highlight the existence of a core of pulmonary microbiota.In a second work, following previous works performed in our laboratory which were able to show that 19% of nosocomial pneumonia were determined by micro-organisms associated to amoebae (AAMs) previously ignored or neglected, we used a recent test based on multiplex serology to test for the prevalence of antibodies against the AAMs in the blood of patients admitted to ICU and developed episodes of pneumonia and compare it to the prevalence at the time of admission (controls). As a result, we demonstrate that some AAMs may be more frequently detected after episodes of nosocomial pneumonia than at the admission. In addition, the immune response to AAMS appears to increase when the ICU stay is prolonged.Finally, in order to explore samples for which no microbial aetiology was found, we have developed a subtractive hybridization metagenomic strategy and tested it on different clinical samples. The sensitivity of this strategy was also evaluated. We have demonstrated that our method, based on the detection of DNA and RNA of microorganisms in a single test, allows sensitive detection of different types of microorganisms.
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Estudo de polimorfismos do gene JY-1 e sua associação à produção de embriões in vivo e in vitro em doadoras da raça holandesa (Bos taurus taurus) / Study of JY-1 gene polymorphisms and their association with in vivo and in vitro embryo production in holstein donors (Bos taurus taurus)Silveira, Cecília Rodrigues Alves [UNESP] 17 June 2016 (has links)
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Previous issue date: 2016-06-17 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo do presente estudo foi avaliar o desempenho na produção embrionária in vivo e in vitro de doadoras da raça Holandesa não lactantes, verificar a ocorrência de polimorfismos no gene JY-1 e sua associação com a produção in vivo e in vitro de embriões. Primeiramente, foi verificada a similaridade na produção de embrião da mesma doadora entre as biotécnicas (produção in vivo e in vitro), sendo utilizadas 44 vacas e comparados os desempenhos nas produções de embrião. Na produção in vivo de embriões não foram observados efeitos de ano (P=0,13), estação dentro de ano (P=0,46) e touro dentro de estação e ano (P=0,20). Na produção in vitro, também não foram observados efeitos de ano (P=0,64) e estação dentro de ano (P=0,72), entretanto, o efeito do touro dentro da estação e ano foi significativo (P<0,01). Não há correlação entre as produções in vivo e in vitro dentro de doadora (r=- 0,04; P=0,56). Nenhuma probabilidade de semelhança entre as biotécnicas de produção de embriões, ou seja, se a mesma doadora tem o mesmo desempenho nas duas técnicas (acima ou abaixo da média), foi encontrada (P=0,12). Para verificar a ocorrência de polimorfismos no gene JY-1 e sua associação com a produção embrionária, dados retrospectivos de produções in vivo e in vitro de embriões foram obtidos de 144 vacas não lactantes da raça Holandesa. Para a identificação dos polimorfismos do gene JY-1, as regiões do éxon 2 e íntron 2 foram amplificadas e sequenciadas pelo método de PCR-sequenciamento. Foram detectados quatro SNPs [dois no éxon 2 (rs381676360; rs384600927) e dois no íntron 2 (rs378994837; rs211595914)]. O SNP rs381676360 provocou uma substituição não sinônima de aminoácido (leucina/isoleucina) e o rs384600927, uma substituição sinônima do aminoácido valina. Em relação ao equilíbrio de Hardy-Weinberg, uma das quatro frequências genotípicas não se encontrava em equilíbrio (rs211595914; P<0,01). Considerando o teste de desequilíbrio de ligação (DL), maiores valores de r2 (>0,33) foram observados entre os SNPs rs381676360, rs384600927 e rs378994837 (r2=0,767-0,973) e um SNP (rs211595914) apresentou baixos valores de r2 (r2=0,016-0,025). A associação dos SNPs com as características [número de embriões transferíveis produzidos in vivo (NET); taxa de embriões transferíveis in vivo; (%ET); número de embriões produzidos in vitro (NEV); taxa de clivagem (%CLIV) e taxa de embriões in vitro (%EV)] foi verificada. Nenhum dos SNPs isoladamente foi associado às características estudadas. Porém, quando todos os SNPs foram considerados em conjunto quanto à associação às características, valores significativos foram encontrados para o NET (P<0,01), NEV (P<0,01) e %EV (P<0,01). Desta forma, é possível concluir que o desempenho de produção de doadores de embriões depende da biotécnica utilizada. Ainda, que o gene JY-1 possui polimorfismos do tipo SNP em vacas não lactantes da raça Holandesa e que estes estão associados à produção embrionária. / The aim of this study was to evaluate the performance in in vivo and in vitro embryo production in