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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.
531

Intramuscular Anabolic Signaling and Endocrine Response Following Different Resistance Exercise Protocols In Trained Men

Gonzalez, Adam 01 January 2015 (has links)
The mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway appears to be the primary regulator of protein synthesis and growth. While resistance exercise paradigms are often divided into hypertrophy (HYP) and strength (STR) protocols, it is unknown whether these protocols differentially stimulate mTORC1 signaling. The purpose of this study was to examine mTORC1 signaling in conjunction with circulating hormone concentrations following a typical lower-body HYP and STR resistance exercise protocol. Ten resistance-trained men (24.7±3.4y; 90.1±11.3kg; 176.0±4.9cm) performed each resistance exercise protocol in a random, counterbalanced order. Blood samples were obtained at baseline (BL), immediately (IP), 30 minutes (30P), 1 hour (1H), 2 hours (2H), and 5 hours (5H) post-exercise. Fine needle muscle biopsies were completed at BL, 1H, and 5H. Electromyography of the vastus lateralis was also recorded during each protocol. HYP and STR produced a similar magnitude of muscle activation across sets. Myoglobin and lactate dehydrogenase concentrations were significantly greater following STR compared to HYP (p=0.01-0.02), whereas the lactate response was significantly higher following HYP compared to STR (p=0.003). The GH, cortisol, and insulin responses were significantly greater following HYP compared to STR (p=0.0001-0.04). No significant differences between protocols were observed for the IGF-1 or testosterone response. Intramuscular anabolic signaling analysis revealed a significantly greater (p=0.03) phosphorylation of IGF-1 receptor at 1H following HYP compared to STR. Phosphorylation status of all other signaling proteins including mTOR (mammalian target of rapamycin), p70S6k (ribosomal S6 kinase 1), and RPS6 (ribosomal protein S6) were not significantly different between trials. Despite significant differences in markers of muscle damage and the endocrine response following STR and HYP, both protocols appeared to elicit similar mTORC1 activation in resistance-trained men.
532

Comparative Retrospective Analysis Assessment Of Extracellular Volume Excess In Hypertensive Hemodialysis Patients

Serwaah-Bonsu, Amma 01 January 2011 (has links)
Cardiovascular disease, including hypertension, accounts for almost 50% of the deaths in patients with end stage renal disease (ESRD) on hemodialysis (HD) yet hypertension remains very poorly controlled in this population. The purpose of this study was to retrospectively compare control of hypertension in hemodialysis (HD) patients when extracellular volume (ECV) was assessed and managed by clinical parameters and physical assessment data alone with control of hypertension when data from blood volume monitoring (BVM) technology was also used to assess and manage ECV in a freestanding outpatient hemodialysis unit. The main cause of hypertension in the ESRD population has been identified as increased ECV most likely secondary to increased interdialytic weight gain and failure to attain and maintain patient’s dry weight. HD nurses often employ clinical parameters along with physical examination to determine a patient’s pre, intra, and post dialytic fluid status and this approach can have a high index of error. BVM technology is being used in many hemodialysis units to assist with assessment of ECV. A comparative retrospective chart review was used to collect data for this project. A descriptive, cross-sectional design was employed to answer the question:“Are hypertensive hemodialysis patients who dialyze in a freestanding dialysis unit, where BVM technology is utilized, more likely to be normotensive as defined by a pre dialysis blood pressure of less than 140/90 and post dialysis blood pressure less than 130/80”? A pilot study was conducted to determine if the patient population and data were available in existing patient records for extrapolation. Approval for the study was obtained from the University IRB. A convenience sample was obtained from the records of patients meeting the inclusion criteria. Variables were measured and analyzed using iv descriptive statistics such as sampled paired T-test to compare pre and post BVM systolic, diastolic blood pressures, intradialytic weight gain, serum Albumin and sodium levels, and hemoglobin. A p-value of 0.05 was assigned for statistical significance. Data analysis showed there were statisticaly significant differences in the pre dialysis systolic blood pressure, post BVM, and the serum sodium pre and post BVM when the two groups were compared These statistically significant findings support a correlation between reduction in the HD patient’s ECV and improved blood pressure control. The reduction of pre-dialysis SBP was significant because many patients on hemodialysis have systolic hypertension that may or may not coexist with diastolic hypertension. The findings of this study may be used to formulate a protocol to be used in the HD units where the BVM is available. The protocol would rely on accurate nursing assessment of clinical parameters, patient verbalizations of symptoms, and the routine use of the BVM in order to continuously assess the patient’s fluid status. Future research recommendations include conducting the study in a population closer to the national sample, a study where glucose readings and /or hemoglobin A1C levels are measured to assess the impact of glucose on ECV, and which antihypertensive class of medication works best with BVM technology to effectively manage hypertension in this population.
533

