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On the determination and evolution of fabric in representative elementary volumes for a sand specimen in triaxial compressionSchmidt, Selma, Wiebicke, Max, Herle, Ivo 03 November 2022 (has links)
The soil response in triaxial compression tests, that are commonly treated as element tests, is known to be inhomogeneous. Several studies have revealed the localisation of deformation throughout the whole specimen by digital image correlation techniques on X-ray tomographies. The fabric of a soil specimen has so far only been studied on complete specimens as a bulk measurement or in chosen subsets. In this contribution, we present a study on the spatial and temporal distribution of the fabric throughout one Hostun sand sample in triaxial compression. Therefore, we calibrated the minimum representative element size first for three chosen fabric variables considering three different criteria. By distributing the elements in a regular grid over the specimen, we are able to clearly identify the onset of the localisation in terms of void ratio, coordination number and contact fabric anisotropy. Spatially and temporally the contact fabric variables precede the void ratio changes as they are much more sensitive to small changes.
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Академическая мобильность студентов из Российской империи в первой половине XIX в. (на примере Гейдельбергского университета) : магистерская диссертация / Academic Mobility of Students from the Russian Empire in the First Half of the Nineteenth Century (Case of the Heidelberg University)Ширанова, Е. А., Shiranova, E. A. January 2018 (has links)
Диссертационное исследование посвящено образовательным поездкам российских студентов в Гейдельбергский университет в первой половине XIX в. Исследования по истории академической мобильности показывают тенденции этого процесса в прошлом и позволяют более широко взглянуть на образовательные связи между государствами. На основе данных университетских матрикул и справочной литературы была создана электронная таблица российских студентов и затем обработана при помощи статистического пакета. Всего за период 1800–1850 гг. было отобрано 285 студентов из Российской империи. На основе полученных комбинационных таблиц был составлен коллективный портрет российского студенчества по признакам возраста, вероисповедания, социального происхождения, выбора факультета, региональной принадлежности и предыдущего места обучения. Результаты исследования могут стать базой для работ по разным вопросам российско-германских связей и, в особенности, для сравнения академической мобильности российских студентов первой половины XIX в. с другими периодами или регионами. / The dissertation is devoted to academic trips of Russian students to the Heidelberg University during the first half of the 19th century. Writings on the history of academic mobility demonstrate its tendencies in the past and allow examining international educational contacts in a wider perspective. An electronic database of the Russian students in the Heidelberg University was created based on the data of university matricula and corresponding background materials. Then the data were processed in the Statistical Package for the Social Sciences (SPSS). 285 students from the Russian Empire who studied in the Heidelberg University during 1800–1850 were chosen. A collective portrait of the Russian studentry was compiled including such characteristics as age, confession, social background, regional background, choice of faculty, and previous place of education. The results of the current research can be applied in studies on various aspects of Russian and German contacts and, particularly, on comparison of academic mobility of Russian students either in other regions or in other periods.
