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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Retrieval of tropospheric temperature and composition profiles from infrared radiance measurements

Grippa, Manuela January 2000 (has links)
No description available.
2

Role of gonadal steroids in the mating behaviour of the ram Ovis aries L. /

D'Occhio, Michael J. January 1983 (has links) (PDF)
Thesis (Ph.D.)-- University of Adelaide, Dept. of Animal Sciences,1983. / Typescript (photocopy). Includes bibliographical references (leaves 198-259).
3

Origin and maintenance of genetic diversity in northern European sheep

Tapio, M. (Miika) 01 November 2006 (has links)
Abstract The Nordic and Baltic countries and North-western Russia have >20 old native sheep breeds. These together with recently synthesized breeds and local populations of international breeds make up the northern European sheep diversity. Changes in agriculture threaten to erode genetic diversity in sheep. Molecular genetic variation was assessed to understand genetic diversity in northern European sheep. Distribution of maternal lineages were studied based on mitochondrial control region variation in 76 sheep breeds in northern Europe and in a wide neighbouring area extending to the Caucasus and Central-Asia. Autosomal microsatellite variation was studied in 37 northern European breeds, and autosomal blood protein variation was studied in six Finnish and Russian breeds. Four distinct maternal lineages were observed in Eurasian sheep. Their distribution agrees with sheep expansion starting from the Near East. Two most common distinct lineages were recorded in northern Europe. Majority of northern sheep have the lineage, which predominates in other parts of Europe. Results suggest that the main maternal origin of northern sheep is in the south. However, rare "Asian" lineage was observed in several old northern European breeds. The rare type in the Nordic sheep is descendant to the type observed in the Middle Volga region, which suggest that some sheep were brought to northern Europe from the east. Microsatellites showed clustering of geographically neighbouring sheep, when breed locations are corrected for the recent transportations. The analysis separated long and short-tailed sheep, although this macroscale structure explains a small proportion of breed differences. Differentiation among the northern European breeds is stronger than typically observed in sheep. Many native breeds are less inbred than the local populations of the international breeds, but some rare breeds and subpopulations of divided unofficial strains were inbred. Some breeds require more careful maintenance due to recent population size reduction. Maintaining prolificacy in breeds such as the Finnsheep and the Romanov may require efficient avoidance of inbreeding. The breeds were ranked for conservation using simultaneously within-breed variation and breed divergence. Set of important breeds included seven rare old native breeds or strains which merit efficient conservation measures urgently.
4

Library support for historical and persistent data structures in non-volatile memories

Chatzistergiou, Andreas January 2016 (has links)
In the context of emerging non-volatile memory (NVM) where data structures can persist in-memory and are accessed through CPU loads and stores, we study how to efficiently manage data evolution. This is an extensively applied problem in both the scientific and business domains and is rapidly becoming an important component for a wider range of applications. We argue that the best way to achieve a smoother transition to the new programming model is to design a solution that is non-intrusive and generic i.e. not bound to a specific data model. We propose a novel library-level approach where the user can manage historical data directly from programming language code. This is achieved with a combination of two software layers: REWIND and VARIANT. At the bottom, lies REWIND (REcovery Write-Ahead System for In- Memory Non-Volatile Data Structures) which handles the low level specifics of NVM by dealing with write-ordering problems that arise in such context and allows recoverability of arbitrary data structures. Then, VARIANT (Versioning ARbItrary dAta structures in Non-volatile memory for Time-travel) focuses on versioning and time travel (moving between versions). We adopt a logging approach and we tightly integrate both systems for best performance by utilizing a common physical log of memory operations. With REWIND, we propose a novel recoverable log structure that permits atomic and durable appends and removals of log records. This is the keystone for building recoverable systems on top of NVM. Because latencies in recent NVM technologies such as Phase-change memory (PCM) are asymmetric, we propose novel techniques for reducing the write pressure of the recoverable log as well as mitigating the effect of synchronization control primitives such as memory fences (enhanced for NVM), i.e. barriers that enforce ordering and persistence to preceding instructions. We also propose different implementations for trading logging performance for rollback performance when this is appropriate. Finally, we revisit state-of-the-art recovery algorithms for the new context given the different latencies and synchronization control. Our results clearly indicate that current approaches for recoverability are ill-fitted for persisting data structures in the new context and it is possible to achieve low-overhead logging with customized mechanisms. Next, we focus on data evolution. We expose a simple API that allows versioning and time travel with minimal intrusiveness. We propose mechanisms for efficient and transparent cloning of Versionable data structures. This allows high concurrency since past images are returned as copies of the original data structure which remains intact. Then, we propose novel indexing techniques that significantly improve time travel performance as well as cloning with lazy schemes. We achieve a low overhead architecture by employing a mix of volatile and non-volatile data structures as well as hybrid structures that reside in both volatile and non-volatile memories. We perform an extensive evaluation of the proposed techniques and conclude that, in our context, by carefully mitigating the drawbacks of physical logging it is possible to create efficient systems for managing data evolution that are both data structure agnostic and non-intrusive.
5

