To see the other types of publications on this topic, follow the link: Tegus.

Dissertations / Theses on the topic 'Tegus'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 31 dissertations / theses for your research on the topic 'Tegus.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Koch, Claudia [Verfasser]. "The Herpetofauna of the Peruvian dry forest along the Andean valley of the Marañón River and its tributaries, with a focus on endemic iguanians, geckos and tegus : Squamata: Iguanidae, Phyllodactylidae, Teiidae / Claudia Koch." Bonn : Universitäts- und Landesbibliothek Bonn, 2014. http://d-nb.info/1048091481/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Sioui, Bruno. "Trajectoires de vie d'adolescents tenus responsables d'agression sexuelle." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24871/24871.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Lönn, Anders, and Tomas Nyberg. "Utbyte mellan Polishögskolan i Umeå och Tegs centralskola." Thesis, Umeå University, Basic training programme for Police Officers, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27271.

Full text
Abstract:

Tegs central skola har tidigare varit en s.k. problemskola, men har numer ett mycket bättre rykte. Vi har fått antydningar om att det finns ett stort intresse från skolan och föräldrarna till eleverna, att polisen ska komma till skolan och informera ungdomarna om t.ex. alkohol/droger och mobbing. Tyvärr har polisen i dagens läge vare sig resurser eller tid att fullt ut tillmötesgå dessa önskemål. Tanken med vårt arbete är att skaffa oss en uppfattning om det är möjligt, och om intresse finns att starta ett förhoppningsvis långvarigt samarbete mellan Tegs central skola och polisutbildningen i Umeå. Vi vill ta reda på vilka problemområden som finns på skolan och i slutändan kunna presentera idéer om hur man tillsammans ska kunna arbeta för att minimera dessa problem. Arbetet kommer att visa på olika faktorer som ligger bakom ungdomars inträde i kriminaliteten, och även idéer om hur ett samarbete mellan skolorna skulle kunna se ut kommer att presenteras

APA, Harvard, Vancouver, ISO, and other styles
4

Hibarino, Denise Akemi. "Pela luz dos olhos meus, pela luz dos olhos teus." reponame:Repositório Institucional da UFPR, 2010. http://hdl.handle.net/1884/24522.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Moirand, Sophie. "Les discours tenus dans la revue "le français dans le monde' : 1961-1981." Besançon, 1987. http://www.theses.fr/1987BESA1009.

Full text
Abstract:
L'objectif principal de la thèse est de mieux comprendre le fonctionnement, la constitution et l'évolution d'un domaine particulier (l'enseignement des langues) au travers de l'analyse des discours qui circulent en son nom dans une revue (créé au début des années 60, à destination des enseignants de français langue étrangère), et dans les rapports que ces textes entretiennent avec les discours des linguistes et d'autres spécialistes des sciences humaines. L'auteur propose une approche empirique qui part de l'observation des régularités formelles rencontrées a la surface des textes et de la mise en relation de différents types d'indices afin de formuler des hypothèses "construites" sur le fonctionnement des variétés discursives ainsi dégagées. Elle s'effectue en trois étapes successives : la première reste à l'intérieur du cadre formel de l'énonciation (Benveniste, Culioli), auquel on intègre le lexique et la syntaxe; la seconde remonte au cadre pragmatique et recherche la forme des macro-actes sous-jacents; la troisième s'interroge sur le projet rhétorique du scripteur (cadre argumentatif). L'auteur en arrive à la conclusion que deux variétés principales semblent fonctionner : un discours apparemment homogène, et prescrivant des savoir-faire, s'organise autour de verbes illustrant les rapports assignes aux acteurs et objets de la classe de langue (une analyse casuelle a été opérée -Fillmore); un discours explicitement hétérogène, et faisant largement place à d'autres, cité ou évoqué des discours tenus ailleurs, mentionne ou invoque des théories, méthodes ou notions, concepts appartenant aux sciences du langage ou à d'autres sciences humaines (une étude de ces intertextualités a été effectuée -Bakhtine). L'hypothèse développée par l'auteur est que l'usage exclusif, conjoint ou alterne de ces deux discours, la manière d'user de ces hétérogénéités montrées permettent de repérer dans un texte, au-delà de son fonctionnement dialogique, les "représentations" qu'un scripteur particulier, a un moment de sa trajectoire professionnelle, parait avoir de la didactique des langues et de son objet.
APA, Harvard, Vancouver, ISO, and other styles
6

Moirand, Sophie. "Les Discours tenus dans la revue "Le Français dans le monde", 1961-1981." Lille 3 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37608079k.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Sanders, Colin E. "Quiescent states of sleep, torpor and hibernation in the." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2331.

Full text
Abstract:
Brazilian tegus (Tupinambis merianae) were instrumented with telemetry encoder implants that measured and broadcast heart rate (HR), breathing rate (fR), and deep body temperature (Tb) and were then allowed to freely roam in outdoor enclosures mimicking their natural environment for a full year (2004) in order to monitor the circadian and circannual patterns in behaviour and cardio-respiratory physiology. The year was divided up into 5 seasons based upon the physiology and behaviour of the tegus: early activity season (Sept.-Nov.), late activity season (Dec.-Feb.), entrance into hibernation (March-April), hibernation (May-July), and arousal from hibernation (August). The activity seasons were characterized by warm weather with frequent rainfall which slowly decreased in temperature and precipitation as tegus started entering hibernation so that the end of the dormant season was marked by dry, cold weather. Tegus in the early activity season demonstrated high activity associated with breeding demands, displayed elevated HR and fR, and were able to maintain a large temperature differential (4-7°C) between deep body temperature (Tb) and their respective burrow (Tburrow) during sleep. As the season progressed into late activity season, average Tb remained constant but average HR and fR progressively declined indicating nightly torpor. Periods of inactivity during the active seasons were rare and associated with inclement weather. Tegus entered hibernation through bouts of inactivity that progressively increased in frequency and duration. During this time, Tb was regulated but declined at different rates in regards to daytime and nighttime values. Heart rate through the entrance into hibernation and hibernation periods frequently demonstrated arrhythmias that increased in duration but decreased with frequency as hibernation progressed. Through hibernation, Tb continued to decline for the first month but HR and fR were constant, demonstrating a temperature independent suppression of metabolism. Through the hibernation season tegus sporadically aroused and emerged from their burrows to warm up and after a short basking period would return to the burrows and swiftly resume hibernation. While hibernating, heart rate was characteristically regular but breathing was sporadic orepisodic. Arousals became more frequent towards the end of hibernation so that when they entered arousal from hibernation season most tegus were emerging daily. At this time daily maximum deep body temperature (Tbmax) swiftly returned to active season values but nighttime daily minimum deep body temperature (Tbmirt) values only showed a gradual increase through August, indicating different body temperature set points (Tbset) for active and sleep states. Changes in heart rate and breathing rate during the year showed greatest correlation with changes in photoperiod, although throughout hibernation HR and fR also showed tight correlation with Tb.
APA, Harvard, Vancouver, ISO, and other styles
8

Bastos, Mariana Cobuci Schmidt. "Sob o signo da paixão: uma leitura de A teus pés, de Ana Cristina Cesar." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/8/8149/tde-13032019-111756/.

Full text
Abstract:
Esta dissertação realiza um percurso interpretativo de A teus pés, único livro de Ana Cristina Cesar publicado por editora, que reúne os três livros lançados por ela de forma independente (Cenas de abril, Correspondência completa e Luvas de pelica), acrescidos de mais um, homônimo. Nesse curso, considerou-se a participação da autora no quadro da poesia marginal dos anos setenta; o aspecto gráfico de seus livros e sua relação com o conteúdo das obras; as reflexões suscitadas por cada livro, e o que possibilitaria sua reunião em um único volume buscando entrever, assim, o projeto poético de Ana Cristina, a sua escrita sob o signo da paixão.
This study traces an interpretative path through A teus pés, the only book that Ana Cristina Cesar released by a publisher, which includes her three self-published books (Cenas de abril, Correspondência completa and Luvas de pelica) plus one, namesake of the group. In this work, were taken into consideration her participation in the Brazilian marginal poetic scene of the seventies; the graphic aspects of her books and its relations to their textual content; the reflections aroused by each book and what could allow their clustering into a single piece of work this way distinguishing Ana Cristinas poetic project, her writing made \"under the sign of passion\".
APA, Harvard, Vancouver, ISO, and other styles
9

Pasquier, Laurent. "Modélisation de raisonnements tenus en contexte : application à la gestion d'incidents sur une ligne de métro." Paris 6, 2002. http://www.theses.fr/2002PA066287.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Gibbons, Theresa. "Engagement, motivation, and performance in a multigenerational organization /." Burnaby B.C. : Simon Fraser University, 2005. http://ir.lib.sfu.ca/handle/1892/3627.

Full text
APA, Harvard, Vancouver, ISO, and other styles
11

Ariyanto, Teguh [Verfasser], and Bastian [Gutachter] Etzold. "Methods for spatial control of pore size and microstructure in porous carbons / Teguh Ariyanto ; Gutachter: Bastian Etzold." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016. http://d-nb.info/1115469037/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
12

Lena, J?nior H?lio de. "A Idade da Revolu??o: Astrojildo Pereira e Jos? Carlos Mari?tegui na constru??o do marxismo." Universidade Federal Rural do Rio de Janeiro, 2007. https://tede.ufrrj.br/jspui/handle/tede/698.

