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Dissertations / Theses on the topic 'Dilation'
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1
Leeds, Kevin Nathaniel. "Dilation equations with matrix dilations." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/31009.
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Michaud, Guy 1971. "Two-dimensional dilation black holes." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22776.
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In this thesis, we study toy models of two-dimensional gravity. We first review two known models: the classical and quantum corrected CGHS models and the quantum corrected model of RST. These two models have black holes solutions with curvature singularities, similar to the Schwartzschild black hole. This singularity becomes naked in the RST model at a certain event during the evaporation. In the third chapter, we build a more general version with new quantum corrections beyond those presented in the RST model, which enable us to find a model without curvature singularities. We will also see that these new quantum corrections can affect the rate of Hawking radiation flowing from the black hole.
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Undrakh, Batzorig. "Rational dilation and constrained algebras." Thesis, University of Newcastle upon Tyne, 2018. http://hdl.handle.net/10443/4052.
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If a set is a spectral set for an operator T, is it necessarily a complete spectral set? That is, if the spectrum of T is contained in , and von Neumann's inequality holds for T and rational functions with poles o of , does it still hold for all such matrix valued rational functions? Equivalently, if is a spectral set for T, does T have a dilation to a normal operator with spectrum in the boundary of ? This is true if is the disk or the annulus, but has been shown to fail in many other cases. There are also multivariable versions of this problem. For example, it is known that rational dilation holds for the bidisk, though it has been recently shown to fail for a distinguished variety in the bidisk called the Neil parabola. The Neil parabola is naturally associated to a constrained subalgebra of the disk algebra, as are many other distinguished varieties. We show that the rational dilation fails on certain distinguished varieties of the polydisk DN associated to the constrained subalgebra AB := C + B(z)A(D). Here A(D) is the algebra of functions that are analytic on the open unit disk D and continuous on the closure of D, and B(z) is a nite Blaschke product of degree N 2. To this end we identify and study the set of test functions B for H1 B := C+B(z)H1(D). Among others, we show that B is minimal (in a sense that there is no proper closed subset of B is su ces).
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Pater, Colleen. "Clinical Characteristics and Rate of Dilation in Turner Syndrome Patients Treated for Aortic Dilatation." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563872367349462.
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Ansari, Zafar A. "Limited Memory Space Dilation and Reduction Algorithms." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/9569.
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In this thesis, we present variants of Shor and Zhurbenko's r-algorithm, motivated by the memoryless and limited memory updates for differentiable quasi-Newton methods. This well known r-algorithm, which employs a space dilation strategy in the direction of the difference between two successive subgradients, is recognized as being one of the most effective procedures for solving nondifferentiable optimization problems. However, the method needs to store the
space dilation matrix and update it at every iteration, resulting in a substantial computational burden for large-sized problems. To circumvent this difficulty, we first develop a memoryless update scheme. In the space transformation sense, the new update scheme can be viewed as a combination of space dilation and reduction operations. We prove convergence of this new algorithm, and demonstrate how it can be used in conjunction with a variable target value method that allows a practical, convergent implementation of the method.
For performance comparisons we examine other memoryless and limited memory variants, and also prove a modification of a related algorithm due to Polyak that employs a projection on a pair of Kelley's cutting planes.
These variants are tested along with Shor's r-algorithm on a set of standard test problems from the literature as well as on randomly generated dual transportation and assignment problems. Our computational experiments reveal that the proposed memoryless space dilation and reduction algorithm (VT-MSDR) and the proposed modification of the Polyak-Kelly cutting plane method (VT-PKC) provide an overall competitive performance relative to the other methods tested with respect to solution quality and computational effort. The r-Algorithm becomes increasingly more expensive with an increase in problem size, while not providing any gain in solution quality. The fixed dilation (with no reduction) strategy (VT-MSD) provides a comparable, though second-choice, alternative to VT-MSDR. Employing a two-step limited memory extension over VT-MSD sometimes helps in improving the solution quality, although it adds to computational effort, and is not as robust a procedure.<br>Master of Science
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Spenler, Stephen John. "Differentially coherent trellis coded modulation with subset dilation." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5963.
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Penninger, Rainer [Verfasser]. "Dilation, Transport, Visibility and Fault-Tolerant Algorithms / Rainer Penninger." Bonn : Universitäts- und Landesbibliothek Bonn, 2014. http://d-nb.info/1060787091/34.
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Kribs, David Wallace. "Non-commuting n-tuples of operators and dilation theory." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ51206.pdf.
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Flórián, Mária 1953. "Endothelial dependent dilation by estrogen through the AKTPKB pathway." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33757.
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Acute administration of estrogen results in the vasodilatation and in the release of nitric oxide (NO) that occurs through activation of the serine-threonine kinase Akt/protein-kinase-B (PKB), which is known to increase the eNOS activity. 10-8 M of 17-beta-estradiol resulted in a left shift of the vasodilatory response to Ach in preconstricted aortic rings from oophorectomized rats (EC50 = 0.7 x 10-8 M with 17-beta-estradiol and 0.15 x 10-7 M of Ach without 17-beta-estradiol, P < 0.05). The effect was blocked by pre-treatment with Wortmannin, a PI(3)K inhibitor. AKT/PKB was phosphorylated in endothelial cells (EC) as early as 1-minute after estradiol-stimulation. Phosphorylation of eNOS and NO release in EC treated with 17-beta-estradiol were also increased. We conclude that the AKT/PKB pathway is involved in the acute release of NO by estrogen.
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Strauch, Christoph [Verfasser]. "On target selection indicated by pupil dilation / Christoph Strauch." Ulm : Universität Ulm, 2021. http://d-nb.info/1235527913/34.
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Carlà, Vito <1978>. "Supercritical fluid polymer processing: anomalous sorption and dilation behaviour." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/613/1/carl%C3%A0.pdf.
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Carlà, Vito <1978>. "Supercritical fluid polymer processing: anomalous sorption and dilation behaviour." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/613/.
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Gregory, Lee. "On the characterisation and dilation of positive quantum stochastic flows." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442302.