Role of gonadal steroids in the mating behaviour of the ram Ovis aries L.

D'Occhio, Michael J. January 1982 (has links) (PDF)
Typescript (photocopy) Includes bibliographical references (leaves 198-259) The role of gonadal steroids in the mating behaviour of rams was investigated in both entire rams and castrated rams (wethers) treated with different steroids.
6

Role of gonadal steroids in the mating behaviour of the ram Ovis aries L. / by Michael J. D'Occhio

D'Occhio, Michael J. January 1983 (has links)
Typescript (photocopy) / Includes bibliographical references (leaves 198-259) / xvi, 259 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The role of gonadal steroids in the mating behaviour of rams was investigated in both entire rams and castrated rams (wethers) treated with different steroids. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences,1983
7

Role of gonadal steroids in the mating behaviour of the ram Ovis aries L. / by Michael J. D'Occhio

D'Occhio, Michael J. January 1983 (has links)
Typescript (photocopy) / Includes bibliographical references (leaves 198-259) / xvi, 259 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The role of gonadal steroids in the mating behaviour of rams was investigated in both entire rams and castrated rams (wethers) treated with different steroids. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences,1983
8

Bleats from the north : Evaluation of osteological methods with support of archaeogenetics to distinguish between sheep and goats / Bräkanden från Norden : Utvärdering av osteologisk metod med stöd av arkeogenetik för att särskiljamellan får och getter

Theorell, Hannes January 2014 (has links)
This study is an extension of the author's previous thesis (Theorell 2013) and focus on the analysed tibia, the humerus and the proximal and distal part of the radius of sheep bones from Gotland and goat bones from City of Falun. Methods for bone elements assessed in this study are compiled and evaluated by Zeder and Lapham (2010). The bones were then geneticallyspecies identified and the results were compared. Seven of thirteen criteria for both sheep and goat reached 100% of correct identification.Best performing criteria were on humerus and distal radius for both sheep and goats. The results for the complete bone assessments divided for the species showed best performance ongoats. Worst performing bone is the tibia. High performing criteria were found on all thetypes of bones used in this study which can be used to distinguish between sheep and goats. / Föreliggande studie är en utökning av författarens tidigare magisteruppsats (Theorell 2013) och fokuserar på att analysera skenben, överarmsben samt proximal och distal del av strålbenet från fårben från Gotland och getben från Falun. Metoder för benslagen som används i denna studie har samlats och utvärderats av Zeder och Lapham (2010). Efter osteologisk analys har benen genetiskt artidentifierats och resultaten från bägge analyser har jämförts. Sju av tretton kriterier för både får och getter visade 100% korrekt bedömning. Kriterier med bäst resultat fanns på överarmsben och distalt på strålben. Sett till bedömning av komplett benslag skilt mellan får och getter visade att metoderna presterade bäst på getter. Sämst resultat uppvisades på skenbenet. Generellt uppvisade samtliga benslag kriterier som är möjliga att använda för att särskilja mellan får och getter.
9

AnÃlise genÃmica das principais raÃas de ovinos brasileiras / Genomic analysis of the major brazilian sheep breeds

