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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.
281

Efeito da angiotensina-(1-7) no fluxo reabsortivo de bicarbonato (JHCO3-) e na concentração citosólica de cálcio ([Ca2+]i): estudo por microperfusão tubular proximal, in vivo. / Effect of angiotensin-(1-7) on the net reabsortive flow of bicarbonate and on calcium cytosolic concentration: study by in vivo proximal tubular microperfusion.

Branco, Regiane Cardoso Castelo 23 April 2012 (has links)
O estudo avaliou os efeitos agudos da Ang-(1-7) na reabsorção de bicarbonato (JHCO3-) no túbulo proximal cortical de rato, in vivo, medindo o pH intratubular pelo microeletródio sensível a H+. O JHCO3- controle é 2,84 ± 0,08 nmol. cm-2. s-1 (49), a Ang-(1-7; 10-12 ou 10-9 M) o reduz (35 ou 61 %) e a Ang-(1-7; 10-6 M) o eleva (56 %). A inibição do receptor Mas (por A779) eleva o JHCO3- (30 %), abole o efeito inibidor da Ang-(1-7), mas não afeta seu efeito estimulador. A inibição do NHE3 (por S3226) diminui o JHCO3- (45 %), não altera o efeito inibidor da Ang-(1-7), mas transforma seu efeito estimulador em inibidor. A concentração de cálcio citosólico ([Ca2+]i), medida pelo FURA-2-AM, controle é 100 ± 2,47 nM (35) e a Ang-(1-7; 10-12, 10-9 ou 10-6 M) a aumenta (152, 103 ou 53 %) transientemente (3 min). A inibição do receptor Mas aumenta a [Ca2+]i (26 %), mais inibe o efeito estimulador de todas as doses de Ang-(1-7). Os resultados indicam que o efeito bifásico dose-dependente da Ang-(1-7) sobre o JHCO3- no túbulo proximal é via receptor Mas e isoforma NHE3 e sugerem estimulação desse trocador por moderado aumento da [Ca2+]i na presença de Ang-(1-7; 10-6 M) e sua inibição por pronunciado aumento da [Ca2+]i na vigência de Ang-(1-7; 10-12 ou 10-9 M). / The action of Ang-(1-7) on bicarbonate reabsorption (JHCO3-) was evaluated in vivo middle proximal tubule of rat kidney, using H ion-sensitive microelectrodes. The control JHCO3- is 2,84 ± 0.08 nmol. cm-2. s-1 (49), Ang-(1-7; 10-12 or 10-9 M) decreases it (35 and 61 %) but Ang-(1-7; 10-6 M) increased it (56 %). A779 (an Ang-(1-7) receptor Mas antagonist) increases the JHCO3- (30 %), prevents the inhibitory effect of Ang-(1-7) and does not affect the stimulatory effect of Ang-(1-7). S3226 (10-6 M; an inhibitor of NHE3) decreases the JHCO3- (45 %), does not affect the inhibitory effect of Ang-(1-7) and changes its stimulatory effect on an inhibitory effect. The control cytosolic free calcium ([Ca2+]i), monitored by FURA-2-AM, is 100 ± 2,47 nM (35) and Ang-(1-7; 10-12, 10-9 or 10-6 M) causes a transient (3 min) increase of it (152, 103 or 53 %). A779 increases the [Ca2+]i (26 %) but impaired the stimulatory effect of Ang-(1-7). Our results indicate the biphasic dose-dependent effect of Ang-(1-7) on JHCO3- in proximal tubule is mediated via Mas receptor and NHE3 and are compatible with stimulation of this exchanger by a moderate increase in [Ca2+]i in the presence of Ang-(1-7, 10-6 M), and its inhibition by large increase in [Ca2+]i with Ang-(1-7, 10-12 or 10-9 M).
282

What Vocabulary do Swedish Nursery Children Master Orally in English as a Second Language? : A Study on Swedish nursery children’s oral vocabulary knowledge in English

