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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Recovering Hyperbole: Re-Imagining the Limits of Rhetoric for an Age of Excess

Ritter, Joshua R 18 August 2010 (has links)
Hyperbole has a varied and contentious history, and its forms and functions are largely ignored and dismissed today. Often misunderstood, hyperbole nevertheless offers critical insights into our understandings of epistemology and ontology that cannot go unexplored. In order to recover and reinvigorate a theory of hyperbole within the field of rhetorical theory and criticism, I explore the history of this critical trope from ancient to modern times. I then offer two functions and one meta-function of hyperbole based on this historical survey: moving through impossibility towards possibility, asserting a lie on the side of truth(s), and re-orienting one’s perspective through disorientation. Derived from a historical survey of hyperbole, these two functions and one meta-function are vital for understanding and constructing a theory of hyperbole that is productive and useful for current theoretical discussion. Using these functions, I offer a variety of examples under the purview of the epideictic and grotesque genres and show how hyperbole might be employed within rhetorical theory and criticism. Overall, this project seeks to respond to the gap that exists within current rhetorical theory regarding hyperbole, to explore why hyperbole is often dismissed as a tropological expression of excess and exaggeration, and to revitalize interest in hyperbole for critical use in areas such as rhetoric, theology, and philosophy.
12

Structure and dynamics of fluids : from molecular to colloidal perspectives

Pond, Mark Jeffrey 12 October 2011 (has links)
Relationships between structure and dynamics have been well studied in molecular fluids, both in computer simulations and in experiments. However, the development of simple structure-dynamics relationships would also be useful in understanding colloidal fluids. Colloidal fluids display differentiated component dynamics, are made of polydisperse particles, have soft interactions and have a separation of length and time scales. In this dissertation work, we have used computer simulations to generalize some structure-dynamics scaling laws, originally formulated for molecular fluids, in a way that successfully accounts for these important aspects of colloidal suspensions. To begin, we examine a two-component mixture of ultrasoft Gaussian-core particles through molecular dynamics simulations. This fluid shows an anomalous dynamic crossover where the larger particles become more diffusive than the smaller particles. However, this dynamic crossover is accompanied by a corresponding structural crossover for a component-specific structural order metric. In the light of this structural order metric, the fluid is non-anomalous with respect to the relationship between static structuring and diffusivity. Next, we show that accounting for the many-component nature of even modestly polydisperse fluids is important for accurately characterizing their structure-dynamics relationships. We demonstrate this for colloids with short-range attractions through new Monte Carlo simulation techniques and through theoretical calculations carried out in the dilute limit. From here, we present a new generalized framework to non-dimensionalize diffusivity so that it will have an approximately one-to-one relationship with excess entropy. This method involves rescaling diffusivity with dilute-limit analyses that can be analytically and systematically executed. We tested this framework through a combination of molecular dynamics simulations, Brownian dynamics simulations and Monte Carlo simulations. The results of the simulations demonstrate that this framework can account for particle size asymmetry, particle additivity, interaction strength and some solvent effects. Finally, we present a new, simple equation that relates non-dimensionalized forms of diffusivity from molecular dynamics and Brownian dynamics simulations. This simple relationship is tested for inverse power law fluids, as well as a suite of ultrasoft fluids that show structural and dynamic anomalies. / text
13

Seasonal cold, blood pressure and physical activity in young and elderly subjects

Goodwin, James January 2000 (has links)
No description available.
14

Självförsvar mot självförsvar : Rätten att försvara sig mot icke brottsliga angrepp