non-lactating Holstein donors, verify the occurrence of JY-1 gene polymorphisms and their association with the in vivo and in vitro embryo production. First, the similarity in embryo production from the same donor between biotechnologies (in vivo and in vitro production) was verified, being used 44 cows and the embryo production performance was compared. In in vivo embryo production no effects of year (P=0.13), season within year (P=0.46) and sire within the season and year (P=0.20) were found. Regarding in vitro embryo production, no effects of year (P=0.64) and season within year (P=0.72) were found, however, the effect of sire within season and year was significant (P<0.01). There was no correlation concerning embryo production between techniques within donors (r=- 0.04, P=0.56). No probability of similarity between the embryo production techniques, i.e., if the same donor has the same performance in two techniques (above or below of the average), was found (P=0.12). To check the occurrence of JY-1 gene polymorphisms and their association with embryo production, retrospective data from in vivo and in vitro embryo production were obtained from 144 non-lactating Holstein cows. For the identification off JY-1 gene polymorphisms, the region of exon 2 and intron 2 was amplified and sequenced by PCR-sequencing method. Four SNPs were found [two in exon 2 (rs381676360; rs384600927) and two in intron 2 (rs378994837; rs211595914)]. SNP rs381676360 caused a non-synonymous amino acid substitution (leucine/isoleucine) and rs384600927 a synonymous substitution of the valine amino acid. Regarding the Hardy-Weinberg equilibrium, one of the four genotypic frequencies was not in equilibrium (rs211595914; P<0.01). For linkage disequilibrium test (LD) higher r2 values (>0.33) were observed between the SNPs rs381676360, rs384600927 and rs378994837 (r2=0.767 to 0.973) and one SNP (rs211595914) showed lower r2 values (r2=0.016 to 0.025). The association of SNPs with the characteristics [number of in vivo transferable embryos (NET); in vivo transferable embryo rate; (%ET); number of in vitro embryos (NEV); cleavage rate (% CLIV) and in vitro embryo rate (%EV)] was observed. None of the SNPs alone was associated with traits. However, when all SNPs were considered together for the association, significant values were found for NET (P<0.01), NEV (P<0.01) and %EV (P<0.01). Thus, it is possible to conclude that the donor embryo production performance depends on the implemented technique. Still, the JY-1 gene has SNP polymorphisms and they are associated with embryo production in non-lactating Holstein cows. / CNPq: 447172/2014-0 / FAPESP: 2014/13162-1
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ASPIRAÇÃO DE CORPO ESTRANHO EM MENORES DE 15 ANOS: UMA DÉCADA DE EXPERIÊNCIA / ASPIRATION OF STRANGE BODY IN MINORS OF 15 YEARS: ONE DECADE OF EXPERIENCESousa, Silvia Teresa Evangelista Vidotto de 24 September 2007 (has links)
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Previous issue date: 2007-09-24 / Airway aspiration of foreign body (FB) is a universal problem and an important cause
of morbidity and mortality especially for children and the elderly. FB aspiration was
evaluated in 72 children and teenagers varying from 7 months to 15 years of age who
underwent rigid bronchoscopy at the CMUH (Children Maternal University Hospital),
in São Luís-MA/ Brazil, for FB aspiration in the period from 1995 to 2005. For data
collecting, an index card was filled out for each patient. Epi-info and Bio-estata
programs were used for processing and statistical analysis. A major prevalence of FB
aspiration from 1998 through 2001 was observed. Most patients were from the
countryside (55.6%). The predominant age was the firsts three years of life (81.9%).
The prevalence was greater among the male sex (63.9%). In 83.3% of the cases the
initial diagnosis was FB aspiration. The elapsed time between the aspiration and the
bronchoscopy was greater than 72h (52.8 %). The most frequent site was the right lung
(38.9 %). The most common types of FB found were of organic nature (83.3 %). The
most prevailing radiological finding was hypotransparence (56.9%). Bronchitis was the
most frequently reported complication related to FB aspiration (45.9%), and glottis
edema was a major complication upon bronchoscopy (47.6%), with no deaths reported
in the studied group. It is concluded that bronchoscopy is a safe, highly sensible and
efficient procedure for the diagnosis and treatment of FB aspiration, and that a late
diagnosis suggests a need for better qualification of the health professionals. / A aspiração de corpo estranho (ACE) para via aérea é um problema universal e uma
importante causa de morbidade e mortalidade, especialmente em crianças e idosos.
