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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.
141

Short Term Effectiveness of High Density Large Woody Debris in Asotin Creek as a Cheap and Cheerful Restoration Restoration Action

Camp, Reid 01 December 2015 (has links)
In response to human impacts, river restoration and rehabilitation actions have become a priority in the United States. In the Pacific Northwest, most restoration actions are focused on repairing degraded freshwater habitat to increase or improve Pacific salmonid production. However, traditional river restoration actions remained largely unchanged for over 100 years despite a lack of definitive evidence that the actions were effective. More recently, there has been a surge in process-based restoration actions, which aim to reestablish the physical and biological processes that maintain fluvial and floodplain environments by targeting the root causes of degradation in a watershed. Cheap and cheerful restoration projects focus on restoration actions that are low impact and cost effective, can be implemented over large scales, and target degraded processes. However, because cheap and cheerful restoration is a relatively new method, the success of these types of projects has not been assessed. To address this issue, I studied the short-term physical effectiveness of a type of cheap and cheerful restoration that uses high density large woody debris (HDLWD) to restore instream habitat complexity in two wadeable tributaries to Asotin Creek in southeast Washington State. My specific research objectives included (1) assessing hydraulic and geomorphic responses in the stream channel imposed by restoration structures, (2) quantifying the changes to geomorphic channel unit assemblages post restoration, (3) quantifying changes in sediment storage post restoration, and (4) developing a geomorphic condition assessment of Asotin Creek using the River Styles Framework. Additionally, I developed a mobile database application (app) to facilitate data collection using a novel rapid restoration effectiveness assessment survey. Through analysis and a thorough review of the land use history in Asotin Creek, I determined that much of the watershed is in poor geomorphic condition based on the River Styles Framework for river classification. Many stream reaches have been degraded from their historic condition and often lack habitat complexity associated with suitable rearing habitat for juvenile salmonids. My results indicate that the structures are impose several immediate hydraulic responses following installation. These hydraulic responses increase hydraulic roughness, which results in predictable geomorphic responses following high flow events. Following restoration, the number and area of pools and bars significantly increased within treatment sites, while the number and area of planar units decreased. Likewise, it appears that the addition of the structures has led to a 25% increase in depositional volume at treatment sites compared to control sites. Results from the rapid assessment approach supported the more vetted approaches used to assess the efficacy of the treatment. However, the viability of the app and rapid protocol indicate that inter-observer variability may be high, and estimates of geomorphic unit area are not entirely consistent with the vetted approaches. Analysis of the rapid assessment approach revealed pertinent improvements to the app and rapid protocol that will be made in the future.
142

MICRO-CLIMATE CHARACTERIZATION OF COMFORT MATERIALS : A CLIMATE ANALYSIS OF HIGH RESILIENCE FOAM IN MICRO-CLIMATE CONDITIONS

Siddachary, Ullas January 2022 (has links)
Currently, it is widely recognised that the operational energy consumption of most building types currently outweighs their embodied energy by some margin. However, as we make dramatic increases in energy efficiency the embodied energy of the materials and components that we use will become proportionally larger and may account for a substantial proportion of the energy associated with buildings in the future. The main factor that might contribute to comfort/discomfort perception is the thermal equilibrium caused by the interaction between a person and the interaction of an object.This is easy to demonstrate as an assumption, mainly in situations where almost the whole body is in contact with the object. The main purpose of this work is to determine important parameters that differentiate different materials and develop new way of working with comfort materials (in particular, soft materials like High Resilience foam and High-Density foam) and characterize them based on their response to temperature and humidity. A literature study is performed to gain more knowledge about current state of foam technology and experimental methods are used to obtain analytical data.To characterize the materials, climate chamber is used to evaluate the materials to determine their properties. From the experiment, the key parameters were determined to be Temperature, Humidity, Vapour pressure and Heat Index. These parameters have a significant impact on the comfortability of the material and hence can be used to determine a soft material’s properties and their reaction to certain environments. The most important characteristics such as temperature, humidity, partial water vapour pressure show that HS materials which 400-450mm of PCR coating have much better sweat diffusion which can be attributed to chemical composition of the material and thermal capacity. The most difficult part micro-climate analysis is to accurately represent what is ‘comfortable’, as comfort is subjective but by using these methods of experiments and analysing methods, the characteristics of the materials can be determined, and a conclusion can be drawn. One of the most difficult things in microclimate testing or testing as such is the repetition of equal processes because it requires experience with the device and the complex process to gain comparable data. There are many variables that were not included in this study due to time constraints but can certainly add to the accuracy of the results. The study was conducted only on two materials over a certain period which can be extended for further accuracy.
143

High‐density lipoprotein mutant eye drops for the treatment of posterior eye diseases / 高比重リポタンパク変異体を利用した後眼部疾患に対する点眼治療の開発

Suda, Kenji 23 January 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20810号 / 医博第4310号 / 新制||医||1025(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 清水 章, 教授 萩原 正敏, 教授 松原 和夫 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
144

