Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Errata slip inserted. Includes bibliographical references.

München, Techn. Univ., Diss., 2001. / Computerdatei im Fernzugriff.

München, Techn. Universiẗat, Diss., 2001.

Digital medieanvändning ökar hos både barn och vuxna mer och mer i vår vardag, både i hemmet och utanför. Forskning tyder på att barnets språkliga utveckling påverkas av både den digitala miljön i hemmet men också av hur mycket och på vilket sätt föräldrar läser för och interagerar med barnet, det vill säga kognitiv, språklig och läsfrämjande stimulans i hemmiljön (KSL i hemmiljön). Denna studie ämnade, via en föräldraenkät, undersöka hur barnens digitala medieanvändning samt kognitiv, språklig och läsfrämjande stimulans i hemmiljön samvarierar med barnens språkutveckling. I studien deltog 166 föräldrar med barn i åldrarna 3-5 år (91 pojkar och 75 flickor). Föräldrarna fick svara på en skattningsenkät som undersökte digital medieanvändning (MAQ), kognitiv, språklig och läsfrämjande stimulans i hemmiljön (STIMQ-2) samt barnets språkliga utveckling (SECDI-III). Studiens resultat visar på flera intressanta samband hos barn i 3-5 årsåldern, bland annat mellan barns språkutveckling och deras medieanvändning. Barnets språk visar på signifikanta skillnader men också barnets användande av digitala media, som ökar signifikant från cirka 1 timme per dag vid 3 års ålder till nära 2 timmar per dag vid 5 års ålder. Genom hierarkiska regressionsanalyser med ålder, kön och föräldrars inkomst som kontrollvariabler kunde en del av den språkliga utvecklingen (5.2-11.6%) förklaras av en negativ påverkan av barnets medieanvändning och en positiv påverkan av föräldrars kognitiva, språkliga och läsfrämjande stimulans i hemmiljön. Resultaten indikerar att det är värdefullt att undersöka detta ämne ytterligare i en population med föräldrar som har en varierad utbildningsbakgrund.

Comparison of the observed and calculated vibrational frequencies of all-trans-octatetraene indicates that the density functional theory (DFT) using Becke's exchange and Lee-Yang-Parr's correlation functionals is as accurate as the Hartree-Fock (HF)-based scaled quantum mechanical force field approach in predicting fundamental vibrational frequencies. As the DFT calculation does not use any empirical parameters pertaining to the subject molecule and its computational cost scales more favorably than that of the HF theory, it is a more promising approach to molecular vibrational problems and should replace the empirical normal coordinate analysis for assisting vibrational assignments.

An early childhood assessment tool was developed by the author to fill a need for an observational, authentic, child assessment instrument that would include the measurement of social and emotional development, help guide teachers towards best curriculum practices, and meet common criteria for effective, appropriate, and equitable assessment. Theoretical constructs of interactionalism, multiple intelligences, dispositions, and developmentally appropriate practices were used to inform the construction of the tool. In addition, the author hoped to develop a tool that would be effective for use as a Head Start program evaluation research instrument. Research methods involved a representative random sample of 200 children in four early childhood programs in two northwest states and the use of two different surveys, one completed by 15 early childhood experts and one by 114 users of the assessment. The Oregon Assessment was found to be an instrument with an acceptable degree of item, curricula, and construct validity; a high level of test-retest, inter-rater, and internal reliability (coefficient alpha = .879); and an acceptable degree utility. Only one item out of 60 was found to have low item validity, and three other items were rated lower than others (although generally positive) on both item and curricula validity. It was found to have significant but moderate congruent validity with total scores on The McCarthy Scales for Children and The Vineland Adaptive Behavior Scales. Users throughout the U.S. found it generally useful – nearly 87 of respondents agreed or strongly agreed that the results accurately reflect the skills, behaviors, and abilities of their children. The length of time it takes to administer emerged as a concern from some users. Recommendations were made to refine the instrument and user manual and to develop a shorter version. It was found to have great potential use as a research instrument for program evaluation and for promoting best practices in early childhood programs.

