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1
Wood, Deborah Jane. "Pressure-impulse impact problems and plunging wave jet impact." Thesis, University of Bristol, 1997. http://hdl.handle.net/1983/c3dbd4c5-5082-4c71-a16e-3daa969e22ee.
Повний текст джерела
2
Cox, Simon John. "Pressure impulses caused by wave impact." Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266731.
Повний текст джерела
3
Bossy, Steve. "Academic pressure and impact on Japanese students." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29528.pdf.
Повний текст джерела
4
Bossy, Steve. "Academic pressure and impact on Japanese students." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35314.
Повний текст джерелаАнотація:
This study explores the tremendous pressure Japanese students must endure in the pursuit of academic achievement. It identifies the sources of student's pressure and discusses the cultural, social, and economic conditions that influence a fiercely competitive educational system. The focus of this study is the impact of academic pressures on Japanese students.Japanese education is a single-minded drive for achievement that results in what many refer to as examination hell. The university entrance examination is at the root of the pressures that are placed on students and is the primary mechanism responsible for driving competition. The life-long ramifications of students performance on this examination are far reaching. As a result, the pressures that are exerted upon students to achieve are overwhelming. Mothers, teachers, peers, and society contribute to the pressures that are placed on students to achieve, while many children continue to fall victim to emotional, psychological, and physical harm.
The study provides richly descriptive narrative accounts of student's experiences, thoughts and feelings seen from a student's perspective. The study gives voice to Japanese students and invites them to tell it like it is.
5
Owais, Tariq Muhammad. "Impact of pressure on Sintering of Cemented Carbides." Thesis, KTH, Materialvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-123170.
Повний текст джерелаАнотація:
In this Master Thesis work, the effect of pressure on sintering of cemented carbides is investigated. Special focus hasbeen given to the residual porosity after sintering. It is well known that sintering shrinkage depends on binder phasecontent, grain size, temperature and pressure. Thus 4 different cemented carbides grades were selected. The gradeswere pressed into standard products and TRS (Tensile Rupture Strength) rods with two different shrinkage factors.These were then sintered at different pressures and temperatures. Thereafter the impact of pressure on propertiessuch as Density, Coercivity, Porosity and TRS were analyzed. The observations were further supported with Weibullprobability analysis and fracture surface analysis in SEM.It has been shown that there exists a distinct threshold pressure at which significant reduction in porosity occurs forgiven compacted densities. For 3 out of 4 cemented carbide grades it has been observed that P2 sintering pressure issufficient to meet desired product characteristics. The fourth grade required a minimum sintering pressure of P4 toachieve desired quality criteria. Moreover it has been concluded that an increased sintering pressure increasesmaterial strength, as compared to vacuum sintering, thereby reducing the amount of early failures caused by poresduring TRS test. Keywords: Cemented Carbides, Pressurized Sintering, Tungsten carbide, Porosity, Vacuum sintering, TensileRupture Strength, Weibull analysis, Fracture surface analysis.
6
Berglind, Robin. "Impact of Sidewall Pressure on High Voltage Cables." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-16795.
Повний текст джерелаАнотація:
When a high voltage cable is transported throughout factory it is affected by sidewall pressure in cable bends between the roller supports and the cable. The problem is when the sidewall pressure is too high it will deform the cable which can have a negative impact on the conductivity of the cable. The roller supports can also get damaged because of fatigue. These negative consequences are the subject to exploration by implementing known analytical solution of contact mechanics developed by Hertz together with finite element analysis and experimental testing. Two possible methods of measuring the radial force is studied to be able adjust the roller supports positions to reduce the sidewall pressure on the cable. The first one is to use the pressure film to determine the radial force. The second one is to by measuring the compression in cable to thereafter translate it to radial force by having the relation between compression and radial force for the specific cable. Two different types of high voltage cables, a direct current (DC) cable and an alternating current (AC) cable is studied by using finite element method and experimental tests to see the relation between the compression and radial force in the cable. Also in these experimental tests the pressure films are used and evaluated to see if this measuring technique combined with Hertzian’s theory make it possible determining the radial force. For the method of using the pressure films to determine the radial force the result shows it is difficult to translate the pressure from the films to radial force for a high voltage because of the cable’s armouring wires. The conclusion about these the pressure films is that they are good to use to describe the compression and can be used as relative measurement between the rollers but not for determine the radial force. The result shows it is a possible to describe relation between compression and radial force for a high voltage cable and use this information to determine the radial force by measuring the compression. But the conclusion is that it is ineffective and less accurate way of measuring the radial force. These results from this thesis are important for further research within the area and they help creating a greater understanding of sidewall pressure related problems in cables.
7
Ling, Yang. "The Impact of Emotional Intelligence on Auditor Judgment." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/509.
Повний текст джерелаАнотація:
Emotions are an important underlying factor that may interact with pressure and other situational variables to influence auditors’ judgments and decisions. This study seeks to identify emotional intelligence (EI) as a key factor in dealing with emotions and pressures in an audit context. In this paper, I focus on how EI may influence the relation between job pressures (i.e., time budget pressure and client incentive pressure) on the auditor’s judgment. Specifically, I investigate the moderating effect of emotional intelligence on auditor judgments when auditors experience both internal and external pressures. The results suggest that the moderating influence of EI on auditor judgments can effectively reduce auditors’ tendency to engage in dysfunctional behavior in order to improve audit quality. Furthermore, there is a positive relation between EI and professional skepticism suggesting that auditors with high EI are more skeptical and assess higher risk than auditors with low EI. Finally, moderation analysis suggests that EI is a significant mechanism which drives the joint effects of different type of pressures on auditor judgments.
8
Zhao, Yingzi, and 趙瑩子. "Acute and chronic impact of pressure on vascular responsiveness." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/207185.
Повний текст джерелаАнотація:
Hypertension leads to vascular complications including endothelial dysfunction, heart failure and stroke. The purpose of the present studies was to investigate the chronic and acute impact of high pressure on vascular responsiveness.
In Study I, isometric tension measurements demonstrated that contractions to phenylephrine, in the presence of indomethacin (inhibitor of cyclooxygenase), were smaller in aortae of spontaneously hypertensive rats (SHR) with, than in those without, endothelium, while they were comparable in such preparations of normotensive Wistar-Kyoto rat (WKY); the difference in SHR aortae was not affected by L-NAME [inhibitor of nitric oxide synthase (NOS)]. This endothelium-dependent, NOS-independent inhibition of phenylephrine-induced contraction was greater in older SHR (36 versus 18 weeks), and abolished by NO scavengers and ODQ (inhibitor of soluble guanylyl cyclase). It was observed not only in the presence of indomethacin but also apocynin (antioxidant), but inhibited by diphenyleneiodonium (inhibitor of cytochrome P450 reductase). These results suggest that the endothelium-dependent, eNOS-independent inhibition is caused by NO produced by cytochrome P450 reductase in the endothelium of the SHR aorta.
Study II investigated the mechanisms underlying the reduced contractions to prostaglandin E2 [agonist of prostaglandin E2 and thromboxane-prostanoid (TP) receptors] by a previous exposure to phenylephrine (agonist of α1-adrenoceptor) in the aortic smooth muscle of the SHR. This inhibition induced by the pre-activation of α1-adrenoceptor was augmented in aortae of older SHR (36 versus 18 weeks) and was not present in WKY preparations. Pre-exposure to the protein kinase C (PKC) activator, phorbol 12,13-dibutyrate, also inhibited subsequent contractions to prostaglandin E2 in SHR aortae. Inhibition of PKC by calphostin C abolished the effect of pre-exposure to phenylephrine. The mRNA expressions of PKC isoforms differed in WKY and SHR smooth muscle. These experiments suggest that in the SHR but not the WKY aorta, α1-adrenergic activation causes heterologous desensitization of TP receptor through activation of a specific PKC isoform(s).