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Karvonen, T. (Tuukka). "Ultrasound analysis of the flow-mediated dilation of human arteries." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201404301328.
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The topic of this work was to realize a software-based approach for semiautomatic analysis of flow-mediated dilation (FMD) from ultrasound B-mode image sequences. The work is a continuation of a previous software project, in which B-mode ultrasound image and blood flow / ECG signal extraction, as well as the capability for manual analysis, was made possible. On this base, functionality for the semiautomatic assessment of FMD was built. The result was a software that could be used for the aforementioned analysis. To validate this, functional testing was done. In addition, measurements of FMD were carried out using the software. These measurements were compared against those made by hand, as well as those received from another, commercially available software<br>Tämän työn tavoitteena oli toteuttaa veren virtauksen säätelemän verisuonen laajenemisen (FMD) analysoimiseen tarkoitettu sovellustyökalu. Sovelluksen tuli ottaa syötteenä duplex-ultraääni-mittausdataa, ja antaa puoliautomaattisen analysoinnin jälkeen tuloksena FMD-prosentti. Työ tehtiin lisäkomponenttina aiemmin valmistetulle sovellukselle, joka mahdollisti edellämainitun manuaalisen analyysin. Tuloksena saatiin sovellus, joka pystyi yllämainittuun analyysiin. Sovelluksen toiminnallisuus todennettiin erinäisin funktionaalisin testein, sekä tekemällä sillä mittauksia, joita verrattiin sekä käsintehtyihin, että kaupallisen sovelluksen tuottamiin mittauksiin
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Jackson, Iain Robert. "What can the pupil teach us? : introducing a new measure for the study of infant cognition." Thesis, University of Manchester, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529926.
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The violation of expectation (VOE) paradigm and related habituation methods are the primary tools used to study higher-level cognition in preverbal infants. A common assumption of the paradigm is that longer looking to impossible events than possible events is indicative of infants' surprise at witnessing the impossible. Experiments can thus be designed to reveal infants' prior expectations for the behaviour of objects in the environment and so forth. This thesis explored the nature of infants' expectations in VOE-type events, and introduces pupil dilation as a novel dependent measure in tests of infant cognition. Chapter 1 reviews the history of, and rationale for, the use of habituation testing in infants, and presents the case for pupil dilation's potential as a viable and useful measure for tests in infancy. Chapters 2, 3 and 4 present four experiments in which infants are habituated to either possible or impossible events, before being tested on all event types, in order to explore the role of online learning in the formation of infants' expectations in VOE tasks. Both looking times and pupil dilation data were used as dependent measures in each of these tasks. In Chapter 5 Baillargeon's (1987; Baillargeon, Spelke, & Wasserman, 1985) influential 'drawbridge' experiments and the many subsequent replications of them are reviewed before a further replication is introduced in which the novel contribution of pupil dilation data is assessed. The discussion focuses on the findings of the empirical work of this thesis, and concludes that it is crucial to incorporate efforts to refute hypotheses into the designs of tests for infant cognition, and also that pupil data is a valuable complementary measure to, and potentially even superior than, looking times.
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Norouzi, Siavash. "A Micromechanical Model for Numerical Study of Rock Dilation and Ductility." Thesis, New Mexico Institute of Mining and Technology, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10688951.
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<p> The newly implemented micromechanical model in the CA2 computer program was studied in this work. The purpose was to address some of the issues in the numerical studies involving the Bonded Particle Model (BPM) including unrealistically low <i>q<sub>u</sub></i>/σ<sub> t</sub> ratios, overall dilation behavior, and the post-failure response of rocks. The plasticity model allows both tensile and shear softening of the filling material at the contact points of the particles. It is shown that for a more ductile material, there is less scatter of micro-cracking at the peak load. Furthermore, the ductility parameter appears to be a good tool in controlling the ratio of compressive to uniaxial tensile strength of rock. While the ductility of the filling at the contact points of the particles has a drastic effect on the macroscopic post-peak rock behavior in the direct tensile testing, its role in dictating the post-peak rock behavior in compression is negligible and needs further study. The combined effect of ductility and initial micro-cracking on rock strength characteristics was studied as well. The numerical results suggest that the ratio of Brazilian to direct tensile strength of the simulated material is affected by the initial micro-crack intensity; this ratio is around 1 for a material with no initial micro-cracks but it gradually increases as the initial micro-crack intensity is increased. In terms of the overall dilation behavior, it is shown that the macro-dilation angle can be controlled by means of the micro-dilation angle in a positive correlation provided that the average grain size is sufficiently small or when a joint is involved. As the grain size increases, the resulted macro-asperities suppress the functionality of the micro-dilation angle and consequently, the macro-dilation angle cannot be controlled. Further, it is shown that the genesis pressure can help to govern the overall dilation behavior. This parameter is also able to control the post-peak behavior of a bonded particle system. It is shown that high values of the genesis pressure yield to more brittle BPM system with greater dilation angles and steeper post-peak curves.</p><p>
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Harris, Ryan A. "The flow-mediated dilation response to acute exercise in overweight men." [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3274243.
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Bartolomeo, Lisa Ann. "Pupil Dilation as a Measure of Cognitive Effort During Memory Reconsolidation." Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/579241.
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The pupil is known to dilate in response to numerous cognitive processes, thereby making it a sensitive measure of cognitive effort. While evidence from previous pupilometry studies demonstrates that the pupil dilates during memory encoding and retrieval, the present study aims to determine how pupil dilation reflects the amount of cognitive effort exerted at encoding and retrieval for correctly-recognized and updated information. Ten consenting, volunteer subjects from the University of Arizona completed a classic reconsolidation paradigm that spanned the course of one week, in which subjects were exposed to a total of 68 objects. The paradigm included a directed-forgetting manipulation, in which subjects were instructed to remember or forget certain objects. During encoding and retrieval, pupil diameter was measured using an SMI remote eye tracker. Of these ten subjects, five subjects met procedural protocol and had sufficient data present for analysis. One-way ANOVAs determined there was no significant difference at either encoding or retrieval between correctly-recognized and updated information, regardless of whether subjects were instructed to remember or forget an object at encoding.
