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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.
321

Effects of ice application on nitric oxide levels following rhythmic handgrip contractions

Marvar, Paul J. January 2004 (has links)
Thesis (M.S. Ed.)--Northern Illinois University, 2001. / Includes bibliographical references (leaves [33]-45).
322

Rezente submarine Barytbildung im Derugin-Becken (Ochotskisches Meer) geochemische Prozesse an aktiven Fluidaustrittsstellen /

Bollwerk, Sandra Marianne. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2002--Kiel.
323

The relationship of the pneumococcus to acute infections of the upper respiratory tract in man; the gram-negative cocci in "colds" and influenza ...

Gordon, John Everett. January 1900 (has links)
Thesis (Ph. D.)--University of Chicago, 1921. / "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." "Reprinted from the Journal of infectious diseases, vol. 29, no. 5." LC copy replaced by microfilm. Also available on the Internet.
324

CIRP Expression on Growth and Productivity of CHO Cells

Tan, Hong-Kiat, Yap, Miranda G.S., Wang, Daniel I.C. 01 1900 (has links)
Mammalian cell culture is typically operated at the physiological temperature of 37°C. Low temperature cell culture at 30-33°C, in particular for CHO cells, increased the specific productivity of many recombinant proteins amongst many other benefits. However, the cell density is lower, thus reducing the total protein yield. Of the 17 mammalian cold-stress genes reported to be up- or down-regulated at low temperature, CIRP shows potential as a gene target for improving recombinant protein production, as its expression levels were reported to affect both growth and specific productivity. In this study, it was shown that over-expression of the cold-stress gene CIRP did not cause growth arrest in CHO cells, in contrast to previous reports. However, over-expression of CIRP successfully improved the specific productivity and total yield of a recombinant interferon-γ CHO cell-line at 37°C by 25%. / Singapore-MIT Alliance (SMA)
325

Contested innocence images of the child in the Cold War /

Peacock, Margaret Elizabeth. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
326

Analysis of the cold gas spraying process and determination of selected properties of metallic coatings on polymers / L'analyse du processus de la projection à froid et la détermination de certaines propriétés des revêtements projetés de poudres métalliques sur les substrats en polymères / Analiza procesu natryskiwania zimnym gazem oraz określenie wybranych właściwości powłok metalowych na polimerach