In Study III, experiments were performed in a pressure myograph to determine whether or not acute elevation of transmural pressure in the isolated carotid artery of adult mouse (10-12 weeks) impairs endothelium-dependent dilatation by increasing angiotensin II expression or by directly activating AT1 receptors. Transient exposure of arteries to increased pressure (150 mmHg, three hours) inhibited endothelium-dependent, NO-mediated dilatations to acetylcholine, but did not affect responses to the NO donor DETA-NONOate. Inhibiting angiotensin II signaling or angiotensin converting enzyme prevented the impairment of endothelium-dependent dilatation by elevated pressure. Elevated pressure increased the expression of angiotensinogen [precursor of angiotensin II]. Thus, exposure of carotid arteries to elevated pressure leads to local release of angiotensin II, which activates AT1 receptors to cause endothelial dysfunction.
In summary, chronic increased pressure increased the endothelial NO release produced by cytochrome P450 reductase from nitrate and developed the heterologous desensitization of TP receptor caused by PKC in SHR aorta. Acute increased pressure impaired endothelium-dependent NO-mediated vasodilatation by activation of local angiotensin system in adult mouse carotid artery. These processes likely contribute to the pathogenesis of hypertension-induced vascular dysfunction and organ injury.published_or_final_version
Pharmacology and Pharmacy
Doctoral
Doctor of Philosophy
9
Hawkesworth, Sophie Ann. "Impact of maternal nutritional supplementation on offspring blood pressure." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2010. http://researchonline.lshtm.ac.uk/682418/.
Повний текст джерелаАнотація:
Observational studies on the association between birth weight and adult blood pressure provide suggestive evidence that exposures during fetal development can have lasting impacts on health. The effect of maternal nutrition during pregnancy on offspring blood pressure has been demonstrated in animal models, but data from cohort studies in humans have proven inconclusive. The follow-up of randomised controlled trials of nutritional supplementation during pregnancy can add high quality data to this research field; this thesis focuses on the effects in three separate trials. Protein energy supplementation provided to pregnant women in rural Gambia was unrelated to offspring blood pressure at 11-17 years old (n=1267). Again in The Gambia, maternal calcium supplementation compared to placebo was also unrelated to offspring blood pressure at 5-10 years old (n=350). In rural Bangladesh there was no effect of maternal food or multiple micronutrient supplementation on offspring systolic blood pressure at 4.5 years old (n=2335). The micronutrient intervention was also unrelated to offspring diastolic blood pressure, but there was evidence that an early invitation to enter a governmental food supplementation programme was associated with marginally lower diastolic blood pressure: 0.58mmHg (95% Cl: 0.06,1.11; P: 0.03). In this setting, randomisation to receive counselling to promote exclusive breast feeding was not associated with offspring blood pressure at 4.5 years of age and none of the interventions were associated with offspring kidney function, assessed as ultrasound-obtained volume and glomerular filtration rate calculated from plasma Cystatin C. These data suggest that the maternal diet during pregnancy, at least those aspects of intake that can be altered during supplementation trials, may not be directly relevant for the determination of offspring blood pressure. Nutritional exposures during other stages of the life course may prove to be more important
10
Singh, Charleen. "The Impact of Nursing Interventions on Pediatric Pressure Injuries." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3542.
Повний текст джерелаАнотація:
Hospitalized children are vulnerable to pressure injuries. Multiple methods are available to decrease pressure injuries. One specific method is the pediatric pressure injury prevention bundle, which includes device rotation, moisture management, positioning, skin assessment, and support surface management. Although this prevention bundle is available nationwide, it is not known if this type of bundled methodology helps decrease pressure injuries in hospitalized children. Secondary data regarding nursing interventions implemented as a bundle and pressure injury rates from a large pediatric hospital consortium were used to address this gap in the literature. The research questions explored the impact of the pressure injury prevention bundle on pressure injury rates over time and further dissected the data to determine the significance of each intervention in the treatment bundle. Benoit and Mion's model for performance improvement along with the continuous quality improvement model used by the hospital consortium guided the study. The secondary data sample included 102 children's hospitals participating in the national initiative Solutions for Patient Safety. Pearson correlation statistics revealed a significant inverse relationship between nursing interventions and pressure injury rates for hospitalized children. The findings indicated a 57% reduction in rates of pressure injuries over 5 years with nursing participation in implementing the pediatric pressure injury prevention bundle. The impact of any one intervention over the bundle was inconclusive. Positive social change is seen in the ability to decrease pressure injuries in hospitalized children by nurses' implementation of a pediatric pressure injury prevention bundles.
11
Watts, Travis James. "DIRECT MEASUREMENT OF CROSSTIE-BALLAST INTERFACE PRESSURES USING GRANULAR MATERIAL PRESSURE CELLS." UKnowledge, 2018. https://uknowledge.uky.edu/ce_etds/74.
Повний текст джерелаАнотація:
The magnitudes and relative pressure distributions transmitted to the crosstie-ballast interface of railroad track significantly influences the subsequent behavior and performance of the overall track structure. If the track structure is not properly designed to distribute the heavy-axle loads of freight cars and locomotives, deficiencies and inherent failures of the crossties, ballast, or underlying support layers can occur, requiring substantial and frequent maintenance activities to achieve requisite track geometrical standards. Incorporating an understanding of the pressure distribution at the crosstie-ballast interface, appropriate designs can be applied to adequately provide a high performing and long-lasting railroad track. Although this can be considered a simple concept, the magnitudes and distributions of pressures at the crosstie-ballast interface have historically proven to be difficult to quantifiably measure and assess over the years.
This document describes the development and application of a method to measure average railroad track crosstie-ballast interfacial pressures using timber crossties and pressure cells specifically designed for granular materials. A procedure was specifically developed for recessing the cells in the bottoms of timber crossties. The validity of the test method was initially verified with a series of laboratory tests. These tests used controlled loads applied to sections of trackbed constructed in specifically designed resilient frames. The prototype trackbed section was intended to simulate typical in-track loading conditions and ballast response.
Cells were subsequently installed at a test site on an NS Railway well-maintained mainline just east of Knoxville, TN. Six successive crossties were fitted with pressure cells at the ballast interface below the rail seat. Pressure cells were also installed at the center of two crossties where the ballast is typically not tamped or consolidated. Trackbed pressures at the crosstie-ballast interface were periodically measured for numerous revenue freight trains during a period of twenty-one months. After raising and surfacing the track, the ballast was permitted to further consolidate under normal train traffic before again measuring pressures. Having the ballast tightly and uniformly compacted under crossties is important to ensuring representative and reproducible pressure measurements.
Measured maximum pressures under the rail at the crosstie-ballast interface ranged from 20 to 30 psi (140 to 210 kPa) for locomotives and loaded freight cars with smooth wheels producing negligible wheel/rail impacts. Crosstie-ballast interface pressures were typically 3 psi (20 kPa) maximum for empty freight cars with smooth wheels. Heavily loaded articulated intermodal car pressures for shared trucks tended to reach nearly 40 psi (280 kPa), actually higher than locomotive-produced pressures. The recorded pressures under the center of the ties were normally negligible, less than 1 psi (7 kPa) for locomotives and loaded freight cars.
Wheel-Rail force parameters measured by nearby wheel-impact load detectors (WILD) were compared to crosstie-ballast pressure data for the same trains traversing the test site. Increases in peak WILD forces, either due to heavier wheel loads or increased impacts, were determined to relate favorably to increases in recorded trackbed pressures with a power relationship. The ratios between the peak and nominal wheel forces and trackbed pressures also have strong relationships.
