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- Title
- The mass fire potential of urban structure and form
- Creator
- Schar, Stephen Warren
- Date
- 1969
- Collection
- Electronic Theses & Dissertations
- Title
- The role of fetuin-A on adipose tissue lipid mobilization in dairy cows
- Creator
- Strieder-Barboza, Clarissa
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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Adipose tissue (AT) is a major modulator of metabolic functions by regulating energy storage and acting as an endocrine organ. In periparturient dairy cows, increased AT mobilization of free fatty acids (FFA) is one a major adaptive mechanism to cope with higher energy demand for rapid fetal growth and the onset of lactation. As lactation progresses, lipolysis rates decrease, and lipogenesis replenishes triacylglycerol (TAG) stores in adipocytes. However, dysregulated metabolic responses,...
Show moreAdipose tissue (AT) is a major modulator of metabolic functions by regulating energy storage and acting as an endocrine organ. In periparturient dairy cows, increased AT mobilization of free fatty acids (FFA) is one a major adaptive mechanism to cope with higher energy demand for rapid fetal growth and the onset of lactation. As lactation progresses, lipolysis rates decrease, and lipogenesis replenishes triacylglycerol (TAG) stores in adipocytes. However, dysregulated metabolic responses, characterized by altered AT sensitivity to hormonal and endocrine changes around parturition, lead to a massive release of FFA into circulation and an increased susceptibility of cows to disease. These maladaptive responses are underlined by an altered secretory pattern of adipokines and a marked unbalance in lipolysis and lipogenesis rates, favoring TAG breakdown in adipocytes. Thus, identifying adipokines that modulate AT function in periparturient dairy cows can facilitate the development of novel management, nutritional, or pharmaceutical interventions to reduce disease incidence. Fetuin-A (FetA; alpha-2-Heremans-Schmid glycoprotein, AHSG) is an adipokine that functions as a carrier of FFA in plasma and is associated with insulin-mediated inhibition of lipolysis and stimulation of lipogenesis in humans. FetA increases the incorporation of fatty acids (FA) into intracellular lipids and enhances cellular TAG in human cells. However, the mechanisms by which FetA induces TAG synthesis are not defined. FetA has also anti-inflammatory properties by inhibiting the production of pro-inflammatory cytokines and acting as a negative acute-phase protein (APP) in acute inflammation. These findings suggest that FetA may also be involved in lipid mobilization and inflammation in AT of dairy cows. In our first in vivo study with periparturient dairy cows, we observed that serum and AT FetA expression decreased at the onset of lactation when lipogenesis was downregulated and plasma FFA was increased. FetA expression dynamics in AT were analogous to the patterns of lipogenic markers suggesting its link with lipid mobilization in AT of dairy cows. We also demonstrated that FetA is negative-APP locally in AT of dairy cows. These results suggest that FetA could support physiological adaptations to NEB in AT of periparturient dairy cows. To explore the potential roles of FetA on AT lipid mobilization of dairy cows, we developed an in vitro model for culturing bovine adipocytes that closely mimics the in vivo AT environment. For the first time, we reported an abundant expression and secretion of FetA by primary bovine adipocytes, thus suggesting a potential autocrine effect of FetA in AT of dairy cows. We observed that FetA attenuates lipolytic responses and enhances both, FA uptake and TAG accumulation in bovine adipocytes. Our results reveal that the upregulation of the expression and activity of 1-acylglycerol-3-phosphate acyltransferase (AGAPT2), a rate limiting lipogenic enzyme for TAG synthesis, may be a potential mechanism by which FetA enhances lipogenic function of bovine adipocytes. Overall, our results indicate that FetA is a lipogenic adipokine with anti-inflammatory function in the AT of dairy cows. Our findings provide evidence that FetA could buffer increased plasma FFA during negative energy balance by stimulating AGAPT2 activity and the use of excess FFA for TAG synthesis in AT of dairy cows. The genetic selection of cows by variations of the FetA coding gene associated with its anti-lipolytic and pro-lipogenic functions (already known in humans), the identification of dietary supplements (i.e. FA) that enhance FetA function, as well as the parenteral use of FetA to stimulate AGAPT2 activity, could serve as potential strategies to be tested and implemented in dairy cows.