Malachowska, Aleksandra 22 March 2016 (has links)
Le but de cette thèse de doctorat état d’analyser la possibilité de la métallisation des couches des polymères à l’aide de la méthode de pulvérisation avec du gaz froid sous une basse pression. Deux substrats thermoplastiques et cinq poudres métalliques ont été étudiés. Les substrats étaient le polycarbonate amorphe et le polyamide 6 semicristalin. La poudre était : sphérique, globulaire, dendrique cuivre, aluminium et étain. Le processus de déposition s'est avéré beaucoup plus complexe que dans le cas du substrat de métal. Les problèmes étaient, entre autres : faible dureté du substrat, comportement fragile dans les basses températures, l'amollissement thermique dans des températures très basses. Le travail a commencé avec un calcul de la vitesse dans une basse pression du processus de pulvérisation a froid. La vitesse calculée pour toutes les poudres sauf l'étain étaient au-dessous de la vitesse critique pour les paramètres acceptables en ce qui concerne la déposition des polymères. Les premières épreuves ont confirmé que la déformation des particules de poudre n'était pas suffisante. Dans le cas de cuivre, il était impossible d'obtenir le revêtement. En plus, la force de liaison était très faible - les revêtements étaient delaminés spontanément. Deux mesures ont été entreprises pour améliorer les résultats : réduire la vitesse critique de la poudre et insérer des couches intermédiaires. Avec ces deux moyens, il a été possible d'obtenir les revêtements en cuivre et alluminium sur PA6 et PC. En s'appuyant sur l'étude, des conditions optimales pour la déposition de revêtement ont été choisies pour la caractérisation. La caractérisation des revêtements a inclu : l'analyse structurelle avec le microscope à la lumière et électronique à balayage, mesure d'adhésion, mesures du module d'Young, résistivité électrique, mesures de micro-dureté, mesures de coefficient de dilatation thermique, mesures de contenu d'oxygène et la simulation FEM pour étudier le mécanisme de déposition. / The aim of this Phd thesis was to analyze the possibility of metallization of polymers surface using a Low-Pressure Cold Gas spraying method. Two polymers substrate: polyamide 6 (Pa 6) and polycarbonate (PC) were investigated. The coatings were deposited using: tin, aluminium and copper powders. Within the framework of this work powders particles velocity and temperature was calculated during spraying process. The obtained particle velocity was compared to the critical velocity to select initial spraying conditions. Direct spraying on polymers substrate brought acceptable properties only for tin powder. Aluminium coatings delaminated spontaneously after spraying process. In case of copper powder deposition of continuous layer was impossible. Next, the influence of powder morphology, heat treatment of the feedstock material and the use of interlayers on the deposition process was investigated. Consequently, aluminium and copper coatings were obtained on both polymers. For a set of received coatings (Sn, Al, Cu) microstructure was observed and the results of adhesion, resistivity, micro-hardness, Young's modulus, and oxygen content in powders and coatings measurements were given. The bonding mechanism of the powder particles with substrate material was investigated using simulation of impact of copper and tin particle on polyamide substrate in Abaqus program. The simulation results were compared to experimental results. The dissertation was summed up with conclusion and possibilities of further research. / Celem niniejszej rozprawy doktorskiej była analiza możliwości metalizacji powierzchni tworzyw sztucznych za pomocą metody niskociśnieniowego natryskiwania zimnym gazem (z ang. Low-Pressure Cold Spraying – LPCS). Jako podłoże zastosowano dwa polimery: poliamid 6 (PA 6) i poliwęglan (PC). Powłoki zostały wykonane z użyciem proszków: cyny, aluminium i miedzi. W ramach pracy obliczono prędkość oraz temperatura cząstek proszku podczas procesu natryskiwania. Na podstawie porównania otrzymanych wyników prędkości cząstek proszku do prędkości krytycznej dobrano wstępne parametry procesu. W przypadku bezpośredniego natryskiwania na tworzywo jedynie powłoki cynowe charakteryzowały się akceptowalnym właściwościami. Powłoki aluminiowe miały tendencje do samoistnego odspajania. W przypadku prób nanoszenia proszku miedzi nie udało się uzyskać ciągłej warstwy. W dalszej kolejności zbadano wpływ morfologii i obróbki cieplnej proszku oraz zastosowania międzywarstw na proces formowania powłoki, co pozwoliło na uzyskanie powłok aluminiowych i miedzianych na powierzchni obydwu tworzyw sztucznych.Dla kompletu uzyskanych powłok (Sn, Al, Cu) przedstawiono zdjęcia mikrostruktury oraz wyniki pomiarów wyniki pomiarów przyczepności, rezystywności, mikrotwardości,modułu Younga, zawartości tlenu w proszku i powłoce. Mechanizm wiązania cząstek proszku z materiałem podłoża przeanalizowano za pomocą symulacji uderzenia cząstek miedzi i cyny w podłoże poliamidowe w programie Abaqus. Wyniki z symulacji zostały porównane do rezultatów eksperymentalnych. Całość pracy podsumowano wnioskami oraz przedstawiono możliwości dalszych badań.
327

British domestic security policy and communist subversion, 1945-1964

Styles, William January 2017 (has links)
This thesis is concerned with an analysis of British governmental attitudes and responses to communism in the United Kingdom during the early years of the Cold War, from the election of the Attlee government in July 1945 up until the election of the Wilson government in October 1964. Until recently the topic has been difficult to assess accurately, due to the scarcity of available original source material. However, as a result of multiple declassifications of both Cabinet Office and Security Service files over the past five years it is now possible to analyse the subject in greater depth and detail than had been previously feasible. The work is predominantly concerned with four key areas: firstly, why domestic communism continued to be viewed as a significant threat by successive governments – even despite both the ideology’s relatively limited popular support amongst the general public and Whitehall’s realisation that the Communist Party of Great Britain presented little by way of a direct challenge to British political stability. Secondly, how Whitehall’s understanding of the nature and severity of the threat posed by British communism developed between the late 1940s and early ‘60s, from a problem considered mainly of importance only to civil service security practices to one which directly impacted upon the conduct of educational policy and labour relations. Thirdly, how official counter-subversion methods were formulated and enacted over the period – from remarkably limited beginnings as small-scale vetting reform to a wide-ranging program of surveillance and counter-propaganda by the early 1960s. And finally, whether such responses can be judged as proportional with the benefit of historical hindsight, or if the British government’s conduct should be regarded as an egregious example of reactionary censorship and infringement of civil liberties in the modern era.
328

Revêtement de cuivre par projection à froid basse pression sur substrats d'aluminium texturés et composites PEEK/Carbone. Approche expérimentale et numérique. : approche expérimentale et numérique / Low Pressure Cold Sprayed copper coatings on laser textured aluminium substrates and PEEK/Carbon Fiber composite material : experimental and numerical considerations

