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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.
11

Anatomical and Morphological Responses of Cardiospermum Halicacabum L. (Balloon Vine), to Four Levels of Water Availability

Dempsey, Matthew Anthony 05 1900 (has links)
C. halicacabum (Sapindaceae) is an invasive plant that is considered a nuisance species in Texas riparian environments. Little is known of the tolerance of C. halicacabum to flooding and drought; however, this information may provide insight into the characteristics that contribute to C. halicacabum purported invasiveness. C. halicacabum seedlings (n = 92) were exposed to one of four levels of water availability (flooded, saturated, intermediate and dry) over six weeks under greenhouse conditions. Plant performance was affected by water availability; however, there was no effect on survivorship. Flooded and saturated plants exhibited morphological adaptations; producing adventitious roots, hypertrophy, and aerenchyma tissue. Morphological measures, anatomical responses, and patterns of biomass allocation all indicate that C. halicacabum is able to survive periodic inundation, perform in saturation, and establish and thrive on the drier end of a moisture gradient.
12

The behaviour of vascular smooth muscle cells under stress

Sturge, Justin January 1998 (has links)
No description available.
13

Investigating new Service System Solutions for High Altitude Balloons : Feasibility Study and Design Challenges

Peterson, Joakim January 2016 (has links)
The high altitude balloon operations at Esrange Space Center have been goingon since 1972, and about 550 launches have been performed. Their present service system for the high altitude balloons is about 18 years old. To be able to meet the requests from their customers, SSC have started the development of a new service system. A service system contains all features and technology required to perform a high altitude balloon mission. This system is separated from the payload. Important design aspects for the new service system have been investigated to be able to leave recommendations to SSC. These are frequency for the radio communication, modulation scheme for the communication link, prevention of corona discharge, and available computer systems to be used as on-board computers. These design aspects have been evaluated according to the requirements for the development project. Theory, articles, available standards and analyzes have been read and evaluated to reach a conclusion about these subjects. It was found that the best frequency bands are the 400MHz-band, downlink, and the 450MHz-band, uplink. The operation in these bands will be unmodified for many years, and the link suffers little loss. The 2.3GHz-band is interesting from an international perspective, and it is suggested that SSC work to get a band dedicated to aeronautical services in this band. The best modulation scheme for the service system is GMSK, as it has very good spectral eficiency. The corona discharge can only be prevented indirect by SSC, as the phenomena occurs within or between components, aspects which SSC can't control. Standardized methods for tests and specications lists was suggested to minimize the risk of a discharge. The best computer system is an in-house designed service system that have been used on sounding rockets. It fits the present requirements the best. It suggested that the Beaglebone Black should be implemented in basic systems, providing processing and storage via simple serial communication, as it is a very cost eficient solution.
14

Evaluation of the Aerodynamic Differences of a Balloon Shape and a Sphere Using Computational Fluid Dynamic Modeling in Fluent

Scholes, Daniel Burton 01 May 2011 (has links)
While tracking balloons for wind characterization, there was a question about the theoretical rise rate and corresponding coefficient of drag of a balloon shape as compared to a sphere. Since there are many studies published detailing the drag on spherical shapes, the question of whether or not a balloon can be treated as a sphere begged to be answered. In this study we apply Computational Fluid Dynamic (CFD) modeling to compare the aerodynamic behavior and drag of a sphere to that of a balloon as it moves through fluid at Reynolds numbers from 10,000 to 100,000. Fluent CFD models are created and used to estimate the coefficient of drag (Cd) vs. Reynolds number (Re) for a sphere and for a balloon shape. Details are given for the meshed model creation and the simulation methods. Sphere model results are compared to data provided in published literature. Sphere and balloon model results are compared to each other. The results of this study show that the drag on a balloon is not statistically different from a sphere. While there are differences in the flow characteristics over the two shapes, a spherical shape is a good approximation for a balloon shape.
15

Who designed your house? : a technological and cultural history of conventional wood construction, 1790-1880 /

Cavanagh, Edwin H. January 2002 (has links)
Thesis (Ph. D.)--Lehigh University, 2003. / Includes vita. Includes bibliographical references (leaves 320-339).
16

[Alpha]8[beta]1 integrin and vascular injury : role of [alpha]8[beta]1 integrin in restenosis after balloon injury