12
Olsen, Gregory Dana. "Experimental investigation into catastrophic failure of pressure vessels due to hypervelocity impact /." Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008411.
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13
Danell, Lindström Emma, and Graziella El-Ghorayeb. "Evaluation of Impact Loading Rates Dependency on Prescale Pressure Film." Thesis, KTH, Skolan för teknik och hälsa (STH), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215344.
Повний текст джерелаАнотація:
Migraine is the third most common medical condition in the world. Xiaogai Li have a hypothesis that implies that a hit to the head when first sensing the aura symptoms will stop the migraine attack. An investigation was made to ensure that the blow does not cause a head injury. The prescale pressure film from Fujifilm is a sensor that measures pressure and the pressure distribution. It is supplied with charts to determine the pressure when purchased. The pressure film was used to measure the reached loading impact from the blow. The new chart for the pressure film would in that case be used to create simulations to study the potential brain damage a hit to the head can result in. This paper examines whether loading rates has an influence on a prescale pressure film from Fujifilm, in order to create new pressure charts if such dependency is found. The testing was made with the help of a loading machine where the desired force could be set. The results showed a lower color density in the test results when comparing with the provided charts. The reason for this is unknown, although it could be a consequence of the environmental conditions that the pressure film was held in. The conclusion made by studying the results was that no loading rate dependency exists.
14
Rangel, Gonzalez Ricardo Elias. "The impact of shale pressure diffusion on 4D seismic interpretation." Thesis, Heriot-Watt University, 2016. http://hdl.handle.net/10399/3176.
Повний текст джерелаАнотація:
Shale typically has a low but non-negligible permeability of the order of nanodarcys (recognized an appreciated in production of unconventional resources), which could affect the magnitude and pattern of the pressure in conventional reservoirs over the lifetime of a producing field. The implications of this phenomenon for reservoir monitoring by 4D seismic can be significant, but depend on the geology of the field, the time-lines for production and recovery, and the timing of the seismic surveys. In this PhD thesis I developed an integrated workflow to assess the process of shale pressure diffusion and its elastic implications in the 4D seismic interpretation of four conventional reservoirs (three North Sea case studies and one from West Africa), with different geological settings (shallow marine and turbidites) and production mechanisms. To accomplish that, first, a detailed petrophysical evaluation was performed to characterize the overburden, intra-reservoir and underburden shales. Next, the simulation models were adjusted to activate the shale-related contributions, and then, applying simulator to seismic workflows, 3D and 4D synthetic seismic modelling were performed, for comparison with the observed seismic data and to establish the impact of the shale pressure diffusion in the elastic dynamic behaviour of the reservoir. This work also includes a case study where evaluation of shale pressure diffusion was integrated with geomechanical simulations to assess the propagation of time shifts and time strain in the overburden of a high pressure/high temperature reservoir under compaction, improving the understanding of the distribution and polarity of the observed seismic time strain. Fluid flow simulation results of this work indicate that activation of the shale improves the overall reservoir connectivity, enhancing model prediction (production history matched data). The fit to observed 4D seismic data was improved in all the field applications with a noticeable reduction (up to 6%) in the mismatch (hardening and softening signal distribution) for the models with active shales. In reservoirs where the saturation was very sensitive to changes in pressure, shale activation proved to impact strongly on the breakout and distribution of gas liberated from solution. Overall, this work found that inclusion of shale in the 3D and 4D reservoir seismic modelling can provide valuable insights for the interpretation of the reservoir’s dynamic behaviour and that, under particular conditions such as strong reservoir compartmentalization, shale pressure diffusion could be a significant process in the interpretation of the 4D seismic signature.
15
Mauricio, Iglesias Miguel. "Impact of high pressure thermal treatments on food/packaging interactions." Montpellier 2, 2009. http://www.theses.fr/2009MON20225.
Повний текст джерелаАнотація:
La maîtrise des interactions aliment/emballage est essentielle pour assurer la sécurité et la qualité des produits emballés. Dans le cadre du Projet Européen Novel Q, nous avons évalué l'impact des traitements de hautes pressions thermales (HP/T) sur les interactions aliment emballage. En particulier, nous avons étudié l'effet d'une pasteurisation (800 MPa, 5 min, 40°C) et une stérilisation (800 MPa, 5 min, 115°C) haute pression sur la migration et le scalping du polyéthylène linéaire de basse densité (LLDPE), du polylactate (PLA) et d'un nanocomposite biodégradable à base de gluten de blé/montmorillonite (WG/MMT). Pour LLDPE et PLA, la caractérisation de la migration s'est basée dans le suivi de deux additifs modèles, Uvitex OB et Irganox 1076 alors que pour le WG/MMT d'autres tests additionnels ont été faits, i. E. Migration globale, des protéines et de nanoparticules. Les traitements HP/T n'ont pas eu un effet significatif sur la plupart d'interactions étudiées sauf pour la migration de nanoparticules du WG et lors du scalping à haute température. Jusqu'à présent, les méthodes le plus fréquemment utilisées pour la détermination de niveaux de migration sont basées dans la destruction et quantification de l'échantillon, s'avérant de méthodes longues et coûteuses. Pour s'affranchir de telles méthodes, la modélisation a été récemment acceptée en tant que méthode d'estimation de migration. Néanmoins, les paramètres nécessaires, c'est-à-dire, la diffusivité et le coefficient de partage ne sont que rarement connus. L'utilisation de la spectroscopie Raman et FTIR pour déterminer des niveaux de migration et surtout, pour estimer la diffusivité d'un additif dans du LLDPE s'est accomplie avec succès, permettant une caractérisation complète du transfert de matière dans le systèmeThe control of food/packaging interactions is essential to ensure the safety and quality of packed products. In particular, in the framework of the European Project Novel Q (IP6, Novel Processing Methods for the Production and Distribution of High Quality and Safe Foods), the effect of high pressure thermal (HP/T) treatments on food/packaging interactions was assessed in a variety of cases. Migration and scalping were studied for linear low density polyethylene (LLDPE), polylactide (PLA) and a wheat gluten/montmorillonite (WG/MMT) nanocomposite novel biodegradable and nanocomposite materials in food simulating liquids (FSL). Food/packaging interactions were studied after two HP/T treatments intended to perform a pasteurization (800 MPa, 5 min, 40°C) and a sterilization (800 MPa, 5 min, 115°C) treatment, as well as subsequent storage for 10 days. Specific migration of an additive (Uvitex OB) was assessed for LLDPE and PLA, whereas additional tests were carried out for WG/MMT, i. E. Overall migration, protein migration and nanoparticles migration. HP/T treatments did not significantly modify the migration or scalping in the conditions studied except for the release of nanoparticles from WG. Interestingly, the increase in the melting point of LLDPE during HP/T made possible to sterilize it. To date the most frequently used methods in migration assessment are based in time consuming methods based on destruction and quantification. To avoid them, modeling has been recently approved as a method for migration assessment. However, the parameters needed, i. E. Diffusivity (D) and the partition coefficient (K) are seldom available. The use of FTIR and Raman spectroscopy to assess migration behavior and, more importantly, to determine the diffusivity of an additive in LLDPE was successfully carried out allowing a complete characterization of mass transfer
16
Volk, Stephanie Paige. "Impact of high-pressure processing on soy and egg proteins." [Ames, Iowa : Iowa State University], 2009. 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:1473269.
Повний текст джерела
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Kingsbury, Adam. "Examining the Impact of Social Pressure on Golf Putting Performance." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40027.