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Исследование взаимосвязи психологического одиночества и личностных черт «темной триады» у женщин : магистерская диссертация / Research on the relationship between psychological loneliness and the personality traits of the «dark triad» in womenСоболева, И. В., Soboleva, I. V. January 2023 (has links)
Объектом исследования явились психологическое одиночество и комплекс личностных черт «темная триада». Предметом исследования стала взаимосвязь психологического одиночества с личностными чертами «Темной триады» у женщин. Магистерская диссертация состоит из введения, двух глав, заключения, списка литературы (63 источника) и приложения, включающего в себя бланки применявшихся методик. Объем магистерской диссертации 93 страницы, на которых размещены 6 рисунков и 9 таблиц. Во введении раскрывается актуальность проблемы исследования, разработанность проблематики, ставятся цель и задачи исследования, определяются объект и предмет исследования, формулируются основная и дополнительная гипотезы, указываются методы и эмпирическая база, а также этапы проведения исследования, научная новизна, теоретическая и практическая значимость работы. Первая глава включает в себя обзор иностранной и отечественной литературы по теме психологического одиночества и комплекса личностных черт «темной триады». Представлены разделы, посвященные исследованию подходов и типологии в изучении психологического одиночества, исследованию структурных показателей комплекса «темной триады», их взаимосвязь и специфику переживания женского одиночества. Выводы по первой главе представляют собой итоги по изучению теоретического материала. Вторая глава посвящена эмпирической части исследования. В ней представлено описание организации и методов проведенного исследования и результатов, полученных по всем использованным методикам: анкете (пол, возраст, статус в браке, наличие детей, родителей, трудовая занятость), опроснику для определения вида одиночества С. Г. Корчагиной, дифференциальный опроснику переживания одиночества Е.Н. Осина и Д.А. Леонтьева, короткому опроснику темной триады в адаптации М.С. Егоровой, М.А. Ситниковой, О.В. Паршиковой. Также во второй главе представлен корреляционный и сравнительный анализ результатов исследования. В заключении в обобщенном виде изложены результаты теоретической и эмпирической частей работы, а также выводы по выдвинутвм гипотезам, обоснована практическая значимость исследования и описаны возможные перспективы дальнейшей разработки данной проблематики. / The object of the study was psychological loneliness and a complex of personality traits «dark triad».
The subject of the study was the relationship of psychological loneliness with the personality traits of the «Dark Triad» in women. The master's thesis consists of an introduction, two chapters, a conclusion, a list of references (63 sources) and an appendix, which includes forms of the methods used. The volume of the master's thesis is 93 pages, which contain 6 figures and 9 tables. The introduction reveals the relevance of the research problem, the development of the problem, sets the goal and objectives of the study, defines the object and subject of the study, formulates the main and additional hypotheses, indicates the methods and empirical base, as well as the stages of the study, scientific novelty, theoretical and practical significance of the work. The first chapter includes a review of foreign and domestic literature on the topic of psychological loneliness and the complex of personality traits of the «dark triad». The sections devoted to the study of approaches and typology in the study of psychological loneliness, the study of the structural indicators of the «dark triad» complex, their relationship and the specifics of experiencing female loneliness are presented. The conclusions on the first chapter are the results of the study of theoretical material.
The second chapter is devoted to the empirical part of the study. It presents a description of the organization and methods of the study and the results obtained by all the methods used: a questionnaire (sex, age, marital status, the presence of children, parents, employment), a questionnaire to determine the type of loneliness by S. G. Korchagina, a differential questionnaire feelings of loneliness E.N. Osina and D.A. Leontiev, a short questionnaire of the dark triad adapted by M.S. Egorova, M.A. Sitnikova, O.V. Parshikova. The second chapter also presents a correlation and comparative analysis of the results of the study. In conclusion, the results of the theoretical and empirical parts of the work, as well as conclusions on the hypotheses put forward, are summarized, the practical significance of the study is substantiated, and possible prospects for further development of this issue are described.
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Chromatin folding in health and disease: exploring allele-specific topologies and the reorganization due to the 16p11.2 deletion in autism-spectrum disorder.Kempfer, Rieke 09 November 2020 (has links)
Die 3D Struktur von Chromosomen im Zellkern reguliert verschiedene Funktionen in der Zelle und Fehler in der 3D Faltung des Genoms können pathogen sein. 3D Genomfaltung kann mit verschiedenen Methoden untersucht werden um Chromatinkontakte, sowie die Position von DNA in Relation zu sub-nuklearen Bereichen oder der Kernmembran zu detektieren. Hier verwende ich GAM und Hi-C um zwei Aspekte der 3D Genomtopologie zu untersuchen, die Allelspezifität von Chromatinkontakten und Kontakte zwischen Chromosomen. Ich untersuche allelspezifische Kontakte in murinen embryonalen Stammzellen und Interaktionen zwischen Chromosomen im Zusammenhang mit Autismus Spektrum Störung auf ihre Relevanz in der Regulation von Genen.
