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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.
41

The Thermal Evolution of the Ouachita Orogen, Arkansas and Oklahoma from Quartz-Calcite Thermometry and Fluid Inclusion Thermobarometry

Piper, Jennifer 2011 December 1900 (has links)
To understand the fluid temperature and pressure during the Ouachita orogeny, we used isotopic analysis of syntectonic veins and adjacent host material, quartz-calcite oxygen isotope thermometry and fluid inclusion analysis. The veins were at or near isotopic equilibrium with their host rocks; neither the host nor veins has been isotopically reset. The average isotopic variation in (delta18)O between vein and host is 2.4 plus/minus 1.7% and 0.7 plus/minus 1.7% for quartz and calcite, respectively. The temperature of vein formation from quartz-calcite oxygen isotope thermometry is about 210-430 degrees C. Although this is a large range, the temperature does not vary systematically in the exposed Ordovician through Mississippian rocks. The lack of isotopic difference between host and vein suggests that the host oxygen determined that of the veins. This in turn suggests that the fluid in the rocks did not change regionally. The vitrinite reflectance/temperature of the host rocks increases with restored stratigraphic depth more than that calculated with the quartz-calcite thermometer in veins. Fluid inclusion analysis in vein quartz constrains homogenization temperatures to be from 106-285 degrees C. Isochores from fluid inclusion analyses were constrained using quartz-calcite thermometry and vitrinite reflectance temperatures to calculate vein formation pressures of 0.3?4.7 kbars. These pressures correspond to vein formation depths up to 19 km, assuming an unduplicated stratigraphic section. Using burial curves and a reasonable range of geothermal gradients, vein formation ages are between 300 to 315 Ma, i.e., Early to Middle Pennsylvanian.
42

Quantifying Vein Patterns in Growing Leaves

Assaf, Rebecca 16 May 2011 (has links)
How patterns arise from an apparently uniform group of cells is one of the classical problems in developmental biology. The mechanism is complicated by the fact that patterning occurs on a growing medium. Therefore, changes in an organism’s size and shape affect the patterning processes. In turn, patterning itself may affect growth. This interaction between growth and patterning leads to the generation of complex shapes and structures from simpler ones. Studying such interactions requires the possibility to monitor both processes in vivo. To this end, we developed a new technique to monitor and quantify vein patterning in a growing leaf over time using the leaves of Arabidopsis thaliana as a model system. We used a transgenic line with fluorescent markers associated with the venation. Individual leaves are followed in many samples in vivo through time-lapse imaging. Custom-made software allowed us to extract the leaf surface and vein pattern from images of each leaf at each time point. Then average spatial maps from multiple samples that were generated revealed spatio-temporal gradients. Our quantitative description of wild type vein patterns during leaf development revealed that there is no constant size at which a part of tissue enclosed by vasculature will become irrigated by a new vein. Instead, it seemed that vein formation depends on the growth rate of the tissue. This is the first time that vein patterning in growing leaves was quantified. The techniques developed will later be used to explore the interaction between growth and patterning through a variety of approaches, including mutant analysis, pharmacological treatments and variation of environmental conditions.
43

Hyaluronan and the receptor CD 44 in the heart and vessels : a study in normal and pathological conditions /

Hellström, Martin, January 2007 (has links)
Diss. (sammanfattning) Umeå : Univ., 2007. / Härtill 5 uppsatser.
44

Depth and size limits for the visibility of veins using the veinviewer imaging system

Ganesh, Soujanya, January 2007 (has links) (PDF)
Thesis (M.S.)--University of Tennessee Health Science Center, 2007. / Title from title page screen (viewed on July 30, 2008). Research advisor: Jack A. Buchanan, M.D. Document formatted into pages (xii, 103 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 78-80).
45

The role of lymphaticovenous anastomoses in the treatment of postmastectomy oedema

Nieuborg, Leendert, January 1982 (has links)
Thesis (doctoral)--Universiteit van Amsterdam, 1982. / Vita. "Stellingen" (3 p. inserted) and summary in Dutch. Includes bibliographical references (p. 99-103).
46