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- Title
- Do changes in maize prices and input prices affect smallholder farmers' soil fertility management decisions? : panel survey evidence from Kenya
- Creator
- Olson, David William
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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Soil degradation, low cereal yields, and poor yield response to inorganic fertilizer are serious problems in many parts of sub-Saharan Africa (SSA), including Kenya. Soil fertility management (SFM) practices such as maize-legume intercropping and organic fertilizer use, particularly when used jointly with inorganic fertilizer, have the potential to increase yields and yield response to inorganic fertilizer and improve soil health. However, relatively little is known about the drivers of...
Show moreSoil degradation, low cereal yields, and poor yield response to inorganic fertilizer are serious problems in many parts of sub-Saharan Africa (SSA), including Kenya. Soil fertility management (SFM) practices such as maize-legume intercropping and organic fertilizer use, particularly when used jointly with inorganic fertilizer, have the potential to increase yields and yield response to inorganic fertilizer and improve soil health. However, relatively little is known about the drivers of adoption of such SFM practices, including their joint use. Moreover, it is often suggested that African farmers will respond to an increase in the maize price they expect to receive at the next harvest by increasing investment in their soils or that they might alter their use of SFM practices in response to changes in input prices. Yet previous studies largely ignore the role of such prices. Using nationwide household panel survey data from Kenya, we first predict the maize price a household can expect to receive at the upcoming harvest based on observables at the time they make SFM decisions; we then estimate the effects of changes in this predicted maize price and input prices on household adoption decisions for individual SFM practices and combinations thereof. Likely due to multiple market failures, we find that Kenyan smallholders’ SFM adoption decisions are largely insensitive to changes in prices; however, there is some evidence that they are more likely to use organic fertilizer and use less inorganic fertilizer per acre when inorganic fertilizer prices rise.
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- Title
- A multidimensional treatment integrity assessment of parent coaching in a telehealth parent training program for autism spectrum disorder
- Creator
- Tran, Shannon Quyen
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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An important principle of evidenced-based practice (EBP) is using interventions with strong empirical support for their effectiveness, commonly known as evidence-based interventions (EBIs). Evidence of an intervention’s effectiveness is strongest when supported by treatment integrity data. Treatment integrity refers to the degree to which an intervention is implemented as intended by the original design. The assessment’s purpose is to provide researchers and practitioners with data about the...
Show moreAn important principle of evidenced-based practice (EBP) is using interventions with strong empirical support for their effectiveness, commonly known as evidence-based interventions (EBIs). Evidence of an intervention’s effectiveness is strongest when supported by treatment integrity data. Treatment integrity refers to the degree to which an intervention is implemented as intended by the original design. The assessment’s purpose is to provide researchers and practitioners with data about the implementation process to enable valid conclusions to be drawn about an intervention’s effectiveness.The present study focused on the treatment integrity assessment of Project ImPACT (Improving Parents as Communication Teachers; Ingersoll & Dvortcsak, 2010), a parent training program that aims to improve parents’ competence in teaching social communication skills to children diagnosed with autism spectrum disorder (ASD). The parent coaching portion of the training program was the focus of this study. Treatment integrity assessment occurred at two stages: The coaching delivery and the treatment delivery.This study used videos of coaching sessions from two randomized controlled trial (RCT) studies that examined the effectiveness of delivering Project ImPACT via telehealth with and without parent coaching. Dane and Schneider’s (1998) treatment integrity conceptual framework was used to guide the assessment. For the coaching delivery, the assessment focused on the therapists’ adherence to the coaching procedure, provision of feedback, and quality of coaching delivery, and the parents’ responsiveness during the coaching session. For the treatment delivery, the assessment focused on the parents’ adherence to the intervention strategies and quality of the treatment delivery. Descriptive statistics provided a general overview of the therapists’ coaching performance and the parents’ teaching performance. Multilevel regression analysis determined which components of the coaching delivery best predicted how parents used the intervention techniques and structured the play session for their child during the coaching sessions.Overall, the therapists consistently completed the essential steps of the coaching process. They frequently provided comprehensive feedback, attention, and reassurance. They did not provide as many opportunities for the parents to engage in collaborative problem-solving or to reflect on their implementation progress. In turn, the parents fully participated in the coaching session and demonstrated sufficient capacity to implement the intervention techniques and structure a meaningful play session for their child.Results from a multilevel regression analysis indicated that none of the treatment integrity components of the coaching delivery significantly predicted the parents’ treatment adherence. The quality of coaching delivery did, however, significantly predict the parents’ structure of the play segment, albeit in a negative direction. The study’s results, along with its limitations, provided a platform for continuing the conversation about treatment integrity assessment in intervention studies. In particular, the study concluded with new questions about the conceptualization and operationalization of different parent coaching aspects for parent-implemented interventions. Seeking to understand the concept and improve the measurement of these parent coaching aspects can lead to a more accurate identification of the active ingredients of parent coaching in ASD parent-implemented interventions.