One-Dimensional, Finite-Rate Model for Gas-Turbine Combustors

Rodriguez, Carlos G. 05 August 1997 (has links)
An unsteady, finite-rate, one-dimensional model has been developed for the analysis for gas-turbine combustors. The basis of the model is the one-dimensional, integral form of the conservation equations for multi-species, non-equilibrium, reacting mixtures. Special procedures were devised for the flow-division of the inlet flow into primary- and annular-flows, for both straight- and reverse-flow combustors. This allows the model to handle complete combustor configurations, which at present are beyond the reach of more sophisticated CFD tools. The model was validated with a steady-state analytical solution for a basic problem, and with steady-state results from a production code applied to a production combustor. Additional calculations show the ability of the code to predict blow-out due to rich and lean mixtures, and to predict the response of a combustor to perturbations in operating and boundary conditions. / Ph. D.
534

CFD Simulation of Droplet Formation Under Various Parameters in Prilling Process

Muhammad, A., Pendyala, R., Rahmanian, Nejat 09 1900 (has links)
No / A computational fluid dynamics (CFD) model is used to investigate the droplet formation and deformation under the influence of different parameters. Droplet breakup phenomenon depends on several factors such as viscosity, velocity, pressure difference, and geometry. The most important parameter for droplet breakup is the Weber number (We) which is the ratio of disrupting aerodynamics forces to the surface tension forces. Volume of fluid (VOF) model is used in present work to simulate the droplet breakup. This work presents the effect of liquid velocity, viscosity, and orifice diameters on droplet formation and breakup.
535

Development of a Thick Gas Electron Multiplier Detector for Microdosimetry

Orchard, Gloria M. 12 1900 (has links)
<p> In experimental microdosimetry one of the goals is to measure the absorbed dose in microscopic volumes of tissue. The traditional spherical tissue-equivalent proportional counter (TEPC) is the most common detector currently used for microdosimetry. A new microdosimetric detector based on a thick gas electron multiplier (THGEM) was developed. To investigate the feasibility of the THGEM type detector for microdosimetry, a prototype detector was designed and manufactured. The THGEM detector is robust, easy to manufacture and is cost effective. The THGEM foil is composed of a thin FR4-epoxy insulator coated with copper on both sides. The THGEM contains 32 holes each with a diameter of 0.35 mm and pitch of 0.64 mm. The sensitive volume of the detector is a right cylinder with a diameter of ~5 mm and height of ~5 mm and is located in the center of the detector. Systematic tests were conducted at the McMaster Accelerator Laboratory to investigate its overall performance. A neutron-gamma ray radiation field was generated using the 7Li(p,n) reaction. The detector was operated at low bias voltages initially to test the stability and then the relative multiplication gain was measured as a function of the operating high voltage. The detector performance was observed with different THGEM insulator thicknesses ranging from 0.12 mm to 1.48 mm. The multiplication gain was assessed and both neutron and gamma-ray radiation was detected by the THGEM detector. The spectra obtained with the THGEM detector were analyzed and compared to the data collected with the standard spherical TEPC. The investigations provided information about the THGEM detector operation for microdosimetry and the THGEM microdosimetric spectra observed are comparable to the standard TEPC data.</p> / Thesis / Doctor of Philosophy (PhD)
536

Three-Dimensional Relationships Among Traffic Flow Theory Variables: A Comparative Study

Richardson, William Robert Charles 04 1900 (has links)
<p> This paper is a further investigation of Gilchrist and Hall's work on the three-dimensional relationships in traffic flow theory variables (Gilchrist and Hall, 1989). The investigation examines the three variables of traffic flow (speed, volume, and occupancy). Gilchrist and Hall's data is then compared with data used in this analysis. The traffic variables are first examined by the traditional two-dimensional model and then they are examined obliquely in three-dimensional space. The resulting oblique views of the data are reviewed for points of agreement with conclusions made by Gilchrist and Hall. Resultant views of the data suggest that there is a plane along which all of the uncongested data fall. However, this phenomena only occurs when there is a wide range of speed values in the data set. The results also suggest that low-speed congested data do not lie on the same plane as do the uncongested data. It is concluded that low-speed congested data do not lie on a plane at all.</p> / Thesis / Candidate in Philosophy
537