Повний текст джерелаАнотація:
Fine-motor skills in any domain (e.g., sports, surgery, music) are subject to performance decrements under pressure. A large majority of studies that have examined “choking under pressure” used golf putting as a paradigm to test participants. Golf putting is a fine-motor skill that is highly susceptible to deviations in performance, yet a skill that appears to be deceptively simple without a steep learning curve. The following thesis contained three studies that examined the influence of social evaluative threat on the objective outcome performance (holed or not holed, distance to the hole), as well as the kinematic variables associated with the putting stroke itself. Performance was measured using a high-speed infrared camera called the TOMI® which collected real-time 3D data about a number of different kinematic parameters for each putt that was struck. While it was expected that a learning effect would characterize the longitudinal trajectory of performance, it was also expected that state anxiety would moderate this trajectory.
In Study 1, 35 amateur golfers, completed a self-report measure of state anxiety and performed golf putting tasks under a neutral condition followed by a social-evaluative condition. Somatic anxiety was related to differential performance trajectories, while cognitive anxiety was associated with variability in the backstroke. In Study 2, 27 beginner participants participated in an improved design based on Study 1. Somatic anxiety temporarily moderated performance under pressure for the novices. In Study 3, 55 beginner participants were recruited and randomized to either a stress-free learning task (n = 29), or a social-evaluative learning task (n = 26), to address research limitations from the first two studies. Furthermore, methodological concerns present in both Study 1 and 2 were addressed, with the aim of contributing to the debate surrounding theoretical mechanisms of how performance decrements occur, specifically under social-evaluative threat. High levels of somatic anxiety moderated the objective performance trajectory of the experimental group, and surprisingly decreased the amount of time taken to prepare for each putt in the social-evaluative task.
In all three studies, somatic anxiety significantly moderated both objective and indirect performance (as indicated by kinematics and routine time). Taken together, these studies suggest that one’s interpretation of physiological symptoms while under social evaluative threat can temporarily impair performance trajectories of a fine-motor skill.
18
Fowler, Robin. "The impact of elevated pulmonary artery pressure on exercise responses." Thesis, Curtin University, 2012. http://hdl.handle.net/20.500.11937/2637.
Повний текст джерелаАнотація:
Background and research questions. The four studies reported in this thesis investigated the implications of an elevated pulmonary artery pressure (PAP) on the response to an exertional challenge. The level of symptoms and exertion that healthcare professionals consider appropriate for patients with pulmonary arterial hypertension (PAH) was explored in the first study. In studies two, three, and four, exercise responses and exercise testing were evaluated in individuals with an elevated PAP on exercise, but a normal PAP at rest (exercise-induced pulmonary arterial hypertension, [EIPAH]).The following research questions were addressed: 1. Is there consistency in the advice given by healthcare professionals in Australia regarding physical exertion and symptoms, and in referral for exercise rehabilitation, for patients with PAH? 2. What are the clinical implications of an elevated PAP in symptomatic individuals with risk factors for PAH but who have a normal PAP at rest (EIPAH)? 3. Can the six-minute walk test (6MWT) identify reduced exercise capacity and accurately estimate aerobic capacity in individuals with EIPAH? 4. Are the haemodynamic and symptomatic responses to maximal and submaximal resistance exercise similar to the responses demonstrated during comparable intensities of aerobic exercise in individuals with EIPAH?Abstracts for the reported studies. This PhD program formed the basis for four publications in peer reviewed, international, scientific journals. These four publications are summarised, in abstract form, below. The full manuscripts of these publications constitute Chapters 4-7 of this thesis.
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Tomko, Matthew. "Impact of Purge Flow Variation On Rotor Cavity and Blade Platform Pressures For A Transonic High-Pressure Turbine." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1452097558.
Повний текст джерела
20
Ashford, Kelly J. "Dispositional self-focus and its impact on skill execution under pressure." Thesis, Brunel University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422408.
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Fletcher, Helen. "The impact and management of visitor pressure on Rocky Shore communities." Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363528.
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Rochette, P., G. Fillion, R. Ballou, F. Brunet, B. Ouladdiaf, and L. Hood. "High pressure magnetic transition in pyrrhotite and impact demagnetization on Mars." AMER GEOPHYSICAL UNION, 2003. http://hdl.handle.net/10150/623401.
Повний текст джерелаАнотація:
Using neutron diffraction under pressure at room temperature, we observed that pyrrhotite undergoes a ferrimagnetic to paramagnetic transition at about 2.8 GPa. Complete demagnetization of remanence at the same pressure is confirmed in an independent experiment. Such a process provides a quantitative explanation of the magnetic structure of the Martian Southern Hemisphere assuming that pyrrhotite is the major magnetic mineral and that our static experiments can be extrapolated to dynamic pressure conditions. Indeed, the 3 GPa isobaric line during the two large impacts of Argyre and Hellas separates the magnetized and unmagnetized zones. We also infer a reinterpretation of Martian meteorites paleomagnetic signal.
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Gao, Fan. "The Impact Dynamics of Weakly Charged Droplets." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/92888.
Повний текст джерелаАнотація:
Electric charges are often found in naturally or artificially formed droplets, such as raindrops and those generated by Kelvin's water dropper. In contrast to the impact of neutral droplets on a flat solid surface upon which a thin convex lens shape layer of the gas film is typically formed, I show that the delicate gas thin film can be fundamentally altered for even weakly charged droplets both experimentally and numerically. As the charge level is raised above a critical level of about 1% of the Rayleigh limit for representative impact conditions, the Maxwell stress overcomes the gas pressure buildup to deform the droplet bottom surface. A conical liquid tip forms and pierces Through the gas film, leading to a circular contact line moving outwards that does not trap any gas. The critical charge level only depends on the capillary number based on the gas viscosity. The deformation applies to common liquids and molten alloy droplets. Even dielectric surfaces can also induce conical deformation. The charged droplets can also deform upon hydrophobic surfaces, and increase the contact time on hydrophobic surfaces or even avoid bouncing.Doctor of Philosophy
Electric charges are often found in naturally or artificially formed droplets, such as raindrops, waterfall, and inkjet printer. Neutral droplets impact on flat surfaces will usually trap a bubble inside because of the viscosity of air. The air bubble entrapped can be ignored if the droplet is water because the air bubble will eventually pinch-off. However, if the droplet is metal or some other viscous liquid, the air bubble will stay inside the liquid. This entrapped air bubble is undesired under some circumstances. For example, the existence of air bubble during metal 3D printing can influence the physical property. I show that the delicate gas thin film can be fundamentally altered for even weakly charged droplets both experimentally and numerically. As the charge level is raised above a critical level of about 1% of the maximum charges a droplet can carry for representative impact conditions, the electric stress will dominate the deformation of droplet. A conical liquid tip forms at the droplet bottom, avoiding the entrapment of air bubble. The critical charge level is experimentally proved to be only dependent on the gas viscosity and impact velocity. The deformation applies to common liquids and molten alloy droplets. Even dielectric surfaces can also induce conical deformation. The charged droplets can also deform upon hydrophobic surfaces, and increase the contact time on hydrophobic surfaces or even avoid bouncing.
24
Maley, Lisa. "A study of slug flow characteristics in large diameter horizontal multiphase pipelines." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1177090588.
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25
Sparks, Jessica L. "Biomechanics of blunt liver injury relating internal pressure to injury severity and developing a constitutive model of stress-strain behavior /." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1185909955.
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DHANORE, NISHANT. "Impact of Pressure Pulsations on Diesel Air Path Control and Compensation Measures." Thesis, KTH, Maskinkonstruktion (Avd.), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-251023.
