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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.
71

Impacts of Maternal Obesity on Metabolic Profiles in Postpartum Ewes

McKnight, Jason Ray 2010 August 1900 (has links)
This study determined the effects of gestational obesity on the long-term metabolic status of the mother and if obesity management during or after pregnancy could attenuate these effects. At 120 days prior to estrus, 8 ewes received 100 percent of NRC nutrient requirements (control group) and 24 ewes had free access to feed (obesity induction). Beginning on day 42 of gestation, 8 obese ewes were restricted to 65 percent of NRC nutrient requirements. Following parturition, controls and all but one group of obese ewes were fed 100 percent of NRC nutrient requirements. At postpartum days (PPD) 1 and 150, glucose tolerance tests were administered to ewes. At both PPD1 and PPD150, obesity resulted in insulin resistance, impairment of whole-body glucose utilization, increased levels of circulating leptin, and altered profiles of amino acids in plasma; however, these effects were diminished in ewes receiving obesity management during or after gestation. Additionally at PPD150, obesity increased the circulating levels of ammonia and urea in ewes, which was prevented by realimentation to 100 percent NRC requirements. These results indicate that weight reduction in obese dams during pregnancy or after parturition can beneficially ameliorate the adverse effects of gestational obesity on the mother.
72

Evaluating the von Kármán Constant in Sediment-laden Air Flow

Li, Bailiang 2010 December 1900 (has links)
Shear velocity is a critical variable used in many hydrodynamic and aeolian applications. The Law of the Wall is commonly used to derive shear velocity as the product of the slope of a measured velocity profile and the von Kármán constant, κ = 0.4. However, a number of hydrodynamic experiments show that there is a substantial apparent decrease of κ in sediment-laden flow, which was explained by: 1) The energy loss to support the sediment particle suspension in the fluid and 2) The buoyancy effect due to stratification. The energy loss is associated with sediment concentration and grain size, and the stratification can be characterized by sedimentological flux Richardson number or gradient Richardson number. Since there is an apparent change of κ, the term “apparent von Kármán parameter”, or κa, was adopted from Wright and Parker to replace κ in sediment-laden flow. There has been no study to attempt to detect and to evaluate the variability of κa during aeolian saltation, which is the purpose of this dissertation research. Two “clear air” runs and fifteen “sediment-laden” runs were conducted at the northeast coast of Brazil. Wind profile data were collected by a stack of cup anemometers; “true” shear velocity was estimated by an ultrasonic anemometer; and sediment mass flux profile and grain size were estimated from the sand samples collected in a stack of vertical hose-style traps. With these estimates, κa, sediment concentration and sedimentlogical Richardson numbers were derived. Regression analysis indicates that there is a statistically insignificant relationship between κa and grain size, which may be caused by small range of grain size in the study site. However, there is strong statistical relationship between κa and bulk, volumetric concentration below 25 mm, S25, and between κa and sediment transport rate Q (kg/m/s) as: ka = -2088.4S25 0.3964 and ka = -3.134Q 0.4011 A strong relationship was also found between κa and sedimentological Richardson numbers in the lower saltation layer, which can be well explained by the stratification theory.
73

Personality Traits and User Behavior

King, Christopher Ronald 2011 December 1900 (has links)
Psychologists and human resources personnel have used personality profiling as a predictor of human behavior in various environments for many decades. Knowing the personality traits of a particular individual allows management to tailor an environment ideally suited for an individual, attempting to maximize a person's productivity and job satisfaction. Measurements of personality are classically achieved through a self-reporting survey. This method has a potential inaccuracy due to its lack of objectivity and a bias due to cultural influences. This research explores the relationships between specific computer user behavior patterns and personality profiles. The results may provide a partial map between personality profile traits and computer user behavior. In an attempt to discover such correlations, forty-five fraternity and sorority students from Texas A&M University were selected to participate in a personality survey and three computer based tests. One test measured the subject's perceptive abilities, another measured their decision-making requirements, and a third measured their methods employed in organizing a task. The results show conclusively that some personality profile traits do influence how people visually interpret information presented on a computer screen. Individuals who exhibit high conscientiousness or agreeableness scores on a personality assessment survey take less time to find an icon among a collection during an icon search test. However, the results also show a significantly large variability in individuals, indicating that many other factors may influence attempts to measure an individual's personality traits. This indicates that the tests presented in this study, even though they show that behavior is related to personality traits, cannot be used as diagnostic tools. Further research will be required to obtain that goal.
74