Zur allelspezifischen Detektion von Chromatinkontakten generierte ich einen GAM Datensatz der tausende von nuklearen Cryodünnschnitten enthält. Die Generierung dieser Daten beinhaltete die Entwicklung einer verbesserten Version der GAM Methode zur Produktion von großen Datensätzen in Hochdurchsatz. Hier zeige ich, dass GAM effizient Haplotyp-spezifische Chromatinkontakte bestimmen kann. Erste Untersuchungen von allelspezifischer 3D Genomtopologie zeigten weitreichende Unterschiede zwischen den Allelen, welche „A/B compartments“ und spezifische Chromatinkontakte beinhalten, wie zum Beispiel am Imprinting Locus H19/Igf2.
Zur Untersuchung von interchromosomalen Kontakten detektierte ich Chromatinkontakte mit Hi-C im Kontext einer genomischen Deletion am humanen 16p11.2 Locus, assoziiert mit Autismus Spektrum Störung. Ich zeige hier, dass die Deletion am 16p11.2 Locus zu der Reorganisation von spezifischen interchromosomalen Kontakten zwischen 16p11.2 und Chromosom 18 führt, und stelle eine Hypothese auf wie diese interchromosomalen Kontakte zur ektopischen Aktivierung von Pcdh Genen auf Chromosom 18 führen. Protocadherins haben wichtige Funktionen in neuronaler Konnektivität, ein Prozess dessen Störung zur Manifestierung von Autismus Spektrum Störung beitragen könnte. / The 3D folding of interphase chromosomes inside the nucleus regulates important nuclear functions and once disrupted can lead to the manifestation of disease. Different techniques can be used to map 3D genome folding and detect pairwise and multiway interactions of the genome, or map the positions of DNA with respect to subnuclear compartments or the nuclear lamina. Here, I use GAM and Hi-C to explore two aspects of 3D genome topology, the allele specificity of chromatin contacts and long-range contacts between chromosomes, respectively. I detect specific contacts of the parental alleles in mouse embryonic stem cells and interactions between chromosomes in the context of congenital disease and study them with regard to their functionality and importance in mammalian gene regulation.
For detecting chromatin contacts with allele specificity, I produced a GAM dataset containing thousands of nuclear slices. The collection of this data was accompanied by the development of a high-throughput version of GAM that allows the generation of large datasets. I show that GAM can determine haplotype-specific chromatin contacts with high efficiencies. First explorations of allele-specific chromatin topologies reveal many differences between the parental alleles, including allele-specific compartments A and B, and specific chromatin contacts, for example at the imprinted H19/Igf2 locus.
For the exploration of inter-chromosomal contacts in disease, I mapped chromatin interactions with Hi-C in the context of a CNV at the human 16p11.2 locus, associated with autism spectrum disorders. Here, I show that the deletion at the 16p11.2 locus results in the rearrangement of specific inter-chromosomal contacts between the 16p11.2 locus and chromosome 18 and propose a role for these inter-chromosomal contact changes in the upregulation of the nearby Pcdhb gene cluster, which comprises protocadherin genes with important functions in neuronal connectivity during development.
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British Women’s Views of Twentieth-Century India: An Examination of Obstacles to Cross-Cultural UnderstandingsBhattacharjee, Dharitri 27 August 2007 (has links)
No description available.