Högman, Olle January 2014 (has links)
Uppsatsen fokuserar på just initialangriparens möjligheter att freda sig mot ett icke straffbart försvar som han själv har gett anledning till. Därav titeln: ”Självförsvar mot självförsvar. Rätten att försvara sig mot icke brottsliga angrepp”. Självförsvarsrätten innebär en rätt att just försvara sig, inte mer. Frågan är i vilken utsträckning det är motiverat att en angripare får utstå de direkta fysiska konsekvenserna av självförsvaret utan att ha rätt att försvara sig. I uppsatsen utredes i vilka situationer, på vilket sätt, med vilket rättsligt – och ideologiskt – stöd (1) kan och (2) bör en person som först attackerat någon kunna åberopa nöd respektive putativt nödvärn för att försvara sig ”tillbaka” mot ett icke brottsligt självförsvar.
15

Solvent adsorption in SFC : Adsorption of methanol under supercritical conditions / Lösningsmedelsadsorption i SFC

Edström, Emelie January 2015 (has links)
Chromatography is a widely used separation technique including many different modes, for example supercritical fluid chromatography (SFC) which uses a supercritical fluid as mobile phase. A supercritical fluid is achieved when a substance is subjected to a temperature and pressure above the critical point and the boundary between the liquid phase and gas phase is erased. The interest for SFC has increased in recent years, mainly for separation of chiral molecules in the pharmaceutical industry. What makes SFC interesting is that it is a quick, cost-efficient and green method. This is in part due to less organic solvent used in the mobile phase in SFC compared with liquid chromatography and that the carbon dioxide that represents the major part of the mobile phase is a by-product from other processes. In SFC modifiers, often small alcohols, are added to carbon dioxide based mobile phase in order to increase the solubility of polar compounds. In this study the adsorption of methanol to two different stationary phases; Kromasil-Diol and chiral Lux Cellulose-4 were studied. Adsorption is a phenomenon where surface interactions crate a higher density of molecules at the surface than in the bulk. The aim of this work has been to study the adsorption of modifier (methanol) to the stationary phase both to determine the extent of adsorption and the kinetics for system equilibration. These findings were then put into perspective of normal use of SFC for separation of molecules. There are a number of techniques for measuring adsorption; in this study the tracer pulse method is used. This is a pulse method where a concentration plateau is created and an isotope labelled molecule is injected. This was performed in the mobile phase composition from pure carbon dioxide to pure methanol. In addition to the tracer pulse experiments the isotope effect, the eluent flow, equilibration times for the column and retention times for a set of analytes were measured. For the Diol column no large isotope effect was observed, the method was also proved to be highly reproducible since several runs gave consistent results. Calculations based on the experimental data showed that a 6.3 Å thick layer was built up at a methanol fraction of 13% (v/v), corresponding to a monolayer. Changes of the methanol fraction below the saturation level has has greater effect on the retention factor for the analytes than at higher methanol fractions, when the monolayer was saturated. The conclusion of this is that SFC is more stable in the area where the layer has been built up. A preliminary study has been made for the chiral Lux Cellulose-4 column which was not as conclusive as for the Kromasil-Diol column. This type of column needs further studies to confirm the deviating observations and to investigate the cause for these.
16