A Design on the Bevel Gear with Circular-Tooth Profiles for Manufacturing

Hsieh, Ming-Lung 08 July 2003 (has links)
The bevel gears have been widely used for the intersected-axial transmission system for a long time. But mostly them are limited in the category of involute tooth profiles. It is believed that bevel gears with circular-arc tooth profile, similar to the Wildhaber-Novikov circular-arc helical gears, will improve the load capacity of the gear set. The bevel gears with circular-arc tooth profiles was firstly proposed by Kuo and Tsai in 2001. Although these new type of bevel gears can increase the load capacity of transmission, the expensive manufacturing process is still the problem. In this paper, the design parameters of bevel gear with circular-arc profiles developed by Kuo and Tsai are modified. Bevel gear set with spiral point contact path is developed. This improvement makes it possible to manufacturing the newly developed bevel gears in just a simple milling or/and grinding process with circular cutting edges. The manufacturing process is then cost down quit a lot. A method for checking the gear interference is also proposed. Finally, the 3D solid models of the bevel gear with circular-arc tooth profiles as well as the grinding wheel are constructed by using the computer software ¡§Pro/E¡¨. It is believed that the mathematical models and the design method developed in the thesis will provide a useful foundation for the further studies.
75

'It means a lot to me' : an investigation into the place of sport through women's lives and leisure

Talbot, Margaret January 1991 (has links)
Using feminist perspectives, the treatment of women's participation in leisure sport within leisure studies and the sociology of sport, is explored. The review traces the progress made, in moving enquiry away from questions of distribution, towards questions of relations between women and men and how these are reproduced and enacted in leisure and sports experiences. Epistemological and methodological issues f acing feminist researchers in leisure studies and the sociology of sport are outlined. The research explored the dynamics between women's uses and control of time, their framing and definition of leisure sport in their own lives, past and present. A cumulative approach, using several research methods, was developed. Forty women, twenty badminton and twenty hockey players, were research partners. Interactions with each included: use of interview pro formas for personal profiles, participation parameters and weekly time profiles; personal life histories; and questions designed to link, check and provide perspective. The methods were effective for exploring changes in meanings of leisure and sport activities over time. The main findings included the centrality of "others" in women's uses of time and sport experiences, and recurrent themes of autonomy and control, recovery, personal fulfilmont, tensions between commitments and constraints, and sport as "cultural capital". The findings are related to issues of public policy and provision in leisure and sport.
76

Development of a new low resolution spectrograph for probing Lyman-alpha emitters in the HETDEX survey

Chonis, Taylor Steven 21 September 2011 (has links)
The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) will map the power spectrum of 0.8 million blindly discovered Lyman-alpha Emitting Galaxies (LAE) using a revolutionary new array of massively replicated, fiber-fed spectrographs dubbed the Visible Integral-Field Replicable Unit Spectrograph (VIRUS). In the era of the Hobby-Eberly Telescope wide-field upgrade, the current Low Resolution Spectrograph (LRS) must be replaced with a fiber instrument. In this thesis, I discuss the development of the second generation LRS (LRS2), which is an R>1200 multi-channel instrument based on the VIRUS design and fed by a 287 fiber, 7” x 12” microlens coupled integral field unit. I focus on the blue optimized version of the instrument (3720<[lamda] (Angstroms)<7000), specifically on the opto-mechanical design of the VPH grisms. With the purpose of making the instrument ideal for the follow-up of LAE in the HETDEX survey, I discuss the science drivers for selecting the spectral resolution of the instrument. To test the utility of such an instrument, I present R~2400 spectra of two LAE that were originally discovered in the HETDEX Pilot Survey (Adams et al. 2011). These data were taken with the VIRUS prototype spectrograph in a high-resolution mode at the McDonald Observatory Harlan J. Smith 2.7 m telescope. The Lyman-alpha line profiles are constrained by near-infrared observations of rest-frame optical emission lines from Finkelstein et al. (2011), which set the systemic redshift of the galaxies. I discuss the velocity offsets of the Lyman-alpha line from the systemic line center and the implications for the HETDEX survey. I compare the line profiles to theory, specifically to those describing dust attenuation, outflows or inflows of neutral gas on the galactic scale, and attenuation in the intergalactic medium. This study provides an example of how LRS2 can be used to probe Lyman-alpha emission in 2<z<3 star-forming galaxies. / text
77

