La fumée de tabac contient la nitrosamine 4-(méthylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) qui serait impliquée dans la cancérogenèse pulmonaire. L'?-hydroxylation de la NNK génère deux métabolites réactifs qui mènent à la méthylation et à la pyridyloxobutylation de l'ADN, et qui peuvent être générés respectivement par la N-acétoxynitrosométhylméthylamine et par la 4-(acétoxyméthylnitrosamino)-1-(3-pyridyl)-1-butanone. Nous avons observé que la fréquence et la distribution des dommages induits à l'ADN par la méthylation et la pyridyloxobutylation au niveau des gènes p53, ras et c-jun ne sont pas identiques. La fréquence et la distribution des dommages par la méthylation de l'ADN varient avec la classe et la structure chimique des agents méthylants. La pyridyloxobutylation de l'ADN induit des cassures monocaténaires caractérisées par un groupement hydroxyle à l'extrémité 5' et par un groupement bloquant à l'extrémité 3'. La formation de dommages causée par la NNK et la fréquence élevée de dommages à certaines positions nucléotidiques qui correspondent à des positions fréquemment mutées dans le cancer pulmonaire chez le fumeur constitueraient des arguments en faveur d'un rôle de la NNK dans la cancérogenèse pulmonaire associée à la fumée de tabac.

I denna studie eftersträvar vi att utvidga vår uppfattning till hur olika lärare i årskurs 1–3 resonerar vid användningen av digitala verktyg och läromedel i undervisningen av de samhällsorienterade ämnena och dess möjligheter respektive utmaningar. Empirin baserades på sex olika klasslärares subjektiva uppfattningar kring digitala verktyg och läromedel, vilket genomfördes med hjälp av en kvalitativ metod. Studien utgick från läroplansteorin för att ta reda på hur läraren implementerar digitalt material i SO-undervisningen samtidigt som läroplanen tas till hänsyn. Studiens resultat tydliggör att lärarna använder sig av liknande arbetssätt och material som anses stötta elevens kunskapsutveckling, vilket avgörs till största del på lärarens digitala kompetens samt didaktiska kunskaper. Studiens slutsats är att trots olika ramfaktorer och digitala kunskaper bör läraren se till att implementera digitalt material på ett sätt som kompletterar lärarens undervisning, för ett effektivt lärande.

La fumée de tabac contient plusieurs substances carcinogènes qui mènent à la formation constante de petites quantités de dommages à l'ADN dans les poumons des fumeurs ainsi que des non-fumeurs exposés à la fumée environnementale de tabac. La 4-(méthylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) est l'une de ces substances et elle semble plus particulièrement associée avec le développement des adénocarcinomes, la forme de cancer pulmonaire dont l'incidence progresse le plus rapidement ces dernières années. Dans les cellules pulmonaires, la NNK est bioactivée via des cytochromes P450 en intermédiaires réactifs capables de méthyler ou de pyridyloxobutyler l'ADN. Les dommages résultant de ces deux modes d'activation de la NNK peuvent être investigués séparément en utilisant des analogues qui génèrent sélectivement l'un ou l'autre type d'intermédiaires réactifs. Le test des comètes est une technique simple, très sensible et couramment utilisée pour étudier au niveau cellulaire les dommages à l'ADN qui sont peu fréquents. Les travaux présentés dans cette thèse montrent que certains des dommages résultant de l'activation de la NNK peuvent être investigués de manière spécifique à l'aide de cette technique, et ce à des fréquences de dommages qui se rapprochent de celles correspondant à une exposition réelle à la fumée de tabac. Parmi ces dommages, un type d'adduits encore inconnu associé à la pyridyloxobutylation de l'ADN a pu être mis indirectement en évidence. Il s'agit vraisemblablement de la forme formamidopyrimidine (fapy) d'une lésion primaire formée dans les cellules. La vitesse de réparation d'un type de dommage influe sur le risque qu'il a d'être impliqué dans la transformation maligne des cellules. La disparition des dommages dans le temps a pu être suivie avec le test des comètes afin d'investiguer la réparation dans des cellules capables ou pas de bioactiver la NNK. Le suivi post-traitement des dérivés fapy associés à la pyridyloxobutylation de l'ADN, a montré un phénotype ne dépendant pas du type cellulaire mais plutôt du statut de p53 dans les cellules. En effet, au lieu de diminuer après la fin du traitement, la fréquence des adduits fapy dans les fibroblastes augmente dans un premier temps et ce, seulement dans les cellules ayant une protéine p53 fonctionnelle. La nature de ce phénotype particulier n'est pas clairement identifiée, mais elle est vraisemblablement liée à la réparation des dommages à l'ADN. / Tobacco smoke contains several carcinogens that lead to the frequent formation of rare DNA damage in lungs of smokers. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of these substances that seems more particularly associated with the development of adenocarcinoma. During the last 30 years, the frequency of this lung cancer type has increased significantly. In lung cells, cytochromes P450 can bioactivate NNK into reactive species capable of either methylating or pyridyloxobutylating DNA. The use of analogs capable of generating only one type of NNK-associated reactive species allows to investigate methylation and pyridyloxobutylation separately. The comet assay is a simple and sensitive technique that is commonly used to investigate low frequency DNA damage at the cellular level. The work presented here show how some of the NNK-related DNA damage can be investigated specifically with this technique at damage frequencies that are relevant to a real exposure to cigarette smoke. One of the adduct type resulting of DNA pyridyloxobutylation that we studied here had never been demonstrated before. It corresponds likely to the formamidopyrimidine (fapy) form of a lesion primarily formed in cells. The repair rate of a damage type influences the probability that it has to be implicated in mutagenesis. The time course of different damage types was documented with the comet assay in order to investigate the repair of NNK-related damage in different cell types that can either bioactivate NNK or not. When the fapy adducts associated with pyridyloxobutylation were investigated post-treatment, their time course did not depend on the cell type but showed a p53-dependant phenotype. In fact, instead of decreasing because of repair, the frequency of these fapy adducts in fibroblasts first increased post-treatment and this increase seemed associated with p53 proficiency. The cause of this phenotype is not clearly elucidated but it should be related to DNA damage repair.

Syftet med denna studie är att få en fördjupad förståelse av hur en förskola kan arbeta med ämnena naturvetenskap och teknik på ett genomtänkt sätt. Avsikten med studien är också att bidra med mer kunskap om på vilka olika sätt pedagoger kan ta tillvara och utveckla barnens intresse för teknik och fysik. Studien är kvalitativ och har genomförts genom att studera dokumentation från sociala medier som den studerade förskolan publicerat. Dokumentationen har sedan varit en grund för de semistrukturerade intervjuer som genomfördes. För att komma fram till resultatet som gjorts har den fenomenografiska analysmodellen använts. Resultatet som framkom ifrån de tre intervjuer som gjordes, visar att pedagogerna på denna förskola inte ser några hinder med att arbeta med ämnena naturvetenskap och teknik med de allra yngsta barnen, 1–3 år, trots att de saknar en formell fördjupad utbildning inom ämnena. Pedagogerna ser bara möjligheter. Förskolan arbetar Reggio Emilia inspirerat och har arbetat fram en praktikgemenskap, där de skapar goda förutsättningar för undervisning i naturvetenskap och teknik. / The aim of this study is to gain an in-depth understanding of how a preschool can work with the subjects of science and technology in a well-thought-out way. The purpose of the study is also to provide more knowledge about which different ways pedagogues can use and develop the children's interest in technology and physics. The study is qualitative and has been carried out by studying documentation from social media published by the preschool. The documentation has since been a basis for the semi-structured interviews that were conducted. To reach the result, the phenomenographic analysis model has been used. The result shows that the three teachers interviewed at this preschool see no obstacles to working with the subjects of science and technology with the youngest children, 1-3 years, even though they lack a formal in-depth education in the subjects. The preschool teachers only see opportunities. To create the best conditions for teaching science and technology the preschool has worked out a community of practice inspired by Reggio Emilia.

