508 research outputs found
Impaction of the Small Colon in a Shetland Pony
On Oct. 20, 1954, a 6-month-old Shetland pony was admitted to Stange Memorial Clinic. The history revealed that the animal had been treated for impaction on October 18. Oil and enemas were given by the local practicing veterinarian to no avail. Therefore, a laparotomy was decided upon
Magic and Machine: Using the Repre Method of Theatrical Devising to Explore the Themes of Science, Spiritualism, and the Human Brain
This thesis explores the application of The Repre Method of theatrical devising (also know as the RSVP cycles) to the ensemble-devised creation, Brain Storm. The narrative of the play centers on 3 characters; one woman dealing with a brain injury and its emotional and cognitive fall-out, another who believes she can communicate with the deceased across barriers of time and space, and the famous Canadian neuro-surgeon Wilder Penfield, who used electrical stimulation to provoke sensory hallucinations in his patients. The Repre Method, which uses objects and stories as resources for the actors to engage with, is explored as a means to find compelling narrative and emotional connection within the devising process and workshop production
Effects of reduced pH on health biomarkers of the seagrass Cymodocea nodosa
Ocean acidification is a growing problem that may affect many marine organisms in the future. Within 100 years the pH of the ocean is predicted to decrease to 7.8, from the current ocean pH of around 8.1. Using phenolic acid levels as a stress indicator as well as respiration and chlorophyll content as a measure of health, the effect of lowering pH was tested on the seagrass, Cymodocea nodosa, in a controlled environment. Plant samples, water, and soil were taken from the Bay of Cádiz, Spain, and placed in aquaria in a temperature-controlled room. One control group was left untreated with a pH of approximately 8.1, while experimental groups maintained pH levels of 7.8 and 7.5. Using High Performance Liquid Chromatography (HPLC), concentration of the phenol rosmarinic acid was quantified in the plants. Average concentration for the control group was 1.7 μg g-1, while it was 2.9 μg g-1 for pH group 7.8, and 10.1g g-1 for pH group 7.5. To evaluate the overall health of C. nodosa within the three groups, chlorophyll concentration and photosynthesis/respiration rates were determined. A one-tailed ANOVA test was conducted using the chlorophyll concentrations of the three groups. With an F-value of 1.360 and a p-value of 0.287, the differences between the groups were not statistically significant. Although the raw data shows a slight decrease in chlorophyll content between the control group and the pH group 7.5, these discrepancies might have been larger or smaller due to sampling or experimental error. Additionally, the average values with their respective standard deviations were calculated for the respiration rates and oxygen production of each group. A one-tailed ANOVA was also used to determine the relationship between rosmarinic acid content and pH levels between the groups, with an F-value of 5.1423 and a p-value of 0.050
Intercultural Competence Development through the Global Awareness Program at the University of Kansas
The purpose of this study is to understand whether undergraduate students develop intercultural competence through domestic, co-curricular international and intercultural programming. This evaluative case study focuses on students who did not study abroad and earned the Global Awareness Program (GAP) certificate at the University of Kansas (KU). Byram's 1997 definition of intercultural competence provided the conceptual framework for this study. Informed by this definition, my working definition of intercultural competence includes the following components: knowledge of one's own and other cultures, the ability to understand differences between and among cultures, skills to interact effectively with people from different cultural backgrounds, and attitudes of open-mindedness and empathy toward people from different countries and cultures. Using a rubric devised from Byram's definition of intercultural competence and open-coding of the essays, several themes emerged from the data: types activities (interactive or passive), increased knowledge, understanding of diversity within cultures, feelings of empathy, feelings of gratitude, expression of open-mindedness, future goals, imperative of international and intercultural studies, cultural comparison, and regions of the world. Although many of the themes reflected components of intercultural competence, the analysis of the students' GAP portfolios revealed that only a very small number of students showed strong evidence of intercultural competence development. It seems to suggest that administrators in the KU Office of International Programs should consider limiting passive activities which do not elicit reflection, changing essay requirements to invite more reflection, and explore why so few students who do not study abroad take advantage of the GAP
Modeling of solar thermal selective surfaces and thermoelectric generators