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Saathoff, Guido. "Experimental test of relativistic time dilation by laser spectroscopy of fast ions." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965847705.
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Wong, Lisa Elaine. "The effect of altered oxygen tensions and exercise on flow-mediated dilation." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/40096.
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Breathing hypoxia increases vasodilation during exercise, whereas breathing hyperoxia is known to increase vascular resistance. However, little is known about the effect of altered oxygen tensions on endothelial function, particularly following an acute bout of exercise in trained individuals. The purpose of our study was to assess the effects of constant load cycling and different levels of inspired oxygen (FIO₂) on endothelial function measured via flow-mediated dilation (FMD) in healthy trained men. It was hypothesized that exercising while breathing normoxic or hypoxic gas would improve FMD, whereas hyperoxic gas would not alter FMD. The study used a randomized crossover design. Thirteen healthy, recreationally active males (22±3 yrs) volunteered to participate. Subjects completed three graded exercise tests breathing either 16% O₂ (HYPO), 21% O₂ (NOX) or 100% O₂ (HYPER) to determine gas-specific maximal workload (Wmax). Subjects then performed three, 40-minute, constant-load cycling trials at 50% of the gas specific Wmax. Baseline FMD was measured during rest after 30 minutes of gas exposure and 30 minutes following each exercise trial, while breathing the experimental gas. No differences in baseline diameter, shear rate, time-to-peak dilation or FMD were found at rest or after exercise with any gas. Our data indicates that alterations in FIO₂ with and without exercise have no affect on vascular measures in young trained males. Exercise could have been more powerful on influencing the vasculature than changes in FIO₂. Training status and associated vascular remodeling and oxidant production could also account for the lack of change observed with FMD after exercise.
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Chauhan, Sharmila Deepa. "Mechanisms of endothelium-dependant dilation : a study of EDHF and endothelial dysfunction." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397184.
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Wulster, Meghan Carole. "Estradiol-17beta-Oxytocin Induced Cervical Dilation in Sheep: Application to Transcervical Embryo." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36942.
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Experiments were initiated to determine whether exogenous estradiol-17beta (E2) and oxytocin (OT) can be used to dilate the cervix and improve transcervical embryo transfer (ET) procedures for sheep. However, there was concern that the E2-OT treatment may alter luteal function and that embryo quality would decrease as the superovulatory response to FSH increased. In Exp. 1, 32 ewes were assigned to a 2 x 2 factorial array of treatments. On d 7, ewes received an i.v. injection of either 100 micrograms of E2 in 5 mL of 1:1 ethanol:saline or 5 mL of 1:1 ethanol:saline; 12 h later, ewes received i.v. injection of either 400 USP units of OT or saline. Jugular blood was collected on d 7, 8, 9, 10, 12, 14, 16, and 18. Progesterone concentrations were unaffected by the treatments. Experiment 2 was conducted to determine the dose of pFSH needed to induce approximately six corpora lutea (CL). Ten-day Norgestomet implants inserted between d 8-12 of the estrous cycle were used to synchronize estrus in Hampshire and Hampshire x Dorset ewes (n = 23). Ewes received a total of either 0, 18, 27, or 36 mg of pFSH, which was injected i.m. at -24, -12, 0, 12, 24, and 36 h relative to implant removal. The dose at each respective time was 19.4, 19.4, 16.7, 16.7, 13.9, and 13.9% of the total. Ewes received 400 IU of PMSG i.m. at -24 h. The CL were counted laparoscopically on d 6 (d 0 = estrus). Number of CL increased linearly (P &lt; .01) with dose of pFSH; there were 1.8, 3.6, 6.3, and 11.2 CL/ewe, respectively. Experiment 3 was conducted to determine the effect of the E2-OT treatment, mode of transfer or the interaction of E2-OT treatment x mode of transfer on embryo survival and development. Experiment 3 was conducted over two breeding seasons and across two trials. In the first trial ewes were assigned to one of three randomized treatments. Procedural limitations that were later overcome prevented a true 2 x 2 factorial design; therefore, transcervical transfer without hormonal treatment was excluded in the first trial. In the second trial, ewes were assigned to a 2 x 2 factorial array of treatments. On d 6 of pregnancy, embryos rating a fair or better were transferred into recipients either transcervically or laparoscopically. Recipients were administered either an E2 (d 6) - OT (d 7) treatment or an ethanol:saline-saline treatment following the same protocol as in Exp. 1. Embryos were recovered on d 12 in Trial 1 and d 14 in Trial 2. Embryos were evaluated morphologically for development and ranked on a scale of one to four; one represented no development and four represented development to the morphological stages associated with the day of collection. The treatments did not affect the percentage of embryos recovered after transfer or the percentage of embryos that showed some developed. However, there was an effect of mode of transfer on mean rank of embryo development; embryos transferred laporscopically developed further than embryos transferred transcervically (P &lt; .01). This may have been an artifact of a technician effect between trials. There was an effect of E2-OT treatment on transcervical transfer (P &lt; .01), indicating that it may be detrimental to transfer embryos transcervically without dilating the cervix. In conclusion, the E2-OT treatment did not affect luteal function, and the E2-OT treatment can be used to dilate the cervix and enhance success of transcervical transfer of embryos. A 400 IU priming dose of PMSG and a total dose of 27 mg of pFSH can be used to induce the target number of six CL.<br>Master of Science
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Punsalan, David Troy. "A sorption and dilation investigation of amorphous glassy polymers and physical aging." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3035168.
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Lawrenson, John Bernard. "Balloon mitral valvuloplasty at Groote Schuur Hospital : results, complications and short-term follow-up." Master's thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/26331.