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Autorité, parole et pouvoir : une approche anthropologique de l'activité néologique inuit au NunavutCancel, Carole 18 April 2018 (has links)
Dans une approche qui met à profit les apports de l’anthropologie nord-américaine et de l’ethnolinguistique européenne, la thèse étudie l’activité néologique inuit concertée au Nunavut, appelée taiguusiliurniq. Dans un premier temps, y sont examinés en diachronie les rapports de force linguistiques que les Inuit de l’Arctique oriental canadien ont entretenus au fil des siècles avec les explorateurs, les baleiniers, les marchands, les missionnaires, et enfin l’administration, et qui constituent l’arrière-plan sur lequel se sont arrimés les métiers de la traduction en langue inuit et les débuts de l’institutionnalisation de l’innovation lexicale. La deuxième partie s’intéresse à l’émergence de la terminologie propre à la sphère publique et aux défis que pose sa normalisation sur le plan juridique, technique, linguistique et culturel. La dernière partie est consacrée à un examen minutieux de cette terminologie, alimenté par des données issues d’un travail de compilation lexicale et par la description détaillée d’un atelier de développement terminologique. Sous la forme d’une synthèse, sont mises au jour les bases productives et affixes récurrents, l’adoption des modes de désignation, les questions liées au découpage du réel et enfin les caractéristiques et défis actuels de la langue inuit en tant que langue spécialisée, dans un contexte où la parole contribue à pérenniser les rapports d’autorité et de pouvoir. Élaboré sous la forme d’une matrice, le lexique analytique trilingue (inuktitut-français-anglais), placé en annexe, constitue un outil d’analyse voué à nourrir la réflexion d’ordre lexicologique engagée par les professionnels de la langue inuit au Nunavut. Mots clés : Inuit, inuktitut, ethnolinguistique, néologie, lexicologie, parole, autorité, pouvoir, Nunavut, Arctique canadien / Using North American anthropology and European ethnolinguistics in a combined approach, this thesis studies Inuit neological activity undertaken in concerted action, called taiguusiliurniq. The first part examines diachronically the relations of power as regards language maintained over centuries between the Inuit of Eastern Arctic Canada and explorers, whalers, merchants, missionaries and finally with the administration; all of these making up the background on which arose the professions of interpreters and translators working with Inuktitut, along with the early days of institutionalized neology. The second part deals with the emergence of the terminology specific to the public sphere and to the challenges of its standardization in legal, technical, linguistic and cultural terms. The last part offers a careful examination of this terminology, fueled by data extracted from the creation of a lexicon and by a detailed description of a terminology development workshop. In a synthetic format, recurrent verb and noun roots along with affixes are highlighted, as well as choices regarding modes of designation, and the current challenges of Inuit language as a specialized language in a context where speech plays a part in the perpetuation of the relations of power and authority as regards language. Developed as a matrix, the trilingual analytical lexicon (Inuktitut-French-English) placed in the appendix is designed as an analytical tool meant to feed the lexicological reflection that Nunavut Inuit language professionals are engaged in. Keywords: Inuit, Inuktitut, ethnolinguistics, neology, lexicology, speech, authority, power, Nunavut, Canadian Arctic
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Suomen yleiskielestä poikkeava ruotsinsuomen sanasto : Kuvaus ruotsinsuomen omasta sanastosta ja siihen liittyvistä asenteista / Sverigefinska ord som inte förekommer i standardfinska : Beskrivning av sverigefinska ord samt attityder förknippade med dessaLarsson, Tarja January 2024 (has links)
Uutta ruotsinsuomalaista sanastoa kehittyy pääasiassa kahdella tavalla. Eniten uutta sanastoa syntyy epävirallisissa keskustelutilanteissa, mutta sanastoa luodaan myös tietoisesti, kun Kielenja kansanperinteen tutkimuslaitos antaa suosituksia esimerkiksi Ruotsin viranomaisten nimienkääntämisestä. Tämän tutkimuksen tarkoituksena on selvittää, millaisia suomen yleiskielestä poikkeavia suomen sanoja Ruotsissa käytetään, ketkä niitä käyttävät sekä millaisia asenteitatällaisen sanaston käyttöön liittyy. Ruotsinsuomalaiselle vähemmistölle on tärkeää, että heidän kieltään tutkitaan, sillä siten voidaan kartuttaa tietoa vähemmistöstä, saada heidän käyttämästään kielestä tutkimukseen perustuvaa tietoa ja vahvistaa heidän ruotsinsuomalaista identiteettiään. Tutkimuksen empiirisenä aineistona on toisaalta Ruotsin radion suomenkielisen