Syftet med det här examensarbetet var att undersöka 3-5 åringars förmåga att utveckla sin förståelse för vattnets väg till kranen genom med en pedagogisk aktivitet. Genom den pedagogiska aktiviteten gavs barnen möjlighet att färdas genom vattensystemet med sina kroppar och sinnen, från sjön till kranen. För att kartlägga hur barnens förståelse utvecklats genomfördes kvalitativa intervjuer före och efter den pedagogiska aktiviteten.Jämförelsen mellan resultaten av förintervjuerna och uppföljningsintervjuerna pekar på en tydlig utveckling av barnens förståelse av vattnets väg till kranen, som ett tekniskt system. Flera av barnen utvecklade sin förståelse för att vårt hushållsvatten måste genomgå en reningsprocess, färdas genom olika komponenter i vattensystemet och rör innan det slutligen når kranen och kan förtäras. / The purpose with this degree thesis was to examine 3-5 year old´s ability to develop their understanding of the path of the water to the tap through an educational activity. Through the educational activity the children was given the opportunity to travel through the water system with their bodies and senses, from the lake to the tap. Qualitative interviews were carried out before and after the educational activity to map out the children´s understanding and how it had developed after the educational activity.The comparison between the results of the pre-interviews and follow-up interviews indicate a clear development of the children´s understanding of the path of water to the tap, as a technical system. Several of the children developed the understanding that our domestic water must undergo a purification process, travel through various components of the water system and pipes before it finally reaches the tap and can be ingested.