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Balloon dilatation of the stenosed mitral valve, in an attempt to relieve symptoms, was developed to replace the surgical procedure of closed mitral valvotomy. This procedure, whereby a balloon tipped catheter is introduced from the femoral vein and directed across the mitral valve after an atrial septal puncture, was developed in 1982. The procedure was first performed at Groote Schuur Hospital in 1988. Two types of dilating balloon (Inoue and Bifoil types) have been used. The aim of this retrospective study was to analyze the results of balloon mitral valvuloplasty procedures performed from 1988 until November 1992. In addition a detailed analysis was made of all complications of the procedure. 118 patients (mean age 30.7 years) underwent 124 attempted procedures. 93 % of attempts were successfully completed and an optimal result was achieved in 76% of patients. Mitral valve area increased from 0.9cm² to 2.0cm². Equivalent results have been achieved with both balloon types. Death occurred in 1.6 % of patients. 2.4 % of patients had severe mitral regurgitation as a complication. 4% of procedures resulted in cardiac chamber perforation. The experience at Groote Schuur has been similar to other centres treating young patients with rheumatic mitral stenosis.
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Chong, Wan-yip. "Aortic root dilation and stiffness in children after repair of Tetralogy of Fallot." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31971660.
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Chong, Wan-yip, and 莊雲葉. "Aortic root dilation and stiffness in children after repair of Tetralogy of Fallot." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31971660.
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Wells, Olivia L. "The Evolution of Fracture Surface Roughness and its Dependence on Slip." Master's thesis, Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/348496.
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Geology<br>M.S.<br>Under effective compression, impingement of opposing rough surfaces of a fracture can force the walls of the fracture apart during slip. Therefore, a fracture’s surface roughness exerts a primary control on the amount of dilation that can be sustained on a fracture since the opposing surfaces need to remain in contact. Previous work has attempted to characterize fracture surface roughness through topographic profiles and power spectral density analysis, but these metrics describing the geometry of a fracture’s surface are often non-unique when used independently. However, when combined these metrics are affective at characterizing fracture surface roughness, as well as the mechanisms affecting changes in roughness with increasing slip, and therefore changes in dilation. These mechanisms include the influence of primary grains and pores on initial fracture roughness, the effect of linkage on locally increasing roughness, and asperity destruction that limits the heights of asperities and forms gouge. This analysis reveals four essential stages of dilation during the lifecycle of a natural fracture, whereas previous slip-dilation models do not adequately address the evolution of fracture surface roughness: (1) initial slip companied by small dilation is mediated by roughness controlled by the primary grain and pore dimensions; (2) rapid dilation during and immediately following fracture growth by linkage of formerly isolated fractures; (3) wear of the fracture surface and gouge formation that minimizes dilation; and (4) between slip events cementation that modifies the mineral constituents in the fracture. By identifying these fundamental mechanisms that influence fracture surface roughness, this new conceptual model relating dilation to slip has specific applications to Enhanced Geothermal Systems (EGS), which attempt to produce long-lived dilation in natural fractures by inducing slip.<br>Temple University--Theses
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Gaebler, David. "Unital dilations of completely positive semigroups." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/2497.
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Semigroups of completely positive maps arise naturally both in noncommutative stochastic processes and in the dynamics of open quantum systems. Since its inception in the 1970's, the study of completely positive semigroups has included among its central topics the dilation of a completely positive semigroup to an endomorphism semigroup. In quantum dynamics, this amounts to embedding a given open system inside some closed system, while in noncommutative probability, it corresponds to the construction of a Markov process from its transition probabilities. In addition to the existence of dilations, one is interested in what properties of the original semigroup (unitality, various kinds of continuity) are preserved.
Several authors have proved the existence of dilations, but in general, the dilation achieved has been non-unital; that is, the unit of the original algebra is embedded as a proper projection in the dilation algebra. A unique approach due to Jean-Luc Sauvageot overcomes this problem, but leaves unclear the continuity of the dilation semigroup. The major purpose of this thesis, therefore, is to further develop Sauvageot's theory in order to prove the existence of continuous unital dilations. This existence is proved in Theorem 6.4.9, the central result of the thesis.
The dilation depends on a modification of free probability theory, and in particular on a combinatorial property akin to free independence. This property is implicit in some Sauvageot's original calculations, but a secondary goal of this thesis is to present it as its own object of study, which we do in chapter 3.
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Forgan, Leonard George. "Gastrointestinal Physiology of Chinook Salmon, Oncorhynchus tshawytscha (Walbaum) with Gastric Dilation Air Sacculitis (GDAS)." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/1285.
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The syndrome known as Gastric Dilation Air Sacculitis (GDAS) has recently been described by Lumsden et al. (2002) for Chinook salmon (Oncorhynchus tshawytscha, Walbaum), in seawater (SW) culture in New Zealand. The syndrome is characterised by distended abdomens, gastric dilation and air sacculitis, increased feed conversion ratios (FCR) and mortality. Consequently, financial returns on affected stocks are greatly reduced. A study into the epidemiology and physiology of the syndrome was initiated, working with the major aquaculture company, The New Zealand King Salmon Company (NZKS). The study revealed causative factors of GDAS. GDAS was experimentally induced only in saltwater by feeding a commercially manufactured low-cohesion pelleted diet. Control groups were fed a different diet with high physical cohesion. Low-cohesion pellets have previously been associated with a high incidence of GDAS in commercial sea cages. These data implicated osmoregulatory stress and physical properties of the feed in GDAS development. In addition, gastrointestinal (GI) physiology in GDAS -affected and -control fish was characterised. The process of GDAS development in O. tshawytscha is characterised by a loss of smooth muscle tone of the stomach as it distends. Laplace's law (P= 2T/r, where P is the distending pressure, T is the tension in the wall and r is the radius of the cylinder) predicts that unless muscle mass increases, the ability of the stomach wall to contract will be lost and consequently a loss of GI motor function will result. Therefore, GI circular smooth muscle integrity in terms of (1) stimulated and maximal contractility, (2) osmoregulatory ability of the intestine and the (3) control of the GI system was studied in pathologically affected (+ve) and unaffected (-ve) smolt. Affected fish showed changes in GI circular smooth muscle function and osmoregulatory dysfunction. Feeding different diets induced distinct gastric evacuation patterns. The intestinal brake hypothesis is presented and argued to be the probable mechanism for GDAS development. GDAS (+ve) serum showed the presence of factors capable of contracting gut smooth muscle. In addition, potential humoral mediators of the intestinal brake in fish were investigated.