Development of Biocompatible Polymer Monoliths for the Analysis of Proteins and Peptides

Li, Yun 12 August 2009 (has links) (PDF)
Biocompatibility is an important issue for the development of chromatographic stationary phases for the analysis of biomolecules (including proteins and peptides). A biocompatible stationary phase material is a material that resists nonspecific adsorption of biomolecules and does not interact with them in a way that would alter or destroy their structures or biochemical functions. The monolithic column format is a good alternative to typical spherical particle packed columns for capillary liquid chromatography of biomacromolecules. Several novel anion-exchange polymer monoliths for the analysis of proteins were synthesized for improved biocompatibility. Two novel polymeric monoliths were prepared in a single step by a simple photoinitiated copolymerization of 2-(diethylamino)ethyl methacrylate and polyethylene glycol diacrylate (PEGDA), or copolymerization of 2-(acryloyloxy)ethyl trimethylammonium chloride (AETAC) and PEGDA, in the presence of selected porogens. The resulting monoliths contained functionalities of diethylaminoethyl (DEAE) as a weak anion exchanger and quaternary amine as a strong anion exchanger, respectively. An alternative weak anion exchange monolith with DEAE functionalities was also synthesized by chemical modification after photoinitiated copolymerization of glycidyl methacrylate (GMA) and PEGDA. The dynamic binding capacities of the three monoliths were comparable or superior to values that have been reported for various other monoliths. Chromatographic performances were also similar to those provided by a modified poly(GMA-co-ethylene glycol dimethacrylate) monolith. Separations of standard proteins were achieved under gradient elution conditions using these monolithic columns. This work represents a successful attempt to prepare functionalized monoliths via direct copolymerization of monomers with desired functionalities. Compared to earlier publications, laborious surface modifications were avoided and the PEGDA crosslinker improved the biocompatibility of the monolithic backbone. Protein separations by capillary size exclusion chromatography (SEC) require a monolith that is biocompatible, has sufficient pore volume, has the appropriate pore size distribution, and is rigid. Most polymer monoliths have not possessed a biomodal pore-size distribution, i.e., especially with one distribution in the macropore region and the other in the mesopore region. Furthermore, non-specific adsorption of proteins in these stationary phases has persisted as a major unresolved problem. To overcome these difficulties, a porous poly[polyethylene glycol methyl ether acrylate (PEGMEA)-co-PEGDA] monolith which can resist adsorption of both acidic and basic proteins when using an aqueous buffer without any organic solvent additives was developed. Based on this biocompatible monolith, surfactants were introduced as porogens with the hope of significantly increasing the mesopore volume within the polymer. Two types of surfactants were studied, including poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) or PPO-PEO-PPO and Brij. Pore size distributions were examined using a well-defined molecular weight range series of proteins and peptides by inverse size exclusion chromatography, which indicated relatively large volume percentages of mesopores and micropores. The two new monoliths demonstrated different SEC behaviors, low nonspecific adsorption of proteins, and high mechanical rigidity. High density lipoprotein (HDL) is a heterogeneous class of lipoprotein particles with subspecies that differ in apolipoprotein and lipid composition, size, density, and charge. In this work, I developed a new capillary SEC method for size separation of native HDL particles from plasma using a capillary packed with BioSep-SEC-4000 particles, Three major sizes of HDL particles were separated. Additionally, capillary SEC and capillary strong anion-exchange chromatography of non-delipidated HDL were accomplished using poly(PEGMEA-co-PEGDA) and poly(AETAC-co-PEGDA) monoliths. These new LC methods using packed and monolithic stationary phases provided rapid separation of HDLs and excellent reproducibility.
145

Relationship Between Lipid Profiles and Hypertension: A Cross-Sectional Study of 62,957 Chinese Adult Males

Chen, Siwei, Cheng, Wenke 10 October 2023 (has links)
Background Patterns of dyslipidemia and incidence of hypertension have been rarely reported in Asian populations with inconsistent findings. To accumulate further evidence in Asian populations, the study aimed to investigate the relationship between lipid profiles and hypertension in Chinese adult males. Methods We conducted a cross-sectional study based on the data from the DATADRYAD database. The overall population was divided into hypertensive and non-hypertensive groups based on baseline blood pressure levels. For continuous variables, Mann-Whitney test was performed between two groups, while Kruskal-Wallis and Dunn tests were used among multiple groups. The chi-square test was carried out for dichotomous variables. Spearman's correlation coefficient was employed to assess the association between systolic blood pressure (SBP), diastolic blood pressure (DBP) and lipid profiles, whereas the relationship between lipid profiles and the incidence of hypertension was evaluated using multivariate logistic regression. The Bayesian network (BN) model was adopted to investigate the relationship between clinical characteristics and hypertension, and the importance of related predictor to the incidence of hypertension was obtained to make conditional probability analysis. Results Finally, totally 62,957 participants were included in this study. In the lipid profiles, total cholesterol (TC), low-density cholesterol (LDL-c), and non- high-density lipoprotein cholesterol (non-HDL-c) were higher in the hypertensive population (p <0.001). In the fully multivariate model, for every 1 mg/dl increase in TC, LDL-c and non-HDL, the risk of hypertension increased by 0.2% [1.002 (1.001–1.003)], 0.1% [1.001 (1.000–1.002)], and 0.1% [1.001 (1.000–1.002)]. Meanwhile, HDL-c became positively associated with the incidence of hypertension (p for trend < 0.001) after adjusting for the body mass index (BMI), and 1 mg/dl increment in HDL-c increased the risk of hypertension by 0.2% [1.002 (1.000–1.002)] after fully adjusting for multiple variables. Furthermore, the BN showed that the importance of age, BMI, fasting plasma glucose (FPG), and TC to the effect of hypertension is 43.3, 27.2, 11.8, and 5.1%, respectively. Conclusion Elevated TC, LDL-c, and non-HDL-c were related to incidence of hypertension in Chinese adult males, whereas triglycerides (TG) was not significantly associated. The relationship between HDL-c and hypertension incidence shifted from no association to a positive correlation after adjusting for the BMI. Moreover, the BN model displayed that age, the BMI, FPG, and TC were strongly associated with hypertension incidence.
146