Engström, Linnéa January 2019 (has links)
This essay examines Swedish nursery children’s oral vocabulary knowledge in English. The aim is to investigate what they know and find the source to their knowledge. This essay will focus on the receptive and productive knowledge the children know based on the categories tested, how much children learn in their Zone of Proximal Development, how much they learn from context and how much does media and electronic devices influence their learning. The data of this essay were collected from interviews of 25 children and from questionnaires answered by their parents. The results of the study indicate that the children have more receptive knowledge of the English words tested. It also suggests that the productive knowledge they have is connected with the words that sound similar in Swedish and that children learn English from their surroundings such as siblings and parents, and from games on iPads and video clips from YouTube.
283

Avaliação da liberação de AGEs (Advanced Glycation End Products) e características sensorias em carne de frango e bovina em diferentes métodos de cocção

Teles, Luana Duarte 30 July 2014 (has links)
Submitted by Fabricia Fialho Reginato (fabriciar) on 2015-08-24T23:44:58Z No. of bitstreams: 1 LuanaTeles.pdf: 317432 bytes, checksum: 2fbd7369c410c0b3afac913a4136f4f0 (MD5) / Made available in DSpace on 2015-08-24T23:44:58Z (GMT). No. of bitstreams: 1 LuanaTeles.pdf: 317432 bytes, checksum: 2fbd7369c410c0b3afac913a4136f4f0 (MD5) Previous issue date: 2014-07-30 / Nenhuma / As práticas alimentares têm sido objeto de estudo das Ciências da Saúde, principalmente, evidenciando a relação entre a dieta e algumas doenças crônicas. Dessa forma, é importante a identificação de formas alternativas de preparo e cocção, as quais devem manter a qualidade nutricional e as características sensoriais dos alimentos. Assim, o objetivo deste trabalho foi avaliar o efeito de diferentes métodos de cocção que utilizam alta temperatura, maior que 100 oC (assar e grelhar) e um método que utiliza baixa temperatura (menor que 100 oC), o método sous vide, sobre a liberação de produtos finais de glicação avançada das proteínas (Advanced Glycated End-Products – AGEs) durante o processo de cozimento de peito de frango e filé de gado. Além disso, foi avaliada a composição proximal (proteína, lipídios, cinzas e carboidratos e minerais), bem como, sua aceitação sensorial. A quantidade de AGEs formados e de proteína solúvel foi analisada nos cortes crus, assados em 9 e 21 minutos, grelhados em 3 e 15 minutos e sous-vide em 30 e 42 minutos, através da técnica de ELISA, utilizando um anticorpo monoclonal anti-AGE e o método de Bradford, respectivamente. A composição proximal e de minerais foi determinada no filé e peito crus, grelhados (em 3 e 9 minutos) e sous-vide (30 e 36 minutos). A análise sensorial de aceitação avaliou os atributos aparência, textura, sabor e qualidade global nos cortes assados (15 min), grelhados (9 min), sous-vide (36 min) e sous-vide (36 min) maçaricado. O índice de aceitabilidade sensorial também foi calculado. O corte de peito de frango apresentou aumento da quantidade de AGEs quando submetido aos diferentes métodos de cocção avaliados com o aumento do tempo de cozimento. O método assar promoveu a maior formação de AGEs no peito de frango ao longo do tempo. Esses comportamentos não foram encontrados no filé bovino e na comparação entre ambos os cortes crus e cozidos. O teor de proteína solúvel no filé de gado e no peito de frango crus foi maior do que nos cozidos e sua quantidade diminuiu com o passar do tempo de cocção no filé assado e no peito grelhado. Observou-se a diminuição do teor de umidade e o aumento do nível dos macronutrientes e minerais quando os cortes foram submetidos à cocção e com o passar do tempo de cozimento. Na análise sensorial, o filé bovino e o peito de frango grelhados apresentaram a maior aceitação e índice de aceitabilidade, seguido pelo sous-vide maçaricado, ao passo que o sous-vide obteve a menor aceitação de modo geral. / Feeding practices have been studied by Health Sciences, mainly showing the relationship between diet and some chronic diseases. Thus, it is important to identify alternative ways of preparing and cooking, which shall maintain food nutritional quality and sensory characteristics. The objective of this study was to evaluate the effect of different cooking methods that use high temperature greater than 100 oC (bake and broil) and a method that uses low-temperature (less than 100 oC), sous vide, on the release Advanced Glycation End Products (AGEs) in the chicken breast and filet mignon. In addition, the proximate composition (protein, lipid, ash and carbohydrate and minerals) were evaluated as well as their sensory acceptability. The amount of AGEs formed and soluble protein was analyzed in raw cuts, baked in 9 and 21 minutes, grilled in 3 and 15 minutes and sous-vide in 30 and 42 minutes by ELISA using the anti-AGE monoclonal antibody specific and Bradford method, respectively. The proximate and mineral composition was determined in raw breast and fillet, grilled (3 and 9 minutes) and sous-vide (30 and 36 minutes). The sensory analysis assessed appearance, texture, flavor and overall quality attributes in baked (15 min), grilled (9 min), sous-vide (36 min) and sous-vide (36 min) burned cuts. The sensory acceptability index was also calculated. Chicken breast showed increased amount of AGEs when subjected to different cooking methods evaluated with increased cooking time. The baking method promoted the AGEs highest formation in breast over time. These behaviors were not found in filet and in the comparison between raw and cooked cuts. The raw filet and breast soluble protein content was higher than in boiled and decreased with the time cooking in roast filet and grilled breast. Decline in moisture and increasing in macronutrients and minerals levels was observed when cuts were cooking and over cooking time. In sensory analysis, grilled filet and breast had the highest acceptance and acceptability index, followed by sous-vide burned, while sous-vide got lower acceptance in general.
284