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Padilla, Jaume. "Relationship between shear stress and flow-mediated dilation in low and moderate risk populations." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337279.
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Thesis (Ph.D.)--Indiana University, Dept. of Kinesiology, 2008.<br>Title from PDF t.p. (viewed on Jul 29, 2009). Source: Dissertation Abstracts International, Volume: 69-12, Section: B, page: 7339. Adviser: Janet P. Wallace.
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Margaritondo, Giorgio, and Johann Rafelski. "The relativistic foundations of synchrotron radiation." INT UNION CRYSTALLOGRAPHY, 2017. http://hdl.handle.net/10150/625068.
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Special relativity (SR) determines the properties of synchrotron radiation, but the corresponding mechanisms are frequently misunderstood. Time dilation is often invoked among the causes, whereas its role would violate the principles of SR. Here it is shown that the correct explanation of the synchrotron radiation properties is provided by a combination of the Doppler shift, not dependent on time dilation effects, contrary to a common belief, and of the Lorentz transformation into the particle reference frame of the electromagnetic field of the emission-inducing device, also with no contribution from time dilation. Concluding, the reader is reminded that much, if not all, of our argument has been available since the inception of SR, a research discipline of its own standing.
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Hensley, Erika L. "Induced Cervical Dilation in Sheep: Evaluation of the Effects on Fertilization Rates and Embryonic Development." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/44194.
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Experiments were conducted to determine the effects of a treatment used to dilate the
cervix for transcervical AI and embryo transfer on pregnancy or fertilization rates in sheep.
Experiment 1 was conducted as a 2 x 2 factorial, with the main effects of estradiol-17b (E2) and
oxytocin (OT). On d 6 of pregnancy, ewes received (i.v.) 100 mg of estradiol-17b, or saline; 10 h
later, ewes received (i.v.) 400 USP units (20 mL) or saline. Blood samples were collected for
progesterone analysis. Transrectal ultrasonography was used to determine pregnancy on d 25.
Treatment did not affect (c 2 , P > .05) pregnancy rates. For nonpregnant ewes, the
period à E2 à OT interaction (P < .01) was significant.
Experiments were conducted to evaluate the effects of oxytocin and(or) cervical manipulation on fertilization rates. In Exp. 2, nulliparous ewes were
assigned to one of two randomized treatment groups: 1) saline or 2) oxytocin. In Exp. 3, multiparous ewes were assigned to one of two randomized treatment groups: 1) saline-cervical
manipulation or 2) oxytocin-cervical manipulation. Ewes in Exp. 2 and 3 were laparoscopically
inseminated. In Exp. 2 and 3, ewes received (i.v.) either 400 USP units of oxytocin or 20 mL of
saline. In Exp. 2 and 3, oocytes and(or) embryos were collected. Treatment did not affect
recovery, fertilization, or pregnancy rates in Exp.2 and 3. In conclusion, the treatment used to
dilate the cervix in ewes to facilitate the transcervical AI or ET does not seem to affect
fertilization or pregnancy rates.<br>Master of Science
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Shibata, Toshimichi. "Percutaneous Transhepatic Balloon Dilation of Portal Venous Stenosis in Patients with Living Donor Liver Transplantation." Kyoto University, 2010. http://hdl.handle.net/2433/97953.
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Thistlethwaite, John R. "The Role of Acidosis on Vascular Function during Dynamic Handgrip Exercise and Flow-mediated Dilation." Connect to full text in OhioLINK ETD Center, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1216833858.
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Dissertation (Ph.D.)--University of Toledo, 2008.<br>Typescript. "Submitted as partial fulfillment of the requirements for The Doctor of Philosophy degree in Exercise Science." Bibliography: leaves 5-7, 24-34, 61-66, 88-92.
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Ritter, Alyssa. "Prevalence and Natural History of Aortic Root Dilation in a Longitudinal Cohort of Patients with Ehlers-Danlos Syndrome Hypermobility Type." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1458299222.
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Sayre, Brian L. "Oxytocin-induced cervical dilation in sheep: mechanism of action and potential use for nonsurgical artificial insemination." Diss., Virginia Tech, 1995. http://hdl.handle.net/10919/40251.
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Streeter, Daniel. "The Acute Effects of L-Arginine Supplementation on Flow-Mediated Dilation after Resistance Training to Fatigue." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28380.
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The purpose of this study was to determine the effects of acute L-arginine supplementation on the endothelial health in healthy adults by assessing flow-mediated dilation (FMD) and cardiovascular indicators both before and after resistance exercise to fatigue. Thirty (15 male, 15 female) physically active healthy participants (mean ? SD: age 20.4 ? 1.8 years, height 176.9 ? 10.2 cm, body mass 76.0 ? 12.2 kg) volunteered for a randomized, cross-over, double-blind, placebo controlled clinical trial. Participants completed five sets of isokinetic elbow extension/flexion exercise after consumption of either placebo or 3 g L-arginine one hour prior. Baseline brachial artery diameter significantly increased post FMD (p<0.001), post-exercise (p<0.001), post-exercise FMD (p<0.001). There was no significant supplement effect on FMD (p=0.179). The increase in brachial diameter due to fatiguing exercise was not enhanced by acute supplementation with L-arginine nor did supplementation alter FMD responses after exercise.<br>Northland American College of Sports Medicine<br>North Dakota State University. Department of Health, Nutrition, and Exercise Sciences
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Koutsoukos, Georgios. "The regulation of metabolic coronary dilation and reactive hyperemia by nitric oxide in the isolated rat heart." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28802.pdf.
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Horner, Cheyene Kayrene. "A Disorder of Dysregulation: An Examination of Emotional and Pupillary Reactivity in Response to Interpersonal Exclusion in Borderline Personality Disorder." Cleveland State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=csu1624365033281449.
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Neumann, Andersen Grethe. "Systemic sclerosis : vascular, pulmonary and immunological aspects." Doctoral thesis, Umeå universitet, Reumatologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1806.
