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Fenômeno de transição espacial do escoamento óleo pesado-água no padrão estratificado; Phenomenon of spatial transition in stratified heavy oil-water flow pattern

Castro, Marcelo Souza de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/06/2013 PT
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O escoamento estratificado óleo-água é comum na indústria de petróleo, em particular em poços direcionais e oleodutos. Estudos recentes mostram que o fenômeno de transição de padrões de escoamento de fases separadas pode estar relacionado à estrutura ondulatória da interface do escoamento (problema de estabilidade hidrodinâmica). A transição do padrão estratificado ao padrão estratificado com mistura na interface foi estudada por diversos autores sendo que a física envolvida está clara, e o fenômeno ocorre pelo arrancamento de gotículas da crista da onda interfacial. Técnicas baseadas na análise temporal da estabilidade hidrodinâmica para a proposição de critérios de transição são comumente encontradas na literatura. Entretanto, para certas condições de escoamento, foi observado que o padrão de escoamento estratificado muda ao longo da tubulação. O escoamento adentra a tubulação como estratificado ondulado e alguns diâmetros após a entrada ocorre a transição para o padrão bolhas alongadas. Foi também observado que o ponto no espaço em que o fenômeno ocorre varia com a elevação ou decréscimo das velocidades superficiais das fases. Aparentemente, tal fenômeno ocorre devido a efeitos de tensão interfacial e ângulo de contato. O modelo de dois fluidos unidimensional...

Is the chiral phase transition induced by a metal-insulator transition?

García-García,Antonio M.; Osborn,James C.
Fonte: Sociedade Brasileira de Física Publicador: Sociedade Brasileira de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2007 EN
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We investigate the QCD Dirac operator with gauge configurations given by a liquid of instantons in the region of temperatures about the chiral phase transition. Both the quenched and unquenched cases are examined in detail. We present evidence of a localization transition in the low lying modes of the Dirac operator around the same temperature as the chiral phase transition. Thus both level statistics and eigenvectors of the QCD Dirac operator at the chiral phase transition have similar properties than those of a disordered conductor at the metal-insulator transition. This strongly suggests the phenomenon of Anderson localization (localization by destructive quantum interference) is the leading physical mechanism in the restoration of the chiral symmetry. Finally we argue that our findings are not in principle restricted to the ILM approximation and may also be found in lattice simulations.

Spectroscopie Raman de complexes de fer(II) et fer(III) à transition de spin

Rollet, Frédéric-Guillaume
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Les transitions de spin provoquent des changements de propriétés physiques des complexes de métaux du bloc d les subissant, notamment de leur structure et propriétés spectroscopiques. Ce mémoire porte sur la spectroscopie Raman de composés du fer(II) et du fer(III), pour lesquels on induit une transition de spin par variation de la température ou de la pression. Trois complexes de fer(II) de type FeN4(NCS)2 avec des comportements de transition de spin différents ont été étudiés : Fe(Phen)2(NCS)2 (Phen : 1,10-Phénanthroline), Fe(Btz)2(NCS)2 (Btz : 2,2’-bi-4,5-dihydrothiazine) et Fe(pyridine)4(NCS)2. Un décalage de l’ordre de 50 cm-1 est observable pour la fréquence d’étirement C-N du ligand thiocyanate des complexes FeN4(NCS)2, lors de la transition de spin induite par variation de la température ou de la pression. Il est possible d’utiliser cette variation de fréquence afin de tracer un profil de transition. Quatre complexes isomères de type FeL222(CN)2 (L222 : 2,13- diméthyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]-octadéca-1(18),2,12,14,16-pentaène) ont également été étudiés. Un taux de décalage de l’ordre d’environ 0,03 cm-1/K est observé pour plusieurs bandes du complexe FeL222(CN)2. La bande à 1415 cm-1 disparaît à plus haute température au profit d’une bande à 1400 cm-1. Pour le complexe de chiralité R...