I de fall enskilda aktieägare tillfogas skada, genom organledamots handlande, innehar dessa rättigheten att påkalla skadeståndsansvar enligt 29:1 1 st. 2 men. ABL. I den svenska rättstillämpningen ter sig dock tillämpningen av paragrafen, i samband med indirekta skador, problematisk. Problematiken hänför sig till vilka regler, vars åsidosättande, aktualiserar tillämpningen av paragrafen tillsammans med aktieägares talerätt. Två tolkningar kan i fallet identifieras, vilka framförts inom doktrinen, varvid en begränsad och en mer liberal. Även om den liberala tolkningen är förenad med viss problematik, är denna enligt mitt förmenande den vilken bör tillämpas. En sådan tillämpning skulle således innebära att enskilda aktieägare tillerkänns talerätt vid indirekt skada, då regler vilka ger uttryck för normskyddsläran och bolagsledningens lojalitetsplikt åsidosatts. Rättsutvecklingen har vidare givet upphov till frågan, huruvida en ”indirekt” indirekt skada kan omfattas av paragrafens tillämpningsområde. En sådan skada uppstår särskilt i koncernförhållanden då dotterbolaget tillfogas en direkt skada, vilken därigenom åsamkar aktieägarna i dess moderbolag en ”indirekt” indirekt skada. Skadan faller utanför paragrafens tillämpningsområde, då de skadedrabbade inte utgör aktieägare i dotterbolaget. En lösning enligt mitt förmenande, varigenom paragrafens tillämpning koncernanpassas, är att principen om ansvarsgenombrott i betydelsen genomsyn nyttjas. Principens aktualisering medför att ett moder- och dotterbolag betraktas som en juridisk enhet, om erforderliga rekvisit uppfylls, varigenom de skadedrabbade aktieägarna från ett teoretiskt perspektiv även ses som aktieägare i dotterbolaget. Effekten av principens tillämpning är sålunda att en ”indirekt” indirekt skada faller inom paragrafens tillämpningsområde. / Whenever individual shareholders inflict an injury, due to action taken by a corporate member, they possess the right to impose liability in accordance with 29:1 1 st. 2 men. ABL. The paragraph is though associated with some difficulties when it comes to an indirect injury. The difficulties regard which rules that have to be infringed, in order for the paragraph to be applicable and thereby providing shareholders with the right to sue. Two different interpretations can hereby be identified, whereby one limited and the other one more liberal. Even if the liberal interpretation is associated with some difficulties, I find that this one should be applied. Such an application would mean that an individual shareholder acquire the right to sue, for an indirect injury, when rules protecting a third person and the corporate member’s duty of loyalty have been infringed. Legal progress has also given rise to another question, whether an “indirect” indirect injury falls within the paragraphs application. Such an injury is mostly affiliated with corporate groups where the daughter company causes a direct injury, whereby the shareholders in the mother company causes an “indirect” indirect injury. Since the shareholder here is not an owner of the daughter company, the paragraph could not be applied. A solution to this problem is, according to me, an application of the principle piercing the corporate veil, whereby the paragraphs application extends to corporate groups. The effect of the principles application is that a mother- and daughter company becomes one legal entity, if the prerequisites are fulfilled. The outcome is hereby that a shareholder in the mother company, from a theoretical perspective, also is regarded to be an owner of the daughter company. Wherefore an “indirect” indirect injury hereby falls within the scope of the paragraphs application.

Made available in DSpace on 2014-06-11T19:32:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-06Bitstream added on 2014-06-13T21:05:14Z : No. of bitstreams: 1 vasconcelos_afd_dr_rcla.pdf: 873436 bytes, checksum: e2a838b6410dbd9cdc2bc380f1261e4e (MD5) / Exopolissacarídeos do tipo β-glucanas são polímeros produzidos por uma grande variedade de microrganismos e podem possuir diferentes propriedades físicas, químicas e aspectos estruturais. Esses biopolímeros apresentam atividades biológicas interessantes (antitumor, antiviral, anticoagulante) e aplicações comerciais como produtos em alimentos, cosméticos e farmacêuticos. Entretanto, para a aplicação dessas moléculas, é necessário primeiramente o conhecimento de suas estruturas químicas. Assim, o objetivo deste trabalho foi a produção, caracterização química de quatro exopolissacarideos (EPSGRAVIOLA, EPSMANGA, EPSPINHA e EPSLARANJA) de isolados de Botryosphaeria obtidos de frutas tropicais em decomposição e crescidos em sacarose como única fonte de carbono, determinando o melhor EPS para realizar testes de atividade anticoagulante. A homogeneidade de cada EPS foi determinada por cromatografia de filtração em gel, os quais eluíram como um único pico. Hidrólise ácida total e análise por HPAEC/PAD mostrou glucose como constituinte básico. Dados de metilação e RMN de 13C indicaram que os EPSMANGA, EPSPINHA e EPSLARANJA são glucanas lineares unidas por ligações do tipo β(1®6) e o EPSGRAVIOLA é uma glucana com ligações β(1®3) e com ramificações em C-6 de resíduos glucopiranosídicos. O espectro de FT-IR mostrou uma banda em 891 cm-1, e a espectroscopia de 13C NMR mostrou que todas as ligações eram do tipo β. Estudos realizados com o corante Vermelho Congo indicaram que os EPS possuem conformação em tripla hélice. O EPSLARANJA, uma b- D-(1®6)-glucana, foi submetido a sulfatação visando induzir a atividade anticoagulante e melhorar a solubilidade da molécula em solução, importante para a atividade biológica. Espectros de FT-IR mostraram bandas em 808 and 1252 cm-1, indicando a entrada dos grupos sulfato e as análises de RMN de 13C mostraram... / Exopolysaccharides (EPS) as β-glucans are polymers produced by a great variety of microorganisms and can possess different physical and chemical properties, and structural features. These biopolymers having interesting biological activities (antitumor, anti-viral, anticoagulant), and commercial applications in foods, cosmetics and pharmaceutical products. However, for the applications of these macromolecules, it is first necessary to understand their chemical structures. Therefore the goal of that study was the production, chemical characterization and biological activity of four exopolysaccharides (EPSGRAVIOLA, EPSMANGO, EPSPINHA and EPSORANGE) obtained from Botryosphaeria strains isolated from rotting tropical fruit grown on sucrose as carbon and the best EPS was used for the anticoagulant activity The homogeneity of each EPS was determined by gel filtration chromatography, which was eluted as a single peak. Total acid hydrolysis and HPAEC/PAD analysis of each EPS yielded only glucose. Data from methylation analysis and 13C NMR spectroscopy indicated that the EPSMANGO, EPSPINHA and EPSORANGE consisted of a linear chain of (1-6)- linked glucopyranosyl residues and EPSGRAVIOLA consisted of a main chain of glucopyranosyl (1-3) linkages substituted at O-6. FTIR spectra showed one band at 891 cm-1, and 13C NMR spectroscopy showed that all glucosidic linkages were of the β-configuration. Dye-inclusion studies with Congo Red indicated that each EPS existed in a triple-helix conformational state. The EPSORANGE, a β-(1®6)- D-glucan was submitted to a sulfation to induce anticoagulant activity and also to make this EPS more soluble, which is in favor to its biological action. The FT-IR spectrum showed bands at 808 and 1252 cm-1 indicating insertion of sulfonyl groups and the 13C NMR analysis showed that the sulfonyl groups were inserted mainly in C-4 of the b(1®6)-D-glucan... (Complete abstract click electronic access below)

No description available.

Hyalella azteca, an amphipod crustacean, is frequently used in freshwater toxicity tests. Since the mid-1980s, numerous organizations have collected and established cultures of H. azteca originating from localities across North America. However, H. azteca is actually a large cryptic species complex whose members satisfy both the biological and the phylogenetic species concepts. Recently, two publications reported that members of the H. azteca cryptic species complex have different toxicity responses to anions and an insecticide. In this study, four members of the H. azteca species complex were identified with DNA barcoding. The genetic variation among the four clades was consistent with interspecific distances between species. These lineages (clades 1, 3, 6, and 8) were cultured in identical conditions and monitored on a weekly basis to determine two life history traits: adult mortality and juvenile production. The large-bodied clades had significantly better survival and juvenile production compared to the small-bodied clade 3. Clade 6 had very low juvenile production and high mortality; therefore, was not included in this study. Unique culture protocols may be required for each clade to optimize growth, survival, and juvenile production in laboratory conditions. Genetic barcoding has identified only two clades in a survey of 17 laboratories. Therefore these two clades (1 and 8) were compared after exposure to copper and nickel 14-day toxicity tests. Clade 8 was 2.3-2.6 times more tolerant to copper exposure than clade 1 based on their LC50 and LC25. Similarly, clade 8 was more tolerant to nickel exposure than clade 1: LC50 was 1.8 times higher for the former. Nickel LBC50 and LBC25 were significantly different between clades by a factor of 2.1-2-8. Mortality (relative to copper concentrations in tissue), growth, and bioaccumulation responses were not significantly different based on overlapping confidence intervals. Although clades 1 and 8 are both large-bodied ecomorphs, these lineages had significantly different body mass (i.e., dry weight) after 14 days. The results of this study indicate that genetically characterized cultures of H. azteca should be used in toxicity tests.

Detta examensarbete handlar om lärares syn på lässtrategiundervisning. Då mina egna erfarenheter inom skolans årskurs 1–3 vittnar om att läsfixarna används som metod trots att det inte finns forskning som stödjer metoden, har intresset legat i att undersöka lärares syn på läsfixarna som metod. Ett hett ämne inom skoldebatten har länge varit svenska elevers sjunkande resultat i läsförståelse enligt kunskapsmätningar som PISA. Detta menar Barbro Westlund, lektor i läs- och skrivutveckling och deltagare i flera forskningsprojekt, beror på bristande förmåga att plocka fram de rätta strategierna i mötet med olika texttyper. Westlund betonar vikten av att undervisa om lässtrategier ämnesspecifikt vilket ökade mitt intresse av att även undersöka hur lärare använder läsfixarna i samhälls- och naturorienterande ämnen. Undersökningen bygger på sju intervjuer av verksamma lärare i årskurs 1–3 samt en observation av ett lektionstillfälle. Resultatet visar en positiv syn på läsfixarna som metod som går att knyta till tidigare forskning. Resultatet har även visat på att metoden till största del används i svenskämnet, men att det på flera sätt går att använda strategierna ämnesspecifikt. Den positiva synen på läsfixarna som metod väcker nya frågeställningar om varför det saknas vetenskapliga bevis på att metoden är effektiv för läsförståelseutveckling. Det här är dock något som öppnar nya dörrar för vidare undersökningar i bredare omfattning på huruvida läsfixarna som metod hjälper läsaren att utveckla läsförståelse eller inte. / This master thesis is about the teachers view of reading strategy teaching. As my own experiences within the school grades 1-3 testifies that “läsfixarna”, which is a method of reading comprehension strategies, as method is used despite there existing no research that supports the method. For this reason, thesis aims to investigate the teachers’ view of “läsfixarna” as a method. A hot topic in school debate has been for a long time the decreasing results for reading comprehension for Swedish students in knowledge test like the PISA test. This is a cause according to Barbro Westlund, a senior lecturer in reading and writing development and participant in multiple research projects, of the lack of ability to use the correct strategies when encountering different kinds of text. Westlund emphasizes the importance of teaching about the reading strategies specific to the study which increased the interest to also investigate on how teachers use “läsfixarna” in society and science studies. The present study is based on seven interviews with working teachers in grades 1-3 and an observation of a period. The results are show a positive view of “läsfixarna” as a method which is also connected to earlier research of reading comprehension strategies. The results also suggest that the method is largely used in the Swedish subject, but it is also possible to use the strategies in various subject-specific ways. The positive view of “läsfixarna” as a method raises new issues, as there is no scientific evidence that the method is effective for reading comprehension development. This is something that opens doors for further and new investigations to a much wider extent on whether “läsfixarna” as a method help readers to develop reading comprehension or not.

Resumo: Exopolissacarídeos do tipo β-glucanas são polímeros produzidos por uma grande variedade de microrganismos e podem possuir diferentes propriedades físicas, químicas e aspectos estruturais. Esses biopolímeros apresentam atividades biológicas interessantes (antitumor, antiviral, anticoagulante) e aplicações comerciais como produtos em alimentos, cosméticos e farmacêuticos. Entretanto, para a aplicação dessas moléculas, é necessário primeiramente o conhecimento de suas estruturas químicas. Assim, o objetivo deste trabalho foi a produção, caracterização química de quatro exopolissacarideos (EPSGRAVIOLA, EPSMANGA, EPSPINHA e EPSLARANJA) de isolados de Botryosphaeria obtidos de frutas tropicais em decomposição e crescidos em sacarose como única fonte de carbono, determinando o melhor EPS para realizar testes de atividade anticoagulante. A homogeneidade de cada EPS foi determinada por cromatografia de filtração em gel, os quais eluíram como um único pico. Hidrólise ácida total e análise por HPAEC/PAD mostrou glucose como constituinte básico. Dados de metilação e RMN de 13C indicaram que os EPSMANGA, EPSPINHA e EPSLARANJA são glucanas lineares unidas por ligações do tipo β(1®6) e o EPSGRAVIOLA é uma glucana com ligações β(1®3) e com ramificações em C-6 de resíduos glucopiranosídicos. O espectro de FT-IR mostrou uma banda em 891 cm-1, e a espectroscopia de 13C NMR mostrou que todas as ligações eram do tipo β. Estudos realizados com o corante Vermelho Congo indicaram que os EPS possuem conformação em tripla hélice. O EPSLARANJA, uma b- D-(1®6)-glucana, foi submetido a sulfatação visando induzir a atividade anticoagulante e melhorar a solubilidade da molécula em solução, importante para a atividade biológica. Espectros de FT-IR mostraram bandas em 808 and 1252 cm-1, indicando a entrada dos grupos sulfato e as análises de RMN de 13C mostraram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Exopolysaccharides (EPS) as β-glucans are polymers produced by a great variety of microorganisms and can possess different physical and chemical properties, and structural features. These biopolymers having interesting biological activities (antitumor, anti-viral, anticoagulant), and commercial applications in foods, cosmetics and pharmaceutical products. However, for the applications of these macromolecules, it is first necessary to understand their chemical structures. Therefore the goal of that study was the production, chemical characterization and biological activity of four exopolysaccharides (EPSGRAVIOLA, EPSMANGO, EPSPINHA and EPSORANGE) obtained from Botryosphaeria strains isolated from rotting tropical fruit grown on sucrose as carbon and the best EPS was used for the anticoagulant activity The homogeneity of each EPS was determined by gel filtration chromatography, which was eluted as a single peak. Total acid hydrolysis and HPAEC/PAD analysis of each EPS yielded only glucose. Data from methylation analysis and 13C NMR spectroscopy indicated that the EPSMANGO, EPSPINHA and EPSORANGE consisted of a linear chain of (1-6)- linked glucopyranosyl residues and EPSGRAVIOLA consisted of a main chain of glucopyranosyl (1-3) linkages substituted at O-6. FTIR spectra showed one band at 891 cm-1, and 13C NMR spectroscopy showed that all glucosidic linkages were of the β-configuration. Dye-inclusion studies with Congo Red indicated that each EPS existed in a triple-helix conformational state. The EPSORANGE, a β-(1®6)- D-glucan was submitted to a sulfation to induce anticoagulant activity and also to make this EPS more soluble, which is in favor to its biological action. The FT-IR spectrum showed bands at 808 and 1252 cm-1 indicating insertion of sulfonyl groups and the 13C NMR analysis showed that the sulfonyl groups were inserted mainly in C-4 of the b(1®6)-D-glucan... (Complete abstract click electronic access below) / Orientador: Roberto da Silva / Coorientador: Maria de Lourdes Corradi da Silva / Banca: Gabriela Alves Macêdo / Banca: Maria Inês Rezende / Banca: Jonas Contiero / Banca: Eleonora Cano Carmona / Doutor