Avaliou-se a aspiração de corpo estranho em 72 crianças na faixa etária de 7 meses a 15
anos submetidas à endoscopia respiratória no Hospital Universitário Materno Infantil
(HUMI) por ACE, no período de 1995 a 2005, São Luís - Maranhão. Para cada paciente
estudado foi preenchida uma ficha de coleta de dados. Utilizou-se os programas Epi-
Info e BioEstata para o processamento e análise estatística. Observou-se uma maior
prevalência de ACE nos anos de 1998 a 2001. A maior procedência foi das cidades do
interior (55,6%). A idade predominante foi nos três primeiros anos de vida (81,9%). A
prevalência foi maior no sexo masculino (63,9%). Em 83,3% dos casos, o diagnóstico
inicial foi de ACE. O tempo decorrido entre a aspiração e o exame endoscópico foi
maior que 72h (52,8%). A localização mais freqüente foi o pulmão direito (38,9%). O
tipo de corpo estranho (CE) mais encontrado foi o orgânico (83,3%). O achado
radiológico mais prevalente foi a hipotransparência (56,9%). A complicação mais
freqüente relacionada ao CE foi a bronquite (45,9%) A complicação relacionada ao
exame endoscópico mais freqüente foi o edema de glote (47,6%), não havendo óbitos.
Concluiu-se que a endoscopia respiratória mostrou-se um procedimento seguro, eficaz e
de alta sensibilidade no diagnóstico e tratamento do ACE e que a demora no seu
diagnóstico sugere a necessidade de melhor qualificação dos profissionais de saúde.
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Avaliação do TSH sérico como fator preditivo de malignidade em nódulos tireoidianos de pacientes submetidos à punção aspirativa por agulha finaCristo, Ana Patrícia de January 2013 (has links)
Nódulos de tireoide são achados clínicos comuns e, atualmente, o método diagnóstico de escolha para diferenciar lesões benignas de lesões malignas é a análise citopatológica dos nódulos através de punção aspirativa por agulha fina (PAAF). Estudos prévios já indicaram que os níveis séricos de TSH podem estar associados ao risco de malignidade nodular. O objetivo deste estudo foi avaliar se o TSH sérico é um preditor de malignidade em nódulos de tireoide em pacientes submetidos à PAAF. A amostra contemplou 100 indivíduos puncionados consecutivamente no Centro de Pronto Diagnóstico Ambulatorial, CPDA, HCPA e que apresentavam níveis de TSH dentro da normalidade. Todos os pacientes foram submetidos à PAAF da tireoide com controle ultrassonográfico e tiveram, posteriormente, a análise citopatológica da PAAF e a avaliação histopatológica do bloco celular. A análise estatística baseou-se em dados de frequências e testes não-paramétricos foram utilizados para correlacionar as variáveis. A população de estudo foi composta por 100 pacientes, sendo 89 mulheres e 11 homens. A média de idade foi de 54,1 ± 14,2 anos e o tamanho médio dos nódulos foi de 2.53 ± 1.36 centímetros. Vinte e seis % destes pacientes apresentavam algum tipo de doença tireoidiana prévia. A média do nível de TSH sérico entre os 100 indivíduos foi de 1.81 ± 1.08 uUI/mL. De acordo com o diagnóstico citopatológico da PAAF complementado pelos achados do bloco celular foram classificados como malignos 8% dos nódulos, 70% benignos, 11% suspeitos/ indeterminados, 8% insuficientes e 3% lesões foliculares. A média de TSH para os grupos maligno, benigno, suspeito/indeterminado, insuficiente e lesão folicular foi de, respectivamente, 2.48, 1.59, 2.21, 2.35 e 2.20 uUI/ml (p>0.05). Não houve diferença estatística significante entre os grupos diagnósticos avaliados, apesar de haver uma variação entre os níveis de TSH entre os grupos refletindo, provavelmente, o pequeno tamanho da amostra. / Thyroid nodules are common and currently the first choice of investigation in distinguishing benign from malignant disease is the cytological analysis of fine needle aspiration biopsy (FNAB). Previous studies have indicated that serum TSH levels might be associated with the likelihood of malignancy. The aim of this study was to evaluate whether serum TSH is a predictor of malignancy of thyroid nodules in patients undergoing FNAB. One hundred consecutive patients, who underwent FNAB as part of clinical investigation of thyroid nodule in a multidisciplinary setting tertiary hospital, underwent ultrasonography followed by FNAB, cytology and cell block analysis. Independent-Samples Kruskal-Wallis test was used to compare the groups. The study population comprised of 89 female and 11 male patients. The mean age was 54.1 ± 14.2 years. 26% had previous thyroid disease. Mean TSH levels was 1.81 ± 1.08 uUI/mL and the mean nodule size was 2.53 ± 1.36cm. Final cytology/cell block diagnosis classified 8% as malignant, 70% as benign, 11% suspicious/indeterminate, 8% insufficient and 3% follicular lesion. The mean TSH values for malignant, benign, suspect, insufficient and follicular lesion group were as follows: 2.48, 1.59, 2.21, 2.35 and 2.20 uUI/ml, respectively. No statistical significance was detected between TSH levels and final cytology/cell block diagnosis, possibly reflecting the small sample size (P>0.05). We observed a variation between TSH levels among the groups covered in this study, but there was no statistically significant difference among them.