Full text
Abstract:
Made available in DSpace on 2016-04-28T20:13:48Z (GMT). No. of bitstreams: 1 2007 - Helio de Lena Junior.pdf: 2110805 bytes, checksum: d0820b8c6160376aabc7beb93ace93c7 (MD5) Previous issue date: 2007-11-07
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The present thesis has as main interest the comparative study between Astrojildo Pereira and Jos? Carlos Mari?tegui political ideas in the construction of Marxism. We site our analysis from an interpretative focus which approaches the political culture developed by both Latin American Marxists and the role performed by revolutionary intellectuals. Saying that, to analyze the public manifestations from those intellectuals and their respective realities, we were compelled to investigate the relations they had with the classical Marxian ideas. This way, we chose the themes revolutionary journalism, the countrymen class and revolution which collated our propositions to that Marxian tradition. We aim to comprehend the way the characters political ideas were organized and, from the public exposition of those ideas, comprehend how their actions were in their social contexts. We highlight that the comprehension of the political actuation from both actors is extremely important for the consolidation of the proletarians in Latin American political scenario.
A presente tese tem por interesse b?sico o estudo comparado entre as id?ias pol?ticas de Astrojildo Pereira (1890/1965) e Jos? Carlos Mari?tegui (1894/1930) na constru??o do marxismo. Situamos nossas an?lises a partir de um enfoque interpretativo que englobasse a cultura pol?tica desenvolvida pelos dois marxistas latino-americanos e o papel desempenhado pelos intelectuais revolucion?rios. Isto posto, para analisarmos as manifesta??es p?blicas destes intelectuais em suas respectivas realidades, fomos compelidos a investigar as rela??es destes com as id?ias cl?ssicas marxianas. Deste modo, escolhemos os temas jornalismo revolucion?rio, campesinato e revolu??o que cotejassem nossas proposi??es ?quela tradi??o marxiana. Objetivamos entender como se organizaram as id?ias pol?ticas das personagens e, a partir da exposi??o p?blica dessas id?ias, compreender como se deu a atua??o de ambos em seus contextos sociais. Ressaltamos que a compreens?o da atua??o pol?tica dos respectivos atores ? de suma import?ncia para a consolida??o do proletariado no cen?rio pol?tico latino-americano.
APA, Harvard, Vancouver, ISO, and other styles
13

Shadwell, Thomas Slagle Judith Bailey. "Thomas Shadwell's "The Lancashire-witches, and Tegue o Divelly the Irish-priest" : a critical old-spelling edition /." New York : Garland publ, 1991. http://catalogue.bnf.fr/ark:/12148/cb36150389t.

Full text
APA, Harvard, Vancouver, ISO, and other styles
14

KADIB, ELBAN NAVARRO ESTELA. "Typologie stylistique des divers discours tenus sur le probleme des langues au xviiie siecle entre 1750 et 1789." Poitiers, 1994. http://www.theses.fr/1994POIT5025.

Full text
Abstract:
Grace a une methode comparative -qui ne cherche pas l'exhaustivite-, des textes des philosophes-grammariens et des hommes de lettres qui ont ecrit sur le probleme du langage entre 1750 et 1789, un type de discours se degage. Il est caracterise par un lexique precis, analytique, souvent evocateur et marque par l'intensite semantique. Ces lexemes sont agences a l'aide d'une syntaxe descriptive laissant une grande place a la narration a nuance historique. Nous sommes en presence d'un discours engage et expressif ou le souci demonstrativo-argumentatif est dominant, traduisant un desir pressant de persuasion et de communication ainsi qu'une tendance didactique marquee
Thanks to a comparative method -without claiming to be exhaustive-, of texts by philosophers, grammarians and men of letters who have written between 1750 and 1789 on the problems of language, a kind of speech emerges. That of a language characterised by a precise, analytical vocabulary, frequently evocative with a marked semantic intensity. These lexemes are constructed with the help of a descriptive syntax leaving the narrative and historical nuances to play an important role. We discover a committed and lively speech where the major concern is to present a well-argued case. This type of speech display a pressing desire to persuade and communicate as well as a marked didactic tendency
APA, Harvard, Vancouver, ISO, and other styles
15

Ingicco, Thomas. "Les primates quaternaires de Song Terus (Java Est, Indonésie) : implications paléobiogéographiques et archéozoologiques pour l'Asie du Sud-Est." Paris, Muséum national d'histoire naturelle, 2010. http://www.theses.fr/2010MNHN0030.

Full text
Abstract:
Les primates non-humains représentent plus de 70% de la faune holocène du site archéologique en grotte de Song Terus, Java Est (Indonésie). En focalisant notre étude sur ce site, qui présente un remplissage stratigraphique d’une puissance de 15 m recouvrant la limite Pléistocène-Holocène, nous disposons du contexte temporel et spatial où toutes les questions concernant l’interaction homme/primates non-humains peuvent être abordées. Nous commençons cette étude par une présentation générale du contexte, et par la mise en place de référentiels essentiels à notre recherche, mais néanmoins lacunaires jusque là. C’est pourquoi nous décrivons en détail le squelette de l’holotype naturalisé de l’espèce Trachypithecus auratus, jamais décrite du point de vue ostéologique. Nous mettons également en place, plus loin, un système d’estimation des âges au décès des fossiles, basé sur les stades d’usure dentaire. Après une discussion concernant les problèmes existants quant à la place des primates-non humains dans l’actuelle biostratigraphie de Java, nous décrivons en détail les fossiles holocènes de Song Terus. L’espèce T. Auratus représente plus de 96% des restes de primates non-humains, l’espèce Macaca sp. Représentant moins de 4%. Les crânes des fossiles de T. Auratus sont très proches des spécimens actuels, avec toutefois certains caractères partagés avec les individus de Java uniquement, alors que d’autres sont partagés avec les individus de Sumatra et de Bornéo seuls. Nous cherchons à comprendre ceci en étudiant le contour de l’orbite qui nous semble discriminer les fossiles des espèces actuelles. Les descripteurs de Fourier ont été utilisés. Un seul des fossiles les plus récents géologiquement ressemble aux spécimens actuels de T. Auratus, dont la morphologie des individus de Java, de Sumatra et de Bornéo apparaît continue. En revanche, les autres fossiles sortent de la variabilité des spécimens actuels. Nous décidons alors de tester la part de l’endémisme insulaire et des pressions paléoenvironnementales sur ces conformations de l’orbite par une analyse de Two-Block Partial Least Square. Les résultats mettent en évidence une migration unique probablement ancienne du genre Trachypithecus en Asie du Sud-Est insulaire. En revanche, des migrations multiples d’îles en îles ont eu lieu jusqu’à des périodes très récentes, ce qui permet de relativiser l’ouverture de l’environnement sur le plateau de la Sonde durant le dernier maximum glaciaire. Dans la dernière partie de travail, nous cherchons à comprendre la nature de la relation homme/primates non-humains dans le site de Song Terus. L’études des micro-usures dentaires des fossiles de T. Auratus met en évidence une grande consommation de fruits/graines, ce qui est inattendu pour cette espèce hautement folivore, considérée pour des raisons biologiques, parmi la moins flexible des primates. La question d’une relation commensale de ces primates à l’homme est posée. Nous cherchons à l’éclaircir par les méthodes de l’archéozoologie et de l’analyse spatiale. Les résultats obtenus sont complexes et difficiles à interpréter. L’ensemble du squelette est représenté dans le site mis à part les mains. Nous nous sommes interrogé sur les raisons de cette absence, qui pourrait être justifiée par des techniques de piégeage, sans que nous puissions y répondre. L’analyse spatiale ne met évidence aucun traitement particulier des carcasses. Il est probable que la relation homme/primates non-humains au début de l’Holocène ait été multiple, mêlant chasse et parfois apprivoisement comme c’est le cas aujourd’hui chez certains groupes de chasseurs-collecteurs de l’Asie du Sud-Est
Non-human primates represent 70% of the holocene fauna from the archaeological site of Song Terus. On focusing our study on this site, which present a stratigraphical filling of 15 m comprising the Pleistocene-Holocene boundary, we possess the temporal and spatial context where all the questions concerning the interaction between human and non-human primates may be approached. After filling some lacunar datas essential for ou research, we describe in details the fossils of Song Terus. The species Trachypithecus auratus represent up to 96% of the non-human primate remaines, and Macaca sp. Only 4%. We look for distinguishing javan specimens of T. Auratus in one hand and sumatran and bornean specimens in the other hand, as fossils share characters with both of them. We then focus on the contour of the orbites from Elliptical Fourier Analysis as they seem to us, discriminant among actuals and fossils. Two fossils present a completly different shape of the orbite. We test the part of endemism and palaeoenvironment on the shape of the orbites with Two-Block Partial Least Square analysis. Results show a possible very old migration from continent to insular Southeast Asia that occured once. After this period, many migrations occured between the different islands of the region, up to recently. This permit to conclude that probably no savanna corridor existed during the Last Glacial Maximum. To understand the relationship between human and non-human primates, we study dental microwears first. The high frugivory of the T. Auratus fossils from Song Terus is surprising as those species are known to be extremely folivorous and poorly flexible. The question of commensalism of those primates to human is asked. Methods of archaeozoology show different results, as the absence of hand remains, while all the skeleton is completly preserved in the site, could be interpreted as trapping technics. The spatial analysis doesn’t provide any light on any of these hypothesis. We then suspect a complex relationship between human and non-human primates, mixing commensalism and hunting, as it is still known today
APA, Harvard, Vancouver, ISO, and other styles
16

Sacco, Airi Macias. "“Como é a escola dos teus sonhos?” : direitos da criança, educação e inserção ecológica em Angola." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/55413.

Full text
Abstract:
Esta dissertação teve como objetivos conhecer a opinião de crianças angolanas a respeito de suas escolas, investigar como é a escola dos seus sonhos e averiguar como os direitos da criança estão sendo acolhidos nessas instituições. Para tanto foi realizado um estudo que englobou o sistema de ensino público primário do país, representado por 15 escolas localizadas em cinco províncias angolanas. As crianças participaram de entrevistas em grupo e o método utilizado foi a inserção ecológica. A análise dos dados foi realizada com base na Teoria Bioecológica do Desenvolvimento Humano e os resultados indicaram que as interações de crianças, professores, diretores e escolas são caracterizadas por desequilíbrio de poder e autoritarismo e, por isso, carecem de reciprocidade. A escola dos sonhos das crianças é um local com condições mínimas de infraestrutura, no qual se sentem acolhidas e respeitadas. A promoção e o respeito aos direitos da criança ainda são incipientes em Angola de maneira geral e nas escolas em particular.
This dissertation aimed to know the opinion of Angolan children with respect to their schools, investigate how the school of their dreams is and to verify how children’s rights are received in those institutions. This study encompassed Angola’s public primary education system, represented by 15 schools located in five Angolan provinces. The children participated in group interviews and the method used during data collection was the ecological engagement. Data analysis was done through the Bioecological Theory of Human Development and the results indicate that the interaction among children, teachers, directors and schools are characterized by the imbalance of power and authoritarianism, reason why the relationship lacks reciprocity. Children’s dream school is a place with minimal infrastructure where they feel welcomed and respected. In general, the promotion and respect to children’s rights are still incipient in Angola, especially in schools.
APA, Harvard, Vancouver, ISO, and other styles
17

Aribit, Frédéric. "André Breton, Georges Bataille : à l'impossible tenus... : essai d'une confrontation interprétative des romans familiaux jusqu'à la seconde guerre mondiale." Pau, 2006. http://www.theses.fr/2006PAUU1005.