Повний текст джерелаАнотація:
Stricter pollution norms have led to increased efforts to achieve lower emissions. Exhaust Gas Re-circulation (EGR) is a well known measure to reduce NOx internally in the engine. In order to achieve better performance of an engine in terms of emissions it is very essential to control the flow of exhaust gases through EGR valve. Generally, an Engine Control Unit (ECU) uses mean value models or map-based approaches to calculate the mass flow through EGR valve. The main driving factor of the mass flow through an EGR valve i.e. the exhaust gas pressure is continuously fluctuating throughout an engine cycle. This continuous change in the pressure lead to variations in the mass flow through EGR valve, thus introducing inaccuracies in the desired flow through EGR valve, thereby affecting the engine performance greatly. Hence it is very essential to consider the pulsations in a combustion cycle. In this thesis an EGR valve model is developed in Matlab/Simulink environment. The model is able to consider the effect of exhaust pressure pulsations and is found to be more accurate than the mean value models used in the ECU.
27
Schaner, Jason. "The impact of nanoclay addition on PVC pressure-sensitive digital printed films." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1541870409272098.
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28
Ahmad, Mansoor. "Experimental assessment of droplet impact erosion of low pressure steam turbine blades." Aachen Shaker, 2009. http://d-nb.info/998626953/04.
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29
Ng, Fu Liang. "The impact of the blood pressure-associated genetic locus at SLC4A7 on gene expression and intracellular pH regulation." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24732.
Повний текст джерелаАнотація:
Genome-wide association studies have revealed an association between variation at the SLC4A7 locus and blood pressure. SLC4A7 encodes the electroneutral Na+/HCO3 - co-transporter NBCn1 which regulates intracellular pH (pHi) in a range of tissues, including vascular smooth muscle and endothelium. Notably, the SLC4A7 knockout mouse has been shown to have an altered blood pressure phenotype. This thesis presents a functional study of variants at this locus in primary cultures of vascular smooth muscle and endothelial cells. There were genotype-dependent differences in DNA-nuclear protein interactions by formaldehyde-assisted isolation of regulatory elements, electrophoretic mobility shift assays and DNA pulldown assays. Subsequently, there were also genotypedependent differences in SLC4A7 expression level and NBCn1 availability at the plasma membrane. In turn, SLC4A7 genotype is associated with Na+/HCO3 --dependent steady-state pHi and recovery from intracellular acidosis. The genotypic effect on pHi regulation was independent of the calcineurin activity, or the amino acid substitution E326K resulting from a missense polymorphism. However, in the presence of Na+/H+ exchange activity, the SLC4A7 genotypic effect on net base uptake and steady-state pHi was detected only in vascular smooth muscle cells but not endothelial cells. The finding of a genotypic influence on SLC4A7 expression and pHi regulation in vascular smooth muscle cells provide an insight into the molecular mechanism underlying the association of variation at the SLC4A7 locus with blood pressure.
30
Dutton, Andrew Geoffrey. "The determination of dynamic initiation fracture toughness of metals using the Hopkinson pressure bar loaded instrumented Charpy test." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280841.
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31
Burston, Sarah elizabeth Ann. "Assessing the Impact of a Transforming Care Initiative in the Australian Context." Thesis, Griffith University, 2015. http://hdl.handle.net/10072/365358.
Повний текст джерелаАнотація:
Hospitalised patients experience harm as a consequence of adverse events, including inpatient falls and hospital-acquired pressure ulcers. Nurses are attempting to address this situation with the development of international initiatives aimed at improving the safety and quality of nursing care. Evidence to support the implementation of these initiatives is limited, yet widespread implementation continues.
The aim of this study was to understand the implementation, impact and sustainment of an initiative to transform nursing care in four acute medical-surgical units. The focus of the initiative was to provide a patient centred framework to improve the safety and quality of nursing care. A number of interventions were implemented such as clinical bedside handover and rounding.
This study was conducted in two phases. Phase One used a non-equivalent control group design with historical controls and an uncontrolled interrupted time series. More than 10,000 patients discharged between July 2008 and December 2010 were included. Patients discharged during the initial three months of implementation, were excluded. Two nurse-sensitive indicators were used as outcome measures; inpatient falls and hospital-acquired pressure ulcers. Coded administrative data were analysed using statistical process control to identify changes in the nurse-sensitive indicators over time.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Nursing and Midwifery
Griffith Health
Full Text
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Ni, Huan Jie. "The impact of peer association on juvenile delinquency among Chinese adolescents." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3953672.
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SWANSON, LUKE A. "A DETAILED EXAMINATION OF THE PRESSURE PRODUCED BY A HYDRODYNAMIC RAM EVENT." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1195587339.
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34
Gorbach, Andreas [Verfasser]. "Compact Rapid Pressure Swing Adsorption Processes – Impact of Novel Adsorbent Monoliths / Andreas Gorbach." Aachen : Shaker, 2006. http://d-nb.info/1170529380/34.
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35
Wolters, G. "Characteristics of wave impact induced pressure pulse propagation into cracks of coastal structures." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419521.
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36
Neidel, Tobias, Nicolas Salvador, and Axel R. Heller. "Impact of systolic blood pressure limits on the diagnostic value of triage algorithms." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-231546.
Повний текст джерелаАнотація:
Background
Major incidents are characterized by a lack of resources compared to an overwhelming number of casualties, requiring a prioritization of medical treatment. Triage algorithms are an essential tool for prioritizing the urgency of treatment for patients, but the evidence to support one over another is very limited. We determined the influence of blood pressure limits on the diagnostic value of triage algorithms, considering if pulse should be palpated centrally or peripherally.
Methods
We used a database representing 500 consecutive HEMS patients. Each patient was allocated a triage category (T1/red, T2/yellow, T3/green) by a group of experienced doctors in disaster medicine, independent of any algorithm. mSTaRT, ASAV, Field Triage Score (FTS), Care Flight (CF), “Model Bavaria” and two Norwegian algorithms (Nor and TAS), all containing the question “Pulse palpable?”, were translated into Excel commands, calculating the triage category for each patient automatically. We used 5 blood pressure limits ranging from 130 to 60 mmHg to determine palpable pulse. The resulting triage categories were analyzed with respect to sensitivity, specificity and Youden Index (J) separately for trauma and non-trauma patients, and for all patients combined.
Results
For the entire population of patients within all triage algorithms the Youden Index (J) was highest for T1 (J between 0,14 and 0,62). Combining trauma and non-trauma patients, the highest J was obtained by ASAV (J = 0,62 at 60 mmHg). ASAV scored the highest within trauma patients (J = 0,87 at 60 mmHg), whereas Model Bavaria (J = 0,54 at 80 mmHg) reached highest amongst non-trauma patients. FTS performed worst for all patients (J = 0,14 at 60 mmHg), showing a lower score for trauma patients (J = 0,0 at 60 mmHg). Change of blood pressure limits resulted in different diagnostic values of all algorithms.
Discussion
We demonstrate that differing blood pressure limits have a remarkable impact on diagnostic values of triage algorithms. Further research is needed to determine the lowest blood pressure value that is possible to palpate at a peripheral artery compared to a central artery.
Conclusion
As a consequence, it might be important in which location pulses are palpated according to the algorithm at hand during triage of patients.
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Trupp, Robin J. "The Impact of Message Framing on Adherence to Continuous Positive Airway Pressure Therapy." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1228151374.
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Neidel, Tobias, Nicolas Salvador, and Axel R. Heller. "Impact of systolic blood pressure limits on the diagnostic value of triage algorithms." BioMed Central, 2017. https://tud.qucosa.de/id/qucosa%3A30689.
Повний текст джерелаАнотація:
Background
Major incidents are characterized by a lack of resources compared to an overwhelming number of casualties, requiring a prioritization of medical treatment. Triage algorithms are an essential tool for prioritizing the urgency of treatment for patients, but the evidence to support one over another is very limited. We determined the influence of blood pressure limits on the diagnostic value of triage algorithms, considering if pulse should be palpated centrally or peripherally.