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- Title
- Effect of centrifugation on root initiation in Vaccinium corymbosun, L. and Salix alba, L
- Creator
- Siripong, Dusit
- Date
- 1966
- Collection
- Electronic Theses & Dissertations
- Title
- A study of empathic ability and of the validity of some indices of job satisfaction
- Creator
- Schell, William Adolph
- Date
- 1954
- Collection
- Electronic Theses & Dissertations
- Title
- Characteristics observed of infant's swimming ability : a four month study conducted in order to establish teaching methods for this level
- Creator
- Scheunemann, Virginia Lee
- Date
- 1961
- Collection
- Electronic Theses & Dissertations
- Title
- Labor's image of its place in the community power structure : an exploratory study
- Creator
- Sauer, Warren Louis
- Date
- 1958
- Collection
- Electronic Theses & Dissertations
- Title
- Fundamental studies and engineering modeling of hydrogen bonding
- Creator
- Bala Ahmed, Aseel Mohamed Ahmed
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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This project aims to enhance the engineering modeling of hydrogen bonding, or association, by blending ab initio quantum calculations, fundamental molecular level findings from experimental techniques, and thermodynamic models. Because of the ubiquity of hydrogen bonding, applications for an improved association model are extensive, ranging from drug design to plastics manufacturing. Therefore, a substantial amount of work has been aimed at improving traditional thermodynamic tools, which...
Show moreThis project aims to enhance the engineering modeling of hydrogen bonding, or association, by blending ab initio quantum calculations, fundamental molecular level findings from experimental techniques, and thermodynamic models. Because of the ubiquity of hydrogen bonding, applications for an improved association model are extensive, ranging from drug design to plastics manufacturing. Therefore, a substantial amount of work has been aimed at improving traditional thermodynamic tools, which often fail to capture the behavior of associating systems accurately. To guide models, spectroscopic techniques have been leveraged to gain insight into the interactions between molecules in the liquid phase, but interpretation is difficult. Moreover, with the advancement of computational chemistry technology, molecular dynamics (MD) and quantum mechanical (QM) calculations have also been utilized to understand the characteristics of hydrogen bonded clusters. However, few studies have combined all 3 techniques (the thermodynamic model, spectroscopy and ab initio calculations) in a rigorous way. To this end, an activity coefficient model for association is developed using Wertheim’s perturbation theory and its capabilities and limitations are explored with parameters from literature. Furthermore, a sequential MD and QM protocol is designed which facilitates the interpretation of the hydroxyl vibration in infrared spectroscopy and a method is developed to quantify the entire band. Finally, the methods are used to calculate the value of the association constant for an alcohol + alkane system.
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- Title
- Vicarious interaction with politicians by identifying with surrogates on social media : a social identification mechanism based on multiple salient social categories
- Creator
- Dai, Yue (College teacher)
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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New media platforms display politicians’ interactions with people from a variety of social categories. Previous research shows that observers could vicariously experience parasocial intimacy toward a public figure by identifying with a surrogate—an individual who directly interacts with the public figure and who is considered an ingroup member by the observer based on a salient social category (Dai & Walther, 2018). Developments in the social identity literature call for further examination...