The role of lymphaticovenous anastomoses in the treatment of postmastectomy oedema

Nieuborg, Leendert, January 1982 (has links)
Thesis (doctoral)--Universiteit van Amsterdam, 1982. / Vita. "Stellingen" (3 p. inserted) and summary in Dutch. Includes bibliographical references (p. 99-103).
47

Estudo da técnica de venografia dos dígotos de vacas

Loureiro, Marcos Gomes [UNESP] 19 December 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-19Bitstream added on 2014-06-13T21:02:15Z : No. of bitstreams: 1 000740527.pdf: 2750453 bytes, checksum: 84b108cb780a8a07dcbb67e643bf2540 (MD5) / Em bovinos a venografia retrógrada podal é pouco descrita, quando comparada com a espécie equina. O objetivo deste estudo foi descrever a técnica de venografia retrógrada podal em vacas, comparando os acessos da veia digital dorsal comum III com a digital comum II ou IV, nos membros torácicos e pélvicos mediante a administração de dois diferentes volumes de contraste. Foram utilizados 53 membros torácicos e pélvicos de 14 vacas, contidas em decúbito lateral no tronco com o torniquete de borracha posicionado a 5 cm do paradígito. Administrou-se 10 mL do diatrizoato de meglumine em 24 membros (grupo 1), sendo 13 na veia digital dorsal comum III pelo acesso 1 (A1) e 11 na digital II ou IV no acesso 2 (A2). No grupo 2, administrou-se 20 mL em 29 membros, sendo 15 pelo A1 e 19 no A2. Após a administração do contraste, as radiografias foram repetidas a cada 20 segundos até 120 segundos, na projeção dorso palmar/plantar 0°. O grau de preenchimento vascular foi maior no grupo 2, independente do acesso venoso, do membro ou momento. Não houve diferença significativa no grau de radiopacidade das imagens radiográficas quando comparado o acesso venoso, momento e membro de ambos os grupos. Conclui-se que a administração de 20 ml de contraste apresentou melhor preenchimento e radiopacidade, não havendo diferença entre 20 e 120 segundos após a administração do contraste na qualidade radiográfica independente do acesso venoso / In cattle the foot retrograde venography is rarely described, compared with the equine species. The aim of this study was to describe the technique of retrograde venography foot in cows, comparing the approaches of the dorsal common digital vein III with the digital commons II or IV, thoracic and pelvic by administering two different volumes of contrast members. Were used fifty tree fore and hindlimbs of 14 cows, contained in the lateral position on the trunk with rubber tourniquet placed at 5 cm from paradígito were used. Was administered 10 mL of diatrizoate meglumine 24 members (group 1), 13 dorsal common digital vein III for access 1 (A1) and 11 digital II or IV access 2 (A2). In group 2 was administered 20 mL 29 members, 15 by 19 in A1 and A2. After contrast administration, the radiographs were repeated every 20 seconds until 120 seconds, back projection on the palmar/plantar 0°. The degree of vascular filling was greater in group 2, independent of venous access, member or moment. There was no significant difference in the degree of radiopacity of radiographic images when compared to the venous access, time and a member of both groups. We conclude that administration of 20 ml of contrast showed better filling and radiopacity, with no difference between 20 and 120 seconds after contrast administration in independent radiographic quality venous access
48

Variská fluida spodního paleozoika Barrandienu: případová studie ze Žákova lomu ve Velké Chuchli / Variscan fluids of the Barrandian Lower Paleozoic: case study from the Žák's quarry at Velká Chuchle