Methods
We used a database representing 500 consecutive HEMS patients. Each patient was allocated a triage category (T1/red, T2/yellow, T3/green) by a group of experienced doctors in disaster medicine, independent of any algorithm. mSTaRT, ASAV, Field Triage Score (FTS), Care Flight (CF), “Model Bavaria” and two Norwegian algorithms (Nor and TAS), all containing the question “Pulse palpable?”, were translated into Excel commands, calculating the triage category for each patient automatically. We used 5 blood pressure limits ranging from 130 to 60 mmHg to determine palpable pulse. The resulting triage categories were analyzed with respect to sensitivity, specificity and Youden Index (J) separately for trauma and non-trauma patients, and for all patients combined.
Results
For the entire population of patients within all triage algorithms the Youden Index (J) was highest for T1 (J between 0,14 and 0,62). Combining trauma and non-trauma patients, the highest J was obtained by ASAV (J = 0,62 at 60 mmHg). ASAV scored the highest within trauma patients (J = 0,87 at 60 mmHg), whereas Model Bavaria (J = 0,54 at 80 mmHg) reached highest amongst non-trauma patients. FTS performed worst for all patients (J = 0,14 at 60 mmHg), showing a lower score for trauma patients (J = 0,0 at 60 mmHg). Change of blood pressure limits resulted in different diagnostic values of all algorithms.
Discussion
We demonstrate that differing blood pressure limits have a remarkable impact on diagnostic values of triage algorithms. Further research is needed to determine the lowest blood pressure value that is possible to palpate at a peripheral artery compared to a central artery.
Conclusion
As a consequence, it might be important in which location pulses are palpated according to the algorithm at hand during triage of patients.
39
Swantek, Steven David. "An Optical Method of Strain Measurement in the Split Hopkinson Pressure Bar." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/34711.
Повний текст джерелаАнотація:
The split Hopkinson pressure bar (SHPB) continues to be one of the most common methods of testing materials at medium rates of strain. Elevated rates of strain, such as those found in impact and explosive applications, have been shown to induce phenomena such as strain hardening and phase transitions that can significantly affect the strength of most materials [14]. Due to its relative simplicity and robustness, the SHPB remains one of the preferred platforms for evaluating mechanical properties of materials at rates of strain up to approximately 104 in/in-s (s-1). At the Naval Surface Warfare Center Dahlgren Division (NSWCDD), research has been conducted in which a semiconductor laser diode has been used to measure the radial strain of a plastically deforming cylindrical test specimen in the SHPB.
The SHPB consists of two long, slender cylindrical bars, denoted input and output bars, that "sandwich" a cylindrical test specimen. Utilizing a high-pressure gas gun, a third cylindrical steel bar, known as the striker bar, is fired at the input bar, causing a compressive stress wave to travel through the input bar to the input bar - test specimen interface. At this interface, a portion of the stress wave propagates through the test specimen while the remainder of the pulse reflects back through the input bar as a tensile stress wave. The non-reflected portion of the stress pulse transmits through the test specimen and into the output bar causing the specimen to deform both elastically and plastically. Strain gages mounted to the input and output pressure bars measure both the incident, transmitted and reflected pulses. Specimen stress can be calculated using the transmitted strain signal while specimen strain and strain rate can be computed using the reflected strain pulse.
In order to measure the specimen strain directly, a 670-nm wavelength semiconductor laser diode was affixed to the SHPB such that a vertical line of light approximately 250 micrometer (µm) wide was generated across the diameter of the test specimen. A collector lens located aft of the specimen was positioned to collate the light not occluded by the diameter of the specimen and refocus the light to be collected by a 25 MHz photodetector. Thus, changes in specimen diameter due to the impact event would result in more light being occluded by the specimen and less spectral energy being collected by the photodetector. The light collected by the photodetector is then converted to a voltage output before being recorded by a digital storage oscilloscope. With a known voltage-to-diameter calibration relationship, medium strain rate compressive tests were conducted to compare the optically measured strain results with the data gathered with the existing strain gages.
It was found that the optical measurement system provided increased bandwidth and greater resolution than the conventional strain gage instrumentation while generating strain and strain rate results within 6.7% of corresponding strain gage data. This increased bandwidth and resolution allows the identification of both the elastic and plastic behavior of the specimen. In addition, the loading and unloading of the specimen can be clearly seen in the optical strain signal. These phenomena are evident in the peak diameter and strain achieved by the specimen, data not previously available with strain gage instrumentation. The plastic modulus, the theoretical relationship between the stress and strain in the plastic regime, also exhibits a significant increase in magnitude due to this ability to measure peak rather than average strain. Finally, by ridding the experiment of the input bar strain gage, input bar dispersion and the electrical and mechanical errors associated with the input bar strain gage were nullified. These conclusions will be validated through the presentation of several sets of experimental data correlated to data gathered previously.Master of Science
40
Clark, Eric A. "The Cryogenic Bonding Evaluation at the Metallic-Composite Interface of a Composite Overwrapped Pressure Vessel with Additional Impact Investigation." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/521.
Повний текст джерелаАнотація:
A bonding evaluation that investigated the cryogenic tensile strength of several different adhesives / resins was performed. The test materials consisted of 6061 aluminum test pieces adhered to a wet-wound graphite laminate in order to simulate the bond created at the liner-composite interface of an aluminum lined composite overwrapped pressure vessel. It was found that for cryogenic applications, a flexible, low modulus resin system must be used. Additionally, the samples prepared with a thin layer of cured resin - or prebond - performed significantly better than those without. It was found that it is critical that the prebond surface must have sufficient surface roughness prior to the bonding application. Also, the aluminum test pieces that were prepared using a surface etchant slightly outperformed those that were prepared with a grit blast surface finish and performed significantly better than those which had been scored using sand paper to achieve the desired surface finish. An additional impact investigation studied the post impact tensile strength of composite rings in a cryogenic environment. The composite rings were filament wound with several combinations of graphite and aramid fibers and were prepared with different resin systems. The rings were subjected to varying levels of Charpy impact damage then pulled to failure in tension. It was found that the addition of elastic aramid fibers with the carbon fiber mitigate the overall impact damage and drastically improve the post impact strength of the structure in a cryogenic environment.
41
Ashton, J. "A qualitative study of the impact of pressure sores on patients' quality of life." Thesis, University of Salford, 2008. http://usir.salford.ac.uk/26553/.
Повний текст джерелаАнотація:
Pressure ulcers are known to be costly for the healthcare system and delay recovery in many patients. As research continues to highlight the cost of pressure ulcers in humanitarian and financial terms, they are increasingly being used as a key quality indicator. Healthcare professionals and patients may make assumptions about what it must be like to experience a pressure ulcer. Understanding the phenomenon of living with a pressure ulcer is crucial to providing and planning care for the pressure ulcer patient and to enhancing the overall quality of life for these individuals. Pressure ulceration continues to be reported and discussed in the nursing literature whilst the methodological quality of some studies has been poor, there is no doubt that patients continue to suffer harm. One commonly implicated effect of pressure ulcers is a reduction in quality of life. This is believed to be due to factors such as increased pain, social exclusion, malodour and growing limitations on activity and mobility. This study aimed to explore how developing a pressure ulcer affected patients' quality of life. A qualitative approach in the style of phenomenology was used to explore and describe the, experiences of people who had endured an episode of an open pressure ulcer. A purposeful sample of fifteen participants (10 females and five males) were selected, age range: 45-89 years. All the fifteen patients recruited, had a new episode of either a sacral pressure ulcer, or heel ulceration, which was graded three to four using the European Pressure Ulcer Advisory Panel grading system. Although grade one and two pressure ulcers are more common, they are not usually referred to the Tissue Viability service as grade three and four are treated as clinical incidents which have to be referred to the Tissue Viability Service. Homogeneous sampling reduces variation and permits a more focused inquiry. For complete confidentiality pseudonym names were given to the participants. Pressure ulcers can result in great discomfort and pain for patients. Enabling respondents to talk freely about their experiences of developing a pressure ulcer, rich data were obtained that should be helpful in understanding the impact of developing a pressure ulcer on people's lives. As emerging themes were similar following data collection the researcher took the decision to stop interviewing at fifteen participants. Six major themes were identified in the study; all the participants had a very good understanding of how a pressure ulcer developed. Each patient could remember exactly when the ulcer developed even though in some cases this had been a long time ago. All the participants expressed feelings of anger and frustration at the impact of developing a pressure ulcer had on their lives.