Show moreNew media platforms display politicians’ interactions with people from a variety of social categories. Previous research shows that observers could vicariously experience parasocial intimacy toward a public figure by identifying with a surrogate—an individual who directly interacts with the public figure and who is considered an ingroup member by the observer based on a salient social category (Dai & Walther, 2018). Developments in the social identity literature call for further examination of this surrogacy effect in contexts where multiple social categories are activated as bases upon which observers identify with surrogates. Through two experiments involving a total sample of 1,068 participants, this research demonstrates that when a surrogate’s identity is presented as different combinations of political affiliation (democratic or republican) and social status (ordinary voter or politician), the more categories observers share in common with the surrogate, the more they identify with the surrogate, and thereby experiences greater parasocial intimacy toward a politician who is seen replying to the surrogate on Twitter. These findings extend previous findings on a social identification-based mechanism of the surrogacy effect and inform online impression management practices of politician.
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- Title
- Poly(ethylene glycol) tailored polymers : nanomicelles with tunable lower critical solution temperature behavior
- Creator
- Lien, Yu-Ling
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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Propargyl and 1,1-dimethyl propargyl substituted poly(ethyleneoxides) (propargyl substituted = poly(PGE), 1,1ʹ-dimethyl propargyl substituted = poly(MGE)) have been prepared by ring-opening polymerization of epoxides, which were synthesized from epichlorohydrin and propargyl or 1,1-dimethyl propargyl alcohol via Williamson ether synthesis. The resulting polymers were modified by Cu-catalyzed azide alkyne cycloaddition (CuAAC) of the polymer propargyl groups and organic azides. When these...
Show morePropargyl and 1,1-dimethyl propargyl substituted poly(ethyleneoxides) (propargyl substituted = poly(PGE), 1,1ʹ-dimethyl propargyl substituted = poly(MGE)) have been prepared by ring-opening polymerization of epoxides, which were synthesized from epichlorohydrin and propargyl or 1,1-dimethyl propargyl alcohol via Williamson ether synthesis. The resulting polymers were modified by Cu-catalyzed azide alkyne cycloaddition (CuAAC) of the polymer propargyl groups and organic azides. When these reactions were carried out with mixtures of azides, the ratios of azides incorporated in the polymer side chains were equal to the molar ratios of the organic azides reactants (± 2%). Mixtures of hydrophobic (decyl azide) and hydrophilic (mDEG azide) azides result in amphiphilic polymers that exhibited a lower critical solution temperature (LCST) behavior. The polymer LCSTs scaled from 48 to 97 ± 2 °C (poly(PGE) derived amphiphiles) and 4 to 46 ± 1 °C (poly(MGE) derived amphiphiles) in a roughly linear fashion with the mole fraction of hydrophilic side chains in the polymer. When charged azides, COOH azide and aminium azide, were used, the physical property as well as the LCST behavior oh the polymers were changed. The LCSTs of polymers incorporating charged azides were increased and the LCSTs were decreased by adding salts in the solutions. The hydrodynamic radii (RH) obtained from DLS measurements indicate that polymers form unimolecular micelles in water (Mn = 52,000 g/mol, PDI = 1.19, RH = 6 ± 2 nm), and TEM data showed monodisperse domains (20 ± 4 nm, for Mn = 52,000) when water was evaporated at room temperature from solutions cast on TEM grids. This length scale is consistent with domains that consist of single polymer chains. When the TEM grid was heated during evaporation, the domain size increased to 74 ± 45 nm. In solution, the unimolecular micelles can solubilize hydrophobic small molecules, such as trans-azobenzene (trans-PhN=NPh) in water. DLS data suggested that polymer encapsulating trans-PhN=NPh (trans-PhN=NPh@poly(PGE) or poly(MGE)) derived amphiphiles) showed signs of aggregation in one case (RH = 12 ± 8 nm) and no signs of aggregation in another case (RH = 5 ± 2 nm). When the resulting solutions were raised above the polymer LCST the polymer and small molecule precipitated. When the mixture was cooled below the LCST, the polymer and hydrophobic small molecule re-dissolved. The unimolecular micelles were used to encapsulate a hydrophilic macromolecule, Subtilisin Carlsberg (SC), in aqueous solution and organic media. Poly(PGE) or poly(MGE) derived amphiphiles with COOH pendant group slowed down SC aggregation in aqueous environment. Also, the activity of SC@poly(MGE) derived amphiphiles with COOH pendant group was assayed and the half-life of SC was increased to 10 h from 2 h at 50 °C. Initial studies of SC@poly(PGE) or poly(MGE) derived amphiphiles in organic media showed enzymatic activity in toluene after 16 h at 37 °C.