Full text
Abstract:
Ce travail s’est donné pour objectif de reprendre la confrontation entre André Breton et Georges Bataille en postulant entre eux un mode original d’échange dont l’interlocution directe n’est qu’une des modalités, et en tentant d’en éclairer les enjeux dans les champs du savoir successivement concernés. Sa démarche, diachronique, part des romans familiaux et s’achève au début de la Seconde guerre mondiale, après qu’un élan communautaire de part et d’autre s’est effondré, ouvrant une phase totalement différente de ce même échange. Il traverse ainsi une large période de l’histoire de cette confrontation, qui passe notamment par les conditions de leur rencontre, la réception de la psychanalyse, l’évolution de leurs positionnements philosophiques ou leur inscription idéologique en marge de la gauche révolutionnaire. Cette approche générale aide à repenser notamment deux moments particulièrement critiques du débat, en l’occurrence l’apogée violent de leur désaccord de 1929-1930, et la tentative de rapprochement de 1935, sur la base d’une réactivation politique du mythe. Plus généralement, il invite à poser la question du rapport au langage et à la poésie, et questionne l’incitation à écrire en proposant également une incursion croisée dans les principales œuvres narratives de l’époque. Un tel travail, on le voit, excède lui-même la « chose littéraire » au sens strict, ou plutôt replace celle-ci au confluent d’un ensemble de domaines connexes des sciences humaines (philosophie, politique, psychanalyse, arts…), précisément là où s’ancre la réflexion globale sur l’homme que chacun des deux aura voulu mener
The aim that has been given to this work is to start one more time the comparison between André Breton and Georges Bataille, starting from the premise of an original way of communication whose direct dialogue is but one of the forms, and trying to clarify its issues in the successively concerned fields of knowledge. Its –diachronic- reasoning starts from the family novels and ends at the beginning of World War II, after a community fervour on each side collapsed, opening a completely different period of the same exchange. It thus goes through a wide period of the history of that comparison, which, among others, deals with the conditions in which they met, how they met with psychoanalysis, the way their philosophical positioning or their ideological inscription on the fringe of the revolutionary left developed. This general approach helps think again about, among others, two especially crucial moments of the discussion, i. E. The violent climax of their 1929-1930 disagreement, and their 1935 attempt to get closer again, on the basis of a political reactivation of the myth. More generally, it invites to ask the question of the relationship to language and poetry, and questions about the incentive to write, suggesting at the same time a crossed foray into the major narrative works of the time. Such a work, as it seems, goes beyond the “literary thing” in the strict sense of the term, or rather takes its place at the meeting point of a set of topics related to the social sciences (philosophy, politics, psychoanalysis, art…), precisely where the global thought about man that each of them will have decided to lead is fixed
APA, Harvard, Vancouver, ISO, and other styles
18

Silveira, Lilian Cristina da. "Reorganização estrutural e metabólica do tecido cardíaco associada à dormência e jejum sazonal em lagartos teiú Tupinambis merianae." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-13052011-100148/.

Full text
Abstract:
O coração é um órgão notável por sua flexibilidade estrutural e metabólica em resposta a variações de demanda. Na dormência sazonal, a interrupção da alimentação, associada à inatividade física e à acentuada redução da frequência cardíaca, ocasiona uma inibição da demanda sobre a função do órgão e, provavelmente, uma reorganização estrutural e metabólica do tecido cardíaco. Estes aspectos foram investigados ao longo do ciclo anual de atividades em lagartos teiú Tupinambis merianae, com o objetivo de examinar as alterações de capacidade funcional cardíaca dadas por ajustes da massa, estrutura e composição do tecido, por regulação do fluxo de substratos energéticos em vias de produção de energia e por mudanças da composição de ácidos graxos dos fosfolipídios das membranas. Grupos de animais jovens foram mortos em diferentes fases do primeiro ciclo anual e após 20 dias de jejum na fase ativa e o ventrículo cardíaco foi removido e pesado. Um fragmento da parede ventricular foi retirado, transferido para fixador e utilizado posteriormente para a confecção de cortes histológicos de 10 μm de espessura que foram analisados utilizando-se método estereológico. O restante do tecido ventricular foi congelado em N2 líquido e conservado em freezer -80 ºC. Os teores de água, proteína total e solúvel e lipídio total foram medidos por meio de ensaios padrão; as atividades máximas de enzimas foram medidas por espectrofotometria em condições saturantes de substratos e cofatores; e o perfil de ácidos graxos dos lipídios neutros e polares foi determinado por cromatografia gasosa. No início do outono, a massa ventricular relativa é 0,16% e aumenta 31% até o final desta fase, quando o miocárdio esponjoso possui aspecto denso e poucos espaços lacunares que ocupam cerca de 8% da área total do corte. Este arranjo é mantido na dormência, quando a massa ventricular relativa aumenta 29% em relação ao final do outono, e no início do despertar, quando a massa ventricular relativa diminui para valores semelhantes aos do final do outono. Após a retomada da alimentação, a massa ventricular relativa volta a exibir uma porcentagem comparável a da dormência, juntamente com um pequeno aumento da área de lacunas no miocárdio esponjoso. Na primavera, a massa ventricular relativa é de 0,24% e o miocárdio esponjoso possui aspecto extremamente reticulado, com 29% da área total do corte ocupada por espaços lacunares. Animais ativos submetidos a jejum apresentam redução de 19% da massa ventricular relativa em relação a animais alimentados. A densidade numérica de cardiomiócitos na camada esponjosa é 37% menor na dormência em relação à atividade de primavera, resultando em um volume calculado de um cardiomiócito nesta fase 52% maior em relação à atividade de primavera. A análise do teor de água, proteínas totais e solúveis não indica variação ao longo do ciclo anual, com exceção de uma tendência ao aumento do teor de água na dormência e de uma tendência à redução do teor de proteínas solúveis após o despertar e ingestão de água e no grupo de animais ativos submetidos ao jejum. Na atividade de outono e dormência de inverno a concentração de proteínas miofibrilares é reduzida em relação à atividade de primavera e aumenta no início do despertar após a ingestão de água. A concentração de lipídios totais é menor na dormência e despertar em relação à atividade de outono e no grupo de animais submetidos a jejum em relação a animais alimentados. As enzimas glicolíticas PK e LDH não variam ao longo do ciclo anual, enquanto a CS, indicadora da capacidade aeróbia, exibe forte tendência ao aumento na dormência, e a HOAD, enzima da β-oxidação lipídica, encontra-se inibida na dormência e no despertar em relação ao outono. Em contraste, com exceção da LDH que também não varia, a PK e a CS diminuem, enquanto que a HOAD é mantida constante após jejum na fase ativa. As variações do perfil de ácidos graxos da fração lipídica neutra sugerem que ácidos graxos insaturados são preferencialmente mobilizados das reservas do miocárdio durante a dormência e início do despertar, enquanto que no jejum durante a fase ativa as diferentes classes de ácidos graxos são equitativamente mobilizadas. A composição de ácidos graxos da fração lipídica polar exibe uma notável constância ao longo do ciclo anual, sugerindo que os ajustes à dormência sazonal não afetam de modo abrangente os fosfolipídios do tecido cardíaco e, portanto, não sugerem um papel preponderante de mudanças da composição lipídica das membranas na regulação metabólica sazonal nos teiús. Além disso, o contraste em relação às alterações observadas em mamíferos hibernantes sugere que, nestes, os ajustes seriam mais relacionados com a adaptação às baixas temperaturas corpóreas típicas da hibernação. A análise de regressão indica uma variação do conteúdo dos ácidos graxos C18:1n-9, C22:5n-6 e C22:6n-3 em função da massa corpórea dos jovens teiús e as mudanças do padrão alométrico sugerem uma relação entre o conteúdo destes ácidos graxos e as diferenças de taxa metabólica em animais de diferentes massas corpóreas, observadas em determinadas fases do ciclo anual de atividades e após o jejum durante a fase ativa.
The structural and metabolic flexibility of cardiac response to a variable physiological demand is notable. During seasonal dormancy, interruption of feeding together with inactivity and reduced heart beating, cause a large decrease of demand which probably brings about structural and metabolic heart tissue reorganization. These aspects were studied during the annual cycle in young tegu lizards Tupinambis merianae to investigate the hypothesis of seasonal changes of the heart capacities given by adjustments of tissue mass, structure and composition, by regulation of flux of substrates in the pathways of energy production, and by changes in the composition of fatty acids of tissue membranes. Groups of animals were killed in selected phases during the first year cycle of young tegus and after a 20 days fasting period during spring activity. Heart ventricle was removed and weighed and a tissue sample was collected and transfered to fixative solution, being used to obtain tissue slices of 10μm width for histological analysis with stereological tools. The remaining tissue was cut and split into aliquots, frozen in liquid N2 and stored at -80ºC. Later, the aliquots were used to assess the content of water, total and soluble proteins, and total lipids, by standard assays, the maximum activity of enzymes by spectrophotometry, and neutral and polar fatty acids profiles by gas chromatography. In early fall, the relative mass ventricle is 0.16%, and 31% increased in late fall, when the spongy myocardium appears dense and with few lacunar spaces which area corresponds to 8% of slice total área. During dormancy, the ventricle mass increases further 29%, decreasing to values of late fall during early arousal. After food intake, mass ventricle is again increased together with a small increase of the lacunar spaces, which appear highly expanded later in spring (29% of the total area), when tissue mass is 0,24% increased in relation to early fall. Unlike dormancy, fasting during spring caused a decrease of 19% of the ventricle mass. The cardiomyocytes density in the spongy layer is 37% decreased during dormancy while estimated cell volume is 52% increased, in relation to spring activity. There was no seasonal changes in the content of water and proteins in the groups analysed, except to a tendency to increase in the water content during dormancy, and to decrease in the soluble proteins in early arousal and in fasted animals. Myofibrillar protein is lower during fall and dormancy in relation to spring, increasing soon in early arousal after water intake. Total lipids decrease in the tissue during dormancy in relation to late fall by similar proportion than after fasting during spring. The glycolytic enzymes PK e LDH are unchanged during the year cycle, whereas the mitochondrial CS shows a tendency to increase, and HOAD, a β-oxidation enzyme, is decreased during dormancy and early arousal, in relation to fall. Unlike, PK and CS are decreased, while HOAD is unchanged after a period of fasting during spring. Fatty acids (FA) profiles of neutral lipids suggest that unsaturated FA are preferentially mobilized during dormancy and arousal, whereas all FA would be equally used during spring fasting. FA of polar lipids are remarkably constant during the year, suggesting that membrane FA in the heart tissue are not generally affected by season, and thus, results do not support a predominant role played by compositional changes of membranes in metabolic depression in the tegu. In addition, the otherwise distinct findings with hibernating mammals suggest that changes of FA composition in these animals would be an adaptation to the low body temperature of torpor, rather than mechanism of metabolic inhibition. Regression analysis indicate significant relationships of C18:1n-9, C22:5n-6, and C22:6n-3 contents as a function of body mass in young tegus, and changes in the allometric patterns are consistent with a putative relationship between these FA levels and the scaling of mass specific metabolic rates of young tegus during the year cycle.
APA, Harvard, Vancouver, ISO, and other styles
19