Real-time Rendering of Burning Objects in Video Games

Amarasinghe, Dhanyu Eshaka 08 1900 (has links)
In recent years there has been growing interest in limitless realism in computer graphics applications. Among those, my foremost concentration falls into the complex physical simulations and modeling with diverse applications for the gaming industry. Different simulations have been virtually successful by replicating the details of physical process. As a result, some were strong enough to lure the user into believable virtual worlds that could destroy any sense of attendance. In this research, I focus on fire simulations and its deformation process towards various virtual objects. In most game engines model loading takes place at the beginning of the game or when the game is transitioning between levels. Game models are stored in large data structures. Since changing or adjusting a large data structure while the game is proceeding may adversely affect the performance of the game. Therefore, developers may choose to avoid procedural simulations to save resources and avoid interruptions on performance. I introduce a process to implement a real-time model deformation while maintaining performance. It is a challenging task to achieve high quality simulation while utilizing minimum resources to represent multiple events in timely manner. Especially in video games, this overwhelming criterion would be robust enough to sustain the engaging player's willing suspension of disbelief. I have implemented and tested my method on a relatively modest GPU using CUDA. My experiments conclude this method gives a believable visual effect while using small fraction of CPU and GPU resources.
538

From area to volume, experimental youth housing in Gottsunda

Hedström, Natalia January 2023 (has links)
The base for this project is the challenge of housing shortage. This is occurring all over Sweden and Uppsala is no exception. The Municipality of Uppsala is growing fast, and the district of Gottsunda is one of the neighborhoods with a major future plan of densification and development. These plans for Gottsunda are stated in the “Gottsunda Planning Program” made by the municipality, where they establish the districts’ current issues, answers and future initiatives.  Category housing is lacking in this part of Uppsala, such as youth and student housing. Only 40% of Uppsala's students have access to student housing according to the municipality's document "Housing for All" and this laid the foundation for my project. The goal was to create compact housing with qualities found in other small spaces like tiny houses and compact living, both being a big inspiration.  This has resulted in my project ”From area to volume” where the means of creating a small dwelling unit that has everything except for a bed already included is explored. It is an exploration in volume and maximizing qualities and well planned spaces at the same time as minimizing the area the dwelling needs. Wanting the tenants to have the opportunity of a community and access to physical and social activities as the document "Guidelines for student and researcher housing" written by Akademiska hus describes as important qualities for sustainable quality of life.  This being accomodated by large communal spaces such as study spaces, social rooms, mobility hall, balconies, gym, yard and more.
539

Low left atrial volume is an independent predictor of persistent hypotension after carotid artery stenting / 低左房容積は頸動脈ステント留置術後遷延性低血圧の独立した予測因子である

Maekawa, Kota 23 January 2024 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13584号 / 論医博第2304号 / 新制||医||1070(附属図書館) / (主査)教授 江木 盛時, 教授 湊谷 謙司, 教授 江藤 浩之 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
540

Parzsweep: A Novel Parallel Algorithm for Volume Rendering of Regular Datasets

Ramswamy, Lakshmy 10 May 2003 (has links)
The sweep paradigm for volume rendering has previously been successfully applied with irregular grids. This thesis describes a parallel volume rendering algorithm called PARZSweep for regular grids that utilizes the sweep paradigm. The sweep paradigm is a concept where a plane sweeps the data volume parallel to the viewing direction. As the sweeping proceeds in the increasing order of z, the faces incident on the vertices are projected onto the viewing volume to constitute to the image. The sweeping ensures that all faces are projected in the correct order and the image thus obtained is very accurate in its details. PARZSweep is an extension of a serial algorithm for regular grids called RZSweep. The hypothesis of this research is that a parallel version of RZSweep can be designed and implemented which will utilize multiple processors to reduce rendering times. PARZSweep follows an approach called image-based task scheduling or tiling. This approach divides the image space into tiles and allocates each tile to a processor for individual rendering. The sub images are composite to form a complete final image. PARZSweep uses a shared memory architecture in order to take advantage of inherent cache coherency for faster communication between processor. Experiments were conducted comparing RZSweep and PARZSweep with respect to prerendering times, rendering times and image quality. RZSweep and PARZSweep have approximately the same prerendering costs, produce exactly the same images and PARZSweep substantially reduced rendering times. PARZSweep was evaluated for scalability with respect to the number of tiles and number of processors. Scalability results were disappointing due to uneven data distribution.

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