toimituksenvuosina 2016–2023 järjestämissä Vuoden ruotsinsuomalainen sana -äänestyksissä ehdotetut sanat ja toisaalta ruotsinsuomalaisten sanojen käyttöä ja sanoihin liittyviä asenteita kartoittava verkkokysely. Olen lajitellut äänestyksissä ehdotetut sanat lainasanatyypin, sanaluokan jaaihepiirin mukaan. Kyselytutkimuksessa olen analysoinut sekä määrällisen tiedon että vastauksia täydentävät vapaamuotoiset perustelut. Vuoden ruotsinsuomalainen sana -äänestysten aineistosta tehty tutkimus osoittaa, että suurin osa aineistossa esiintyvistä ruotsinsuomen sanoista on niin kutsuttuja erityislainoja eli ruotsistasuomen kieliasuun mukautettuja lainasanoja. Sanojen aihepiirit kuvastavat etupäässä kielenkäyttäjien arkeen liittyviä teemoja. Ruotsissa asuvien suomen puhujien keskuudessa toteutettu kyselytutkimus osoittaa, että ruotsinsuomen sanoja käytetään eniten puheessa mutta melko paljon myös vapaamuotoisessa kirjoituksessa. Nuoremmat ikäryhmät käyttävät tämäntyyppisiä sanoja vanhempia ikäryhmiä enemmän ja myös suhtautuvat niiden käyttöön myönteisemmin. / Nya sverigefinska ord skapas i huvudsak på två olika sätt. De flesta av de nya orden bildas iinformella diskussionssituationer, men ord och termer skapas också medvetet när Institutet förspråk och folkminnen ger rekommendationer om till exempel översättning av svenska myndigheters namn till finska. Syftet med denna studie är att ta reda på vilken typ av finska ordsom inte ingår i standardfinska som används i Sverige, vilka som använder dessa ord samt vilka attityder som förknippas med användningen av sådana ord. För den sverigefinska minoriteten är det viktigt att deras språk studeras. På så sätt kan man öka kunskapen om minoriteten, få fram forskningsbaserad information om det språk minoriteten använder samt stärka dess sverigefinska identitet. Det empiriska materialet i undersökningen utgörs dels av de föreslagna orden i omröstningarna Årets sverigefinska ord som Sveriges Radios finskspråkiga redaktion har arrangerat under åren 2016–2023, och dels av en webbenkät som kartlägger användningen av sverigefinska ord samt attityder förknippade med användningen av dessa. Jag har kategoriserat de i omröstningarna föreslagna orden efter typ av lånord, ordklass och ämnesområde. I enkätundersökningen har jag analyserat både kvantitativa uppgifter och de fritt formulerade motiveringarna som kompletterar svaren. Undersökningen av de sverigefinska orden som förekommer i omröstningarna Årets sverigefinska ord visar att de flesta orden är så kallade främmande ord, det vill säga lånord från svenska till finska som är anpassade till finskans ortografi. Ordens ämnesområden speglar främst språkbrukarnas vardag. Enkätundersökningen bland talare av finska i Sverige visar att sverigefinska ord används mest i tal men relativt mycket även i informella texter. Yngre åldersgrupper använder denna typ av ord mer än äldre åldersgrupper och förhåller sig också mer positiva till användningen av dem. / Sweden Finnish vocabulary is developed mainly in two ways. Most of the new vocabulary is created in situations of informal communication, but vocabulary is also consciously created when Language Advisors of Finnish at the Institute for Language and Folklore make recommendations on, for example, translation of names of Swedish authorities into Finnish. The purpose of this study is to examine what types of Finnish words deviating from the Finnish standard language that are used in Sweden, who uses them, and what kind of attitudes are involved in the use of such vocabulary. For the Sweden Finnish minority, it is important that their language is studied, as this will contribute to a wider knowledge of the minority, further research-based knowledge about the language they use, and strengthen their Sweden Finnish identity. The empirical material used for the study is, on the one hand, the words proposed in the Sweden Finnish Word of the Year votes organised by the Swedish Radio in 2016 to 2023, and, on the other hand, an on-line survey on the use of Sweden Finnish words and attitudes related to these. I have analysed the words proposed in the votes by type of loan word, word class and subject matter. For the survey, I have analysed both the quantitative data and the respondents’ arguments supporting their answers. The study of the words proposed in the Sweden Finnish Word of the Year votes indicates that most of the words are so-called special loans, i.e. loan words adapted to the Finnish language structure. The topics of the words mainly reflect the everyday life of language users. A survey among Finnish speakers living in Sweden shows that Sweden Finnish words are used mostly in speech but quite often also in informal writing. Younger speakers use these types of words more than older speakers and also show more positive attitudes towards the use of these words.