Stárková, Petra January 2016 (has links)
Hydrothermal veins in the Paleozoic of the Barrrandian testify for fluid migration during diagenesis and/or epigenesis. A more detailed mineralogical and geochemical research of these veins has started since the end of the 20th century. The subject of a research included in this thesis is determination of conditions of formation of syntectonic calcite and quartz-calcite veins in the lokality called Žák's quarry in Velká Chuchle. This thesis is based on field determination of succession of hydrothermal veins and laboratory study of fluid inclusions in minerals as a basic tool for determination of temperatures during formation of veins. In total, there were distinguished four types/generations of calcite and quartz-calcite veins in Žák's quarry (from oldest to youngest): 1) veins of ,,beef calcite", 2) veins with flat crystals of smoky quartz located in joints perpendicular to bedding, 3) shear veins with calcite located in the big fold, 4) a big calcite vein with tectonic striae spatially bound to significant local fault. Veins have thickness aproximatelly from 1 mm to about 15 cm. By the way, veins of ,,beef calcite" are characteristic by orientation of prolonged grains of calcite in the direction orthogonal towards to the plane of vein. The microscopic study of fluid inclusions revealed presence of...
49

Quantifying Vein Patterns in Growing Leaves

Assaf, Rebecca January 2011 (has links)
How patterns arise from an apparently uniform group of cells is one of the classical problems in developmental biology. The mechanism is complicated by the fact that patterning occurs on a growing medium. Therefore, changes in an organism’s size and shape affect the patterning processes. In turn, patterning itself may affect growth. This interaction between growth and patterning leads to the generation of complex shapes and structures from simpler ones. Studying such interactions requires the possibility to monitor both processes in vivo. To this end, we developed a new technique to monitor and quantify vein patterning in a growing leaf over time using the leaves of Arabidopsis thaliana as a model system. We used a transgenic line with fluorescent markers associated with the venation. Individual leaves are followed in many samples in vivo through time-lapse imaging. Custom-made software allowed us to extract the leaf surface and vein pattern from images of each leaf at each time point. Then average spatial maps from multiple samples that were generated revealed spatio-temporal gradients. Our quantitative description of wild type vein patterns during leaf development revealed that there is no constant size at which a part of tissue enclosed by vasculature will become irrigated by a new vein. Instead, it seemed that vein formation depends on the growth rate of the tissue. This is the first time that vein patterning in growing leaves was quantified. The techniques developed will later be used to explore the interaction between growth and patterning through a variety of approaches, including mutant analysis, pharmacological treatments and variation of environmental conditions.
50

Anomalies structurelles et fonctionnelles de l'arbre vasculaire pulmonaire au cours de l'HTAP : de la morphologie à l'analyse moléculaire. / Structural and functional changes of the arterial bed in Pulmonary Arterial Hypertension : pathobiological insights through correlation of molecular and morphologic features.

Ghigna, Maria 04 October 2016 (has links)
La physiopathologie des hypertensions pulmonaires (HP) reste encore imparfaitement comprise. Plusieurs mécanismes interviennent dans le développement et la progression du remodelage vasculaire pulmonaire. Les perturbations de communications intercellulaires et l’activation de certaines voies de signalisation sont des phénomènes importants contribuant à l’accumulation excessive de cellules au sein de la paroi des petites artères pulmonaires.Par ailleurs, des facteurs génétiques et environnementaux peuvent prédisposer ou faciliter la progression de ce remodelage vasculaire.L’existence de modifications des micro-vaisseaux pulmonaires pré- et post-capillaires et bronchiques dans l’hypertensionn pulmonaire post-embolique et l’hypertension artérielle pulmonaire represente un aspect nouveau de ces deux maladies et permettra d’améliorer sur le long terme la prise en charge de ces patients. Ces altérations vasculaires sont aussi présentes dans deux modèles animaux d’étude d’hypertension pulmonaire, validant la pertinence d’approfondir nos connaissances au travers de ces outils expérimentaux. / The pathophysiology of pulmonary hypertension (PH) remains unclear. Différent mechanisms are involved in the vascular remodeling in PH. The disruption of cellular interactions and the activation of specific signalling pathways contribute to the development and progression of the structural changes in small pulmonary arteries. Moreover, environmental and genetic factors may predispose to this vascular disease.The alterations of pulmonary micro-vessels and of bronchial circulation in chronic thromboembolic disease and in pulmonary arterial hypertension represent a new finding in such diseases, with potential implications in the managment of patients. Pulmonary microvascular changes and bronchial circulation remodeling are also idenfied in selected animal models of PH.

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