VPU Psichologijos specialybės studentų intelektinių gebėjimų struktūros profilio ypatumai / The peculiarities of the intelect profiles of VPU psychology students

Bajoriūnienė, Karolina 24 September 2008 (has links)
Šio tyrimo metu buvo atskleisti VPU psichologijos studentų intelekto struktūros profilio ypatumai. Intelektas yra svarbus veiksnys, pasirenkant tolimesnę mokymosi kryptį. Jis kaip kompasas nurodo, kurioje aplinkoje asmenybė galės prisitaikyti ir atsiskleisti. Su intelektu yra susiję specialieji gabumai, nuo jo priklauso sprendimo priėmimo lankstumas, tikslus rinkimosi situacijos įvertinimas ir ateities numatymas. / The aim of this study was to reveal the intellectual capabilities of VPU psychology I, II, III, IV course students. The Amthauer’s IST-70 method was used to research the intellect of students.
78

Physicochemical Changes of Coffee Beans During Roasting

Wang, Niya 20 April 2012 (has links)
In this research, physicochemical changes that took place during roast processing of coffee beans using fluidized air roaster were studied. The results showed that high-temperature-short-time resulted in higher moisture content, higher pH value, higher titratable acidity, higher porous structure in the bean cell tissues, and also produced more aldehydes, ketones, aliphatic acids, aromatic acids, and caffeine than those processed at low-temperature-long-time process. Fourier transform infrared (FTIR) spectroscopy and chemometric analysis showed that clusters for principal components score plots of ground coffee, extracted by a mixture of equal volume of ethyl acetate and water, were well separated. The research indicated that variations in IR-active components in the coffee extracts due to different stages of roast, roasting profiles, and geographical origins can be evaluated by the FTIR technique. / Natural Sciences and Engineering Research Council of Canada (NESRC) and Mother Parkers Tea & Coffee Inc.
79

Exploring cognitive profiles of children with learning difficulties

Tonn, Ryan Unknown Date
No description available.
80

Diacylglycerol: mechanism and efficacy as a functional oil

Yuan, Quangeng 12 September 2008 (has links)
BACKGROUND: Diaclyglycerol (DAG) oil has the potential as an effective weight control agent as well as an agent to modify overweight related complications. OBJECTIVE: We aim to examine the efficacy of DAG oil (Enova oilTM) on regulating energy expenditure (EE), fat oxidation, body composition, lipid profiles and hepatic lipogenesis in comparison with conventional oils. DESIGN: Twenty-six overweight hypertriglyceridemic women consumed DAG or control oil for 28 days separated by a 4-week washout period using a randomized crossover design. Forty grams of either DAG or control oil were consumed daily by each study subject. RESULTS: DAG oil consumption for a period of 4-week does not alter total EE, fat oxidation, lean mass, fasting lipid profile or fatty acids synthesis rate, but effectively reduces (p<0.05) body weight and adiposity. CONCLUSION: DAG oil maybe an useful agent in the battle against obesity. However, its body weight/composition control effects are not from increasing of lean mass, or postprandial EE and fat oxidation. The consumption of DAG oil for a period of 4-week does not necessarily modify fasting lipid profiles or hepatic lipogenesis to reduce risk of coronary heart diseases in overweight hypertriglyceridemic subjects.

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