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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.
151

The Effectiveness of the Ketogenic Diet in Managing Type 2 DM and CVD

Fraysier, Donna, Pope, Victoria, Lee, Michelle L. 01 April 2018 (has links)
No description available.
152

The Association of Resilience with Cardiovascular Disease Among Members of the Cowlitz Indian Tribe

Nelson-Majewski, Lisa C. 01 December 2015 (has links) (PDF)
AN ABSTRACT OF THE DISSERTATION OF Lisa Nelson-Majewski, for the Doctor of Philosophy degree in Education, presented on October 30, 2015, at Southern Illinois University Carbondale. TITLE: THE ASSOCIATION OF RESILIENCE WITH CARDIOVASCULAR DISEASE AMONG MEMBERS OF THE COWLITZ INDIAN TRIBE MAJOR PROFESSOR: Dr. Dhitinut Ratnapradipa Cardiovascular disease is the leading cause of death in the United States, and among the American Indian population (AHA, 2012; IHS, 2013). The concept of resilience is receiving increasing attention in chronic conditions. Resilience has been shown to play a protective role in patients with chronic disease conditions including osteoarthritis (Wright, Zautra, & Going, 2008), breast and ovarian cancer (Brix et.al., 2008; Costanzo et. Al., 2009) and diabetes (DeNisco, 2010; Yi, Vataliano, Smith, Yi, & Weinger, 2008; Yi-Frazier et al., 2010). This study follows the paradigm shift from research focusing on risk factors of cardiovascular disease, to explore if resilience is significantly different among study participants of the Cowlitz Indian Tribe without a diagnosis of cardiovascular disease versus tribal participants with heart disease. The purpose of this study was to explore the relationships between resilience and cardiovascular health status, as well the relationship between resilience and the top six modifiable risk factors for cardiovascular disease, within the members of the Cowlitz Indian Tribe. Method. Following IRB approval, enrolled tribal members of the Cowlitz Indian Tribe, over the age of 18 years completed two survey tools. The tool utilized measure resilience this study is the 10-item Connor-Davidson Resilience Scale (CD-RISC). The second survey tool, including demographics and questions to assess cardiovascular risk factors, is the Behavioral Risk Factor Surveillance System (BRFSS). The cardiovascular risk factor questions include the same BFRSS questions utilized from the 2009-2010 BRFSS tribal questionnaires. Results. Resilience and six selected cardiovascular disease risk factors were surveyed from a total of 201 enrolled members of the Cowlitz Indian Tribe after informed consent obtained. Statistical analysis, with an alpha level of .05, revealed statistical difference between resilience and members with CVD versus resilience of members without CVD, (F (1,199) = 16.563, p = .000, ) (Table 5). All constructs of resilience impact overall resilience, while the second construct of resilience (trust in one’s instincts, tolerance of negative affect and strengthening effects of stress, emotional/cognitive control under pressure), had the most impact on overall resilience for those without CVD (r =0.909) (Table 6). HTN and resilience versus no HTN and resilience and resilience scores between those with normal cholesterol versus resilience scores of those with hyperlipidemia were the only two risk factors for CVD significantly impacted by resilience p = .049 and p = .020 respectively (Table 11; Table 13). While there was not a statistically significant difference (t (657) = -0.985) between Cowlitz Indian (N=201) resilience scores and the general population (N=458) (Davidson, 2003) (Table 22). The Cowlitz Indians (N=201) overall resilience score was statistically lower (t(359) = -3.12) than another federally recognized tribe (N = 160) Goins, Gregg, and Fiske (2012) (Table 21). Conclusion. Resilience is significantly different in members of the Cowlitz Indian Tribe who have not been diagnosed with CVD versus resilience scores of those self-identified as having CVD. Trust in one’s instincts, tolerance of negative affect and strengthening effects of stress, and emotional/cognitive control under pressure, was the construct of resilience that has the most impact on overall Cowlitz Indian resilience scores. Cowlitz participants with hypertension and hyperlipidemia, two of the six risk CVD factors evaluated, had statistical significance between the resilience scores versus the participants without the presence of these CVD risk factors.
153

(1,3-di-tert-butyltriazenide) Cu(I) as vapor deposition precursor

Bagherzadeh, Peggy January 2023 (has links)
In the past few decades, devices such as computers have become smaller, and their performance has improved beyond comparison. Semiconductors and interconnectors are used in almost all devices today and are made of thin films. Chemical vapor deposition (CVD) and atomic layer deposition (ALD) are common methods for depositing conformal films, where the film grows by being exposed to precursors either continuously as in CVD or by pulses as is pulsed CVD and ALD. It has been reported that Cu amidinate and guanidinate are precursors for depositing metallic Cu (Copper), but they tend to decompose. Precursors that are thermally stable and can be used to deposit a thin film of Cu are (1,3-di-tert-butyltriazenides) copper(I) (Cu-triazenides). This precursor has been synthesized and developed by the Pedersen Group in the Department of Physics, Chemistry, and Biology (IFM) at Linköpings University. This thesis investigates if Cu-triazenides are suitable as vapor deposition precursors using pulsed CVD and if Cu-triazenides are suitable as an ALD precursor with H2O as the second precursor. The main objective of this thesis is to focus on films deposited with ALD by finding the ALD window that gives a growth per cycle and making a saturation curve for each precursor. Si(100) and glass were used as the substrate, and SEM-EDX (Scanning electron microscopy- Energy- dispersive X-ray spectroscopy), XRD (X-ray diffraction), and XRR (X-ray reflectivity) analyzed the chemical, physical and, optical properties of the films. The Cu-triazenides were suitable as single-source precursors, as films were deposited with pulsed CVD on both Si(100) and glass. ALD deposited no film on Si(100) between the temperature 175–300 °C, and the analysis methods did not provide information on the thickness and composition of the films deposited on the glass.
154