Avaliação da integridade do acrossoma, membrana citoplasmática, potencial mitocondrial, cromática e produção de embriões in vitro de sêmen bovino com altos índices de gota citoplasmática proximal /

Carreira, Janaina Torres. January 2008 (has links)
Orientadora: Marion Burkhardt de Koivisto / Banca: Gisele Zoccal Mingoti / Banca: Sony Dimas Bicudo / Resumo: O objetivo deste trabalho foi avaliar os efeitos da gota citoplasmática proximal (GCP) no sêmen de bovinos quanto à integridade do DNA, das membranas citoplasmática, acrossomal, no potencial mitocondrial e verificar a taxa de produção de embriões in vitro. Três amostras descongeladas de cinco (Controle: espermiograma normal), e oito touros Bos indicus (Gota: GCP ≥15%) foram avaliadas. Foram realizados os seguintes testes: motilidade e vigor pós-descongelação, concentração, morfologia espermática, teste de termo-resistência lento (TTL), integridade da membrana acrossomal, plasmática e potencial mitocondrial utilizando sondas fluorescentes (PI, FITC-PSA e JC-1) e integridade da cromatina pelo método de coloração com laranja de acridina. Dois touros com índices elevados de GCP e três animais controle foram selecionados para fertilização in vitro (FIV). As análises estatísticas foram efetuadas empregando-se o programa Statistical Analysis System. O nível de significância foi de 5%. Os resultados obtidos demonstraram que altos índices de GCP não afetaram a motilidade e o vigor, antes e após o TTL, assim como não interferiram na porcentagem de acrossomas intactos. Os resultados destas avaliações mostraram que a alta incidência de GCP afetou a integridade da membrana acrossomal e plasmática bem como a presença de potencial mitocondrial. No entanto, a alta incidência de GCP não promoveu aumento na porcentagem de injúrias à cromatina após descongelação, mas os resultados sugerem que podem ser mais sensíveis à desnaturação quando incubados por três horas. No experimento II, os índices de produção de embriões in vitro podem ter sido afetados pela interação da alteração morfológica e o efeito individual do touro. / Abstract: The objective of this study was to evaluate the effects of the proximal cytoplasmic droplets (PCD) in bovine semen, on the integrity of DNA, cytoplasmic membrane, acrossome, mitochondrial function and the rate of in vitro embryo production. Three batches of five (control group G1: normal sperm parameters) and eight Bos indicus bulls (G2: PCD ≥15%) were analysed. The following tests were carried out: post thaw motility and, vigor, concentration, sperm morphology, slow thermo-resistance (TRT), membrane integrity, acrossome status, mitochondrial function through fluorescent probes (FITC-PSA, PI and JC-1) and integrity of chromatin was accessed by acridine orange stain. Two bulls with high rates of PCD and three animals (control group) were selected for in vitro fertilization (IVF). Statistical analyses were performed using the Statistical Analysis System. The significance level was 5%. The results showed that high rates of PCD did not affect motility and vigor, before and after the TRT, and did not affect the percentage of intact acrossome. The results showed that the high incidence of PCD affected membrane integrity, acrossome status and mitochondrial function when compared to the G1 group due. However, the high incidence of PCD did not affect the percentage of chromatin injury after thawing, but results suggest that spermatozoa may be more susceptible to damage when incubated for three hours. In experiment II the embryo production rate may have been affected by the interaction of the morphology traits and the bull effect. / Mestre
285