Wright, Kathryn M. "Loading mechanics in femora of tiger salamanders (Ambystoma tigrinum) and tegu lizards (Tupinambis merianae) implications for the evolution of limb bone design /." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1220474405/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
20

Hameau, Sébastien. "Datation des sites paléolithiques du Pléistocène moyen et supérieur de Punung (Pacitan, Java) : Applications des méthodes ESR et U-Th aux grottes de Song Terus et Goa Tabuhan." Paris, Muséum national d'histoire naturelle, 2004. http://www.theses.fr/2004MNHN0027.

Full text
Abstract:
Deux grottes, Goa Tabuhan et Song Terus, près de Pacitan (Java, Indonésie) riches en matériel archéologique et paléontologique en place ont été étudiées. Des datations par U-Th et RPE, liées à une étude du remplissage, ont permis de définir un cadre chronologique. Les industries "Terus" sont les plus anciennes de la grotte de Song Terus et sont datées d'environ 300 ka. Les niveaux archéologiques "Tabuhan" ont été datés entre 30 et 80 ka. Lors des calculs d'âges RPE, l'environnement sédimentaire de l'échantillon a été modélisé afin de déterminer la dose externe. Les niveaux "Keplek" marqués par la présence d'Homo sapiens sont holocènes. Enfin, la datation d'un spéléothème a mis en évidence un dépôt des remplissages karstiques dès le Pléistocène Moyen. L'ensemble de ces résultats montre la possibilité de trouver, dans cette région, des niveaux correspondant à la période de transition entre Homo erectus et Homo sapiens
Two caves in Pacitan area (Java,Indonesia), Goa Tabuhan and Song Terus, rich in archaeological and palaeontological material have been studied. The application of U-series and ESR methods, combined with a study of the sedimentary filling, allows us to define a chronological framework for the geological and archaeological levels. The "Terus" lithic industry are the oldest of the Song Terus cave and are dated to 300 ky. The "Tabuhan" archaeological levels are dated from 30 to 80 ky. To apply ESR method, it was necessary to modelize the sedimentary surrounding of the sample in order evaluate the external dose rate. The "Keplek" levels which contain many artefacts associated with an human burial are Holocene aged. Finally, the dating of a stalagmitic flowstone, provide evidence of Middle Pleistocene age for the karstic fillings (more than 300 ky). These results obtained indicate the possibility in this area of finding levels corresponding to the Homo erectus-Homo sapiens transition
APA, Harvard, Vancouver, ISO, and other styles
21

Haddad, Laura Saade. "O papel dos lipídios na reorganização metabólica associada à dormência sazonal no lagarto teiú Tupinambis merianae (Sauria, Teidae)." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-13022008-170743/.

Full text
Abstract:
O jejum prolongado associado `a dormência sazonal é um fenômeno característico de diversos grupos de vertebrados, e os lipídios tem se mostrado bastante importantes na manutenção destes animais. No presente estudo pretendeu-se caracterizar a reorganização metabólica no jejum de 3-4 meses associado à dormência e depressão metabólica acentuada em lagartos teiú no primeiro ciclo anual de atividades, elucidando (1) qual o papel do metabolismo lipídico e de outros substratos energéticos na regulação da massa corpórea e da taxa metabólica dos teiús jovens ao longo do primeiro ciclo anual (2) qual é o comportamento de enzimas do metabolismo energético de diferentes substratos ao longo do ciclo sazonal, relacionadas à manutenção dos teiús durante o jejum hipometabólico e no retorno a atividade. (3) qual é perfil dos ácidos graxos do plasma e diferentes tecidos ao longo do ciclo sazonal e (4) testar se as predições da teoria da membrana como marca-passo do metabolismo se aplicam a um modelo intra-específico e sazonal, de forma a explicar a regulação da acentuada depressão metabólica nos lagartos teiú Para tal, foram determinadas as atividades de enzimas das vias do metabolismo energético de carboidratos (PECK), lipídios (CPT I e CPT II) e proteínas (GOT), e foi determinada a composição lipídica do plasma e dos tecidos de reserva como os corpos gordurosos abdominais e fígado, assim como a composição de membrana do tecido hepático total e das mitocôndrias e do músculo esquelético da pata PIT na atividade de outono, dormência de inverno, despertar, animais ativos na primavera e submetidos a um jejum forçado. Os resultados em conjunto parecem indicar que embora as vias oxidativas estejam reduzidas no tecido hepático, o potencial de mobilização e oxidação de lipídios está aumentado no jejum natural, evidenciando a importância deste substrato na manutenção dos lagartos teiú, e que haveria uma mobilização seletiva de ácidos graxos enquanto outros são mantidos nos tecidos. Adicionalmente, as respostas na composição dos tecidos ao jejum forçado parecem ser diferentes em relação ao jejum natural. O presente trabalho é pioneiro a fazer uma descrição minuciosa da composição lipídica de tecidos e membranas, e o primeiro a fazer uma análise da aplicação da teoria das membranas como 90 marcapasso do metabolismo em uma comparação intra-específica em um vertebrado que exibe dormência sazonal. Esta teoria parece não se aplicar a este modelo, de forma que a regulação do metabolismo parece ser por mecanismos que não uma alteração na composição de membrana dos tecidos.
Seasonal dormancy is a widespread phenomenon among vertebrates, in which lipid stores in the body tissues constitute the major energy source during the prolonged fasting. In addition, there are recent evidence indicating a role played by the lipid metabolism and the fatty acids derived in the regulation of membrane functions, resulting in modulation of whole body metabolic rates in the organisms, as well as integrating nutritional and hormonal signals that promote metabolic responses to changes in fuel availability. The present study investigates the metabolic reorganization and lipidic and fatty acid composition in tissues and subcellular fractions from tegu lizards (Tupinambis merianae), associated with metabolic depression and fasting during seasonal dormancy. Maximum enzyme activities related to the catabolism of carbohydrates (PEPCK), lipids (CPT I, II), and proteins (GOT) in liver were estimated by spectrophotometry and radiochemical assay, the Na+K+ATPase activity was assayed in the liver by standard enzymatic methods, and the lipid and fatty acid composition were analysed in the abdominal fat bodies, plasma, skeletal muscle, and in liver whole tissue and mitochondrial fractions, using gas chromatography, during autumn activity, winter dormancy, arousal, spring activity, and in animals deprived of food for 20 days during activity. During the hypometabolic state, it was found: (1) a significant decrease in the aerobic capacity and gradual increase in the potential for oxidation of long-chain fatty acids in the mitochondria of liver tissue; (2) differential lipid and fatty acid composition in the fat bodies compared to the profiles obtained with plasma, muscle and liver tissue, suggesting selective mobilization of fatty acids; (3) no significant changes in the Na+K+ATPase activity in liver and significant changes in the total and individual fractions of MUFA and PUFA as a function of the seasonal cycle, in the opposite direction indicated by the theory of membranes as pacemakers of metabolism, suggesting however, an important role played by MUFA in the metabolic reorganization during seasonal dormancy.
APA, Harvard, Vancouver, ISO, and other styles
22

Tucker, Derek B. "Molecular Studies of South American Teiid Lizards (Teiidae: Squamata) from Deep Time to Shallow Divergences." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6419.