La transition des soins du milieu pédiatrique au milieu hospitalier adulte chez des adolescents transplantés rénaux et chez des adolescents diabétiques : évaluation de l’identité et de l’autodétermination

Lugasi, Tziona
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
EN
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Résumé Le pourcentage d’enfants et d’adolescents vivant avec une condition chronique qui atteint l’âge adulte a augmenté de façon significative au cours des dernières décennies grâce, notamment, aux avancées en médecine, donnant lieu à la question de transition du milieu hospitalier pédiatrique au milieu hospitalier adulte. Cette transition est décrite par plusieurs chercheurs et cliniciens comme étant un processus complexe pouvant être associé à des difficultés importantes, tel qu’un manque d’adhérence au suivi médical. Malgré les nombreux écrits sur cette problématique, peu d’études longitudinales ancrées dans un contexte théorique ont été réalisées. Le but de cette thèse est d’identifier des facteurs susceptibles de faciliter l’expérience de transition de patients atteints de diabète et de patients greffés rénaux en utilisant une méthodologie longitudinale ainsi qu’en se basant sur un contexte théorique défini et pertinent à la transition de l’adolescence à la vie adulte ainsi qu’à la prise en charge médicale. La thèse est présentée sous forme de trois articles scientifiques. Le premier article examine le développement identitaire, une tâche centrale pendant la période de l’adolescence. Selon la théorie de l’identité d’Erikson (1963) et de Marcia (1966)...

Modèle d’accompagnement des patients et des membres de leur famille lors de la transition vers des soins de fin de vie à l’unité des soins intensifs

Gaudette, Martin
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Travail aux cycles supérieurs / Graduate student work
FR
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Malgré tous les efforts déployés sur les unités de soins intensifs (USI) pour maintenir en vie les patients admis, plusieurs statistiques rapportent un nombre important de décès chaque année sur ces unités. Comme il arrive que le décès ne soit pas soudain, les traitements de soutien pour la vie doivent donc se transformer en soins de fin de vie. Les pratiques et expertises n’étant pas les mêmes sur une unité de soins palliatifs que sur une USI, tout comme les besoins des patients et des membres de sa famille sont différents, c’est ainsi que, lorsque vient le temps d’envisager et d’offrir des soins de fin de vie sur une USI, il est nécessaire de procéder à des ajustements dans les pratiques de soins afin de bien accompagner ces personnes devant leur nouvelle réalité. L’objectif de ce travail sera donc de proposer un modèle d’accompagnement des patients et des membres de leur famille lors de la transition vers les soins de fin de vie sur les USI. Pour se faire, une recension des écrits, pratiquée à l’aide de la méthode intégrative de Whittmore et Knafl (2005), a permis d’identifier différentes théories, approches et modèles proposés par différents chercheurs et auteurs. Le cadre de référence choisi aux fins de ce travail sera la théorie de la transition de Meleis. Après un examen attentif des écrits...

A critical examination and evaluation of the place of science in the Irish transition year

Hayes, Sarah
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/doctoralThesis; all_ul_research; ul_published_reviewed; ul_theses_dissertations
ENG
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peer-reviewed; The transition year is a unique year in the Irish education system, which has undergone much change since it started in 1974/5, and is now a well established part of Irish schools, being offered by three-quarters of schools, and taken by over half of the pupils. The transition year is a syllabus-free year, governed by some broad guidelines, unlike the Irish school system as a whole, which is highly standardised and examined. As a small country within the European Union, Ireland is well placed as a base for many science-based industries and science and technology have become a major focus of government policy, and hence science education is becoming increasingly important in Ireland. Like other developed nations Ireland is experiencing low numbers taking the physical sciences, but has disproportionately high numbers taking the biological sciences. The unique nature of the transition year offers schools and teachers an unprecedented opportunity to offer a relevant, interesting and innovative science programme, free from examination and curricular constraints. The purpose of this study was to examine and evaluate the place of science in the transition year. The study consisted of three phases. Phase 1 involved developing a questionnaire to find out what teachers were teaching in their transition year science classroom...

A Decade of Fiscal Transition

Alam, Asad; Sundberg, Mark
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
EN_US
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Transition literature has emphasized stabilization and enterprise restructuring. Both cross-country analyses and country-specific studies have tended to focus on fiscal stabilization and its indicators, highlighting the importance of quantitative fiscal adjustment to stabilization outcomes. Less attention has been paid to the qualitative dimensions of fiscal adjustment in transition. The authors take stock of the extent to which fiscal adjustment has occurred during the first decade of transition in both qualitative and quantitative dimensions. They define quality as the extent to which: (1) pro-growth expenditure essential for creating future economic and social assets are maintained; (2) pro-poor expenditure, such as poverty-targeted transfers, necessary to ensure income for the poor and vulnerable are adequately provided; and (3) fiscal risks, impinging on both expenditure and revenue, are managed through transition. The authors conclude that while the quantitative magnitude of the fiscal adjustment was dramatic...