Espectroscopia de reflectância do visível ao infravermelho médio aplicada aos estudos qualitativos e quantitativos de solos / Reflectance spectroscopy from visible to mid-infrared applied for qualitative and quantitative studies of sois

Fabricio da Silva Terra 09 February 2012 (has links)
Com a intensificação e expansão da produção agrícola brasileira, seguidas da crescente preocupação ambiental, surge a necessidade da adoção de novas tecnologias para o monitoramento e avaliação em larga escala dos recursos naturais, em especial o solo. Nesse sentido a espectroscopia de reflectância, aliada as bibliotecas espectrais, atende estas expectativas por ser uma técnica eficiente, rápida, barata e não poluente, pois não usa reagentes e nem gera resíduos, porém sua aplicação nos solos tropicais brasileiros ainda é incipientes e carece de mais estudos. Sendo assim, o objetivo principal do trabalho foi comparar as informações espectrais obtidas por espectroscopia de reflectância nas faixas do visível, infravermelho próximo e, principalmente, no infravermelho médio com análises convencionais de solo a fim entender as relações existentes entre o comportamento espectral e os atributos físicos, químicos e mineralógicos dos solos estudados, ainda quantificar e caracterizar a variabilidade desses atributos e dos solos com base no comportamento espectral. Para tanto, foram utilizadas 1288 amostras de solo correspondentes a diferentes horizontes de 458 perfis da região central brasileira (GO, MS, MG e SP), sobre as quais foram procedidas análise granulométrica e química, para fins de levantamento de solos, e mineralógica. Os espectros VisNIR foram adquiridos com o sensor FieldSpec Pro, enquanto que espectros Mid-IR com o sensor Nicolet 6700 Fourier Transform Infrared (FT-IR) e, após isso, os dados foram transformados com os seguintes préprocessamentos: remoção do espectro contínuo, absorbância e correção da linha base. As diferentes faixas espectrais também foram combinadas pela outer product analysis. A distribuição dos dados espectrais e a influência de cada atributo nos comportamentos espectrais dos solos foram avaliadas através de análises estatísticas multivariadas, tais como correlação multivariada, análise por componentes principais, seguidas das análises de agrupamento kmédias, para a avaliação entre amostras, e distância taxonômica, para avaliação entre perfis. A predição dos atributos dos solos com base nos dados espectrais foi determinada pelos algoritmos de regressão multivariada: mínimos quadrados parciais (PLSR), árvores de regressão ampliadas (BT) e máquina de vetor suporte (SVM); sendo que a qualidade das predições foi definida pelos R2, RMSE, RPD e RPIQ. O comportamento espectral das principais classes de solos tropicais brasileiros, em ambas as faixas espectrais, foi apresentado juntamente com as principais feições de absorção diagnosticadas (minerais 2:1, caulinita, óxidos de Fe e Al), assim como a contribuição de cada atributo do solo na variação dos espectros. Foi possível estabelecer a formação de grupos de solo com base no grau de intemperismo das amostras, enquanto que os perfis das principais classes de solos puderam ser discriminados com base na variação do comportamento espectral em profundidade. Grande parte dos atributos estudados pode ser quantificada nas duas faixas espectrais pelo menos com um nível de qualidade razoável (RPD > 1,40), sendo que o principal algoritmo de predição foi o SVM com os espectros em valores de absorbância. A espectroscopia de reflectância, principalmente