Orientador: Marcelo Palma Sircili / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T15:41:18Z (GMT). No. of bitstreams: 1 Higa_JulianaSuyama_M.pdf: 2740628 bytes, checksum: 20ced0f2848628f2541d4313632cfc0b (MD5) Previous issue date: 2015 / Resumo: Escherichia coli (E.coli) enteropatogênica (EPEC), é um dos agentes causadores de diarreia em crianças, principalmente em países em desenvolvimento. EPEC pode ser dividida em típica (tEPEC) ou atípica (aEPEC) pela presença ou ausência do plasmídeo EAF, respectivamente e, mais precisamente pela expressão da fímbria Bfp. Uma característica de EPEC é a capacidade de causar uma lesão histopatológica denominada "attaching and effacing" (lesão A/E) no epitélio intestinal e os genes responsáveis pela formação da lesão A/E estão localizados na ilha de patogenicidade LEE (locus of enterocyte effacement). Outra característica de EPEC é a formação de microcolônias que possibilitam a formação de biofilme. Um dos mecanismos de regulação da formação de biofilme envolve a molécula sinalizadora Bis-(3'-5')-monofosfato de guanosina cíclico (c-di-GMP), um mensageiro secundário universal em bactérias que está envolvido na regulação de uma grande variedade de processos celulares. Para exercer sua função, c-di-GMP precisa se ligar e alterar alostericamente a estrutura de uma molécula efetora. Um dos receptores conhecidos para c-di-GMP é YcgR, uma proteína de domínio PilZ que possui um sítio de ligação para c-di-GMP e está envolvida diretamente na regulação do movimento flagelar através da ligação do complexo YcgR-c-di-GMP às proteínas da base do motor flagelar. Existem poucos dados na literatura sobre as funções de YcgR, todos focados apenas no seu papel na regulação da motilidade. Assim, o presente trabalho teve como objetivo avaliar a influência de YcgR na motilidade, formação de biofilme, adesão e formação de lesão A/E em um amostra de aEPEC do sorotipo O55:H7. O gene ycgR foi deletado da amostra selvagem através da técnica de recombinação homóloga proposta por Datsenko e Wanner (2000). A complementação da amostra mutante foi realizada através da clonagem do gene ycgR no plasmídeo de expressão pBAD Myc HisA. Os resultados obtidos indicam que a deleção do gene ycgR reduz a motilidade e aumenta a formação do biofilme inicial na amostra O55:H7. Além disso, a adesão em células epiteliais e a formação da lesão A/E também foram reduzidas em comparação à amostra selvagem. Os resultados fenotípicos corroboram os observados na análise transcricional dos genes eae, ler e espA, que participam da formação da lesão A/E, e dos genes bscA, fimA e csgD, envolvidos na formação do biofilme inicial. Com exceção do gene csgD que apresentou um aumento na transcrição na amostra mutante, todos os outros genes avaliados apresentaram uma menor transcrição em relação à amostra selvagem. Poucos trabalhos na literatura demonstram o papel do mensageiro secundário em amostras de E. coli patogênicas, assim, estes resultados são os primeiros descritos para uma amostra de aEPEC e possibilitam que no futuro novos estudos possam analisar com mais detalhes a participação de c-di-GMP na regulação de fatores de virulência não só de aEPEC mas também de outras E.coli patogênicas / Abstract: Enteropathogenic Escherichia coli (EPEC) is a causative agent of diarrhea in children, especially in developing countries. EPEC can be categorized in 2 subgroups termed typical (tEPEC) or atypical (aEPEC) by the presence or absence of the EAF plasmid respectively, and more precisely by the expression of the Bfp fimbriae. One characteristic of EPEC is the ability to cause a histopathological lesion on epithelial cells called "attaching and effacing" (A/E lesion). The genes responsible for the production of the A/E lesion are encoded in a pathogenicity island named "locus of enterocyte effacement" (LEE). Another feature of EPEC is the formation of microcolonies, which allow biofilm formation. One of the regulation mechanisms of biofilm formation involves the signaling molecule bis- (3'-5') cyclic guanosine monophosphate (c-di-GMP), a ubiquitous second messenger in bacteria that participates in the regulation of a wide variety of cellular processes. To perform its function, c-di-GMP needs to bind and alter allosterically the structure of an effector molecule. One of the known (many?) receptors for c-di-GMP is YcgR, a Pilz domain protein that has a c-di-GMP binding site and is involved directly in the regulation of flagellar movement through the binding of the YcgR-c-di-GMP complex to flagellar motor proteins. There are few published data on the YcgR functions and they focus mainly on the role of the YcgR in motility regulation. The aim of this study was to evaluate the influence of YcgR in motility, biofilm formation, adhesion and A/E lesion formation in an aEPEC strain serotype O55:H7. ycgR gene deletion was performed by homologous recombination as proposed by Datsenko and Wanner (2000). Complementation of O55:H7 mutant strain was achieved by cloning ycgR in pBAD/Myc-HisA plasmid. The results indicate that the deletion of ycgR gene decreases the motility and increases the formation of initial biofilm on O55:H7 strain. Moreover, the adhesion on epithelial cells and the A/E lesion formation were also diminished in comparision to the wild type strain. The phenotypic results are consistent with the transcriptional analysis of eae, ler and espA genes involved in A/E lesion formation, and of bcsA, fimA and csgD genes involved in the initial steps of biofilm formation. With the exception of csgD gene that showed an increased transcription level in the mutant strain, all other analysed genes showed a decrease in transcription when compared to the wild type strain. Few studies demonstrate the role of a second messenger molecule in Escherichia coli pathogenic samples, and therefore, these results are the first report in this regard for an aEPEC strain. This work should encourage further studies in order to analyze in more detail the involvement of c-di GMP in the regulation of virulence factors not only in aEPEC, but also in other pathogenic Escherichia coli pathotypes / Mestrado / Microbiologia / Mestra em Genética e Biologia Molecular