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- Title
- Aerial photography
- Creator
- Schaeffer, Robert Owen
- Date
- 1938
- Collection
- Electronic Theses & Dissertations
- Title
- The design, development, fabrication and testing of a 100 watt skutterudite thermoelectric generator
- Creator
- Lyle, Matthew
- Date
- 2011
- Collection
- Electronic Theses & Dissertations
- Description
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Thermoelectric technology is a method of renewable, alternative energy that utilizes the Seebeck effect to convert some of the thermal energy in a temperature gradient to electricity. The optimal temperature range for skutterudite thermoelectric devices is around 650°C, making them ideal for high temperature applications. At this temperature range, the skutterudite thermoelectrics have a device-level conversion efficiency of about 9%. As these devices are still in the development stage,...
Show moreThermoelectric technology is a method of renewable, alternative energy that utilizes the Seebeck effect to convert some of the thermal energy in a temperature gradient to electricity. The optimal temperature range for skutterudite thermoelectric devices is around 650°C, making them ideal for high temperature applications. At this temperature range, the skutterudite thermoelectrics have a device-level conversion efficiency of about 9%. As these devices are still in the development stage, testing that simulates real-world conditions is necessary to assess the feasibility of implementing skutterudite thermoelectric technology with current processes. A standardized procedure to test the skutterudite thermoelectric devices has been established to reduce variability in device fabrication and generator assembly. This procedure includes a measurement and tracking system to aid in establishing relationships between component properties and thermoelectric performance. In addition, a technology has been developed to electrically bypass any failed devices to preserve overall power generation.Results indicate that additional efforts are needed to address the high level of thermal stresses the devices experience during operation. Several methods to reduce thermal stresses and investigate potential stressors are proposed. In addition, the successful performance of the electrical bypass technology suggests that it is indeed a viable method of bypassing individual devices for experimental tests. Additional testing and improvements can be made as necessary to implement this technology in the envisioned 1 kW skutterudite thermoelectric generator.
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- Title
- Pacific Standard Time : modernism and the making of West Coast jazz
- Creator
- Spencer, Michael Thomas
- Date
- 2011
- Collection
- Electronic Theses & Dissertations
- Description
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An interdisciplinary study of one of the most overlooked and understudied movements in the history of jazz, this dissertation draws from the fields of New Jazz Studies, Popular Culture Studies, and Art History in order to reconstruct the cultural history of West Coast jazz. Focusing on the critical texts and institutions that allowed this movement to germinate and expand, I explore the ways in which the music was represented through various types of media: on record, on radio, on screen, in...
Show moreAn interdisciplinary study of one of the most overlooked and understudied movements in the history of jazz, this dissertation draws from the fields of New Jazz Studies, Popular Culture Studies, and Art History in order to reconstruct the cultural history of West Coast jazz. Focusing on the critical texts and institutions that allowed this movement to germinate and expand, I explore the ways in which the music was represented through various types of media: on record, on radio, on screen, in concert, and in print (i.e., record labels, radio stations, jazz periodicals, etc.). As a result, this study recontextualizes the West Coast jazz movement within the milieu of California modernism around the middle 20th century as a way to observe the broader jazz community; one which included musicians as well as photographers, painters, architects, sculptors, filmmakers, and other modernists.
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- Title
- Matter and energy transformation : an investigation into secondary school students' arguments
- Creator
- Onyancha, Kennedy M.