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 101-107).A thermoelectric generator is a solid-state device that converts a heat flux into electrical power via the Seebeck effect. When a thermoelectric generator is inserted between a solar-absorbing surface and a heat sink, a solar thermoelectric generator is created which converts sunlight into electrical power. This thesis describes the design and optimization of solar thermoelectric generators, with a focus on systems with high optical concentration which utilize multiple material systems to maximize efficiency over a large temperature difference. Both single-stage and cascaded (multi-stage) generators are considered, over an optical concentration range of 0.1 to 1000X. It is shown that for high-concentration Bi₂Te₃/skutterudite solar thermoelectric generators, conversion efficiencies of 13% are possible with current thermoelectric materials and selective surfaces. Better selective surfaces are needed to improve the efficiency of solar thermoelectric generators. In this thesis, ideal selective surfaces for solar thermoelectric generators are characterized. Non-ideal selective surfaces are also characterized, with emphasis on how the non-idealities affect the solar thernoelectric gencrator performance. Finally. the efficiency limit for solar thermoclectric generators with non-directional absorbers is presented.by Kenneth McEnaney.S.M
Modeling and optimization of solar thermoelectric generators for terrestrial applications
In this paper we introduce a model and an optimization methodology for terrestrial solar thermoelectric generators (STEGs). We describe, discuss, and justify the necessary constraints on the STEG geometry that make the STEG optimization independent of individual dimensions. A simplified model shows that the thermoelectric elements in STEGs can be scaled in size without affecting the overall performance of the device, even when the properties of the thermoelectric material and the solar absorber are temperature-dependent. Consequently, the amount of thermoelectric material can be minimized to be only a negligible fraction of the total system cost. As an example, a Bi[subscript 2]Te[subscript 3]-based STEG is optimized for rooftop power generation. Peak efficiency is predicted to be 5% at the standard spectrum AM1.5G, with the thermoelectric material cost below 0.05 $/W[subscript p]. Integrating STEGs into solar hot water systems for cogeneration adds electricity at minimal extra cost. In such cogeneration systems the electric current can be adjusted throughout the day to favor either electricity or hot water production
A review of cermet-based spectrally selective solar absorbers
Spectrally selective solar absorbers harvest solar energy in the form of heat. Solar absorbers using cermet-based coatings demonstrate a high absorptance of the solar spectrum and a low emittance in the infrared (IR) regime. Extensive work has been done to optimize cermet-based solar absorbers to achieve high performance by exploring different cermet (ceramic–metal composite) materials and film configurations through different preparation techniques such as electrodeposition, sputtering, pulsed laser deposition, and solution-based methods. In this article, we review the progress of cermet-based spectrally selective absorbers with high solar absorptance and low thermal emittance, such as Cr[subscript 2]O[subscript 3], Al[subscript 2]O[subscript 3], AlN, SiO[subscript 2], and ZrO[subscript 2] based cermets as absorption layers. We also present an outlook for cermet-based spectrally selective absorbers with high thermal stability and high conversion efficiency from sunlight to heat.United States. Dept. of Energy (SunShot CSP Grant Award DE-EE0005806
Optical cavity for improved performance of solar receivers in solar-thermal systems
A principal loss mechanism for solar receivers in solar-thermal systems is radiation from the absorbing surface. This loss can be reduced by using the concept of directional selectivity in which radiation is suppressed at angles larger than the incident angle of the sunlight striking the absorber. Directional selectivity can achieve efficiencies similar to high solar concentration, without the drawbacks associated with large heat fluxes. A specularly reflective hemispherical cavity placed over the absorber can reflect emitted radiation back to the absorber, effectively suppressing emission losses. An aperture in the cavity will still allow sunlight to reach the absorber surface when used with point focus concentrating systems. In this paper the reduction in radiative losses through the use of a hemispherical cavity is predicted using ray tracing simulations, and the effects of cavity size and absorber alignment are investigated. Simulated results are validated with proof of concept experiments that show reductions in radiative losses of more than 75% from a near blackbody absorber surface. The demonstrated cavity system is shown to be capable of achieving receiver efficiencies comparable to idealized spectrally selective absorbers across a wide range of operating temperatures.United States. Dept. of Energy (“Concentrated Solar Thermoelectric Power”, a DOE SunShot CSP Grant, under award number DE-EE0005806
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