What have we learnt about the cultural, social and behavioural determinants of health? From Selected Readings to the first Health Transition Workshop

Caldwell, John C
Fonte: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University Publicador: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University
Tipo: Artigo de Revista Científica Formato: 52049 bytes; application/pdf
EN_AU
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The article explores the issue of whether the holding of an international workshop in Canberra in 1989, and the preparation of papers for it, increased our knowledge of the cultural, social and behavioural determinants of health and whether the publication of the proceedings placed new knowledge in the public domain. The approach adopted is to compare those proceedings with a collection of selected readings on the subject made shortly before as part of the same program and also with certain other publications. The conclusions reached are that, in addition to having stimulated interest in the field, the workshop and its proceedings furthered knowledge in at least five important areas: (1) the existence of mortality-prone households; (2) the impact of differing cultural situations of women in terms of individualism on their children’s survival; (3) the mechanisms whereby maternal education is translated into child survival; (4) the impact of culture and ethnicity on mortality; and (5) indirect indices of the impact of care. The workshop failed to contribute to substantial advances (or draw attention to the lack of advance) in the following areas: (1) the measurement of Third World morbidity or health; (2) adult health transition; (3) the impact of radicalism or egalitarianism in communities other than Kerala and Sri Lanka on mortality; (4) the impact of lifestyle diseases on Third World mortality; (5) the identification of economically optimum mixes of social change and the provision of health services in reducing mortality and improving health; and (6) the employment of health transition knowledge in the reduction of mortality and the improvement of health.; no

How do they cope?: the transition to an undergraduate, case-based learning medical program at the University of Adelaide.

Raw, Lynne
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2013
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The transition to university has been described as a “battle” for students as their ways of learning are challenged and threatened. Most students transitioning into Medicine at the University of Adelaide encounter the Case-based Learning (CBL) approach, used across the whole curriculum, for the first time. The transition experiences of students across various university programs have been investigated but not for students entering medical programs. A Transition Pedagogy model which integrates co-curricular and curricular components provides a framework for investigating the complexities of the environment experienced by transitioning students. The framework designates key strategies in four dedicated areas that extend across six curriculum principles. The purpose of this study was to investigate strategies used in these four areas by transitioning students, academics and administrative staff in the specific context of a CBL medical program. A mixed-methods research design was used. Students, academics and administrative staff completed questionnaires and participated in Focus Groups. Students completed the “First Year Experience Questionnaire” (FYEQ) for comparison with a general cohort of first year university students studying at nine Australian universities. Students’ distress levels were measured two weeks before examinations in Semesters One and Two. Students and tutors completed questionnaires to investigate the alignment of their perceptions about the Case-based Learning approach. Tutors completed the “Approaches to Teaching Inventory” to investigate the relationship between a student’s perceptions of the CBL approach and their tutor’s approach to teaching. Focus Groups explored questionnaire findings to generate a deeper understanding of the strategies employed by students...

Fertility transition in England and Wales: continuity and change

Friedlander, Dov; Okun, Barbara S
Fonte: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University Publicador: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University
Tipo: Artigo de Revista Científica Formato: 58930 bytes; application/pdf
EN_AU
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The focus of this paper is whether the transition from high to low fertility reveals continuity or discontinuity with the past. Our analyses of districts of England and Wales over time reveal an overall picture of continuity. Specifically, we show that (1) a substantial proportion of districts experienced pretransition variations in marital fertility that were so large that they are suggestive of deliberate fertility control; (2) the changes over time in the distributions of marital fertility levels and the relative importance of marital fertility levels to the determination of overall fertility levels were gradual and smooth; (3) the proportion of districts dominated by marital fertiliity variation, as opposed to nuptiality variation, increased gradually over time, and both marital fertility and nuptiality variations were present in all periods considered; and (4) there are important relationships between changes over time in marital fertility and socio-economic variables in periods both before and after the transition. The last conclusion is based on our estimated equations from the pooled cross-sectional, time-series data. Moreover, these estimated equations reveal relationships between changes in specific explanatory variables and changes in marital fertility that are very similar both before and after the onset of the transition.; no

Health transition research in the control of morbidity and mortality from acute respiratory infection.