- Date
- 2010
- Collection
- Electronic Theses & Dissertations
- Title
- Toward the development of a chemo-enzymatic process for the production of next-generation taxol analogs
- Creator
- Ondari, Mark Evans
- Date
- 2010
- Collection
- Electronic Theses & Dissertations
- Title
- Aspects of NAD biosynthesis in castor bean endosperm
- Creator
- Mann, Dorothy Boerner
- Date
- 1973
- Collection
- Electronic Theses & Dissertations
- Title
- Nutritional value of the velvet bean for milk production
- Creator
- Maldonado, Jose Fernando
- Date
- 1938
- Collection
- Electronic Theses & Dissertations
- Title
- Two thousand years of foraging ecology in the endangered Hawaiian petrel : insights from stable isotope analysis
- Creator
- Wiley, Anne E.
- Date
- 2011
- Collection
- Electronic Theses & Dissertations
- Description
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Recent evidence indicates that over the last 150 years, humans may have impacted seabird populations through modification of their marine food resources. Unfortunately, the high mobility and large pelagic ranges of many seabirds has resulted in a dearth of information concerning even their basic feeding habits. Here, I use stable isotope analysis to investigate the modern and ancient foraging ecology of an endangered seabird, the Hawaiian petrel (
Pterodroma sandwichensis )....
Show moreRecent evidence indicates that over the last 150 years, humans may have impacted seabird populations through modification of their marine food resources. Unfortunately, the high mobility and large pelagic ranges of many seabirds has resulted in a dearth of information concerning even their basic feeding habits. Here, I use stable isotope analysis to investigate the modern and ancient foraging ecology of an endangered seabird, the Hawaiian petrel (Pterodroma sandwichensis ). Stable isotopic composition of Hawaiian petrel tissues (δ13 C and δ15 N values) reflects trophic level and foraging location and can therefore be used to describe patterns of foraging segregation or long-term temporal variation within the species. Chapter 1 investigates isotopic variation within individual flight feathers, with the goal of designing minimally-invasive and ecologically informative sampling strategies. δ13 C values increased from tip to base in all 52 feathers within the study, including 42 remiges from the Hawaiian petrel and 10 from the Newell's Shearwater (Puffinus auricularis newelli ). Such a consistent trend, observable among different species and age classes, is unlikely to result from shifts in diet or foraging location during feather synthesis. Considerable variation of δ15 N values was also present within feathers (average range of 1.3 / within Hawaiian petrel remiges). A sampling protocol is proposed that requires only 1.0 mg of feather and minimal preparation time. Because it leaves the feather nearly intact, this protocol will likely facilitate obtaining isotope values from remiges of live birds and museum specimens. Chapter 2 explores ecological variability among modern Hawaiian petrel populations. δ13 C and δ15 N values of feathers demonstrate segregation in foraging location during both the breeding and non-breeding seasons for petrels nesting on Kauai and Hawaii. Genetic analyses based on the mitochondrial Cytochrome b gene also reveal strong differentiation: coalescent-based analyses estimate < 1 migration event per 1,000 generations. Finally, feathers from multiple age groups and islands show unexpected divergences in δD that cannot be related to variation in source water. Overall, these data demonstrate foraging and genetic divergence between proximately nesting seabird populations. This divergence occurs despite high species mobility and a lack of physical barriers between nesting sites.Chapter 3 investigates Hawaiian petrel foraging habits and inter-colony segregation over the course of approximately 2,000 years. The most pervasive temporal trend is a 1.4-2.6 / decrease in average δ15 N values, which likely reflects declining trophic level over the past 300-1,000 years. Isotopic chronologies also document ca. 2,000 years of foraging segregation between Hawaiian petrel colonies, observed as a long-standing divergence in average δ15 N values. The degree of foraging segregation between petrel colonies diminishes through time and correlates well with genetic population structure. Shifting foraging habits of the Hawaiian petrel may reflect relatively widespread trophic alterations in the pelagic realm of the North Pacific. Such changes in foraging are concerning, given their implications for reproductive success and genetic diversity.
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- Title
- Studies on experimental histomoniasis in turkeys
- Creator
- Marcarian, Victoria, 1937-
- Date
- 1966
- Collection
- Electronic Theses & Dissertations