42
Warner, Todd C. "The impact of trivial details and interrogation pressure on jurors' evaluations of retracted confessions." Virtual Press, 2007. http://liblink.bsu.edu/uhtbin/catkey/1365526.
Повний текст джерелаАнотація:
The present study examined jurors' evaluations of retracted confessions as a function of the amount of trivial detail within the confession and level of interrogation pressure. Participants in the experimental conditions read a transcript of a murder trial involving a suspect who confessed in a high-pressure or low-pressure situation and provided either a high or low amount of detail. A no-confession control version, in which the suspect denied all allegations against him, was also included in the study. Although one analysis suggested that a high-amount of detail within the confession might make it more likely that jurors would give higher estimates of guilt, it did not lead jurors to give more guilty verdicts. In contrast to previous findings, the presence of a confession did not make it more likely that a juror would render a guilty verdict or give higher estimates of guilt, as no difference was found between the experimental groups and the control group.Department of Psychological Science
43
Ahmad, Mansoor [Verfasser]. "Experimental assessment of droplet impact erosion of low-pressure steam turbine blades / Mansoor Ahmad." Aachen : Shaker, 2009. http://d-nb.info/1161302182/34.
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44
Dhakal, Santosh. "Impact of High Pressure Processing on Immunoreactivity and SomePhysico-chemical Properties of Almond Milk." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374017194.
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45
Reiter, E. Miranda. "The Impact of Social Support, Psychosocial Characteristics, and Contextual Factors on Racial Disparities in Hypertension." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/3087.
Повний текст джерелаАнотація:
Hypertension is a serious medical condition. Although men and women of all racial groups in the US suffer from high blood pressure, black women have the highest rates of hypertension. For instance, the age-adjusted prevalence of hypertension among black women ages 20 and over is 44.3, compared to 28.1 among white women, 40.5 among black men, and 31.1 among white men.
Past research has focused on SES and behavioral factors as potential explanations for blood pressure disparities between black and white women. But, even after controlling for such factors, considerable disparities remain. The goal of this research is to examine cultural and social factors that have been shown to increase blood pressure. Specifically, I examine social support, psychosocial characteristics, and contextual factors associated with race/ethnicity and hypertension, in hopes of explaining some of the disparities in high blood pressure between black and white women. iii
Using data from Waves I, III, and IV of the National Longitudinal Study of Adolescent Health (Add Health), I estimated a sequence of multinomial logistic regression models predicting prehypertension and hypertension in young adulthood. Cross-sectional models show that racial disparities in hypertension remain after controlling for social support, psychosocial characteristics, and contextual factors. In fact, the only covariate that substantially reduced the racial disparity in hypertension was body mass index (BMI), a fairly reliable measure of body fatness for most people. I also estimated a set of multinomial logistic regression models predicting odds of prehypertension and hypertension by adolescent and cumulative social support, as well as psychosocial, contextual, and behavioral factors. These models were included to determine if early life and/or cumulative factors and conditions would help explain racial blood pressure disparities not explained by adulthood factors. Findings show that none of the early life or cumulative social support, psychosocial, contextual, or behavioral factors helped to explain racial differences in prehypertension or hypertension. Even after controlling for these factors, black women are still 1.18 times more likely than white women to have prehypertension and over two times more likely to suffer hypertension.
Indeed, my findings indicate that, of the factors included in all these models, only race, age, and BMI were significant predictors of blood pressure. Also, BMI was the only factor to explain some of the disparities between black and white women. These results are similar to other studies that have examined racial health disparities, suggesting that simply being a black woman in US society may be unhealthy. The health effects of racism, discrimination, and other sources of stress faced disproportionately by black women are not easily measured by social science research, which is possibly why racial disparities in blood pressure have yet to be explained. Future research should also explore possible epigenetic effects introduced by the health conditions experienced by previous generations, as well as the influence of prenatal and early life environments.
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Alves, Fábio Rui Lima. "Traits of benthic assemblages subjected to different trawling pressure." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/12618.
Повний текст джерелаАнотація:
Mestrado em Biologia MarinhaOver time, fishing techniques improved as a response to the needs of Human populations. Alongside with the increase of fishing activities important changes in the marine ecosystems were also observed (e.g. overexploitation of stocks and habitat loss or degradation). Overfishing, bycatch, discards and ghost-fishing are some of the most discussed impacts of fishing activities, but the effect of bottom trawling should not be underestimated, since it has been proven to have a significant impact of benthic communities. Up to now the knowledge about fisheries impact on deep-sea benthic macrofaunal assemblages is scarce in Europe and, for all we know, even more in Portuguese fishery grounds. However, assessing fisheries impacts on marine ecosystems and ensuring fisheries sustainability is essential to achieve proper management of the sector and for the conservation of marine resources. In this context, the present study was carried out aiming to investigate the impact of continued trawling on benthic macrofaunal assemblages from deep muddy grounds of the burrowing crustacean Nephropsnorvegicus (Norway lobster) by comparing towed and untowed stations regarding their biodiversity, density, biomass, trophic structure, life style and body size spectra. Seven stations were studied along a transect of a highly Fished zone (Area 1, Stations 1 and 2), a Non-fished zone (Area 2, Stations 3, 4 and 5) and another Fished zone (Area 3, stations 6 and 7) during a cruise carried out in September 2012 onboard the RV Garcia del Cid (Consejo Superior de Investigaciones Cientificas) in the framework of the project IMPACT (Universidade do Algarve). In general Fished zones showed decreased heterogeneity and although the results of the multivariate analysis support a significant difference between Fished and Non-fished areas the comparisons of the biodiversity (number of families, H’, EF(n)), density and biomass in Fished and Non-fished zones are inconclusive, inconsistent or even contradict most of the literature predictions. When the trophic structure and life style spectra of the assemblages are compared the decreased heterogeneity of the Fished zones is confirmed but other patterns emerge such as the higher relative contribution of free living organisms, especially meiofaunal predators, grazers and browsers in Fished zones in contrast with the higher relative contribution of tubiculous animals in Non-fished zones, the dominance of deposit feeders over detritus feeders in Fished areas and the presence of large suspension feeders in Non-fished zones. The interpretation of the observed taxonomic and trophic structure of the assemblages is complex and must take into account sources of variability introduced by unwanted alterations of the sampling strategy and habitat heterogeneities in the study area. Overall this study constitutes a good asset for the knowledge of bottom trawling impact on macrofaunal assemblages from deep-sea habitats. It is at this point impossible to estimate the impact of 60 years of bottom trawling and regular monitoring studies are desirable. Some methodological issues arose which can be used as recommendations for future assessments of trawling impacts and monitoring of seafloor integrity: selection of adequate control area(s) must consider habitat heterogeneity, selection of the sampling gear must consider the possible selectivity of smaller samplers; the number of replicates per stations should be sufficiently large to ensure representativeness of biodiversity, abundance and biomass assessment and significance of the comparative tests; and finally, trophic structure, life style and body size spectra showed to be good indicators of change and therefore they should become a more common tool on the assessment of trawling impact.