Douglas, Robert M; D'ouza, Rennie
Fonte: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University Publicador: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University
Tipo: Artigo de Revista Científica Formato: 32218 bytes; application/pdf
EN_AU
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The essence of health transition research is its multidisciplinary character and openness to broad theory. Theories of health transition provide the context in which classic epidemiological studies can, most effectively, contribute to population health improvement. Acute respiratory infections are a leading cause of morbidity in all countries, and a major cause of premature death in countries where mortality is high. The international ARI control program in childhood sponsored by the World Health Organization is built on conventional biomedical foundations. Health systems in Australia and Pakistan continue to be driven by this conventional model which has contributed to changes in mortality but probably not exclusively. A health transition approach forces us to step back, and place the gains of the biomedical model in a social and historical perspective. Using that perspective to move public health policy forward in the modern nation state requires adventurous lateral thinking. We review here the problem of acute respiratory infections in Australian and Pakistani children. In Australia, we focus on the large differences in respiratory infection severity and outcomes between Aboriginal children and Caucasians. We also draw attention to our current ignorance on what differentiates children who are prone to respiratory infections from those who are not. In Pakistan...

The first generation with mass schooling and the fertility transition: the case of Sri Lanka

Dissanayake, Lakshman
Fonte: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University Publicador: Health Transition Centre, National Centre for Epidemiology and Population Health, The Australian National University
Tipo: Artigo de Revista Científica Formato: 61740 bytes; application/pdf
EN_AU
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This study attempts to explain the Sri Lankan fertility transition in terms of the pre-transition fertility regime and conditions leading to its destabilization. This study therefore deviates from previous studies of fertility in Sri Lanka which have largely focused upon the post-transitional fertility differentials. From the first formulation of demographic transition theory, education has been used as a significant factor relating to the fertility transition, but Caldwell’s ‘mass education fertility transition’ thesis can be regarded as the major attempt to explain the relationship between education and the onset of the fertility transition, with education a central explanatory factor in fertility transition theory. My analysis uses existing fertility theory to explain the educationfertility transition relationship, systematically tests that theory and suggests some modification to the theory on the basis of the Sri Lankan experience. The availability of relevant information in Sri Lanka has provided the opportunity to analyse the generations which contributed to the onset of the fertility transition and the continuance of that transition.; no

Excitonic Analysis of Many-Body Effects on the 1s−2p Intraband Transition in Semiconductor Systems

PARKS, Andrew Marshall
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
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I present a detailed study of many-body effects associated with the interband 1s transition and intraband 1s-2p transition in two- and three-dimensional photo-excited semiconductors. I employ a previously developed excitonic model to treat effects of exchange and phase space filling. I extend the scope of the model to include static free-carrier screening. I also develop a factorization scheme to obtain a consistent set of excitonic dynamical equations. The exciton transition energies are renormalized by many-body interactions, and the excitonic dynamical equations provide simple expressions for the individual contributions of screening, phase space filling and exchange. The effects of exchange and phase space filling are quantified by a set of excitonic coefficients. I first calculate these coefficients analytically by omitting screening effects. In contrast, the screened coefficients involve multi-dimensional integrals which must be evaluated numerically. I present a detailed discussion of the numerical methods used to evaluate these integrals, which include a novel algorithm for segmenting multi-dimensional integration regions. The excitonic model correctly predicts the blue shift and bleaching of the 1s exciton resonance due to exchange and phase space filling. Free-carrier screening is found to enhance these effects by lowering the exciton binding energy. In contrast...

Modélisation systémique de la transition pour les familles ayant un adolescent atteint de fibrose kystique en phase pré-transfert vers l'établissement adulte

Dupuis, France
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Les progrès spectaculaires réalisés dans le traitement de la fibrose kystique font en sorte qu'un nombre de plus en plus élevé de familles comptant un adolescent atteint de ce problème de santé, peut maintenant envisager d'effectuer la transition depuis l'adolescent vers l'âge adulte. À ce jour, les recherches à ce sujet demeurent peu nombreuses, principalement en ce qui a trait à la nature des interations entre les adolescents, leurs parents et les professionnels de la santé qui préparent ces familles en vue du transfert, depuis un établissement pédiatrique vers un établissement adulte. L'appréhension de ce phénomène s'est réalisée dans une perspective constructiviste et systémique, ce qui a permis de mettre en relief certaines des multiples facettes du phénomène et de jeter un éclairage novateur sur des dynamiques entre les membres de la famille et entre ces derniers et les professionnels de la santé. Le but de cette étude de cas, de type qualitavive, était de modéliser de manière systémique, le processus de transtion pour des familles ayant un adolescent atteint de la fibrose kystique qui est en phase pré transfert, depuis l'établissement pédiatrique vers le milieu adulte. Des entretiens semi-dirigés ont été réalisés avec sept familles comptant un adolescent atteint de la fibrose kystique. De plus...