Full text
Abstract:
I focus on phylogenetic relationships of teiid lizards beginning with generic and species relationship within the family, followed by a detailed biogeographical examination of the Caribbean genus Pholidoscelis, and end by studying species boundaries and phylogeographic patterns of the widespread Giant Ameiva Ameiva ameiva. Genomic data (488,656 bp of aligned nuclear DNA) recovered a well-supported phylogeny for Teiidae, showing monophyly for 18 genera including those recently described using morphology and smaller molecular datasets. All three methods of phylogenetic estimation (two species tree, one concatenation) recovered identical topologies except for some relationships within the subfamily Tupinambinae (i.e. position of Salvator and Dracaena) and species relationships within Pholidoscelis, but these were unsupported in all analyses. Phylogenetic reconstruction focused on Caribbean Pholidoscelis recovered novel relationships not reported in previous studies that were based on significantly smaller datasets. Using fossil data, I improve upon divergence time estimates and hypotheses for the biogeographic history of the genus. It is proposed that Pholidoscelis colonized the Caribbean islands through the Lesser Antilles based on biogeographic analysis, the directionality of ocean currents, and evidence that most Caribbean taxa originally colonized from South America. Genetic relationships among populations within the Ameiva ameiva species complex have been poorly understood as a result of its continental-scale distribution and an absence of molecular data for the group. Mitochondrial ND2 data for 357 samples from 233 localities show that A. ameiva may consist of up to six species, with pairwise genetic distances among these six groups ranging from 4.7–12.8%. An examination of morphological characters supports the molecular findings with prediction accuracy of the six clades reaching 72.5% using the seven most diagnostic predictors.
APA, Harvard, Vancouver, ISO, and other styles
23

Silveira, Lilian Cristina da. "Variação sazonal do metabolismo energético no primeiro ciclo anual de lagartos teiú Tupinambis merianae: correlatos com atividades diárias, adiposidade e proteção antioxidante." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-06042016-091433/.

Full text
Abstract:
Lagartos teiú eclodem no verão e enfrentam o desafio de crescer e armazenar substratos em um curto período de tempo, antes do início do período de jejum e depressão metabólica (≈80%) a temperaturas amenas durante o inverno (≈17 °C). No despertar, o aumento do metabolismo e a reperfusão de órgãos favoreceriam a ocorrência de estresse oxidativo. Na primeira parte do presente estudo investigou−se os ajustes que compatibilizam as demandas em teiús neonatos, especialmente na pré-hibernação, por meio da gravação do comportamento em vídeo e da análise da massa dos corpos gordurosos abdominais e do nível plasmático de corticosterona (CORT) durante o primeiro ciclo anual. No início do outono a massa corpórea dos teiús foi 27 g e o comprimento rostro−cloacal 9,3 cm e aumentaram 40% e 20%, respectivamente, ao longo do outono, enquanto que as taxas diminuíram progressivamente até atingirem o valor zero no início do inverno. Na primavera, a massa corpórea dos teiús aumentou 80% em relação ao despertar e dobrou em relação ao final do verão; o comprimento acumulou um aumento de 27% em relação ao final do verão. A massa relativa dos corpos gordurosos foi 3,7% no início do outono e diminuiu nos meses subsequentes; no despertar, este estoque acumulou uma perda de 63% da sua massa. No início do outono 74% dos teiús estavam ativos por 4,7 h e permaneceram 2 h assoalhando diariamente; ao longo do outono o número de animais ativos e o tempo em atividade diminuíram até que todos se tornaram inativos. Na primavera 83% dos teiús estavam ativos por 7 h e permaneceram 4 h assoalhando. Um padrão sazonal similar foi observado na atividade locomotora e na alimentação. No outono, a alimentação cessou antes da atividade diária e os teiús tornaram−se afágicos algumas semanas antes da entrada em hibernação. Os maiores níveis de CORT foram observados no início do outono, reduzindo progressivamente até valores 75 e 86% menores na dormência e despertar, respectivamente; na primavera os níveis de CORT foram 32% menores em comparação com o início do outono. Este padrão sugere um papel da CORT nos ajustes que promovem a ingestão de alimento e a deposição de substratos energéticos no outono. A redução da atividade geral no final do outono contribuiria para a economia energética e manutenção da massa corpórea, apesar da redução da ingestão de alimento. O curso temporal das alterações fisiológicas e comportamentais em neonatos reforça a ideia de que a dormência sazonal nos teiús é o resultado da expressão de um ritmo endógeno. Na segunda parte do estudo foi investigada a hipótese de que ocorreriam ajustes das defesas antioxidantes durante a hibernação, em antecipação ao despertar. Foram analisados marcadores de estresse oxidativo e antioxidantes em vários órgãos de teiús em diferentes fases do primeiro ciclo anual. A CS, um indicador do potencial oxidante, não variou no fígado e foi menor no rim e no pulmão na hibernação. As enzimas antioxidantes revelaram (1) um efeito abrangente de redução das taxas na hibernação e despertar; por exemplo, GR e CAT foram menores em todos órgãos analisados e a GST tendeu a diminuir no fígado e no rim, embora constante no coração e no pulmão. A G6PDH no fígado e no rim não variou. (2) No fígado, a GST, a Se−GPX e o teor de TBARS foram maiores na atividade de outono em relação à primavera e a Se−GPX permaneceu elevada na hibernação. (3) No fígado, a SOD foi maior na hibernação e despertar em relação ao outono e a Mn−SOD seguiu este padrão. Em contraste, no rim, coração e pulmão a SOD foi menor na hibernação e as taxas se recuperaram no coração e pulmão no despertar. A Mn−SOD seguiu este padrão no pulmão. A concentração e o estado redox da glutationa não variaram no fígado, rim e coração; no pulmão o teor de Eq−GSH e GSH foi menor na hibernação, com tendência à recuperação no despertar. O teor de PC no rim foi maior na hibernação e diminuiu no despertar. No fígado, as alterações no jejum se assemelham às sazonais, como sugerem a inibição da CAT e GR e aumento da Se−GPX. Os efeitos do jejum na primavera no rim diferem dos efeitos sazonais, como sugerem a redução do teor de Eq−GSH e GSH e o aumento da razão GSSG:GSH, a redução da G6PDH e o aumento de PC. No conjunto, houve um efeito predominante de redução das taxas enzimáticas na hibernação e no despertar, exceto pelas taxas aumentadas da SOD e Se−GPX no fígado e pela recuperação da SOD no coração e da GR, SOD e Mn−SOD no pulmão no despertar. As elevadas taxas das enzimas antioxidantes no teiú em comparação a outros ectotermos e a ausência de evidências de estresse oxidativo no despertar sugerem que a atividade enzimática remanescente é suficiente para prevenir danos aos tecidos face às flutuações do metabolismo
The tegu lizards hatch during the summer, when they face the challenge of growing and storing substrates during a short time before going into fasting and metabolic depression (≈80% at 17 °C) during winter. The reactivation of metabolism and of blood perfusion during arousal could favor the occurrence of oxidative stress in the tissues. The first part of his study investigated adjustments which potentially conciliate energy demands in neonatal tegus, particularly during pre-hibernation, by video recording of animal behavior and by measuring the mass of fat bodies and levels of plasma corticosterone (CORT) during the annual cycle. In the early autumn the body mass of the tegu was 27 g and the rostro−cloacal length was 9.3 cm, which increased 40% and 20%, respectively, while the rates decreased progressively until reach zero in winter. In spring activity body mass increased 80% in relation to values during arousal and duplicated in relation to late summer. The fat bodies mass relative to body mass was 3.7% in early autumn, and decreased during the subsequent months accumulating a mass loss of 63% during arousal. In early autumn, 74% of the tegus were active for 4.7 h and they basked for 2 h daily; during the autumn the number of animals and the time spent in activity decreased until they become totally inactive. In spring 83% of the tegus were active for 7 h and they basked for 4 h daily. Similar seasonal pattern was observed in the locomotory and feeding activities. In the autumn, feeding was interrupted prior to the interruption of daily activity and the tegus were aphagic a few weeks before the entry into hibernation. The CORT level was the highest in early autumn and reduced progressively to 75% and 86% during winter and arousal in early spring, respectively; later during spring the levels were 32% lower than the autumn levels. These changes suggest a role of CORT in the adjustments which promote food intake and substrate storage during the autumn. Despite a reduced food intake, the widespread decrease of daily activities in late autumn would contribute to energy saving and body mass maintenance. The time course of physiological and behavioral changes in neonates reinforces the idea of an endogenous rhythm underlying seasonal dormancy in the tegu. The second part of this study investigated the hypothesis of adjustments in antioxidant system preparatory to the moment of arousal by the analysis of markers of oxidative stress and of antioxidants in several organs of neonatal tegus, during different phases of the annual cycle and during starvation in the spring. The Vmax of CS, an indicator of the oxidative potential, did not vary in the liver and was smaller in the kidney and lung of dormant tegus. The antioxidant enzymes revealed (1) a widespread effect of lowering rates during dormancy and arousal; for instance, GR and CAT were lower in all organs examined and GST had a tendency to be lower in the liver and in the kidney tissues, although it was constant in the heart and in the lung. (2) In the liver, GST and Se-GPX, and the levels of TBARs were higher in the autumn than in the spring activity. (3) In the liver, SOD was higher during dormancy and arousal in relation to the autumn, and Mn−SOD followed this pattern. Contrastingly, SOD in the kidney, heart and lung was lower during dormancy, and rates recovered in the heart and lung during arousal before food intake. The Mn-SOD followed this pattern in the lung. The glutathione concentration and the redox balance did not change in the liver, kidney and heart; in the lung, the levels of Eq−GSH and GSH were lower and had a tendency to increase during arousal. Importantly, carbonyl proteins were increased in the kidney during dormancy and recovered during arousal. The effects of starvation during spring differed of those of fasting during winter in the kidney, as shown by the lower Eq−GSH levels and increased GSSG:GSH ratio, the lower G6PDH, and the increased carbonyl proteins. In the liver, changes during starvation followed seasonal patterns, as shown by increased Se-GPX, and decreased CAT and GR, together indicating a consistent effect exerted by interruption of food intake. The high rates of antioxidant enzymes in neonatal tegus compared with other ectotherms, and the absence of evidence of oxidative stress at arousal suggest that remaining enzyme activities are sufficient to prevent tissue damage that could be caused by the metabolic fluctuations during the annual cycle in the tegu
APA, Harvard, Vancouver, ISO, and other styles
24

Oulfarsi, Mostafa. "Contribution à l’amélioration de la fiabilité de modules thermoélectriques : développement de solutions matériaux alternatives." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0228.