Polycystic ovary syndrome: role of androgen excess self-assessment in diagnosis

Karanja, Pascaline Wanjiru 14 June 2019 (has links)
BACKGROUND: Polycystic ovary syndrome is the most common endocrine disorder affecting reproductive-aged women. It is diagnosed using a combination of menstrual irregularity, clinical and/or biochemical hyperandrogenism and polycystic ovary morphology upon ultrasound. Hyperandrogenism in females may clinically manifest as hirsutism, acne, alopecia, or other masculinization of features. Assessing total/free testosterone, dehydroepiandrosterone sulfate, and 17-hydroxyprogesterone provides biochemical evidence of hyperandrogenism. OBJECTIVE: To determine self-reported clinical signs of androgen excess using data from the Ovulation and Menstruation Health (OM) Study, a diverse, multi-ethnic cohort study being conducted at Boston University School of Medicine. METHODS: Data was collected from participants enrolled in the Ovulation and Menstruation Health Study pilot cohort. This epidemiologic survey captured demographics, menstrual cycle patterns, PCOS histories, reproductive histories and manifestations of androgen excess in a diverse patient population. Participants were women ages 18-45 who had the capacity to ovulate/menstruate at the time of the study, had no history of chemotherapy, radiation, or surgical menopause, and were not pregnant at the time of the study. To assess androgen excess, participants were asked to self-report hair growth in nine body areas, acne on the face and back and hair loss on the scalp. The nine body areas were scored using the modified Ferriman-Gallwey (mFG) scoring system. Reference images created by a medical illustrator were used for hirsutism and alopecia grading while clear descriptions were provided for grading acne severity. Clinical hirsutism was defined as total mFG score of ≥ 8, or ethnic specific cutoff for East Asian (≥ 2) and Southeast Asian (≥ 3) women. Alopecia was defined as scalp hair loss ≥ 2. For participants that consented to medical record validation total, free and bioavailable testosterone lab levels were assessed for biochemical hyperandrogenism evaluation. RESULTS: Beginning August 9, the day the study opened to the public, 249 participants completed the pilot survey questionnaire. These participants were 66.8% white (n=165), 6.5% Hispanic or Spanish origin (n=16), 10.5% Black or African-American (n=26), 1.6% East Asian (n=4), 2.0% Southeast Asian (n=5), 2.4% South Asian (n=6), and 10.9% were of mixed ethnic backgrounds (n=27). 22.5% (55/245) of these women had clinical hirsutism by total mFG score. Mean total mFG scores were highest in women who were South Asian at 13.8±9.1 (n=6) and Hispanic at 8.6±8.7 (n=16). Moderate-severe acne was reported in 23.6% (58/246) of respondents, 24.8% (41/165) of white women, 26.7% (4/15) of Hispanic women, 15.4% (4/26) of Black women, 0.0% (0/4) of East Asian women, 20.0% (1/5) of Southeast Asian women, 50% of South Asian women (3/6) and 20% (5/25) of women of mixed ethnicities. 9.4% (23/246) of all pilot women reported alopecia, highest in Black (26.9%, 7/26) and East Asian women (25%, 1/4). Among women that had a PCOS diagnosis there was a higher presence of clinical hirsutism, higher acne severity, and higher prevalence of alopecia when compared to non-PCOS women. In addition, 33%(4/12) of the 44 women that consented to medical record validation had total testosterone levels above the normal range. CONCLUSIONS: This pilot population demonstrated an ethnic dependent pattern of development for hirsutism, acne and alopecia. Additionally, women who had a PCOS diagnosis were more likely to report having the clinical signs of androgen excess than those without a diagnosis. / 2020-06-14T00:00:00Z
17

Estimating recreational value of water quality in Mississippi lakes when water quality data are scarce

Kelsoe, Caroline 09 August 2019 (has links)
In its 2012 National Lakes Assessment, the EPA determined that nutrients are the most widespread stressor of US Lakes, with one-third of US lakes containing excess nitrogen and/or phosphorus. In response, states are developing numeric nutrient criteria to regulate the allowable amount of nutrients in surface waterbodies. In this study, we estimate the recreational value of improved water quality as a result of reduced nutrients in Mississippi lakes using a travel cost model. A major challenge, however, is the lack of water quality data for many Mississippi lakes. We introduce a water quality prediction model to impute water quality measures for lakes that lack water quality data. We compare welfare estimates from travel cost models based on the limited available water quality data to models using predicted water quality measures to evaluate the extent to which inadequate data affects welfare estimates for improved water quality.
18

Adsorption of supercritical carbon dioxide on microporous adsorbents: experiment and simulation