Synthese und Charakterisierung neuer NHC-stabilisierter Nickelkomplexe für die Gasphasenabscheidung / Synthesis and characterization of new NHC-stabilized nickel complexes for the vapor deposition

Berthel, Johannes H. J. January 2019 (has links) (PDF)
Die vorliegende Arbeit befasst sich mit der Synthese und Charakterisierung NHC-stabilisierter Nickelkomplexe, die durch weitere Co-Liganden wie Carbonyle, Olefine, Alkine, Alkyle, Cyanide oder Allylliganden koordiniert sind. Ferner gibt diese Arbeit einen Überblick über die thermischen Eigenschaften dieser Verbindungen, um deren Potenzial für den Einsatz zur Abscheidung elementaren Nickels in CVD- bzw. ALD-Prozessen abschätzen zu können. Dabei konnten vor allem die Substanzklassen der Carbonyl- und Alkylkomplexe als geeignete Präkursoren für die Gasphasenabscheidung elementaren Nickels identifiziert werden, von denen einige ausgewählte Vertreter bereits erfolgreich in CVD-Prozessen getestet wurden. / The present work is about the synthesis and characterization of NHC-stabilized nickel complexes, which are coordinated by further co-ligands like carbonyls, olefins, alkynes, alkyls, cyanides or allylic ligands. This work presents an overview of the thermical properties of these nickel compounds, which gives an insight in their potential for using them to deposit elemental nickel in CVD and ALD processes. It was found the carbonyl and alkyl complexes were identified as useful precursors for vapor depositing elemental nickel. Some of these compounds have already been tested successfully in CVD processes.
155

Healthy and Unhealthy Diet Intake and Carotid Intima Media Thickness in Older Adults

Da Silva, Kelsey Joelle 19 October 2012 (has links) (PDF)
Background -- Cardiovascular disease (CVD) is a primary premature killer of adults and risk of CVD has been linked to modifiable risk factors including dietary intake. Many diet assessment tools are costly, time consuming, and complicated. This study investigated the relationship between diet quality and cardiovascular disease risk as indicated by carotid intima-media thickness (cIMT) using a validated, simple, self-administered rapid food screener. Methods -- Participants were 51 male and 33 female older adults with an average age of 67 years. Carotid intima-media thickness was assessed using B-mode high resolution diagnostic ultrasound. Unhealthy and healthy diet intake was assessed using a validated 22-item rapid food screener. Data on other potentially confounding variables were also collected and included blood lipid profile, BMI, and resting blood pressure. Results -- Pearson correlation analysis showed a significant relationship for the unhealthy diet pattern and cIMT for both average and maximum region cIMT (r = 0.218, p = .023; r = 0.197, p = .037 respectively). There were no significant correlations related to the healthy diet pattern. ANOVA results did indicate significant differences in cIMT means (average cIMT and maximum region cIMT) when highest intakes of fruits and vegetables were compared with lowest intakes (average cIMT, (F (1,30) 4.54, p = .041; maximum region cIMT, (F (1,30) 5.41, p = .027). Average cIMT was 0.729mm vs 0.853mm respectively for highest vs lowest fruit and vegetable intake. Maximum region cIMT was 0.864mm vs 1.023mm when comparing highest vs lowest fruit and vegetable consumers. Conclusion -- Results of this study are similar to other studies that have indicated a relationship between diet and CVD/cIMT. Dietary intakes in the present study were assessed with an easy to use, self-administered rapid food screener. This is an important aspect of the study considering previous studies have used lengthier, complicated, time intensive tools. Because the rapid food screener can be self-administered and is inexpensive it may be used as an indicator of CVD /cIMT risk by health promotion professionals and even individuals themselves.
156

Scaling Up the Synthesis of Three-Dimensional (3D) Graphene for Advanced Applications

DeArmond, Derek 23 August 2022 (has links)
No description available.
157

Synthesis and Customization of Flexible Carbon Nanotube Hybrid Sheet for Electrical and Environmental Applications

Chitranshi, Megha January 2022 (has links)
No description available.
158

Commercial chemical vapor-deposited hexagonal boron nitride: how far is it from mechanically exfoliated-like quality?

Yuan, Yue 10 November 2022 (has links)
Two-dimensional (2D) layered hexagonal boron nitride (h-BN) has become a very popular material in nanoelectronics in recent years because of its extraordinary chemical stability and thermal conductivity [1]. Recently, h-BN is also commonly used as a dielectric material [2], and research in this area is still in its early stages. The commonly used methods for fabricating h-BN include mechanical exfoliation and chemical vapor deposition (CVD). CVD is a recognized industry-compatible method for producing large-area h-BN. However, studies have shown that multilayer h-BN grown by CVD is polycrystalline and contains multiple local defects [3]. These defects and inhomogeneity cannot be avoided and lead to small amounts of atom-wide amorphous regions that have weak dielectric strength [3]. Although the general characteristics of h-BN prepared by these two fabrication methods can be learned from different works in the literature, it is difficult to study the quality of h-BN without systematically comparing the differences between the two growth methods under the same experimental conditions and with large number of samples. This also makes it difficult for researchers to choose the best-quality h-BN. In this work, the morphological characteristics and electrical properties of mechanically exfoliated h-BN and CVD-grown h-BN from different sources have been compared under different conditions. Commercially available h-BN flakes mechanically exfoliated from NIMS h-BN bulk crystal show no leakage current at electrical fields up to 25.9 MV/cm, and above this applied electrical force, the size of the conductive spots is extremely small (1.99 ± 1.81 nm2). On the contrary, “monolayer” CVD-grown h-BN samples from Graphene Supermarket were shown to be amorphous in ~20% of their area, which makes them appear discontinuous from an electrical point of view, plus they contain large thickness fluctuations up to 6 layers. Moreover, in nanoelectronic measurements collected with a conductive atomic force microscope (CAFM) working in vacuum, mechanically exfoliated h-BN showed better electrical homogeneity and presented later dielectric breakdown compared to the h-BN samples fabricated by the CVD method.
159

Thermal and Plasma Processing of Orthorhombic Gallium Oxide Films for Optoelectronic Applications

Banda, Yara S. 09 1900 (has links)
Gallium oxide (Ga2O3) has been the subject of extensive research activity due to its ultrawide bandgap and large breakdown field, which make it promising for next-generation applications in deep ultraviolet detection and power electronics. β-Ga2O3 is the most thermally stable and well-studied polymorph of Ga2O3. However, during the past decade, the metastable orthorhombic κ-Ga2O3 has emerged as an equally impressive candidate material owing to its high crystal symmetry and ferroelectric and spontaneous polarization properties. Several studies have reported the growth and characterization of κ-Ga2O3 films using different epitaxial growth methods. However, the existing literature still lacks reports on the processing of this material for future device applications. Therefore, in this thesis, we investigate the effects of high-temperature treatment and plasma exposure on the structural and optical properties of mist chemical vapor deposition (mist-CVD)-grown κ-Ga2O3 films. Using high-temperature X-ray diffraction (HT-XRD), we show that the films remain phase-pure up to an annealing temperature of 800 ˚C, after which β-phase peaks start to appear and eventually show a complete transition to β-Ga2O3 at 875 ˚C. Additionally, we show using detailed high-resolution transmission electron microscopy (HRTEM) and XRD analyses that annealing at 700 ˚C in ambient air is effective in improving the crystal quality of the κ-Ga2O3 layer by relieving in-plane strains and epitaxial stacking faults. Moreover, since dry etching is needed for the anisotropic patterning of materials for device applications, it is necessary to investigate the effects of plasma exposure on the near-surface properties of the material in order to keep its damage to a minimum. Therefore, we studied the impacts of plasma exposure during dry etching on the chemical structure, crystallinity, and optical properties of κ-Ga2O3 by using a variety of characterization methods. We observed how varying the etching parameters using BCl3/Ar can affect the near-surface properties of the material, which play a key role in modifying the performance of future devices. Specifically, we found that both RIE/ICP power and BCl3/Ar ratio can influence the surface stoichiometry and the concentration of native defect density, which affect the material’s structural and optical properties. Additionally, we reported for the first time on κ-Ga2O3 ICP-RIE process optimization using a BCl3/Ar gas mixture. By tuning the process parameters, the optimized recipe had a high etch rate of 130 nm/min, showed a surface roughness reduction of 56%, and produced vertical sidewall profiles for ridge device structures.
160

Influence of Growth Parameters on the Synthesis of MoS2 Films

Okonkwo, Victor 01 January 2022 (has links)
Information processing is crucial in modern society, placing a great emphasis on the performance of optoelectronic devices to match ever increasing processing and memory needs. Within these devices, MoS2 has demonstrated great potential as transistors due to its enhanced electrostatic control. As increased layer thickness of quality MoS2 films have been shown to boost the performance of its transistors, growth parameters for the synthesis of ideally uniform and large area multilayered films via chemical vapor deposition were investigated. By increasing the flow pressure in the system and the growth time, increasing levels of thickness and nucleation density was shown for MoS2 growth. Although the scale of the growth was non-uniform in nature, films containing large areas of thicker MoS2 was achieved. The thickness of the films was confirmed by Raman and photoluminescence measurements by confirming their values with exfoliated MoS2 measurements.

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