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An evaluation of the role of the university of the third age in the provision of lifelong learningHebestreit, Lydia Karola 30 November 2006 (has links)
During the past thirty years several models for lifelong education after retirement have been developed worldwide, one of them being the University of the Third Age (U3A). This study explored the contributions of the U3A to the educational needs of older adults and evaluated the benefits they perceived from their participation in U3A by means of a literature study and an empirical investigation. The latter used a survey to explore the experiences of U3A members of two U 3As and presidents of 68 U3As in Victoria, Australia by means of two different questionnaires. As only 1.47 percent of the over-55 population of Victoria are U3A members, the survey also investigated barriers to U3A participation in general and with special reference to the male population. The findings indicated that member respondents were very satisfied with their U3A experiences which had made substantial differences in their lives. Both male and female respondents saw personal, mental, social, and physical improvement as a result of U3A participation. The majority indicated that participation had improved their intellectual development. Significant differences in the perceptions of male and female participants emerged: female members outnumbered males by three to one. Both the presidents and the members expressed some programmatic concerns, primarily obtaining tutors and classroom availability. The subject areas covered by courses presented were extensive. There was a difference in the subjects desired by males and female respondents; very few courses are offered in science and economics. Some barriers to participation identified are a lack of awareness of U3A, the stereotypical attitudinal barrier of `I am too old' and negative past educational experiences. Moreover, U3As should increase marketing endeavours. Although most U3As advertise, almost a third of the respondents indicated that they would have joined earlier if aware of U3As. A contributing factor appears to be a virtual lack of research and information provided in educational academic journals and other media about lifelong education after retirement. Based on the findings, recommendations were made for future research and for improved practice in the U3A environment as a means to enhance the quality of life for older adults. / Educational Studies / D.Ed. (Comparative Education)
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Optimisation des protocoles de routage dans les réseaux multi-sauts sans fil à contraintes. / Routing protocol optimization in challenged multihop wireless networksMedjiah, Samir 10 October 2012 (has links)
Durant ces dernières années, de nombreux travaux de recherches ont été menés dans le domaine des réseaux multi-sauts sans fil à contraintes (MWNs: Multihop Wireless Networks). Grâce à l'évolution de la technologie des systèmes mico-electro-méchaniques (MEMS) et, depuis peu, les nanotechnologies, les MWNs sont une solution de choix pour une variété de problèmes. Le principal avantage de ces réseaux est leur faible coût de production qui permet de développer des applications ayant un unique cycle de vie. Cependant, si le coût de fabrication des nœuds constituant ce type de réseaux est assez faible, ces nœuds sont aussi limités en capacité en termes de: rayon de transmission radio, bande passante, puissance de calcul, mémoire, énergie, etc. Ainsi, les applications qui visent l'utilisation des MWNs doivent être conçues avec une grande précaution, et plus spécialement la conception de la fonction de routage, vu que les communications radio constituent la tâche la plus consommatrice d'énergie.Le but de cette thèse est d'analyser les différents défis et contraintes qui régissent la conception d'applications utilisant les MWNs. Ces contraintes se répartissent tout le long de la pile protocolaire. On trouve au niveau application des contraintes comme: la qualité de service, la tolérance aux pannes, le modèle de livraison de données au niveau application, etc. Au niveau réseau, on peut citer les problèmes de la dynamicité de la topologie réseau, la présence de trous, la mobilité, etc. Nos contributions dans cette thèse sont centrées sur l'optimisation de la fonction de routage en considérant les besoins de l'application et les contraintes du réseau. Premièrement, nous avons proposé un protocole de routage multi-chemin "en ligne" pour les applications orientées QoS utilisant des réseaux de capteurs multimédia. Ce protocole repose sur la construction de multiples chemins