Gillet, Vincent 17 January 2018 (has links)
Le Cold Spray Basse Pression est un procédé de projection thermique émergeant de plus en plus apprécié par les industriels pour sa simplicité, son faible coût et sa polyvalence. Pour améliorer encore les caractéristiques des dépôts, des substrats en aluminium ont été préalablement texturés par laser, sous la forme de trous de dimensions variables répartis selon un motif régulier, avant d’être revêtus de cuivre. Une optimisation géométrique de la surface a alors permis d’augmenter l’adhérence de dépôts Cu/Al2O3 de +81% par rapport à un substrat brut. Ces résultats sont analysés, notamment à l’aide d’un modèle mathématique développé durant la thèse permettant de calculer l’augmentation de surface induite par la texturation. De plus, une caractérisation des contraintes résiduelles par DRX à travers l’épaisseur a mis en évidence l’uniformité des contraintes en compression dans le dépôt. Dans un second temps, des dépôts de cuivre ont été réalisés sur des substrats en composite PEEK/Carbone. La nécessité d’avoir une couche de matrice organique à la surface du composite a été mise en évidence afin d’éviter une érosion du substrat et permettre la construction du dépôt. Une stratégie de projection basée sur une variation de la granulométrie des poudres en cours de projection a également été développée afin de réduire le taux de porosité et obtenir des dépôts conducteurs électriquement. En complément de ce volet expérimental, un modèle numérique 3D en dynamique a été développé sur Abaqus/Explicit. Il permet d’étudier l’influence des paramètres de projection et de l’état de surface du substrat sur la déformation des particules lors de l’impact et les contraintes résiduelles induites. / Low Pressure Cold Spray is an emerging thermal spraying process increasingly appreciated in the industry for its simplicity, low cost and versatility. In order to enhance coatings characteristics, aluminum substrates were laser-textured with holes of varying dimensions distributed in a regular pattern before being coated with copper. An optimization of the holes dimensions led to an increase of the adhesion for Cu/Al2O3 coatings by +81% compared to a raw substrate. These results were analyzed using a mathematical model developed during the thesis allowing to calculate the surface increase induced by the laser texturing. Moreover a characterization of the residual stresses by XRD through the thickness revealed the uniformity of compressive stresses in the deposit. In a second time copper deposits were made on PEEK/Carbon composites. The need to have an organic matrix layer on the composite surface has been highlighted in order to avoid substrate erosion and allow the coating construction. A spraying strategy based on a variation of the powders granulometry being sprayed has therefore been developed in order to reduce the porosity and obtain electrically conductive coatings. In addition to this experimental aspect, a 3D dynamic model has been developed on Abaqus/Explicit. This model allowed to study the influence of the projection parameters and the substrate surface state on the particles deformation during the impact and the induced residual stresses.
329

Beat Women: The Thunder Before the Storm-An Analysis of Feminism's Bridge Generation

Miller, Jeanette Leigh 01 August 2014 (has links)
The 1950s saw the height of the Beat literature movement. Within this movement moved a cohort of women who helped revolutionize gender relations in the early Cold War era, leading to the emergence of the women's liberation movement of the 1960s and 1970s. By questioning social gender norms and harnessing their artistic, sexual, and economic autonomy, Beat women built lives of lived art outside proscribed social norms building the base for a new era in gender relations.
330

Reproductive Patterns of Cold-Seep Mussels in the Gulf of Mexico and Northwestern Atlantic

Plowman, Caitlin 06 September 2017 (has links)
Continuous or semi-continuous reproduction is the norm in deep-sea animals, with exceptions explained by seasonal pulses of surface-derived phytodetritus. Chemosynthesis-based ecosystems such as cold seeps have an independent nutritional supply and are often thought of as decoupled from surface productivity. This thesis explores reproductive patterns of four bathymodiolin mussel species from 14 cold seeps (320 to 3300 m depth) in the Gulf of Mexico (2014) and the northwestern Atlantic (2015). Using paraffin histology, I determined maturity stages for male and oocyte sizes for female mussels. All species at all sites reproduced periodically and synchronously, with geographic synchrony among sites. This suggests that mussels rely on a site-independent cue such as seasonal phytodetrital flux to synchronize reproduction, providing evidence for a stronger coupling between surface productivity and chemosynthesis-based fauna than previously expected. Mature oocytes were of similar size for all species at all depths, suggesting that egg size is phylogenetically constrained.

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