Gao, Weihong 24 August 2005 (has links)
No description available.
19

Economic and Environmental Analysis of Excess Heat at Pulp Mills

Kullmann, Felix January 2018 (has links)
European industries have realized that a reduction of primary energy usage is not only a European requirement but can also be of great economic interest. Especially both energy and resource intensive industries like the pulp and paper industry will benefit. Industrial excess heat as a by-product of industrial processes needing energy has a great potential to be a key factor in reducing primary energy usage. Both excess heat utilization and heat integration are potential ways for Kraft pulp mills to increase their energy efficiency, to decrease their primary energy use and thus green-house gas emission, and to support the pulp and paper industry to achieve sustainability goals and meet EU regulations. This thesis examines the total excess heat potential in the Swedish Kraft pulp industry through pinch analysis and optimization on a modelled average Swedish Kraft pulp mill (FRAM). Different excess heat recovery technologies (EHRTs) are identified based on their applicability and are evaluated regarding their environmental and economic benefits for the Swedish pulp industry by using the energy price and carbon scenarios tool (ENPAC tool). An excess heat potential in the Swedish Kraft pulp mill industry of 2,03 TWh at 60°C, and 3,53 TWh at 25°C is found in this study. Heat delivery to the district heating network (DH), cooling delivery to the district cooling network (DC), electricity generation with a condensing turbine (CT), phase-change material engine (PCM) and organic Rankine cycle (ORC) are identified as suitable excess heat recovery technologies for Swedish Kraft pulp mills. A payback time calculation in this study found the condensing turbine as the EHRT to be of highest economic benefit in 2018 (less than 3 years). With predicted future energy prices of the years 2030, 2040 and 2050 all considered recovery technologies become economically feasible (payback time of less than 3 years). The CT and combinations of CT with DH and DC are furthermore the recovery technologies with the highest CO2 savings of 100.000 t/a in 2018. All in all, this study suggests investing in a CT, or combinations of it with DH and DC, to create the greatest economic and environmental benefits in 2018. With future price changes on the energy market and an uncertain future energy demand an investment in combinations of recovery technologies generating both heat, cooling and electricity is found to be the most sustainable choice.
20

Electrochemical and infrared studies of the electrosorption of 4-methoxypyridine on crystallographic surfaces of gold.

2016 February 1900 (has links)
A firm knowledge about the interaction between the metal surface and adsorbed molecules is imperative for formulating procedures to synthesize nanoparticles (NPs) with predetermined shape and size. The ligand‐metal interaction during NP formation can be mimicked on an electrode surface by electrosorbing ligand molecules on a charged metal surface. Electrochemical methods can provide an ideal platform to study the adsorption behaviour of molecules at the solid‐liquid interface. In addition to classical electrochemical techniques, the combination of spectroscopy with electrochemical methods amplifies mechanistic insights about the surface adsorption processes. The adsorption behaviour of pyridine and one of its derivatives, 4‐dimethylamino pyridine (DMAP) have been well studied due to their potential application in nanoparticle synthesis. However, prior to this work, there has been very limited and conflicting literature available about the adsorption of of pyridine derivatives analogous to DMAP. Among the pyridine derivatives that were studied, some reports indicate that, other than DMAP, only 4‐methoxy pyridine (MOP) can stabilize gold nanoparticles. However, very little is known about the possible differences in the adsorption energy and general behaviour of MOP compared to DMAP. Resolving this knowledge gap is imperative to resolving the conflicting information about pyridine‐based stabilizers for metal nanoparticle applications. The adsorption behaviour of MOP on different crystallographic Au surfaces as a function of pH and surface potential has been investigated in this project. These studied were carried out using classical electrochemical methods including chronocoulometry and differential capacity, as well as modern spectroscopic techniques like Surface Enhanced Infrared Absorption Spectroscopy (SEIRAS). The thermodynamic parameters obtained from electrochemical data shows that adsorption features of MOP is similar to that of DMAP. However, there is a significant difference in the adsorption strength of MOP and DMAP at positive potentials. The SEIRAS data provides much more detailed information about the potential depended orientation of MOP on polycrystalline Au. Cumulative analysis of electrochemical and spectroscopic data provides strong evidence that MOP can stabilize Au(111) facets over wide pH ranges. Moreover, this work provides convincing evidence that the basic nature of substituted pyridine alters the metal to ligand adsorption strength.

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