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In systemic sclerosis (SSc), interstitial lung disease (ILD) and engagement of the vascular system lead to increased morbidity and mortality. The aim of this thesis was to elucidate, in a consecutively included cohort of SSc (limited and diffuse) patients (n = 33), the T cell cytokine profile driving the disease in ILD and to explore the role of matrix metalloproteinase 9 (MMP-9) and its inhibitor: tissue inhibitor of metalloproteinase 1 (TIMP-1) in the extracellular matrix (ECM) degrading process leading to fibrous scarring and honey combing. Moreover, to characterize the role of nitric oxide (NO) in vascular engagement. Peripheral arterial changes cause Raynaud’s phenomenon and digital ulcers. Nitric oxide (NO) a main inducer of vasodilation is produced by endothelial nitric oxide synthase (eNOS) in response to changes in blood flow or by inflammatory cytokine inducible (i) NOS. In the vascular smooth muscle cell (VSMC) NO activates guanylate cyclase to produce cGMP, causing relaxation. We showed elevated plasma nitrate, a degradation product of NO, and increased urinary excretion of nitrate and cGMP. Plasma nitrate correlated with elevated levels of endothelial adhesion molecules: endothelial (E) selectin and vascular adhesion molecule 1, indicating that the activated endothelium is the site of NO synthesis by iNOS. Endothelial staining for E-selectin and the finding of iNOS and eNOS in SSc skin biopsies supported this notion. In SSc increased vascular stiffness may limit the NO vasodilatory effects. We found normal endothelium-dependent (i.e. flow mediated (FMD%)) and endothelium-independent (i.e. nitroglycerin-induced (NTG%)) vasodilation in the brachial artery. Radial arterial wall stiffness measured as maximum increase in pulse pressure (dP/dtmax) was increased. FMD% and especially NTG% correlated negatively and dP/dtmax positively to measures of endothelial inflammation: plasma- nitrate and adhesion molecule levels. Thus inflammatory vascular wall changes may interfere with dilation as may the presence of nitrate tolerance. We found elevated alveolar MMP-9 in both its pro- and active form in ILD. The levels correlated to decline in lung capacity, pointing at a causal relation. We suggest that neutrophils secrete MMP-9, which may degrade collagen IV, (the main constituent of basal membranes), collagen V, gelatins, proteoglycans and elastin. MMP-9 activity is partly regulated by the binding of pro- and active form to TIMP-1. Alveolar TIMP-1, which even stimulates fibroblast ECM synthesis, was increased independent of ILD. The inflammatory process in ILD is orchestrated by activated T helper (h) lymphocytes. We found a mixed Th1/Th2 reaction in SSc alveolar T cells expressing messenger for interferon gamma (Th1), IL-6 and IL-10 (both Th2). No particular cytokine mRNA profile distinguished alveolar T cells in ILD. Neutrophils invaded the bronchial epithelium, which seemed otherwise inert as levels of inflammatory cytokine sensitive transcription factors and their nuclear translocation tended to be low. The neutrophil recruitment pathway is uncertain as chemoattractants and endothelial adhesion molecules were normally expressed. In conclusion, MMP-9 probably causes degradation of lung tissue in ILD and may represent a future therapeutic target. Alveolar T cells show a mixed Th1/Th2 cytokine profile independent of ILD. Neutrophils invade the bronchial epithelium. Activated endothelium produces increased amounts of NO and adhesion molecules and the level of activation influences brachial arterial FMD% and NTG% and radial arterial compliance. Nitrate tolerance may be present.
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Dybäck, Matilda, and Johanna Wallgren. "Pupil dilation as an indicator for auditory signal detection : Towards an objective hearing test based on eye tracking." Thesis, KTH, Skolan för teknik och hälsa (STH), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192703.
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An early detection of hearing loss in children is important for the child's speech and language development. For children between 3-6 months, a reliable method to measure hearing and determine hearing thresholds is missing. A hearing test based on the pupillary response to auditory signal detection as measured by eye tracking is based on an automatic physiological response. This hearing test could be used instead of the objective hearing tests used today. The presence of pupillary response has been shown in response to speech, but it is unstudied in response to sinus tones. The objective of this thesis was to study whether there is a consistent pupillary response to different sinus tone frequencies commonly used in hearing tests and if yes, to determine reliably the time window of this response. Four different tests were done. The adult pupillary response in regard to sinus tone stimuli with four frequency levels (500 Hz, 1000 Hz, 2000 Hz and 4000 Hz), and four loudness levels (silence, 30 dB, 50 dB and 70 dB) was tested (N=20, 15 females, 5 males). Different brightness levels and distractions on the eye tracking screen were investigated in three substudies (N=5, 4 females, 1 male). Differences between silence and loudness levels within frequency levels were tested for statistical significance. A pupillary response in regard to sinus tones occurred consistently between 300 ms and 2000 ms with individual variation, i.e. earlier than for speech sounds. Differences between silence and loudness levels were only statistically significant for 4000 Hz. No statistical difference was shown between different brightness levels or if there were distractions present on the eye tracker screen. The conclusion is that pupillary response to pure sinus tones in adults is a possible measure of hearing threshold for at least 4000 Hz. Larger studies are needed to confirm this, and also to more thoroughly investigate the other frequencies.<br>En tidig upptäckt av hörselnedsättning hos barn är viktig för barnets tal- och språkutveckling. För barn mellan 3-6 månader saknas det en tillförlitlig metod för att mäta hörsel och bestämma hörtrösklar. Ett hörseltest baserad på pupillreaktion på ljud som mäts med en eye tracker bygger på en automatisk fysiologisk reaktion och skulle kunna användas istället för de objektiva test som används idag. Hitintills har pupillreaktion på tal påvisats, men det saknas studier som studerat eventuella reaktioner på sinustoner. Syftet med denna uppsats var att undersöka om det finns en enhetlig pupillreaktion på de olika frekvenserna av sinustoner som vanligen används i hörseltest. Vidare var studiens syfte att fastställa ett tillförlitligt tidsfönster för pupillreaktion. Fyra olika typer av tester utfördes. Pupillreaktionen mot sinustoner med fyra olika frekvensnivåer (500 Hz, 1000 Hz, 2000 Hz och 4000 Hz), och fyra olika ljudnivåer (tystnad, 30 dB, 50 dB och 70 dB) undersöktes i ett test på vuxna deltagare (N=20, 15 kvinnor, 5 män). Olika ljusnivåer och distraktioner på eye tracker-skärmen undersöktes i tre test (N=5, 4 kvinnor, 1 man). Skillnaderna mellan ljudnivåer och frekvensnivåer testades med statistiska tester. Resultaten visade att pupillreaktion på sinustoner inträffade konsekvent mellan 300 ms och 2000 ms med individuella variationer. Denna reaktionstid inträffar tidigare än för taljud. En statistisk signifikant skillnad mellan tystnad och olika ljudnivåer kunde endast ses för frekvensnivån 4000 Hz. Ingen statistisk skillnad uppmättes mellan olika ljudnivåer eller om det fanns distraktioner på eye tracker-skärmen. De i studien framkomna resultaten tyder på att pupillreaktioner mot rena sinustoner hos vuxna är en möjlig metod för att identifiera hörseltrösklar för åtminstone 4000 Hz. Större studier behöver göras för att fastställa detta och en noggrannare undersökning behöver genomföras för de andra frekvenserna.