Full text
Abstract:
La conversion d’énergie à partir de la chaleur perdue par effets thermoélectriques (effet Seebeck) est une nouvelle source d’énergie renouvelable potentielle. La technologie thermoélectrique (TE) est néanmoins limitée à des applications terrestres de niche du fait de son faible rendement (5-6 %), mais aussi à cause des défis technologiques à surmonter pour éviter une dégradation des générateurs TE (GTE) employés. Notre thèse s’inscrit dans cette problématique dans le cadre d'un programme de recherche soutenu par l’ANR (projet RELIATEG) incluant comme partenaires la société HotBlockOnBoard (HBOB), le CEA LITEN, le CIRIMAT et l'IJL. L'objectif est de fiabiliser les GTE à base de siliciures, Mg₂Si₁₋ₓSnₓ pour le type n et de MnSi₁₊ᵧ pour le type p, fabriqués par HBOB pour une utilisation à long terme au voisinage de 400-500°C. Notre rôle consiste principalement à comprendre les mécanismes conduisant à leur fragilisation, notamment en ce qui concerne les problèmes d'oxydation du matériau Mg₂Si₀,₆Sn₀,₄. Ceux-ci étant inévitables, nous nous sommes tournés vers la solution de trouver un revêtement protecteur et de tester la stabilité thermique sous air d’un matériau Mg₂Si₁₋ₓSnₓ, moins sensible. Après avoir établi une synthèse bibliographique traitant des notions de base de la TE, de l'état de l’art des matériaux TE et justifié le choix des matériaux utilisés par HBOB, nous présentons les diverses étapes de la fabrication des GTE et les techniques expérimentales utilisées pour caractériser la microstructure des matériaux TE et leur stabilité thermique. Les tests de performance réalisés sur des GTE à quatre jambes montrent que la puissance obtenue, mesurée jusqu'à 450°C, est reproductible pour les 25 modules testés. Elle est toutefois environ 25 % plus faible que celle que l'on pourrait atteindre avec un GTE parfait, comme le montre les simulations que nous avons réalisées à l'aide du logiciel Comsol MultiPhysics. Les tests de stabilité ont montré que les modules sont stables sous air à 250°C, durant 500 h ou sous 1000 cycles, et qu'ils commencent à se dégrader sous air dès 350°C par le biais d'un phénomène de peste lié à l'oxydation du matériau TE Mg₂Si₀,₆Sn₀,₄ du côté chaud du GTE. Sous vide, ce processus est ralenti mais la présence d'oxygène résiduel ne permet pas de totalement stabiliser le matériau. A 500°C sous air, la peste est observée dès 3 heures de test. Les tests d'oxydation menés sur les deux matériaux à teneur en Sn différente ont permis de montrer le rôle déterminant de l'étain sur les phénomènes d'oxydation. Un modèle expliquant le phénomène de peste a pu être développé grâce à l'analyse combinée des résultats obtenus par des mesures thermogravimétriques, microscopie électronique à balayage et diffraction des rayons X. En nous appuyant sur la bibliographie et sur les diagrammes de phases des différents systèmes, des revêtements protecteurs céramiques, siliciures métalliques, métaux et verres ont été étudiés. Plusieurs voies de dépôt ont été explorées : frittage par Spark Plasma Sintering, nickelage électrochimique, pack cémentation, dépôts par pulvérisation (slurry, PVD et spray). Les revêtements les plus prometteurs ont été obtenus avec un verre dont le CET est proche de celui du matériau de type n
Energy conversion from waste heat through thermoelectric effects (Seebeck effect) is a potential new renewable energy source. The thermoelectric (TE) technology is nevertheless limited to niche terrestrial applications due to its low efficiency (5-6%), but also due to the technological challenges to be overcome to avoid a degradation of the TE generators (TEG). Our thesis is devoted to this problem within the framework of a research program supported by the ANR (RELIATEG project) including HotBlockOnBoard (HBOB), CEA LITEN, CIRIMAT and IJL as partners. The objective is to make reliable the TEG, manufactured by HBOB, based on silicides, Mg₂Si₁₋ₓSnₓ (n-type) and MnSi₁₊ᵧ (p-type), for long-term use in the vicinity of 400-500°C. Our main role is to understand the mechanisms leading to their embrittlement, particularly to the oxidation problems linked to the Mg₂Si₀,₆Sn₀,₄ material. As they are unavoidable, we turned to the solutions of finding a protective coating and/or testing the thermal stability under air of a Mg₂Si₁₋ₓSnₓ material, less sensitive to oxidation. After a bibliographical synthesis of the basic concepts of TE and of the state of the art of TE materials, the choice of materials used by HBOB have been justified. The various stages of TEG manufacturing and the experimental techniques used to characterize the microstructure of TE materials and their thermal stability are presented. The performance tests performed on TEGs show that the power obtained, measured up to 450°C, is reproducible for the 25 devices tested. However, it is about 25% lower than what one could achieve with a perfect TEG, as shown by the simulations we carried out using the Comsol MultiPhysics software. The stability tests showed that the devices are stable under air at 250°C, for 500 hours or under 1000 cycles, and that they begin to degrade under air at 350°C through a pesting phenomenon linked to the oxidation of Mg₂Si₀,₆Sn₀,₄. Under vacuum, this process is slowed down but the presence of residual oxygen does not completely stabilize the material. At 500°C under air, the pesting is observed from 3 hours of testing. The oxidation tests carried out on the two materials with different Sn content showed the significant role of tin on the oxidation phenomena. A model explaining the pesting phenomenon was developed by the combined analyses of results obtained by thermogravimetric measurements, scanning electron microscopy and X-ray diffraction. On the basis of bibliography and phase diagrams of the differents systems, protective coatings based on ceramics, metallic silicides, metals and glasses have been studied. Several deposition methods were explored: sintering by Spark Plasma Sintering, electrochemical nickel plating, pack cementation, slurry, PVD and spray deposits. The most promising coatings were obtained with a glass whose CTE is close to that of the n-type material
APA, Harvard, Vancouver, ISO, and other styles
25

Souza, Carlos Eduardo Siqueira Ferreira de. "A lírica fragmentária de Ana Cristina Cesar: autobiografismo e montagem." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/14875.

Full text
Abstract:
Made available in DSpace on 2016-04-28T19:59:13Z (GMT). No. of bitstreams: 1 Carlos Eduardo Siqueira Ferreira de Souza.pdf: 1642585 bytes, checksum: 913d09f1c598648bdb032fedee52c11e (MD5) Previous issue date: 2008-10-22
The main objective of this research is to examine, in the writings of Ana Cristina Cesar, the relationships between the texture of her autobiographical discourse and the cinematic editing method, with particular attention to the texts comprised in A teus pés, published in 1982. Such objective was chosen in view of the fact that Ana Cristina Cesar s poetic work reveals composition methods of a singular late 20th century lyrical voice, marked by a fragmentary language, analogous with the cinematic technique of frames juxtaposition and the procedures that account for autobiographical and confessional texts. In order to understand how this woman poet appropriates an autobiographical discourse and transforms it, and whether the cinematic language takes part in the autobiographical construction process of Ana Cristina s poetry through the organization of fragments in the text, we start from the following hypotheses: autobiographism is a lyrical and fictional method in Ana Cristina s fragmentary poetry; cinematic editing provides solutions to the contiguity of analogical images in her poetic writing; fragmentarism is the procedure that brings together the cinematic and the autobiographical discourse. Such hypotheses were tested in the light of: Bakhtin s reflections in Aesthetics of Verbal Creation, which deal with confessional and autobiographical genres; the concept of biographeme as proposed by Roland Barthes; and the cinematic editing studies carried out by theoreticians and scholars such as Sergei Eisenstein, Ismail Xavier, Peter Burger and Modesto Carone Netto. We conclude that Ana Cristina Cesar brings together the depragmatizing, self-reflexive tendency of modern art and the disillusioned, faithless attitude of our contemporary age, by deconstructing in her writings the concepts of identity and authorship, in an attempt to depersonalize the self. In the texts written by this woman poet from Rio de Janeiro, the biographeme is apprehended as a fragmentary and non-linear composition method which, together with the frames juxtaposition procedure that constitutes cinematic editing, results in a unique relationship between reality and fiction, achieved by means of an erotic texture in which a reality that emerges and disappears from the text is displayed. Bringing forth a dramatic interplay in which the poetic persona takes to the stage and displays its multiplicity to the reader, Ana Cristina Cesar s writing reveals that the theatralization of the self on the textual stage is an alternative to the invention of a creative and liberating identity
O principal objetivo desta pesquisa é examinar, na escritura de Ana Cristina Cesar, em especial nos textos que compõem A teus pés, editado em 1982, as relações entre a tessitura do discurso autobiográfico e o método de montagem cinematográfica. Tal objetivo foi traçado, considerando-se que a obra poética de Ana Cristina Cesar revela, como métodos de composição de uma voz lírica singular do final do século XX, a linguagem fragmentária, análoga à técnica cinematográfica de justaposição de planos, e os procedimentos constituintes de textos autobiográficos e confessionais. A fim de compreendermos como a poeta se apropria do discurso autobiográfico, transformando-o, e se a linguagem cinematográfica participa, por meio da organização de fragmentos no texto, do processo de construção do autobiografismo na poesia de Ana C., partimos das seguintes hipóteses: o autobiografismo é um método lírico ficcional na poesia fragmentada de Ana Cristina Cesar; a montagem cinematográfica fornece soluções para a contigüidade das imagens analógicas na escritura poética; o fragmentarismo é um procedimento que alia os discursos cinematográfico e autobiográfico. Tais hipóteses foram testadas à luz: das reflexões elaboradas por Bakhtin, em Estética da criação verbal, sobre os gêneros confessionais e a autobiografia; do conceito de biografema proposto por Roland Barthes; e de estudos sobre a montagem cinematográfica, realizados por teóricos e estudiosos como Sergei Eisenstein, Ismail Xavier, Peter Bürger e Modesto Carone Netto. Concluímos que Ana Cristina Cesar alia a tendência despragmatizante e auto-reflexiva da arte moderna à postura descrente e desiludida da contemporaneidade, desconstruindo, em sua escritura, as noções de identidade e de autoria, numa tentativa de despersonalização do sujeito. Nos textos da poeta carioca, o biografema é apreendido como um método de composição fragmentada e alinear, que, aliado ao procedimento de justaposição de planos que constitui a montagem cinematográfica, constrói uma relação singular entre real e ficção mediante uma tessitura erótica, na qual se estabelece a encenação de uma realidade que aparece e desaparece do texto. Instauradora de um jogo dramático em que o sujeito poético encena sua multiplicidade para o leitor, a escritura de Ana Cristina Cesar revela que a teatralização do eu no palco textual é uma alternativa para a invenção de uma identidade criativa e libertadora
APA, Harvard, Vancouver, ISO, and other styles
26

Hamrat, Sonia. "Etude des échanges thermiques et conception d’un système de refroidissement pour le système de lecture du trajectographe SciFi de LHCb." Thesis, Université Clermont Auvergne‎ (2017-2020), 2017. http://www.theses.fr/2017CLFAC104/document.