na faixa Mid-IR, apresenta-se como uma tecnologia eficaz de alta potencialidade e aplicabilidade nas análises qualitativa e quantitativas dos solos, principalmente para fins de levantamento e mapeamento. / Considering the intensification and expansion of Brazilian agricultural production followed by the growing environmental concern, there is the necessity of adopting new technologies to monitor on a large scale the natural resources, in particular, the soil. In this sense, reflectance spectroscopy, integrated with spectral libraries, meets that expectation as an alternative for proximal soil sensing because its more efficient than other techniques being cheaper and faster than conventional analyses, besides, it doesnt produce waste. However, its application on Brazilian tropical soils is still incipient and needs more studies. The main aim of this research was to compare spectral information acquired by reflectance spectroscopy in the visible, near infrared and, mainly, in the mid infrared ranges with conventional soil analyses in order to understand the relationships among spectral behavior and physical, chemical, and mineralogical attributes of the studied soils, also, to quantify and characterize the variability of these attributes and soils based on their spectral behavior. For that, a dataset with 1288 soil samples referring to different horizons from 458 soil profiles from the central region of Brazil (States of Goiás, Mato Grosso do Sul, Minas Gerais e São Paulo) was used, and convetional analyses (granulometric, chemical and mineralogical) for soil survey were applied over them. VisNIR reflectance data were acquired by the FiledSpec Pro sensor whereas Mid-IR spectral data were acquired by the Nicolet 6700 (FT-IR) sensor and, after that, both data were transformed by the following pre-processing: continuum removal, absorbance and baseline correction. The different spectral ranges were also combined by outer product analysis. The data distribution and the influence of each attribute on soil spectral behavior were evaluated by multivariate statistical analyses, such as, multivariate correlations, principal component analysis followed by k-means clustering, for assessment among soil samples, and by taxonomic distance, for assessment among soil profiles. Predictions of soil attributes based on spectral data were modeled by following multivariate regression algorithms: partial least square regression (PLSR), boosted regression trees (BT) and support vector machine (SVM) and quality of modeling were evaluated by R2, RMSE, RPD and RPIQ. Spectral behavior of the main soil classes, in both ranges, were showed along with the absorption features of the major tropical minerals (2:1 minerals, kaolinite, Fe and Al oxides), as well as, the contribution of each soil attribute on spectra variations. Sample clustering based on different weathering levels of soils was possible regarding differences in absorbance intensities and features whereas profiles of the main soil classes could be discriminated based on variation of spectral behavior in depth. Much of the studied attributes could be predicted in both spectral range at least in a reasonable level of quality (RPD > 1,40), and SVM was considered the principal prediction algorithm as well as absorbance transformation as the major pre-processing. Reflectance spectroscopy, especially in the Mid-IR range, shows up as a high potential technique for qualitative and quantitative analysis of Brazilian soils, in particular for soil survey or mapping.
286