Les troubles anxieux sont les troubles psychologiques les plus prévalents chez les enfants et les adolescents. Les symptômes apparaissent rapidement dans le développement de l’enfant et persistent souvent jusqu’à l’âge adulte. Plusieurs recherches ont été réalisées sur les prédicteurs de l’anxiété. Certaines font ressortir une association entre l’attachement insécurisant et l’anxiété, particulièrement les attachements ambivalent et désorganisé. Depuis quelques années, un nouveau concept est utilisé pour évaluer la relation parent-enfant, la relation d’activation. Cette dernière est complémentaire à la relation d’attachement, car elle considère les dimensions de la discipline et de la stimulation à la prise de risque, alors que l’attachement est basé sur la dimension du réconfort. Plusieurs recherches ont aussi trouvé des associations entre l’anxiété et l’activation. De ce fait, le premier objectif de cette recherche est de déterminer quelle association est plus forte avec l’anxiété entre la relation d’attachement ou la relation d’activation. Le deuxième objectif est de vérifier si le sexe du parent est un modérateur de l’association entre l’anxiété et les deux relations. L'échantillon est composé de 38 parents et de leurs enfants, âgés de 3 à 5 ans. Les instruments de mesure utilisés sont l’échelle d’anxiété/dépression du questionnaire CBCL pour les scores d’anxiété, la situation étrangère pour l’attachement et la situation risquée pour la relation d'activation. Les résultats montrent que la relation d’activation est associée à l’anxiété, alors que ce n’est pas le cas pour la relation d’attachement. De plus, le sexe du parent n’est pas un modérateur des associations entre l’anxiété et les relations. / Anxiety disorders are the most prevalent disorders in children and adolescents. The symptoms appear quickly in the child's development and often persist into adulthood. Many researches have been conducted on the predictors of anxiety. Several studies show that there is an association between insecure attachment and anxiety, particularly ambivalent and disorganized attachment. In recent years, a new concept has been used to evaluate the parent-child relationship, the activation relationship. This new measure is complementary to the attachment relationship because it considers the dimensions of discipline and stimulation to risk taking, while attachment is based on the dimension of comfort. Several studies have also found associations between anxiety and activation. As a result, the primary goal of this research is to determine which association is stronger with anxiety: attachment or activation. The second objective is to understand if the parent's sex is a moderator of the association between anxiety and the two relationships. The sample is composed of 38 parents and their children, aged 3 to 5 years. The measuring instruments used are the anxiety/depression scale of the CBCL questionnaire for the anxiety scores, the strange situation for attachment and for the activation relationship, the risky situation. The results show that the activation relationship is associated with anxiety, whereas this is not the case for the attachment relationship. In addition, the parent's gender is not a moderator of the associations between anxiety and attachment or activation relationships.

La réduction de l’expression de deux gènes codant pour la L-galactono-lactone-1,4-déshydrogénase (GalLDH) et de la GDP-D-mannose-3’,5’-épimérase (GME), enzymes de la voie de biosynthèse de l’ascorbate, a permis de mieux comprendre le rôle physiologique de ces enzymes chez la tomate. D’une part, l’étude de la GalLDH a mis en évidence la régulation complexe du métabolisme de l’ascorbate et la fonction essentielle de cette protéine au sein de la chaîne de transport des électrons au niveau mitochondrial. D’autre part, ce travail a révélé le rôle central de la GME à la fois pour la biosynthèse de l’ascorbate et la biosynthèse des polysaccharides pariétaux, notamment les mannanes et le rhamnogalacturonane II. Chez les plantes sous-exprimant la GME, nous avons pu noter l’incidence de perturbations de la structure pariétale sur les propriétés mécaniques des tiges et des fruits ainsi que sur la fécondation. Ces modifications ont notamment engendré une fragilité accrue des tiges et une stérilité partielle. La GME est donc déterminante pour la qualité nutritionnelle et organoleptique du fruit de tomate. Enfin, dans le cadre d’une approche de biologie intégrative, nos résultats associés aux données issues de plantes sous-exprimant des gènes codant pour des enzymes de la voie de recyclage de l’ascorbate chez la tomate ouvrent des perspectives originales pour l’approfondissement des connaissances sur la régulation et sur l’intégration du métabolisme de l’ascorbate dans le fonctionnement de la cellule. / Down-regulation of two genes encoding the L-galactono-1,4-lactone dehydrogenase (GalLDH) and the GDP-D-mannose-3',5'-epimerase (GME), enzymes of ascorbate biosynthesis pathway, led to a better understanding of the physiological role of these enzymes in tomato plants. On one hand, the study of GalLDH highlighted the complex regulation of ascorbate metabolism and the essential function of this protein in mitochondrial electron transport chain. Moreover, this work revealed the central role of the GME for both the ascorbate biosynthesis and the biosynthesis of cell wall polysaccharides, including mannans and rhamnogalacturonan II. In the GME-silenced plants, we found that modifications of the cell wall structure change the mechanical properties of stems and fruit as well as the fertilization. These changes led to an increase of stem fragility and to an increase of sterility. Therefore, GME plays a crucial role regarding the nutritional and organoleptic quality of tomato fruit. Finally, within the context of a systems biology approach, our results associated to datas obtained with plants silenced for recycling pathway related genes lead to the prospect to unravel the knowledges on the regulation and the integration of ascorbate metabolism in cell functions.