Full text
Abstract:
Dans le cadre de l’évolution du plus grand accélérateur circulaire de particules « LHC », un important programme de mise à niveau sur l’ensemble des détecteurs qui le constitue a été lancé. Parmi eux, on retrouve la mise à niveau du détecteur LHCb qui comprend le remplacement complet de plusieurs sous-détecteurs. La fréquence de lecture élevée de 40MHz, sans précédent dans une expérience de physique des particules, et l’environnement de rayonnement sévère lié à l’augmentation de l’intensité du LHC, sont les principaux défis à relever par les nouveaux sous-détecteurs. Le travail présenté dans ce manuscrit, décrit une petite partie de l’évolution du détecteur LHCb. Le développement et la construction d’un nouveau trajectographe à grande échelle, basé sur une nouvelle technologie à fibres scintillantes «SciFi», lues avec des photomultiplicateurs au silicium «SiPM», est l’un des projets clés du programme de mise à niveau de LHCb. La première partie, consiste à étudier les échanges thermiques et à concevoir un système de refroidissement pour chaque Read-Out Box « ROB » qui contient deux cartes électroniques frontales « FE », et qui permettent de lire les données du détecteur. Ces dernières possèdent une dissipation thermique d’environ 110W.Pour assurer le bon fonctionnement des composants électroniques, il est obligatoire de mettre en place un refroidisseur. Des contraintes importantes sont prisent en compte dans cette étude, la première représente l’espace limité en regard du besoin du système de refroidissement, des interfaces électroniques et mécanique, la seconde concerne les SiPM. Reliés à l’électronique par des câbles flexibles, elles sont situées à proximité de l’électronique « FE » et leur température de fonctionnement doit être parfaitement réglée autour des -40°C. Des travaux de simulations numériques sur les logiciels FloTHERM et ANSYS ont été menés sur le banc expérimental réalisé au sein du laboratoire, et qui nous ont permis de déterminer la solution de refroidissement la mieux adaptée. Cette étude nous a aussi montré qu’il est plus que nécessaire d’intégrer des interfaces thermiques « IT» telles que des pâtes thermiques afin d’assurer un meilleur transfert de chaleur entre les composants électroniques et le refroidisseur. La deuxième partie, représente une étude approfondie sur les interfaces thermiques qui sont un point délicat de transfert de chaleur, car elles peuvent avoir plusieurs dizaines de pour cent de la résistance thermique globale. Pour garantir une utilisation adéquate et durable de ces matériaux, plusieurs paramètres ont été vérifiés, en particulier la dureté, la consistance (pas de production de graisse ou d’huile) et la conductivité thermique, grâce à un banc de mesures adapté d’après la méthode normalisé ASTM D5470, grâce auquel on a pu mesurer le flux de chaleur qui traverse l’échantillon d’interface thermique testé et qui est généré par une source chaude et un source froide qui sont montées aux extrémités de notre banc.Grâce à l’installation CHARME (CERN) et à la plate-forme PAVIRMA (Campus des Cézeaux), une série de mesure d’irradiations aux neutrons et aux rayons X sont également effectuées, correspondant à l’environnement dans lequel elles seront exposées dans l’expérience, d’un côté pour identifier les dégradations et changements possibles sur les résistances thermiques par l’analyse de l’impédance thermique, de l’autre pour identifier l’interface thermique qui convient le mieux à notre application et qui permet d’assurer un excellent échange thermique et donc un bon refroidissement de l’électronique frontale au sein du trajectographe du détecteur LHCb
In the context of the evolution of the biggest circular accelerator of particles «LHC», an important program of upgrade on all the detectors which establishes itself was thrown. Among them, we find the upgrade of the detector LHCb which includes the complete replacement of several sub-detectors. The frequency of high reading of 40MHz, an unprecedented in an experiment of physical appearance of particles, and the environment of severe radiation bound to the increase of the intensity of the LHC, are the main challenges by the new sub-detectors. The work presented in this manuscript, described as a small part of the evolution of the LHCb detector. The development and the construction of a new wide-scale tracker, based on a new technology with scintillating fiber «SciFi», read with photomultipliers to the silicon «SiPM», is one of the key projects of the LHCb upgrade program. The first part, consists in studying the thermal exchanges and designing a cooling system for every Read-Out Box «ROB» which contains two electronic front-end « FE », and which allow to read the data of the detector. The latter has a thermal dissipation about 110W. To ensure the smooth running of electronic components, it is compulsory to set up a cooler. Important constraints are taken into account in this study, the first one represents the space limited compared to the need for the cooling system, the electronic interfaces and mechanical, the second concerns the SiPM. Connected with the electronics by flexible cables, they are located near the electronics «FE» and their temperature of operation is perfectly settled around -40 ° C. Works of digital simulations on the software FloTHERM and ANSYS were led on the experimental bench realized within the laboratory, and which allowed us to determine the best adapted solution of cooling. This study also showed to us that he is more than necessity to integrate thermal interfaces «IT» such as thermal pastas to assure a better transfer of heat between electronic components and cooler. The second part, represents an in-depth study on the thermal interfaces which are a delicate point of transfer of heat, because they can have dozens percent of the global thermal resistance. To guarantee an adequate and sustainable use of these materials, several parameters were verified, in particular hardness, consistency (no production of fat or oil) and the thermal conductivity, thanks to a bench of measures adapted according to the method normalized ASTM D5470, with this bench we could measure the flow of heat through the tested thermal interface sample and which is generated by a hot source and a cold source that are mounted at the ends of our bench.With the installation CHARME (CERN) and PAVIRMA (Cézeaux), a series of measure of irradiations at the neutrons and the X-rays are also made, correspond-ing to the environment in which they will be exposed in the experience, on one side to identify the damages and the possible changes on the thermal resistances by the analysis of the thermal impedance, the other one to identify the thermal interface which suits best our application and which allows to assure an excellent thermal exchange and thus a good cooling of the frontal electronics within the trajectographe of the detector LHCb
APA, Harvard, Vancouver, ISO, and other styles
27

Kabanuk, Steven Joseph. "Nonhierarchical alternate routing in a circuit-switched network at Telus." Thesis, 2001. http://hdl.handle.net/2429/11318.

Full text
Abstract:
The primary objective of this project was to identify opportunities and develop solutions that will enable TELUS to reduce the cost of maintaining and improving a portion of their existing local network in British Columbia, Canada. To realize this objective, the focus was on optimal routing of calls assuming a fixed network capacity. Our hypothesis was that by changing the routing rules between an origin switch and a destination switch, we could alleviate pressure from congested areas in the network by diverting traffic through less utilized areas. Three types of optimization models have been developed: two linear programs, a mixed-integer model, and a nonlinear program. Irrespective of their objective functions, the purpose of each model was to suggest new sets of routes for each pair of switches. Development of these models and assessment of their ability to suggest routes which reduced the number of blocked calls in the simulated network was the central focus of this thesis. The modeling results were compared with the existing routing.rules in a network simulator. It appears that TELUS could benefit from implementation of alternate nonhierarchical routing rules. Specifically, employing the combined routing rules - that attempt the direct route first, then attempt the 2-link Maximum Linear Model routes from the 11:00-12:00 time interval, and finally the currently used alternate routes - generated the best routing table of those tested. Furthermore, these routing rules can be employed throughout the day without the need for change. The results from the trunk reservation analysis suggest that implementation of a uniform policy would be of marginal value.
APA, Harvard, Vancouver, ISO, and other styles
28

Mojica, Tomas. "Developing and implementing industrial engineering methods for process improvement at Telus communications." Thesis, 2004. http://hdl.handle.net/2429/15363.

Full text
Abstract:
TELUS, a large Canadian telecommunications company primarily based in Western Canada, provides a full range of telecommunications products and services including data, Internet protocol (IP), voice and mobile wireless services. Every month TELUS processes high volumes of customer orders either for new service or changes in existing service. Within TELUS, the Assignment and Activation group processes all orders and is responsible for changes in the mainframe computers and switches as well as coordination with field service representatives that actually perform physical installations of and changes to customer equipment. The challenges faced by the order processing center include difficulty meeting current throughput and lead time requirements, as well as uncertainty regarding the metrics used for quality and process measurement. Further, increased competition in the telecommunications industry has pressured TELUS to cut costs, resulting a major workforce reduction and widespread process and service reorganization. This thesis describes the development and application of simulation to study the Assignment and Activation group. The data analysis and model development procedure is outlined and results are discussed. Although simulation model development was hindered by difficulties collecting process data, the model building and data analysis process helped identify several opportunities for improvement. The steps required to continue developing the simulation, therefore enabling more detailed questions about the process to be evaluated, are also outlined. Based on the simulation analysis it is recommended that better data collection be implemented to measure key metrics, especially processing time distributions. Putting the uncertainty in the confidence level of the processing estimates aside, this study found that improving the Auto Front End Assignable or the exception rates would have a negligible effect on throughput if the processing times are close to average. In addition, shifting the days out ahead by three days resulted in a 3% increase in on-time completions. Finally in most of the scenarios evaluated, the operator utilization appeared unrealistically high indicating a general staff shortage.
APA, Harvard, Vancouver, ISO, and other styles
29

Piercy, Joanna Carolyne. "Estimating metabolic rate in tegu lizards (Tupinambis merianae) : can one calculate oxygen consumption from heart rate?" Thesis, 2005. http://hdl.handle.net/2429/16666.