Ao longo do tempo, as artes de pesca têm vindo a evoluir como resposta às crescentes necessidades da população Humana. Ao mesmo tempo que a indústria pesqueira tem vindo a crescer têm-se vindo a observar importantes mudanças nos ecossistemas marinhos (ex. sobreexploração de recursos pesqueiros e perda ou degradação da biodiversidade). A sobre-pesca, pesca de espécies acessórias, rejeições e pesca fantasma são os impactos causados pelas pescas que geram maior preocupação, mas o efeito devastador de pesca de arrasto no fundo oceânico não deve ser subestimado, devido ao seu reconhecido impacto nas comunidades bentónicas. Até aos dias de hoje o conhecimento acerca do impacto em comunidades bentónicas de mar profundo é escasso na Europa e ainda menor em fundos oceânicos Portugueses. Contudo, a avaliação dos impactos da indústria pesqueira em fundos marinhos e nos seus ecossistemas é essencial para obter uma gestão apropriada do setor e para um uso mais sustentável dos recursos biológicos. Neste contexto, este estudo tem como objectivo avaliar o impacto da contínua pressão das pescas de arrasto em comunidades de macrofauna bentónica em fundos lamosos de mar profundo nos habitats do crustáceo Nephrops norvegicus (Lagostim), através da comparação de fundos impactados com fundos nãoimpactados, considerando a análise da biodiversidade, densidade, biomassa, estrutura trófica, espectro de tamanhos e modos de vida. Foram estudadas sete estações ao longo de um transeto, das quais, as primeiras duas estações (estações 1 e 2, área 1) correspondem a uma zona impactada, as seguintes três estações a uma zona não sujeita a pesca de arrasto (estações 3, 4 e 5, área 2,) e, por fim, duas estações (estações 6 e 7, área 3) novamente sujeitas a pressões de pesca de arrasto. A expedição oceanográfica foi realizada em Setembro de 2012 a bordo do navio RV Garcia del Cid (Consejo Superior de Investigaciones Cientificas) inserido no projecto IMPACT (Universidade do Algarve). De um modo geral, as zonas pescadas mostram uma menor heterogeneidade e embora os resultados da análise multivariada suportem uma diferença significante entre zonas pescadas e não-pescadas, as comparações de biodiversidade (número de familias, H’, EF(n)), densidade e biomassa) em zonas pescadas e não-pescadas são inconclusivas, inconsistentes e por vezes contraditórias quando comparadas com a literatura. Quando a estrutura trófica e o estilo de vida das comunidades são comparados, a pequena heterogeneidade nas zonas pescadas é confirmada, mas outros factores emergem, como a contribuição de animais de mobilidade livre, especialmente predadores de meiofauna e raspadores em zonas pescadas, em contraste com a alta contribuição de animais tubículos em zonas não-pescadas, a dominância de detritívoros que se alimentam de matéria orgânica associada ao sedimento sobre detritívoros que se alimentam de matéria orgânica particulada, em zonas pescadas e a presença de grandes suspensívoros em zonas não-pescadas. A interpretação dos resultados taxonómicos e da estrutura trófica é complexa e deve ter em conta variações introduzidas por alterações não esperadas na estratégia de amostragem e diferenças de habitat das zonas estudadas. No geral, este estudo contribui para o conhecimento do impacto de pescas de arrasto em comunidades de macrofauna bentónica de ambientes marinhos profundos. Nestas condições é dificil avaliar quais os efeitos de 60 anos de pressões de pesca de arrasto e futuros estudos são desejáveis. Surgiram alguns problemas metodológicos, o que pode servir como recomendações para futuros estudos de impactos de pesca de arrasto e monitorização da integridade dos fundos oceânicos: uma boa selecção de áreas controlo deve ser considerada; a seleção de tipos de amostradores deve ter em conta a selectividade de amostradores menores; o número de réplicas por estação deve ser suficiente para garantir representatividade da biodiversidade, abundância e biomassa, e a significância de testes comparativos; e por fim, estrutura trófica, espetro de tamanhos e modo de vida mostraram ser bons indicadores de diferenças entre as duas zonas, logo deveriam ser usados mais regularmente na avaliação de impactos de pesca de arrasto.
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Matson, Erin L. Hockman. "The Impact of Cardiopulmonary Baroreceptors on Pain Perception in Individuals at Differing Risk for Hypertension." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1265743580.
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Kaya, Derya. "Effect Of Resin And Fiber On The Abrasion, Impact And Pressure Resistance Of Cylindrical Composite Structures." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613287/index.pdf.
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The aim of this study was to investigate the effects of resin and fiber on the abrasion, impact and internal pressure resistances of fiber reinforced plastic composite pipes produced by continuous filament winding method. For this study, pipe samples were produced with different combinations of resin type, fiber type, fiber amount and fiber length. All the samples were tested in accordance with the related ISO (International Organization for Standardization), DIN (German Standardization Institution) and BSI (British Standards Institution) standards. Three types of resins were used as ortophthalic, isophthalic and vinylestertwo types of fibers were used as E-glass and ECR-glass and one type of GLASSFLAKES was used as C-glass. It was observed that the type of resin did not have any significant effect on burst pressure. However, the vinylester resin had a considerable positive effect on the abrasion and impact resistances. Moreover, it was observed that the type of fiber did not have any significant effect on impact and internal pressure resistances, but the use of C-glass GLASSFLAKES resulted in a positive effect on the abrasion resistance. Additionally, it was found that the increase in the amount of glass fiber resulted in increase of burst pressure, impact and abrasion resistances. Finally, it was observed that the length of glass fiber did not have any significant effect on abrasion resistance, but the decrease in fiber length resulted in a higher internal pressure and impact resistances.
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Huang, Chunhua. "Impact of dietary salt intake during growth on cardiovascular homeostasis and neural control of the kidney : role of brain angiotensin II (Ang II)." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368519.
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Caivano, Antonio. "The impact of nutrients on microbial Hydrocarbon degradation at deep-sea Temperature and Hydrostatic Pressure." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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Currently available physical and chemical remediation technologies are not effective in the deep sea, where ultimate fate of oil is strongly dependent on degradation by microorganisms. In order to setup an efficient bioremediation strategy, the effect of the environmental constraints on oil degrading communities’ metabolism needs to be assessed.
In this work, natural surface seawater communities were incubated under different T, P and in different dilutions of the medium ONR7a. Then, after 1 day, 1 week and 3 weeks, cell number, SO4, NH4 and DIC concentration were assessed.
When only one environmental stress (low T or high HP) is applied, a positive effect of nutrients’ concentration is highlighted, with increased growth rates and DIC production; at 23 °C and 20 MPa, a lower cell growth is observed with respect to atmospheric pressure samples, but a relatively high value of oil degradation is mostly sustained by respiration to DIC: this result evidence the possibility to setup an effective biostimulation strategy in deep seas characterized by milder temperatures (Sulu, Mediterranean, Red Sea). High Ammonium concentrations are needed to sustain large production of proteins for cell maintenance process required for adaptation to HP. Moreover, at 23 °C and 20 MPa, significant Sulphate uptake occurs, whose role in HP adaptation needs to be clarified. Also at low T and atmospheric pressure oil biodegradation mostly relies on respiration to DIC, however biodegradation rates seems to be more affected by T reduction than HP increase.
When both low T and high HP are applied, cellular metabolism is still active but any growth is observed, drastically reducing the oil biodegradation, that relies only on respiration to DIC. Surface communities subject to combination of 2 stresses may need more than 3 weeks to adapt to the deep sea environment and start a growth phase.