Zargham, Ramin. January 2007 (has links)
Restenosis is the major cause of the failure of reconstruction methods to restore the blood flow in atherosclerotic arteries. Restenosis results from neointima formation and consequent constrictive remodelling. Vascular smooth muscle cell (VSMC) migration from the tunica media toward the intima is crucial in neointima genesis. The prerequisite for VSMC migratory activity is the modulation from the differentiated (contractile) to the de-differentiated (noncontractile) phenotype. VSMC phenotype change is associated with the altered expression of integrins. alpha8beta1 integrin is upregulated in cell types with contractile properties, including myofibroblasts and mesangial kidney cells. It is one of the integrins that is intensely expressed in mature VSMCs. alpha8beta1 integrin expression during vascular injury and its role in VSMC function have not been studied so far. / In this work, a rat model of carotid angioplasty was used to mimic vascular injury in humans. alpha8beta1 integrin was downregulated in the tunica media concomitantly with loss of the contractile phenotype. In vitro study revealed that it is a differentiation marker of VSMCs. To test the functional significance of the association between alpha8 integrin and the VSMC phenotype, short interference RNA was deployed to silence the alpha8 integrin gene. alpha8 integrin gene silencing heightened VSMC migratory activity as well as modulation of the VSMC phenotype in favour of the noncontractile state. In addition, alpha8 integrin overexpression induced re-differentiation of VSMCs and attenuated their migratory activity. It is, therefore, suggested that alpha8 integrin overexpression after vascular injury might control VSMC migration and neointima formation. On the other hand, alpha8 integrin gene silencing led to a reduced growth rate, which indicated a dichotomy between VSMC migration and proliferation. / In the later stages of neointima formation, constrictive remodeling plays a major role in late lumen loss. Our data demonstrated that alpha8 integrin is upregulated in the neointima during constrictive remodeling with concomitant luminal narrowing. The importance of this finding was highlighted by results showing that alpha8 integrin was required for the VSMC contractile phenotype evoked by transforming growth factor-beta (TFG-beta) and TFG-beta-induced myofibroblastic differentiation of Rat1 fibroblasts. Thus, it appears that alpha8 integrin expression blockade might reduce contractile remodeling and late lumen loss. Although the mechanism of alpha8 integrin signaling is not yet clear, our findings demonstrate that the alpha8 integrin-induced contractile phenotype is blocked by RhoA inhibitors. Furthermore, alpha8 integrin and RhoA are co-immunoprecipitated, and alpha8 integrin gene silencing reduces RhoA activity. Hence, it is postulated that alpha8-RhoA signaling might be closely intertwined. / Altogether, these studies indicate that alpha8 integrin is a contractile marker of VSMCs and a negative regulator of VSMC migration. Therefore, forced alpha8 integrin expression may be applied to reduce neointima formation. However, alpha8 integrin upregulation during constrictive remodeling concomitant with late lumen loss suggest that it could be involved in lumen narrowing. It seems likely that in therapeutic strategies to reduce restenosis the timeline of interference might be very important. Therefore, alpha8 integrin gene silencing in the later stages of neointima formation might be beneficial.
17

Android balloon game for children

Pulipaka, Mohana Saketh January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Daniel Andresen / Android balloon game application is an android application which helps in improving the children’s vocabulary power. This application provides a graphical user interface with words as questions and balloons as the options. The end user will have to select a balloon in order to select an answer. There are three modules in this application which are game mode, new game and high scores. In the basic module questions like Alpha_bet are included. Also as an enhancement, the game is made interesting by giving the user three lives to clear the levels of the game. Three small balloons are included in the application which resemble the three lives and once an incorrect answer is selected, the green balloon will be replaced by a red balloon depicting an incorrect answer. Also the scores will be computed for every correct option that is selected by the user. The score is incremented by ten points for every correct answer. And for the high score section, the game would maintain the list of top players. High score section will consist of the user’s name, score, time and date for the gameplay. Apart from that a next button is included which helps the user to skip a word which the user finds it difficult to answer. A hint option is also provided in the game which pronounces the word helping the user to guess the word correctly.
18

Patient Satisfaction With Thermal Balloon Endometrial Ablation: A Retrospective Review

Jarrell, April, Olsen, Martin E. 01 August 2003 (has links)
OBJECTIVE: To determine overall patient satisfaction with the balloon endometrial ablation procedure in women with menorrhagia. STUDY DESIGN: Thirty-one women in a university hospital underwent thermal balloon endometrial ablation in the year 2000. Of these, 3 were lost to follow-up. Twenty-eight women were called and asked to participate in a survey that quantified overall satisfaction with the procedure as well as change in menstrual flow and menstrual pain. Women were asked if any further medical or surgical therapy was required to control the bleeding. All patients participated in the study and stated that they underwent the procedure secondary to "heavy bleeding." All operative reports were reviewed and contained menorrhagia, menometorrhagia or dysfunctional uterine bleeding in the preoperative diagnosis. RESULTS: A total of 57% of women reported overall satisfaction with the endometrial ablation procedure, 14% were very dissatisfied, and 4% were neutral. Fifty-seven percent of women reported no bleeding or very decreased bleeding following the procedure, while 11% had slightly decreased bleeding. Thirty-two percent experienced no change, 43% reported decreased menstrual pain, and 57% had no change. Thirteen of 28 women underwent subsequent hysterectomy. CONCLUSION: Less than 60% of women reported saatisfaction with balloon endometrial ablation; and 40% underwent hysterectomy within 1 year of it.
19

Alpha]8[beta]1 integrin and vascular injury : role of [alpha]8[beta1 integrin in restenosis after balloon injury

Zargham, Ramin. January 2007 (has links)
No description available.
20

Ribonucleotide Reductase Inhibitors for Restenosis

Mutchler, Megan Marie 21 August 2008 (has links)
No description available.

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