JoÃo Josà de Simoni Gouveia 29 April 2013 (has links)
nÃo hà / As raÃas de ovinos localmente adaptadas brasileiras, tambÃm conhecidas como nativas ou crioulas, descendem de animais trazidos durante o perÃodo colonial e, desde aquela Ãpoca, vÃm sendo submetidas a processos evolutivos sistemÃticos e nÃo sistemÃticos., o que resultou na formaÃÃo de genÃtipos altamente adaptados Ãs mais diversas condiÃÃes ambientais brasileiras. Embora estas raÃas nÃo possuam o mesmo potencial produtivo das raÃas exÃticas melhoradas, elas sÃo consideradas extremamente importantes devido Ãs relaÃÃes sociais e culturais que guardam com as populaÃÃes do campo. AlÃm disso, as raÃas localmente adaptadas possuem caracterÃsticas adaptativas importantÃssimas para a manutenÃÃo de sistemas produtivos tradicionais. A otimizaÃÃo da utilizaÃÃo dos recursos genÃticos naturalizados depende de um conhecimento profundo destas populaÃÃes e, portanto, a caracterizaÃÃo morfolÃgica, produtiva e molecular sÃo ferramentas imprescindÃveis para o sucesso da conservaÃÃo e utilizaÃÃo deste recurso genÃtico. Com base nisso, o objetivo desta tese foi aprofundar os estudos de caracterizaÃÃo molecular das principais raÃas de ovinos localmente adaptadas brasileiras: Crioula Lanada, Morada Nova e Santa InÃs. Assim, o capÃtulo I intitulado âIdentificaÃÃo de assinaturas de seleÃÃo em animais de produÃÃoâ consiste em uma revisÃo cujo objetivo à descrever os principais efeitos da seleÃÃo natural/artificial nos genomas das espÃcies de animais de produÃÃo, apresentar os principais mÃtodos de anÃlise de assinaturas de seleÃÃo e discutir os recentes avanÃos nesta Ãrea de estudo. Foram realizados dois estudos que resultaram nos capÃtulos II e III desta tese. O capÃtulo II, intitulado âIdentificaÃÃo de assinaturas de seleÃÃo em ovinos de raÃas localmente adaptadas brasileirasâ, teve como objetivo a identificaÃÃo e caracterizaÃÃo de regiÃes genÃmicas provÃveis de estar sob seleÃÃo nas trÃs principais raÃas brasileiras localmente adaptadas de ovinos e caracterizar estar regiÃes com a finalidade de identificar genes envolvidos com diferenÃas produtivas/adaptativas entre estas raÃas. A identificaÃÃo das regiÃes sujeitas à seleÃÃo foi feita com base em dois tipos de metodologia: diferenciaÃÃo entre populaÃÃes (FST) e desequilÃbrio de ligaÃÃo (iHS e Rsb). Foram identificados 78 genes candidatos envolvidos com funÃÃes como: resposta imune, desenvolvimento do sistema nervoso, percepÃÃo sensorial e desenvolvimento de pelos/lÃ. O capÃtulo III, intitulado: âIdentificaÃÃo de subestrutura de populaÃÃes em ovinos de raÃas localmente adaptadas brasileirasâ, teve como objetivos identificar e caracterizar a presenÃa de subestruturaÃÃo genÃtica dentro das trÃs principais raÃas brasileiras localmente adaptadas de ovinos. Foi observada, de uma forma geral, a presenÃa de diferenciaÃÃo genÃtica bastante considerÃvel ao comparar os rebanhos de cada raÃa analisada. AlÃm disso, tanto na raÃa Crioula Lanada quanto na raÃa Santa InÃs, pode ser observada a presenÃa de grupos bem distintos de indivÃduos, sugerindo a efetiva presenÃa de diferentes ecÃtipos/linhagens dentro destas raÃas. / The Brazilian locally adapted sheep breeds, also known as native and creole, are descendant from animals brought during the settlement period and, since then, are been subjected to evolutive (both systematic and non systematic) processes, what resulted in the formation of highly adapted genotypes to the diverse environmental Brazilian conditions. Although these breeds donât posses the same productive potential when compared with the exotic improved breeds, they are considered extremely important from a social and cultural point of view. Moreover, the locally adapted breeds are essential for the maintenance of traditional production systems. The optimization of the utilization of naturalized genetic resources depends on a deep knowledge of these populations, and then, the morphological, productive and molecular characterizations are essential to the success of conservation and utilization of these locally adapted genotypes. Therefore, the principal aim of this thesis was to deepen molecular the knowledge of the three main locally adapted Brazilian sheep breeds: Brazilian Creole, Morada Nova and Santa Ines. Thus, Chapter I entitled "Identification of selection signatures in livestock species" is a literature review that is proposed to describe the main effects of natural/artificial selection in the genomes of species of farm animals, present the main methods of signature selection analysis and discuss recent advances in this area of study. Two studies were conducted and resulted in the chapters II and III of this thesis. The chapter II, entitled âIdentification of selection signatures in brazilian locally adapted sheep breedsâ, aimed the identification and characterization of putative genomic regions that underwent selection and the identification of candidate genes related to productive/adaptative differences between these breeds. The identification of signatures of selection was performed through two approaches: population differentiation (FST) and linkage disequilibrium (iHS and Rsb). Seventy eight genes, related to functions as: immune response, nervous system development, sensorial perception and wool/hair development were identified. The chapter III, entitled âIdentification of population substructure in brazilian locally adapted sheep breedsâ, aimed the identification and characterization of of genetic substructure within the three main locally adapted Brazilian sheep breeds: Brazilian Creole, Morada Nova and Santa Ines. The level of genetic differentiation between herds of the same breeds was, in general, high. Both in the Brazilian Creole and in the Santa Ines breeds the presence of distinct groups on animals could be observed, what suggests the occurrence of different ecotypes/lineages within these breeds.
10

Déplacements collectifs auto-organisés : décision individuelle et transfert d'information / Self-organized collective movements : individual decision and information transfer

Toulet, Sylvain 13 November 2015 (has links)
Les déplacements collectifs se manifestent souvent de façon spectaculaire et intriguent tant les amateurs de la nature que les chercheurs. Comment émergent ces formes spectaculaires et comment la cohésion des groupes est elle assurée ? Si de nombreux travaux ont été consacrés à l'identification des règles permettant la cohésion dans les groupes en mouvement, plus rares sont ceux consacrés aux transitions entre les états d'arrêt et de déplacement. Cette thèse traite des mécanismes comportementaux impliqués dans les prises de décisions collectives et la dynamique de transition de tels évènements chez le mouton Merinos (Ovis aries). Nous proposons de nouvelles hypothèses sur la modulation des interactions entre individus par des effets spatiaux dans des groupes de grande taille. Nous proposons un modèle spatio-temporel reproduisant nos résultats expérimentaux sur les départs, les déplacements collectifs et les arrêts de groupes de taille croissante et permettant d'explorer les décisions collectives dans des conditions nouvelles. Les résultats expérimentaux et théoriques per- mettent d'améliorer la compréhension des mécanismes individuels à l'origine des décision collectives permettant de maintenir ou non la cohésion des groupes. / Collective movements often involve very spectacular displays that fascinate nature lovers and researchers. How do such amazing patterns appear and how group cohesion can be maintained ? If many studies were carried out to decipher the rules underlying cohesion for groups in movement, there is a lack of works adressing the transitions involved in collective movements : departures and stops. This thesis adresses the behavioural mechanisms involved in the collective decision-making processes oc- curing in such transitions in Merino sheep (Ovis aries) groups. We propose some new kinds of spatial hypotheses that can account for the way interactions between individuals are locally modulated in large groups where individuals cannot have an access to the global information of all individuals. We developed a novel spatiotemporal model of sheep collective motion that reproduces the experimental observations and allows to explore the outcomes of collective decisions in various conditions. The experimental and theoretical results increase the understanding of the individual mechanisms that produce collective decisions allowing to maintain group cohesion.

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