Teachers' Perception of Common Core State Standards on Students with Learning Disabilities

ShaBazz, Sarah 01 January 2019 (has links)
The Common Core State Standards were written and implemented to prepare all students for college or career readiness including students with disabilities. Students with learning disabilities often have significant difficulties and face challenges when the instruction is framed within The Common Core State Standards. The purpose of this qualitative study was to explore the perceptions of special educators on teaching students with learning disabilities using The Common Core State Standards. The two conceptual frameworks used in this study were the Universal Design for Learning and The Zone of Proximal Development. The research questions focused on teachers' perception regarding students with learning disabilities being instructed with Common Core instructions, how teachers perceive providing Common Core instructions to students with learning disabilities is preparing them for college and career readiness, and also, what teachers perceived to be the missing components for providing specialized instructions using Common Core to students with learning disabilities. In this qualitative case study participants were selected using recommendations of school district administrators. Data was collected using face-to-face interviews. Data collection also include observations and samples of students work. Additional data to establish trustworthiness of the study was obtained through observations and analysis of artifacts collected during the study. The intended outcome of the study was to bring about change in the instructional strategies adopted when using Common core State standards in teaching students with disabilities and that to ultimately pave a way for social change.
287

Interprétation et amélioration d'une procédure de démodulation itérative

Naja, Ziad 01 April 2011 (has links) (PDF)
La géométrie de l'information est la théorie mathématique qui applique les méthodes de la géométrie différentielle dans le domaine des statistiques et de la théorie de l'information. C'est une technique très prometteuse pour l'analyse et l'illustration des algorithmes itératifs utilisés en communications numériques. Cette thèse porte sur l'application de cette technique ainsi que d'autre technique d'optimisation bien connue, l'algorithme itératif du point proximal, sur les algorithmes itératifs en général. Nous avons ainsi trouvé des interprétations géométriques (basée sur la géométrie de l'information) et proximales (basée sur l'algorithme du point proximal)intéressantes dans le cas d'un algorithme itératif de calcul de la capacité des canaux discrets sans mémoire, l'algorithme de Blahut-Arimoto. L'idée étant d'étendre cette application sur une classe d'algorithmes itératifs plus complexes. Nous avons ainsi choisi d'analyser l'algorithme de décodage itératif des modulations codées à bits entrelacés afin de trouver quelques interprétations et essayer de proposer des liens existant avec le critère optimal de maximum de vraisemblance et d'autres algorithmes bien connus dans le but d'apporter certaines améliorations par rapport au cas classique de cet algorithme, en particulier l'étude de la convergence.Mots-clefs : Géométrie de l'information, algorithme du point proximal, algorithme de Blahut-Arimoto, décodage itératif, Modulations codées à bits entrelacés, maximum de vraisemblance.
288

Comportement asymptotique de systèmes dynamiques discrets et continus en Optimisation et EDP: algorithmes de minimisation proximale alternée et dynamique du deuxième ordre à dissipation évanescente

Frankel, Pierre 27 August 2001 (has links) (PDF)
La première partie de cette thèse (articles 1 et 2) est consacrée à l'étude du comportement asymptotique des solutions de dynamiques du second ordre avec dissipation evanescente. La deuxième partie de cette thése (articles 3 à 6) est consacrée à l'étude de plusieurs algorithmes de type proximal. Nous montrons que ces algorithmes convergent vers des solutions de certains problèmes de minimisation. Dans chaque cas, une application est donnée dans le cadre de la décomposition de domaine pour les EDP.
289

Comparing the performance of storage phosphor plate and insight film for the detection of proximal caries depth.

Crombie, Karima. January 2008 (has links)
<p><font face="Arial"> <p align="left">The aim of this study is to compare proximal caries depth on unenhanced storage phosphor plate images and conventional film images. The phosphor plate images were then copied by increasing and decreasing both contrast and brightness respectively. The enhanced phosphor plate images were compared with the unenhanced storage phosphor plate images and conventional film images for the detection of proximal caries diagnosis.</p> </font></p>
290

The perceptions of intermediate phase educators about the implementation of Stories for Thinking in one Western Cape Education Department region

Agulhas. Ronald January 2011 (has links)
The methodology by which to teach these outcomes was not clear. An intervention programme, Philosophy for Children (P4C) is used in some countries across the world to promote thinking. Research across the world has shown that this programme has the ability to enhance the cognitive abilities of learners exposed to it. Stories for Thinking (SFT) is an intervention programme based on the principles of Philosophy for Children and was introduced in some schools in an Education District of the Western Cape. This study investigates the perceptions of Intermediate Phase educators about the implementation of Stories for Thinking in this Education District. Educators were asked their strengths and challenges of the approach, their way of using it and the support they received. A qualitative research method was used and data were gathered to answer the research questions by means of questionnaires and interviews. Research findings indicate that educators perceived that Stories for Thinking was able to enhance the reading ability of the learners, it showed a significant improvement in their confidence levels, and a positive change in their general behaviour. Language was seen as a barrier to learning, but the evidence indicates that the community of inquiry can be used as a tool to overcome some of the barriers. It seems as if educators valued the support from the project leaders. It is concluded that this kind of intervention programme is worth introducing as long as all the role-players play their part and the setting is conducive.

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