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Parallelizing Tabu Search Based Optimization Algorithm on GPUsMalleypally, Vinaya 14 March 2018 (has links)
There are many combinatorial optimization problems such as traveling salesman problem, quadratic-assignment problem, flow shop scheduling, that are computationally intractable. Tabu search based simulated annealing is a stochastic search algorithm that is widely used to solve combinatorial optimization problems. Due to excessive run time, there is a strong demand for a parallel version that can be applied to any problem with minimal modifications. Existing advanced and/or parallel versions of tabu search algorithms are specific to the problem at hand. This leads to a drawback of optimization only for that particular problem. In this work, we propose a parallel version of tabu search based SA on the Graphics Processing Unit (GPU) platform. We propose two variants of the algorithm based on where the tabu list is stored (global vs. local). In the first version, the list is stored in the global shared memory such that all threads can access this list. Multiple random walks in solution space are carried out. Each walk avoids the moves made in rest of the walks due to their access to global tabu list at the expense of more time. In the second version, the list is stored at the block level and is shared by only the block threads. Groups of random walks are performed in parallel and a walk in a group avoids the moves made by the rest of the walks within that group due to their access to shared local tabu list. This version is better than the first version in terms of execution time. On the other hand, the first version finds the global optima more often. We present experimental results for six difficult optimization functions with known global optima. Compared to the CPU implementation with similar workload, the proposed GPU versions are faster by approximately three orders of magnitude and often find the global optima.
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Dynamiques d'aspirations d'interfaces complexesDurth, Mélanie 15 March 2012 (has links) (PDF)
Intéressés par la caractérisation d'objets biologiques de faibles volumes (bile, agrégats cellulaires), nous élaborons un rhéomètre par aspiration capillaire. Les propriétés physiques du fluide, aspiré à pression contrôlée, sont mesurées 'a partir de la déformation et de la dynamique du fluide dans le capillaire. Nous étalonnons d'abord le rhéomètre avec des fluides Newtoniens. La pression critique liée à la déformation initiale de l'interface dans le capillaire, donne une mesure de sa tension de surface. Le profil d'avancée du fluide, en fonction de la pression d'aspiration, donne une mesure de sa viscosité. En aspirant à pression constante ou à pression variable (linéaire en temps), nous étendons le domaine aux viscosités allant de 10−3 (bile) à 105 Pa.s (agrégats cellulaire), une gamme adéquate pour l'étude d'objets biologiques. Nous utilisons ensuite ce dispositif pour caractériser certains fluides complexes. Nous choisissons le carbopol dont la contrainte évolue selon la loi d'Herschel-Bulkley. La pression critique d'aspiration donne une mesure de la tension de surface et de la contrainte seuil du carbopol. Aspiré à pression linéaire en temps, le carbopol entre à vitesse constante et nous en déduisons ses paramètres rhéologiques. Enfin, nous aspirons des agrégats cellulaires aux propriétés viscoélastiques. L'aspiration à pression constante donne une mesure de la viscosité de l'agrégat aux temps longs, tandis que l'aspiration à pression variable, donne une valeur de l'élasticité de l'agrégat.
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Deep brain stimulation : effects on swallowing function in Parkinson's diseaseKulneff, Linda, Sundstedt, Stina, Olofsson, Katarina, van Doorn, Jan, Linder, Jan, Nordh, Erik, Blomstedt, Patric January 2013 (has links)
Objective: In patients with Parkinson’s disease (PD), deep brainstimulation of the subthalamic nucleus (STN DBS) is well recognizedin improving limb function, but the outcome on swallowing functionhas rarely been studied. The aim of this work was to evaluate theeffect of STN DBS on pharyngeal swallowing function in patientswith PD using self-estimation and fiberoptic endoscopic evaluation ofswallowing. Methods: Eleven patients (aged 41–72, median 61 years)were evaluated preoperatively and at 6 and 12 months after STN DBSsurgery. All patients were evaluated with self-estimation on a visualanalogue scale, and eight of them with a fiberoptic endoscopicexamination with a predefined swallowing protocol includingRosenbek’s Penetration-Aspiration Scale, Secretion Severity Scale,preswallow spillage, pharyngeal residue, and pharyngeal clearance. Results: The self-assessments of swallowing function revealed asubjective improvement with STN DBS stimulation, whereas the datafrom the swallowing protocol did not show any significant effect ofthe STN DBS treatment itself. The prevalence of aspiration was notaffected by the surgery. Conclusions: The results show thatswallowing function was not negatively affected by STN DBS and therisk of aspiration did not increase. Self-estimation of swallowingfunction showed a subjective improvement due to stimulation / Speech, voice and swallowing outcomes after deep brain stimulation (DBS)
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