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Thopy, Amanda J. "Effects of the DASH diet on brachial artery flow mediated dilation in adolescents with pre-hypertension and hypertension." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1307125200.
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Widmann, Andreas, Erich Schröger, and Nicole Wetzel. "Emotion lies in the eye of the listener: emotional arousal to novel sounds is reflected in the sympathetic contribution to the pupil dilation response and the P3." Elsevier, 2018. https://ul.qucosa.de/id/qucosa%3A32716.
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Novel sounds in the auditory oddball paradigm elicit a biphasic dilation of the pupil (PDR) and P3a as well as novelty P3 event-related potentials (ERPs). The biphasic PDR has been hypothesized to reflect the relaxation of the iris sphincter muscle due to parasympathetic inhibition and the constriction of the iris dilator muscle due to sympathetic activation. We measured the PDR and the P3 to neutral and to emotionally arousing negative novels in dark and moderate lighting conditions. By means of principal component analysis (PCA) of the PDR data we extracted two components: the early one was absent in darkness and, thus, presumably reflects parasympathetic inhibition, whereas the late component occurred in darkness and light and presumably reflects sympathetic activation. Importantly, only this sympathetic late component was enhanced for emotionally arousing (as compared to neutral) sounds supporting the hypothesis that emotional arousal specifically activates the sympathetic nervous system. In the ERPs we observed P3a and novelty P3 in response to novel sounds. Both
components were enhanced for emotionally arousing (as compared to neutral) novels. Our results demonstrate that sympathetic and parasympathetic contributions to the PDR can be separated and link emotional arousal to sympathetic nervous system activation.
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Zeigler, Derek E. "On the Influence of Structure and Complexity in Perceived Duration." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1382456987.
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Ne, Jia Yi Anna. "Obesity and Vascular Health." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16000.
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Background: Obesity is an established risk factor for cardiovascular disease. The mechanisms by which obesity confers increased cardiovascular risk have not been fully elucidated but may involve arterial endothelial dysfunction and atherosclerosis among others. Studies examining the association of obesity with markers of atherosclerotic vascular disease have had mixed findings. Accordingly, we undertook two comprehensive systematic reviews of the published literature on obesity and vascular health, specifically one on obesity, brachial flow-mediated dilatation (FMD) and fingertip plethysmography using the EndoPAT device and one on obesity and carotid intima-media thickness (IMT). For vascular measures with sufficient studies (flow-mediated dilatation and carotid intima-media thickness), meta-analysis was undertaken to determine whether these two measures of vascular health differ between obese and healthy weight adults, and the estimated magnitude of the association. Methods: Electronic searches for “Obesity and flow-mediated dilatation”, “Obesity and intima-media thickness” and “Obesity and fingertip plethysmography” were performed using Ovid Medline and Embase databases. Meta-analysis was undertaken for brachial flow-mediated dilatation and carotid intima-media thickness to obtain pooled estimates for the obese and healthy weight adults. Results: Of the 4990 articles (1700 for FMD, 3122 for IMT and 168 for EndoPAT) retrieved, we identified 19 studies that met the study inclusion criteria for flow-mediated dilatation, 19 studies for intima-media thickness and 2 studies for EndoPAT. Meta-analysis demonstrated that obesity was associated with lower flow-mediated dilatation (-1.92 % [95% CI -2.92, -0.92], = 0.0002), and greater carotid intima-media thickness (0.07 mm [95% CI 0.05, 0.08], < 0.00001). Conclusion: Obesity is associated with significant differences in both functional and structural measures of vascular health, suggesting a likely mechanistic pathway through which obesity affects risk of clinical cardiovascular disease.
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Graber, Taylor. "Imaging for Chest Pain Assessment: An Algorithmic Approach Using Noninvasive Modalities to Define Medical vs. Interventional Treatment." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/623439.
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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.<br>To analyze the roles of CCTA, MPI, and CC to formulate a sequential clinical algorithm to use in patients with chest pain, risk factors for CAD, and an abnormal EKG. The goals of the study are to streamline and refine workup, to decrease radiation exposure to patients, and to contain costs. 39 patients underwent CCTA, MPI, and CC within 30 months of each other. CCTA was used to categorize mild, moderate, or severe CAD. MPI used SSS, SDS, TID, and formal reading to define mild, moderate, or severe physiologic ischemia. CC and coronary intervention cine films were analyzed to define and treat anatomical CAD medically or by intervention. Results: There was strong correlation between CCTA, CC, and treatment type (p<0.0001). CCTA was able to stratify all patients with mild or severe ischemia to appropriate treatment groups, and to reduce the need for MPI. With moderate ischemia from CCTA, the additional use of MPI could have reduced the need for 16/18 (89%) patients who underwent CC to undergo further testing. No patients with mild or moderate CAD by CCTA, followed by mild to moderate physiologic ischemia by MPI, needed CC or intervention. 37/39 patients (95%) could have avoided one or more tests using our algorithm. CCTA followed by MPI may be used in symptomatic patients with risk factors for CAD and an abnormal EKG to stratify mild and moderate CAD, and to thereby avoid cardiac catheterization. Our algorithm could lead to savings in healthcare expenditures, save patients from unnecessary invasive procedures, decrease radiation exposure, and total cost.