Association of Lipid Levels With the Prevalence of Hypertension in Chinese Women: A Cross-Sectional Study Based on 32 Health Check Centers

Deng, Guizhi, Li, Yunjie, Cheng, Wenke 19 October 2023 (has links)
Background: Dyslipidemia is strongly associated with the development of hypertension. In our previous study, it was shown that elevated TC, LDL-c, and non-HDL-c were associated with the prevalence of hypertension in Chinese men, whereas the relationship between HDL-c and hypertension shifted from no association to a positive association after adjusting for the BMI. To further accumulate epidemiological evidence in Asian women, this study aimed to investigate the relationship between lipid profile and prevalence of hypertension in Chinese adult women. Methods: This is a cross-sectional study including 54,099 Chinese women aged>20 years at 32 health screening centers in 11 cities from 2010-2016. The original data were obtained from DATADRYAD database (www.datadryad.org). Besides, the overall women were classified into non-hypertensive and hypertensive groups based on baseline blood pressure levels. Differences between the two groups were examined by Man-Whitney test or Chi-square test. Spearman’s correlation coefficient was employed to evaluate the correlation between systolic blood pressure (SBP), diastolic blood pressure (DBP) and lipid profiles. Multivariate logistic regression was performed to estimate the relationship between different lipid levels and the prevalence of hypertension. Odds ratios (ORs) and 95% confidence intervals (CIs) indicated the risk of lipid and hypertension. Bayesian model (BN) model was constructed to further assess the relationship between baseline characteristics and the prevalence of hypertension, as well as the importance of each variable for the prevalence of hypertension. Results: Compared to the non-hypertensive population, the hypertensive population was older, and had the higher body mass index (BMI), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), serum creatinine (Scr), fasting blood glucose (FPG), blood urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and non-high-density lipoprotein cholesterol (non-HDL-c), but HDL-c and the presence concerning the family history of diabetes were lower. Multivariate logistic regression analysis revealed that TC, LDL-c, and non-HDL-c showed a positive trend with hypertension risk (p for trend < 0.05) whereas TC and HDL-c were not significantly associated with hypertension prevalence. Moreover, each 1 mg/dl increase in TC, LDL, and non-HDL hypertension prevalence increased by 0.2% [1.002 (1.000-1.003)], 0.2% [1.002 (1.000- 1.004)], and 0.2% [1.002(1.001-1.004)], respectively. BN suggested that the importance of age, BMI, FPG, non-HDL-c on the prevalence of hypertension was 52.73%, 24.98%, 11.22%, and 2.34%, respectively. Conclusion: Overall, in Chinese adult women, TC, LDL-c and non-HDL-c levels were higher and HDL-c level was lower in the hypertensive population, whereas TG did not differ significantly from the non-hypertensive population. Meanwhile, TC, LDL-c, and non-HDL-c were positively associated with prevalence of hypertension, and HDL-c was negatively associated with prevalence of hypertension but became nonsignificant after full adjustment for variables. Moreover, BN model suggested that age, BMI, FPG, and non-HDL-c had a greater effect on the development of hypertension.
147

Weibull Modulus of Hardness, Bend Strength, and Tensile Strength of Ni-Ta-Co-X Metallic Glass Ribbons

Neilson, Henry Jathuren 12 June 2014 (has links)
No description available.
148

A Nonlinear Constitutive Model for High Density Polyethylene at High Temperature

Rajasekaran, Nepolean 20 April 2011 (has links)
No description available.
149

Apolipoprotein A-I Self-Association and the Formation of High Density Lipoprotein

Topbas, Celalettin 17 September 2015 (has links)
No description available.
150

Comparison between field and analytical results on the structural performance of deeply buried 42&60-inch diameter high density polyethylene pipes

AL Tarawneh, Bashar K. January 2002 (has links)
No description available.

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