Études spectroscopiques expérimentales et théoriques de complexes de métaux de transition

Lanthier, Etienne
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Cette thèse présente une série d'études qui visent la compréhension de la structure électronique de complexes de métaux de transition en employant diverses méthodes de spectroscopie. L'information sur la structure électronique aide à comprendre et développer des nouveaux matériaux, des nouvelles voies de synthèses, ainsi que des nouveaux modèles théoriques. Habituellement, afin d'explorer la structure électronique d'un système qui comporte en son centre un métal de transition, l'information fournie par les spectres d'un seul composé n'est pas suffisante. On étudie une série de composés similaires, qui ont le même métal de transition à un degré d'oxydation donné, ainsi que des ligands qui forment des liaisons de différentes forces et caractéristiques avec le métal. Cependant, ces changements, bien qu'on les désire de faible impact, créent une grande perturbation de la structure électronique visée par les études. Afin d'étudier en profondeur une seule structure électronique, nous employons une stratégie d'analyse moins perturbante. Nous appliquons une pression hydrostatique sur les complexes de métaux de transition. Cette pression perturbe le système suffisamment pour nous livrer davantage d'informations sur la structure électronique...

Perceptions d’infirmières et infirmiers diplômés à l’étranger et de préceptrices sur les stratégies facilitant la transition professionnelle en période de préceptorat

Boulais, Nicole
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Le nombre d’infirmières et infirmiers diplômés à l’étranger (IIDÉ) est en constante progression au Canada. Le préceptorat est qualifié d’approche exemplaire pour faciliter la transition professionnelle d’IIDÉ dans le nouvel environnement (Sherman & Eggenberger, 2008). Au cours de cette période, les défis pour l’IIDÉ sont importants en raison des différences culturelles et de pratique entre les pays d’origine et d’accueil (Johnston & Mohide, 2008). Une transition réussie est nécessaire pour le bien-être des IIDÉ et leur rétention dans le milieu de travail, mais aussi pour l’impact possible sur la sécurité des patients et la qualité des soins (Kawi & Xu, 2009). Inspirée de la théorie intermédiaire de la transition (Meleis, Sawyer, Im, Messias, & Schumacher, 2000), cette recherche avait pour but de décrire les perceptions d’IIDÉ et de préceptrices, en regard des stratégies utilisées en période de préceptorat, pour contrer les barrières et faciliter la transition professionnelle d’IIDÉ, en milieu de santé québécois. Les résultats de cette recherche descriptive qualitative proviennent de l’analyse d’entrevues semi-dirigées avec six IIDÉ d’origine française et deux préceptrices. Plusieurs stratégies s’adressant à l’IIDÉ...

La transición entre educación infantil y educación primaria: perspectivas y participación de las familias; The transition between early childhood education and primary education: families' perspectives and involvement

Sañudo Ortiz, Rosa María
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Trabalho de Conclusão de Curso
SPA
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RESUMEN La transición educativa entre etapas es un proceso fundamental en la educación de los niños, especialmente, la transición de Educación Infantil a Educación Primaria, puesto que afecta al aprendizaje de los alumnos, a su nivel académico, a su desarrollo social y emocional y contribuye a la facilitación de posteriores transiciones. En este trabajo se ha realizado un estudio bibliográfico, analizando la literatura existente sobre la transición entre Educación Infantil y Educación Primaria desde la perspectiva de los padres a nivel internacional. Dicha investigación surgió con el propósito de dar respuesta a una serie de cuestiones relacionadas con la percepción que tienen los padres sobre la transición, la colaboración y la participación de las familias en los centros escolares, conocer cómo afecta la transición a los padres y comprobar la validez de programas para implicar a las familias en el proceso de transición entre etapas. Los resultados nos muestran en primer lugar, que los padres dan mayor importancia durante la transición a las cuestiones académicas que a otros aspectos como la salud, el bienestar y la curiosidad. En segundo lugar, que a pesar de que las familias y los maestros son conscientes de que la colaboración y coordinación entre ambos colectivos facilitan la transición...