durant la transmission des paquets vers leur destination, c'est-à-dire sans découverte et construction des routes préalables. En permettant des transmissions parallèles, ce protocole améliore la transmission de bout-en-bout en maximisant la bande passante du chemin agrégé et en minimisant les délais. Ainsi, il permet de répondre aux exigences des applications orientées QoS.Deuxièmement, nous avons traité le problème du routage dans les réseaux mobiles tolérants aux délais. Nous avons commencé par étudier la connectivité intermittente entre les différents et nous avons extrait un modèle pour les contacts dans le but pouvoir prédire les future contacts entre les nœuds. En se basant sur ce modèle, nous avons proposé un protocole de routage, qui met à profit la position géographique des nœuds, leurs trajectoires, et la prédiction des futurs contacts dans le but d'améliorer les décisions de routage. Le protocole proposé permet la réduction des délais de bout-en-bout tout en utilisant d'une manière efficace les ressources limitées des nœuds que ce soit en termes de mémoire (pour le stockage des messages dans les files d'attentes) ou la puissance de calcul (pour l'exécution de l'algorithme de prédiction).Finalement, nous avons proposé un mécanisme de contrôle de la topologie avec un algorithme de routage des paquets pour les applications orientés évènement et qui utilisent des réseaux de capteurs sans fil statiques. Le contrôle de la topologie est réalisé à travers l'utilisation d'un algorithme distribué pour l'ordonnancement du cycle de service (sleep/awake). Les paramètres de l'algorithme proposé peuvent être réglés et ajustés en fonction de la taille du voisinage actif désiré (le nombre moyen de voisin actifs pour chaque nœud). Le mécanisme proposé assure un compromis entre le délai pour la notification d'un événement et la consommation d'énergie globale dans le réseau. / Great research efforts have been carried out in the field of challenged multihop wireless networks (MWNs). Thanks to the evolution of the Micro-Electro-Mechanical Systems (MEMS) technology and nanotechnologies, multihop wireless networks have been the solution of choice for a plethora of problems. The main advantage of these networks is their low manufacturing cost that permits one-time application lifecycle. However, if nodes are low-costly to produce, they are also less capable in terms of radio range, bandwidth, processing power, memory, energy, etc. Thus, applications need to be carefully designed and especially the routing task because radio communication is the most energy-consuming functionality and energy is the main issue for challenged multihop wireless networks.The aim of this thesis is to analyse the different challenges that govern the design of challenged multihop wireless networks such as applications challenges in terms of quality of service (QoS), fault-tolerance, data delivery model, etc., but also networking challenges in terms of dynamic network topology, topology voids, etc. Our contributions in this thesis focus on the optimization of routing under different application requirements and network constraints. First, we propose an online multipath routing protocol for QoS-based applications using wireless multimedia sensor networks. The proposed protocol relies on the construction of multiple paths while transmitting data packets to their destination, i.e. without prior topology discovery and path establishment. This protocol achieves parallel transmissions and enhances the end-to-end transmission by maximizing path bandwidth and minimizing the delays, and thus meets the requirements of QoS-based applications. Second, we tackle the problem of routing in mobile delay-tolerant networks by studying the intermittent connectivity of nodes and deriving a contact model in order to forecast future nodes' contacts. Based upon this contact model, we propose a routing protocol that makes use of nodes' locations, nodes' trajectories, and inter-node contact prediction in order to perform forwarding decisions. The proposed routing protocol achieves low end-to-end delays while using efficiently constrained nodes' resources in terms of memory (packet queue occupancy) and processing power (forecasting algorithm). Finally, we present a topology control mechanism along a packet forwarding algorithm for event-driven applications using stationary wireless sensor networks. Topology control is achieved by using a distributed duty-cycle scheduling algorithm. Algorithm parameters can be tuned according to the desired node's awake neighbourhood size. The proposed topology control mechanism ensures trade-off between event-reporting delay and energy consumption.