Full text
Abstract:
There are a number of methods commonly used to estimate metabolic rate in animals, one of which is the Heart Rate Method. Heart rate (f[sub H]) can theoretically be used as a direct proxy for O₂ consumption (V[sub O]) according to Fick's equation (V[sub O] = f[sub H] x O₂ pulse) as long as the O₂ pulse varies in a predictable manner. The benefit of this method is that heart rate is easily monitored both in the lab and in the field, is sensitive to short-term changes in activity, and can be monitored continuously on the order of weeks or months. Studies have confirmed that in some birds, mammals, and at least one species of reptile, the accuracy of this method is at least as great as that of the doubly-labelled water method. My goal was to determine if heart rate can be used as a reliable estimate of metabolic rate in tegu lizards. To this end, f[sub H] and V[sub O] were measured simultaneously in fasting lizards at 17°C, 27°C and 37°C, and in digesting lizards at 37°C. Regression analysis showed that, at any given temperature or digestive state, the relationship between f[sub H] and V[sub O] was highly variable between individuals (as indicated by different slopes and intercepts) as well as within individuals (as indicated by low r² values). Regression analysis on data pooled within each treatment failed to account for this variability. However, regression analysis of the dataset in its entirety accounted for 740/0 of the variability. The equation which best described the relationship in unstressed animals was lnsV[sub O] = —3.441 + 0.679 InF[sub R]. Predictions of total metabolic rate calculated from this general calibration equation were typically more accurate than predictions based on the Time Energy Budget method.
Science, Faculty of
Zoology, Department of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
30

Sobral, Ana Filipa dos Santos 1983. "Os meus, os teus e os nossos : gerir e motivar trabalhadores em relações triangulares de emprego." Doctoral thesis, 2015. http://hdl.handle.net/10451/22516.

Full text
Abstract:
Tese de doutoramento, Psicologia (Psicologis dos Recursos Humanos, do Trabalho e das Organizações), Universidade de Lisboa, Faculdade de Psicologia, 2015
Nesta tese de doutoramento exploraram-se as percepções das práticas de gestão de recursos humanos (PGRH), enquanto método de comunicação entre empresas e trabalhadores contingentes em formatos triangulares de emprego, nomeadamente trabalhadores temporários de agência (TAW) e trabalhadores em outsourcing (OW). Foi ainda avaliado como a percepção das PGRH e as trocas sociais que origina, podem estar condicionadas por factores de variabilidade como: gerações, motivações, setor ou formato de contratação contingente. Com o primeiro estudo pretendeu-se adequar uma escala de percepção do sistema de PGRH a trabalhadores contingentes em relações triangulares de emprego. Para tal, foram testados os princípios de Messick (1995) numa população de 4451 TAW portugueses e considerada a relação de troca entre a medida, o duplo compromisso afectivo destes trabalhadores e dois setores de atividade distintos (i.e., serviços e indústria). Desenhado como ponto de partida, este primeiro estudo é transversal a toda a investigação. A medida aqui criada, adaptada e validada, esteve presente como variável central dos três estudos seguintes. No segundo estudo, adicionou-se uma outra perspectiva à análise das relações laborais dos trabalhadores contingentes em formatos triangulares de emprego: o efeito geracional nas relações de troca entre as PGRH, o duplo compromisso e o desempenho auto-percepcionado. Ao considerar como as diferentes gerações (Baby Boomers, 1943-1965; Geração X, 1966-1980; e Geração Y, 1981-1995) experienciam as transformações do mercado e os novos formatos de emprego, este estudo, reconhece e incorpora as mudanças sociais que têm vindo a ocorrer no mercado de trabalho e, por isso, lida diretamente com a crescente diversidade geracional no trabalho contingente. As hipóteses foram testadas com uma amostra de 3786 TAW e os resultados sugerem que as gerações podem ter um efeito moderador nas relações estudadas. Quanto ao terceiro estudo, este centrou o seu foco nas motivações dos trabalhadores e ambicionou a criação de uma tipologia motivacional capaz de amplamente captar as razões, mais ou menos autónomas, que levam os trabalhadores a enveredar por numa situação de trabalho contingente. Porém, o núcleo deste estudo continuou a ser a percepção do sistema de PGRH e o duplo compromisso destes trabalhadores, usando agora as motivações e os perfis criados, como factor de variabilidade na análise destas construtos. No final foi possível identificar, numa amostra de 3766 TAW, cinco perfis que se diferenciaram quanto aos níveis do duplo compromisso afetivo e da percepção das PGRH. Por último, o quarto estudo replicou parte da análise feita no estudo anterior, mas desta vez adicionando dois novos factores de variabilidade: o setor e o formato de contratação contingente. Este estudo permitiu a construção de uma tipologia de perfis motivacionais no setor do contact center, a comparação entre perfis motivacionais de OW e TAW dentro de uma mesma amostra e a análise da relação destes perfis com a percepção das PGRH e o compromisso afectivo para com a empresa contratante. As hipóteses foram testadas com uma amostra de 2078 trabalhadores contingentes e seis perfis foram identificados. De acordo com os resultados, ser OW ou TAW pode influenciar diferentemente as motivações dos trabalhadores, mas não a relação das motivações com outras variáveis, designadamente: as PGRH e o duplo compromisso afectivo. Através deste estudo, foi ainda possível explorar as especificidades do setor dos contact center.
The present thesis explores the perceptions of the human resources practices (HRP) as a method of communication between companies and contingent workers in triangular employment relations, namely temporary agency workers (TAW) and outsourcing workers (OW). The studies examined the influence of different variability factors, such as: generations, motivations, sector and contingent work formats, on the workers’ perceptions of the HRP and their exchange relationship, both with the contractor and the client company. The first study developed and assessed the psychometric properties of an HRP system measure for contingent workers and cross-validated it with workers’ affective commitment towards both companies that are involved in this employment relation. The measure was administered to 4451 Portuguese TAW. The Messick’s validation framework (1995) was used and two sectors were compared (i.e., services and industry). This measure was a central variable of the following three studies. The second study explored a moderated mediation model that accounts for contingent workers affective commitment (toward the agency and the client company) and generation (Baby Boomers, 1943-1965; Generation X, 1966-1980; and Generation Y, 1981-1995) in the relationship HRP perceptions and overall perceived performance. By considering, simultaneously, the growth of the new work arrangements and the rising of a multigenerational workforce, this study incorporates the changes in the labor market and advances literature by studying the generational diversity inside the contingent work. The hypotheses were tested with a sample of 3786 TAW. Results suggested that generations moderate the relationships herein studied. Regarding the third study, it created a motivation profile typology, capable of broadly capture the workers' autonomous and extrinsic reasons for being in their current work situation. Five distinct motivation profiles were found on a sample of 3766 TAW. Moreover, by using the profiles as a variability factor, it was possible to understand that they differed in their affective commitment to the agency and to the client-company, and in the perception of the HRP. Finally the fourth study replied part of the analysis done in the previous study, but this time adding two other variability factors: sector and contingent work format. Therefore, the last study built a motivation profile typology of contingent workers in the contact center and compared OW and TAW profiles, and its relation with HRP perceptions and affective commitment toward the contractor. The hypotheses were tested in a sample of 2078 Portuguese contingent workers. Six profiles were identified. As expected, being OW or TAW can influence workers motivations. However, the contingent employment format did not moderate the relationship between motivation, HRP perceptions and affective commitment. Through this study, it was also possible to explore the specifics of the contact center sector.
APA, Harvard, Vancouver, ISO, and other styles
31

Haroun, Amal. "Impact des propos humoristiques des jeunes Égyptiens tenus durant le printemps arabe (2011-2015) sur les représentations politiques du chef d'État égyptien : contexte, dynamiques et évolution." Thèse, 2016. http://hdl.handle.net/1866/18326.

Full text
Abstract:
Ce mémoire analyse le phénomène de l’humour politique envers les chefs d’État égyptiens (Moubarak, Moursi et Es-Sissi) sur les places publiques et sur les réseaux sociaux durant les soulèvements du printemps arabe entre 2011 et 2015 qui furent remplis de tumultes, de divisions et de déceptions. L’humour politique était très présent dès le premier moment et a non seulement joué un rôle important comme marqueur de transformations dans le système politique, mais aussi comme marqueur du déroulement d’un drame social qui connaît des phases d’évolution et de régression, voire un retour vers un point de départ. Alors que la symbolique du chef d’État égyptien implique la mobilisation d’une image locale d’Ibn El Balad (égyptien authentique et fils du pays), père et unificateur d’un peuple sensible à son héritage millénaire et à ses traditions, l’humour politique reflète à la fois les aspirations des jeunes activistes branchés sur le monde pour une société civile basée sur le respect des droits de la personne et le rappel populaire constant des valeurs traditionnelles fondatrices de la nation égyptienne que le président égyptien doit incarner, soit la famille et la religion. Même si le tabou du président est brisé, le champ politique semble retourner vers un point de départ. Le peu de libéralisme gagné avec ces tumultes révolutionnaires depuis cinq ans se trouve détourné et devient plutôt un signe négatif dans une société qui, une fois revenue à la normale, demeure profondément conservatrice.
This thesis analyzes the phenomenon of political humor to the head of the Egyptian State (Mubarak, Mursi and Es-Sissi) on public squares and on social networks during the Arab Spring uprisings between 2011 and 2015, which was a period of turmoil, divisions and disappointments. Political humor was very present from the first moment, and has not only played an important role as a marker of changes in the political system, but also as a marker of the progress of a social drama who knows evolution and regression phases, or even a return to a starting point. While the symbolism of the Egyptian head of state involves the mobilization of a local image of Ibn El-Balad (authentic Egyptian and son of the country), father and unifier of a people sensitive to its old heritage and traditions, political humor reflects both the aspirations of young activists globally connected to a civil society based on respect for human rights and the constant reminder of traditional values, founders of the Egyptian nation that the Egyptian President must embody, such as family and religion . Although the taboo president is broken, the political field seems to return to a starting point and limited liberalism gained with these revolutionary turmoil for five years is hijacked and becomes a more negative sign in a society which, once returned to normal rest deeply conservative.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography