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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.
91

Constructing Families and Kinship through Donor Insemination: Discourses, Practices, Relationships

Hargreaves, Katrina Mary January 2001 (has links)
This thesis explores the complex web of social relations created by the use of donor insemination (DI) in Aotearoa/New Zealand. The experiences of pursuing parenthood and creating a family using this method of assisted conception are contextualised through attention to the practices of Donor Insemination Programmes and the discourses used by parents, their families and health professionals. Sociologists and other social scientists have drawn attention to the social and cultural consequences of the fragmentation of biological/genetic, gestational and social parenting that follows the use of third party gametes. This thesis explores the implications of these procreative arrangements for the meanings attached to cultural concepts such as 'kinship', 'family', and 'parenthood'. Variation in the way these families respond to issues associated with the use of donor sperm in the conception of a child is also highlighted. The thesis also explores the dominant discourse in the New Zealand context of children's 'right' to know their genetic origins, and how this is played out in the perceptions and actions of health professionals, parents of children conceived by DI and their kin. The research is exploratory and qualitative, drawing on semi-structured interviews with parents, grandparents, aunts and uncles of children conceived by DI, and with health professionals working in DI programmes. The inclusion of the perspectives of extended family members and health professionals constitutes a unique contribution to research on families with children conceived by DI. The secrecy, anonymity and confidentiality that have surrounded DI practices have long hindered the study of families with children conceived by DI. Despite a trend towards information-sharing in DI in New Zealand, the thesis shows that for these families, patterns of secrecy and disclosure are complex, variable and embedded in particular social and relational contexts.
92

Optimisation multiobjectif de la conception de joints tubulaires collés structuraux

Labbé, Steve January 2012 (has links)
Bien que certaines règles générales aient été déterminées pour la conception de joints tubulaires collés structuraux, aucune procédure systématique d'optimisation ne permet de déterminer la nature des configurations optimales ou les règles de conception du joint qui sont propres à l'application envisagée. Dans ce contexte, l'objectif principal de cette Thèse est d'élaborer une procédure d'optimisation multiobjectif qui permet d'identifier des configurations globalement optimisées de joints tubulaires collés à simple recouvrement soumis à différents types de chargements simples et à un chargement combiné. La procédure d'optimisation proposée se détaille en quatre étapes : 1) identifier les propriétés et loi de comportement des matériaux pour toutes les pièces qui forment le joint, 2 ) élaborer un modèle numérique d'analyse par éléments finis dans lequel toutes les dimensions géométriques constituent des paramètres dimensionnels, 3) réaliser une étude paramétrique pour identifier les paramètres qui influent de façon non négligeable les fonctions objectif impliquées dans les études d'optimisation subséquentes et 4) définir le problème d'optimisation, c'est-à-dire les variables d'optimisation, les fonctions objectif et les fonctions de contrainte, et exécuter les études d'optimisation. Cette procédure est employée pour réaliser un total de 17 études d'optimisation pour un joint tubulaire collé à simple recouvrement soumis à un chargement en traction pure (4), en torsion (2) et en flexion ordinaire (4) de même qu'à un chargement combiné (7). Les résultats de ces études fournissent de 20 à 229 configurations optimales et permettent de faire ressortir des règles de conception propres à l'application du joint. Les originalités apportées par cette Thèse ont principalement trait à la généralité de l'approche proposée pour la recherche d'une conception optimale d'un joint tubulaire collé. Plus spécifiquement, l'introduction de paramètres dimensionnels qui définissent l'entièreté du modèle du joint, la considération de plusieurs fonctions objectif conflictuelles dans l'optimisation sans accorder d'importance relative à chacune d'entre elles et l'application d'un chargement composé d'une combinaison de chargements simples (traction, torsion et flexion) constituent les éléments d'originalité de cette Thèse.
93

The influence of sex chromosomes on the outcome of human embryo development /

Raja, Kimenthra. January 2005 (has links)
Thesis (MMedSc)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
94

Mise en œuvre d'une procédure arborescente et d'une méthode de gradient réduit pour la CAO de cascades de colonnes de rectification.

Pibouleau, Luc, January 1900 (has links)
Th.--Génie chim.--Toulouse--I.N.P., 1985. N°: 92.
95

La conception informatique au-delà de l’entreprise : rôles des formes sociales émergentes et transverses aux organisations dans les milieux professionnels du génie logiciel / Designing softwares beyond firm boundaries : how social configurations emerging through organisations influence the professional world of software engineering.

Nelson, Mickaël 17 November 2010 (has links)
Dans un environnement professionnel à la fois complexe et fortement évolutif, lesconcepteurs de logiciels sont confrontés à la difficulté de devoir proposer des solutionstechnologiques innovantes, fiables et durables, alors que leurs référentiels sont peustabilisés. Dans ce contexte, des formes sociales transverses aux entreprises, comme lesréseaux professionnels, émergent et constituent de nouveaux points de repères pour lesinformaticiens. L’analyse comparative de quatre environnements distincts de conceptioninformatique met alors en évidence la multiplicité de la contribution de ces formes socialesdans le génie logiciel. Celles-ci constituent un support à l’activité opérationnelle, enpermettant de désenclaver les ressources, les compétences et les savoirs, et en stimulant lesapprentissages collectifs. Par ailleurs, l’inscription de l’oeuvre informatique dans ces formessociales donne corps à une activité professionnelle récente et dépourvue de véritablesrepères collectifs. La reconnaissance par les pairs est alors motivée par l’exercice de l’art ets’émancipe des contraintes externes à la technique. De plus, les relations qui se tissent entreles membres de ces communautés informelles posent les bases de revendicationsidentitaires préalables à la constitution d’un corps professionnel institué. Au demeurant, lerôle de ces formes sociales nouvelles soulève la question d’une évolution del’environnement professionnel, dans lequel le réseau constitue un mode d’organisation àpart entière. En particulier, le caractère informel des échanges qui prévaut dans cescommunautés traduit l’importance contemporaine du don et de la gratuité, même dans lesenvironnements fortement marchands. / In a professional environment characterized by its complexity and its evolution, softwaredesigners face the difficulties of having to propose innovative, reliable and durabletechnological solutions, despite a lack of steady systems of reference. In this context, socialconfigurations that remain transversal to firms (e.g. professional networks) have appeared,and henceforth represent new kinds of references for computer engineers. A comparativeanalysis of four specific environments of computer design underlines the multiplicity of thecontribution of these social configurations. Indeed, they support the operational activity,enabling to open up resources, skills and knowledge, and to improve collective learning.Moreover, inscribing a computer work is these social configurations reinforce a recentprofessional activity that lacks of deep collective references. Gratitude and acknowledgmentby peers are based on the practice of an art, and are emancipated from constraints thatremain external to technology. Relationships between members of these non formalcommunities are the basis of identity demands preliminary to the constitution of aninstituted profession. Furthermore, the role of these new social configurations questionsabout the evolution of the professional environment, which the network is a real andspecific configuration in. Especially, the informal character of exchanges shows thecontemporary importance of gift and free transactions, even in highly commercialenvironments.
96

Vyhodnocení reprodukčních ukazatelů ve vybraném stádě ovcí / The evalution of reproduction parametres in chosen herd of sheep

BENEŠOVÁ, Kristýna January 2009 (has links)
It has been observed the breed herd of Texel sheep in the foothills area of Orlické mountains in the year 2005-2008. The base of herd was consisted of 374 ewes, 575 lambs and 6 rams in total. These parametres of reproduction {--} conception, fertility, rearing, empty ewes, abortions, lambing, stillborn, death after born, were monitored at ewes. For the parametres of reproduction at ewes were found significant effects of ewe´s age and ram´s line.
97

Contribution à une théorie générale de la conception / Contribution to a general theory of design

Huysentruyt, Johnny 03 May 2013 (has links)
La thèse propose une contribution à une théorie générale de la conception visant à mettre en évidence des concepts communs à une grande variété de domaines.Après une analyse de l’état de la question, la thèse propose un cadre conceptuel ainsi qu'une analyse détaillée des concepts de projet, d’artefact, d’espace de conception, de processus de conception, d’organisation de conception et enfin, des activités cognitives du concepteur. Une étude de cas illustre les différents concepts. Les conclusions mettent en évidence l’apport et les limites de la contribution. / The thesis formulates a contribution to a general theory of design that aims at identifying concepts common to large number of design domains.After the analysis of the state of the art, the thesis formulates a conceptual framework as well as an in-depth analysis of following concepts: project, artefact, design space, design process, design organisation and the cognitive processes at the level of the designer. A case study provides an illustration of the different concepts. The conclusion highlights the added value and the limits of the contribution.
98

The influence of flush feeding with different nitrogen sources on ovulation and conception rates in Dohne-Merino ewes

Marais, Willem Jacobus 17 November 2011 (has links)
The aim of the present study was to determine if there is a difference in ovulation- and conception rates, in semiintensively managed Dohne-Merino ewes, flush fed with diets containing different nitrogen sources. Four different nitrogen sources were chosen due to the difference in dietary amino acid composition and cost. In order for a sheep farming enterprise to maximize profitability it is essential to optimize ovulation- and conception rates and to minimize lamb losses in order to increase weaning percentage and therefore profitability. However the cost of dietary supplementation is high and may increase production costs and minimize profitability. One hundred and fourty four (144) Dohne-Merino ewes (age between 14 to 85 months) were included in two dietary supplementation trials (autumn and summer) at the experimental farm of the University of Pretoria in Hatfield. The ewes were divided equally into two trial groups (n=72), with the first trial done in season 1 (started in May 2001, typical breeding season) and the second trial done in season 2 (started in November 2001, out of season; 2nd breeding season). During the day the ewes had ad-libitum access to graze on Festuca arundinaceace (Tall Fescue). In both trials the ewes (n=72) were randomly allocated into four dietary supplementation groups, each group receiving a dietary supplement with a different combination of nitrogen sources. The four dietary supplements were formulated on an iso-nitrogen basis, to eliminate the effect of protein level, and to emphasize the possible effect of protein quality (amino acid composition) on ovulation, conception and lambing rates. In both trials the total amount of crude protein intake per ewe was calculated at 256.40g/day, while the total daily allowance of digestible crude protein was calculated at 190g per ewe. The 256.40g crude protein intake per ewe per day is 2 times more than the threshold level of 125g per ewe per day. A minimum daily crude protein intake of 125g is needed for effective rumen functioning, and this together with the interconvertin of energy by the rumen indicates the complex nature of relating dietary differences to physiological responses. These values were kept the same for both the trials in season 1 and 2. The bulk of the 256.40g crude protein per day was obtained from grazing on the Festuca arundinaceace pasture. In season 1 the dietary supplement had to provide 40.00g of crude protein per day in order to get to a daily crude protein intake of 256.40g, while in season 2 the provision from the dietary supplement was calculated to be 37.45g of crude protein. The difference in the crude protein level, obtained from grazing of the Festuca arundinaceace between season 1 and 2 was due to pasture quality differences. The nitrogen sources used in the trials were urea, sunflower oilcake meal, cottonseed oilcake meal and a mixture of cottonseed oilcake meal and fishmeal. These dietary supplements were fed for a period of 9 days before mating; the weight of each ewe was recorded before the onset of the trial and again on the second day after mating to establish any live weight changes. Synchronization of the ewes was done with Chrono-gest grey sponges (40mg Fluorogestone acetate) from day one and was repeated from day 23. On day 12 each ewe were injected with 1.0ml prostaglandin F2α (Prosolvin,each milliliter containing 7.5mg Luprostiol). On day fourteen the sponges were removed and two days later all the ewes were checked for cyclic activity with the aid of six vasectomized rams. The six vasectomized rams were introduced to the whole laparoscopy group of 12 ewes, and every ewe that stood twice for mating were identified as cyclic. This practice continued for a period of 30 minutes in the morning and repeated for another 30 minutes in the afternoon up to day 18. The second round of sponges were inserted on day 23 and removed on day 37. Ewes were mated by means of hand mating with two different rams from day 39 to 42. A laparoscopy technique was used on day 45 of the trial to count the number of ovulation points (corpora lutea) on each ovarium of each ewe. The number of fetuses of each ewe was counted on day 90 after mating by means of ultrasound scanning and at birth the number of lambs born was also recorded. In both these trials dietary supplementation had no significant effect on ovulation, conception and lambing rates. However, looking at the Odds Ratio Analysis for the 144 ewes over the two breeding seasons, the different dietary supplements had a significant influence on the number of ovulation points (p<0.05). Compared to urea (dietary supplement 1), the fishmeal cottonseed oil cake mixture (dietary supplement 4) yielded the best results (1.306), followed by the cottonseed oil cake meal (dietary supplement 3) (1.298), and sunflower oil cake meal (dietary supplement 2) (1.050). The same Odds Ratio Analysis showed that the different dietary supplements had a significant effect on the number of lambs born (p<0.01). Compared to urea (dietary supplement 1), the fishmeal cottonseed oil cake mixture (dietary supplement 4) yielded better results (1.086), followed by urea (dietary supplement 1) (1.000), and sunflower oil cake meal (dietary supplement 2) (0.801) and lastly cottonseed oil cake meal (dietary supplement 3) (0.784). Breeding season (p<0.05) had a significant effect on the number of ovulation points but no difference was observed in terms of the number of lambs born. Age (p<0.01) had a significant effect on the number of ovulation points, the number of fetuses counted as well as the number of lambs born. Change in live weight (p<0.05) had a significant effect on the number of ovulation points per ewe but as with breeding season it had no significant effect on the number of lambs born. Birth status of a ewe (p<0.05), had a significant effect on the number of fetuses and the number of lambs born. The data of both the trials in season 1 and 2 suggests that under the conditions of the study with the odds ratio analyses that the four different dietary supplements had a significantly different effect compared to dietary supplement one on the number of ovulation points and the number of lambs born. However, factors like breeding season, age, change in live weight and birth status of the ewe also had a significant effect on ovulation and conception rates in Dohne-Merino ewes. / Dissertation (MSc(Agric))--University of Pretoria, 2011. / Animal and Wildlife Sciences / unrestricted
99

Stratégie d’optimisation des procédés d’assemblage et de fabrication dans le processus de réduction de poids du châssis d’un véhicule roadster

Mogenot, Yann January 2013 (has links)
Depuis plusieurs années, un intérêt grandissant pour les véhicules hybrides se fait sentir de la part des constructeurs. Que ce soit pour un modèle hybride, thermique et électrique, ou un modèle tout électrique, la masse importante d'un véhicule de type roadster va à l’encontre des objectifs de réduction de la consommation de carburant et d’augmentation de l’autonomie. Aussi, l’optimisation du châssis d'un roadster a été entreprise pour réduire la masse globale du véhicule. Le but de cette maîtrise est de juger de la viabilité mécanique et économique d’un châssis d’aluminium pour le roadster. Au changement de matériau vient s’ajouter la sélection d’un procédé d’assemblage pertinent. Les critères de choix seront la réduction de la masse du châssis après assemblage, le contrôle de son coût, l’assurance de sa bonne résistance mécanique, notamment en fatigue, et la rigidité de la structure. Plusieurs méthodologies ont été élaborées pour guider la conception des pièces en aluminium et permettre le choix d’un procédés d’assemblage pertinent. Appliquées au roadster, elles ont permis d’aboutir à la création de structures optimisées. Les méthodologies développées ont été formalisées pour être utilisables sur d’autres projets similaires.
100

Retrospective Analysis of the Effect Metformin Use and Lifestyle Modifications Have on Conception and Live Birth in Polycystic Ovary Syndrome

Smith, Kimberly M., Smorra, Amy January 2008 (has links)
Class of 2008 Abstract / Objectives: To assess the effect of metformin usage and lifestyle modifications in women with polycystic ovary syndrome (PCOS) in achieving conception and live birth. Methods: A retrospective chart review of patients at a southwest reproductive health center was performed. Patients given a diagnosis of PCOS, treated with metformin alone, with at least 12 weeks of outcome data were enrolled. Diagnostic, reproductive history, and baseline endocrine and metabolic data were collected. All available metformin use, menstrual cyclycity, ovulation, pregnancy, pregnancy outcome, and alternative treatment data were captured. Results: A total of 1250 charts were reviewed and 103 patients were enrolled. Pre-treatment, a significant relationship between BMI and HDL, triglycerides/HDL, and fasting glucose (P <0.001, 0.018, 0.016) was noted with leaner patients having better metabolic profiles. The pregnancy, miscarriage, and live birth rates with metformin treatment were 55.3 %, 18.2 %, and 35.0 % respectively. Patients (40/103) that did not conceive with metformin attempted alternative fertility treatment; 55% became pregnant and 30% had a live birth. One third of all patients experienced minor adverse events, primarily gastrointestinal in nature. Logistic regression analyses comparing responders to nonresponders did not identify any baseline patient characteristics useful as significant predictors of success with metformin treatment. Conclusions: For the population under study, metformin use and lifestyle modifications resulted in conception and live birth for as many as 35 % of patients. Contrary to recent publications, it appears that this method of fertility treatment remains a viable option to treat infertility in patients with polycystic ovary syndrome.

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