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Estudo dos grânulos de lipofucsina e das sinapses do córtex temporal durante o envelhecimento / Study of lipofuscin granules and synapses in the temporal cortex during aging.Merlo, Suélen 14 April 2011 (has links)
Alterações morfológicas e funcionais ocorrem durante o envelhecimento, período da vida com maior incidência de doenças neurodegenerativas. No presente trabalho acompanhou-se a evolução dos grânulos de lipofucsina durante o envelhecimento para investigar alterações sinápticas, assim como proteínas associadas com doenças neurodegenerativas (alfa-sinucleína) e com o sistema ubiquitina-proteossoma em indivíduos de diferentes idades. No córtex temporal humano e de ratos determinou-se, nos diferentes grupos etários, seguindo a área, o número e as características dos grânulos de lipofucsina, o número de sinapses excitatórias, inibitórias e elétricas, os locais de contatos pós-sinápticos, o número de vesículas sinápticas por terminal e a expressão das proteínas alfa-sinucleína e ubiquitina. Amostras de córtex temporal humano de indivíduos com diferentes idades (20 - 28, 37 - 41 e 50 - 55 anos) foram coletadas de pacientes com epilepsia submetidos à lobectomia do lobo temporal. Amostras de ratos de 2, 6, 10 e 12 meses também foram coletadas. Foram utilizadas técnicas de microscopia de luz, eletrônica, confocal e western blots. Os dados obtidos de grânulos de lipofucsina são consistentes com outros estudos que observaram aumento dessa estrutura em mamíferos de maior idade. No entanto, os grânulos parecem crescer em volume, mas não em número, com aumento considerável da fração elétron lúcida (lipídica). Não houve diferença na expressão das proteínas alfa-sinucleína e ubiquitina entre os grupos das idades estudadas. A densidade sináptica foi similar entre os grupos experimentais, assim como o local de contato pós-sináptico. O aumento de vesículas elétron densas em sinapses inibitórias deve estar associado à demanda de neurotransmissores catecolaminérgicos. Estes resultados não expressam totalmente o processo de envelhecimento, pois as faixas etárias de humanos e ratos correspondem a uma idade ainda jovem. A coleta de material humano mais idoso foi impossibilitada pela faixa etária dos doentes submetidos à lobectomia. Os ratos do biotério da FMRP, não sobrevivem mais do que 12 meses em no nosso ambiente, incluindo manutenção dos animais isolados em racks. / Morphological and functional changes occur during the aging, period of life with increased incidence of neurodegenerative diseases. Following the evolution of the lipofuscin granules along three periods of life in humans and rats, the present work investigated synaptic changes, as well as proteins associated with neurodegenerative diseases (alpha-synuclein) and the ubiquitin-proteossoma system in individuals of different ages. The objectives of the study were to analyze the temporal cortex of humans and rats: the number of excitatory, inhibitory, and electric synapses, the site of postsynaptic contacts, the number of synaptic vesicles per terminal, and the expression of the proteins alpha-synuclein and ubiquitin following the size and features of the lipofuscin granules. Samples of temporal cortex of human subjects with different ages (20-28, 37-41 and 50-55 years) were collected from patients with epilepsy who underwent temporal lobectomy. Samples from rats of 2, 6, 10 and 12 months were also collected. Light, confocal, and electron microscopy, and western blots techniques were used as procedures. The data obtained on lipofuscin granules were coincident with other studies that observed a higher area occupied by this structure in older mammals. However, the granules seem to grow in volume, but not in number, with considerable increase of the electron lucid fraction (lipidic). There was no difference in the alpha-synuclein and ubiquitin expressions between the experimental groups. The synaptic densities were similar between the groups, as well as the postsynaptic contacts. Increase of the electron dense vesicles in inhibitory synapses, appeared to be associated with the demand of catecholamines. These results do not express totally the aging process, because the range of age used in humans, and rats belong to a young age. The human samples from older ages was difficult because, in general, of the age of the patients submitted to lobotomy. The rats of the FMRP bioterium do not survived more that 12 months in our environment, even in controlled conditions.
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