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Hutchison, Isabel. "The role of sleep in modulating subjective and autonomic arousal." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/the-role-of-sleep-in-modulating-subjective-and-autonomic-arousal(610b32ae-d7e2-426b-bb3b-7a0082de38f2).html.
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Emotion is thought to modulate the long-term fate of memories. Experiences that elicit an emotional response tend to be better remembered than comparatively unemotional events, while the emotional charge associated with these memories diminishes over time. Sleep – in particular rapid-eye movement (REM) and slow-wave sleep (SWS) - has been implicated in both the selective strengthening and affective uncharging of emotional memories. According to the sleep to forget, sleep to remember (SFSR) hypothesis, both processes occur in parallel during REM sleep. Although evidence strongly supports a role of REM sleep in the selective consolidation of emotional memories, it is far less clear to what extent sleep is involved in the development of emotional charge. While some studies support a primary role of REM in habituation (i.e. the decrease of emotional charge), others suggest a more central role of SWS. Further, existing literature indicates that the physiological (bottom-up) and cognitive (top-down) components of emotional responses may be differentially processed across sleep. Chapter 2 proposes complementary functions of REM and SWS in emotional memory processes based on a combination of evidence from rodent and human research. The experiments presented in this thesis employed polysomnography (PSG), subjective arousal testing, pupillometry, targeted memory reactivation (TMR), and transcranial alternating current stimulation (tACs) to investigate the respective roles of REM and SWS in the overnight development of subjective and autonomic arousal in response to negative emotional and neutral stimuli. In Chapter 3 I assessed how subjective and autonomic responses to neutral and negative stimuli develop across 12 hours containing either nocturnal sleep or daytime wakefulness. I found that autonomic reactivity – indexed by pupil dilation – decreased across sleep but not wake, while subjective arousal did not change across either interval. In a further experiment, I investigated whether the placement of sleep within a 24 hour interval would affect habituation. Once again, autonomic arousal decreased significantly. Subjective arousal towards negative stimuli was found to decrease more if sleep followed rather than preceded daytime wakefulness within the 24 hour interval. In Chapter 4 I explored the role of REM sleep in emotional habituation by applying 5 Hz tACs in an attempt to entrain endogenous cortical theta (4-7 Hz) activity, which has previously been associated with emotional memory consolidation in humans. Surprisingly, I found that stimulation was associated with a reduction in theta power and no change in subjective or autonomic habituation compared to the sham control night. In Chapters 5 and 6, I addressed the contribution of memory reactivations during SWS and REM sleep, respectively, in emotional habituation using TMR. In Chapter 5, I found that TMR was associated with a decrease and simultaneous increase in autonomic habituation towards negative and neutral stimuli, respectively, without affecting overnight changes in subjective arousal. In contrast, in Chapter 6, TMR during REM sleep was associated with an increase in subjective habituation towards both neutral and negative stimuli without affecting autonomic responses. In conclusion, my results provide new insights to the role of sleep in emotional habituation. I have provided evidence that targeted memory reactivation during REM sleep can modulate the development of cognitive evaluations of emotion, while TMR during SWS may interfere with autonomic habituation. This suggests distinct emotional processing during REM and SWS, as well as a dissociation between subjective and autonomic habituation across sleep. These results are discussed in the light of previous research and the model of sleep-dependent emotional memory processing proposed in Chapter 2.
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Wolf, Travis. "Coisometric Extensions." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/4926.
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There are two primary sources of motivation for the contents of this thesis. The first is an effort to generalize classical dilation theory, a brief history of which is given in Section 2.1. The second source of motivation is the study of the representation theory of tensor algebras associated to C*-correspondences; these concepts are discussed in Sections 2.2 and 2.4. Although seemingly unrelated, there is a close connection between these two motivating theories.
The link between classical dilation theory and the representation theory of tensor algebras over C*-correspondences was established by Muhly and Solel in their 1998 paper Tensor Algebras over C*-Correspondences: Representations, Dilations, and C*-Envelopes. In that paper, the authors not only introduced the concept of (operator-theoretic) tensor algebras – non-selfadjoint operator algebras that generalize algebraic tensor algebras – but they also developed the representation theory of these algebras. In order to do so, they introduced and made extensive use of a generalized dilation theory for contractions on Hilbert space. In analogy with classical dilation theory, they developed notions of “isometric dilation” and “coisometric extension” for completely contractive representations of the tensor algebra. The process of forming isometric dilations proceeded smoothly, but constructing coisometric extensions proved more problematic. In contrast to the classical case, Muhly and Solel showed that there is a high degree of nonuniqueness involved when building coisometric extensions. This lack of uniqueness proved to be an impediment to developing a full generalization of the dilation and model theories of Sz.-Nagy and Foias. In this thesis, we introduce a way to manage the ambiguities that arise when forming coisometric extensions. More specifically, we show that the notion of a transfer operator from classical dynamics can be adapted to this setting, and we prove that when a transfer operator is fixed in advance, every completely contractive representation of the tensor algebra admits a unique coisometric extension that respects the transfer operator in a fashion that we describe in Chapter 5. We also prove a commutant lifting theorem in the context of coisometric extensions.
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Serafi, Abdulhalim Salim. "The effect of acute elevation of wall stress in patients with various degrees of left ventricular dilation and/or hypertrophy." Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413581.
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Timsina, Roshan. "Influence of Time of Day and Intermittent Aerobic Exercise on Flow-Mediated Dilation and Plasma ET-1 in Healthy Adults." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1594991151327762.
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