Effects of Selection for the Timing of Vegetative Phase Transition on Corn Borer (Lepidoptera: Noctuidae and Crambidae) Damage

Revilla Temiño, Pedro; Malvar Pintos, Rosa Ana; Velasco Pazos, Pablo; Butrón Gómez, Ana María; Tracy, W. F.; Abedon, B. G.; Ordás Pérez, Amando
Fonte: Entomological Society of America Publicador: Entomological Society of America
Tipo: Artículo Formato: 4085 bytes; image/gif
ENG
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In maize, Zea mays L., the timing of vegetative phase transition from juvenile to adult vegetative phases can be modified through selection. A reduction in the juvenile vegetative phase has been associated with resistance to diseases and pests. The major maize pest in temperate areas is Ostrinia nubilalis (Hübner) and in Europe Sesamia nonagrioides Lefebvre. The objective of our study was to determine the effects of divergent selection for the timing of vegetative phase transition in maize on resistance to corn borers. Three cycles of divergent selection for early and late phase transition in a field corn synthetic and in a sweet corn population were evaluated separately under S. nonagrioides and O. nubilalis artificial infestation. For the field corn experiment, yield and moisture improved with selection for phase transition in both directions, but improvement was due to artifacts of selection, rather than to the change in phase transition. There were no correlated responses for corn borer damage, yield, or grain moisture due to selection for the timing of vegetative phase transition. In the sweet corn experiment, selection for the timing of vegetative phase transition had no significant effects on corn borer damage in sweet corn harvested at the fresh stage. Our results do not support the use of phase transition as an indirect criterion for improving resistance to corn borers in maize. The relationship between phase transition and pest resistance reported by other studies could depend on the genotypes or could be too weak to be detected in a selection program with wild-type maize.; Peer reviewed

Kindergarten transition practices for students with autism spectrum disorder

McCumber, Cassandra
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
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The educational classification of Autism has increased significantly in recent years. Schools are now facing new requirements and expectations to provide appropriate services to meet the needs of students with Autism Spectrum Disorders (ASD). The kindergarten transition is the first major educational transition in a student's educational career. It is a particularly important transition for students with ASD because a successful kindergarten transition leads to better academic outcomes and better generalization of skills developed in the preschool setting (McIntyre et al., 2006). However, students with ASD begin with significant risk of an unsuccessful transition to kindergarten to due to qualitative impairments in social-communication and behavior. The use of recommended practices in kindergarten transition increases the chance of a successful transition for students with ASD. The current study aimed to identify the current use and perceived importance of best kindergarten transition practices for students with ASD, identify barriers of implementing kindergarten transition practices for students with ASD, identify predictors of use of transition practices for kindergarteners with ASD and identify differences on the reported use of transition practices between professional groups and educational settings. A reliable Transition Practices Scale was developed (α= .927) as used as the main measure for the study. It was found that current use of best transition practices is far from optimal despite the high degree of perceived importance. Predictors of the use of transition practices differed somewhat across professional subgroups and settings although regression analyses were limited by low statistical power. No significant differences in the reported use of best transition practices were found across professional subgroups and settings. Although more research is needed...

Megasphaera elsdenii on the performance of steers adapting to a high-concentrate diet, using three or five transition diets

Drouillard,J.S.; Henning,P.H.; Meissner,H.H.; Leeuw,K-J.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
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Megasphaera elsdenii (M.e.) NCIMB 41125 is a robust lactate utilizing strain of M.e. that is effective in minimizing the risk of ruminal acidosis in feedlot cattle. When dosed orally, cattle adapt smoothly to increasing concentrates in the diet, the incidence of digestive disturbances, morbidity and mortality is reduced, and carcass yield improves. One could therefore expect that the smooth transition should benefit overall performance. Dosing with the organism also provides the opportunity of a reduction in the time necessary for adaptation, rendering a further decrease in the cost of feeding. These two objectives were tested with 80 yearling crossbred steers blocked by weight before allotment to the respective treatments. The trial design was a randomized 2 χ 2 factorial of two drench treatments (M. e. vs. placebo) and two adaptation periods (17 vs. 8 days). In the M.e. treatment, 40 steers were dosed orally on day 1 of the trial with 200 mL inoculum containing 10(11) cells. In the placebo treatment, the other 40 steers were dosed orally with only the 200 mL inoculum. In the 17-day transition period, five diets (5-transition) were used, which increased progressively in concentrate percentage, whereas in the 8-day transition period only three of the five diets were fed (3-transition). The steers were fed individually for 63 days before being transferred to group pens and fed until day 95...