The physical properties (i.e., mass, particle diameter and composition) of apolipoprotein B (apoB)-containing lipoproteins (apoB-LP) are a major determinant of atherosclerotic cardiovascular disease (ASCVD) risk. The objective of this research was to investigate how nascent apoB-LP physical properties affect circulating lipoprotein profiles and risk of disease. Relationships between apoB-LP physical properties and arterial plaque formation in four genotypes of mice with apoB isoform specific clearance defects were investigated. Multivariate statistical analysis found that arterial lesions were most closely related to genetic background and apoB concentration related to delayed clearance rate. For defining the dietary effects on circulating lipoprotein profiles, the physical properties of lipoproteins in hamsters fed high-carbohydrate diets containing either 60% fructose or 60% cornstarch for 2 wk were studied. Fructose increased very low-density lipoprotein (VLDL) particle diameter and decreased low-density lipoprotein (LDL) particle diameter. Elevations in all high-density lipoprotein (HDL) fractions were observed in the fructose-fed group. Further investigation was made of whether changes to the physical properties in circulating lipoproteins resulted from changes to nascent particles in the assembly and secretion processes. Intermediate particles used for lipoprotein assembly were isolated from rough endoplasmic reticulum of hamster liver, and nascent VLDL were isolated from plasma after Triton WR-1339 injection of hamsters. A large, TG-rich apoB-deficient particle and a small, lipid-poor apoB-containing particle were isolated in each dietary setting. The diameter of first-step particles was larger in fructose feeding, which indicated that apoB degradation decreases and provides the basis for apoB oversecretion. Fructose feeding significantly increased the concentrations recovered from liver for these two particles and for nascent particles compared with chow or starch feeding. Collectively, these results demonstrate: 1) genetic factors can dictate metabolism, and metabolic conditions can critically affect the physical properties and further atherogenicity of apoB-LP; 2) changes in physical properties of circulating apoB-LP are derived from changes to the nascent particles; and 3) dietary factors can influence the assembly, secretion, and metabolism of apoB-LP. The findings of the research may provide a metabolic basis for the recognition of new targets that could regulate apoB-LP metabolism to prevent and treat ASCVD.

Chickpea is a food legume crop grown in tropical, sub-tropical and temperate regions. World chickpea production is roughly three times that of lentils. Among pulse crops marketed as human food, world chickpea consumption is second only to dry beans. Turkey, Australia, Syria, Mexico, Argentina and Canada are major chickpea exporters. There are two types of chickpea, namely, the kabuli and the desi. The kabuli type is grown in temperate regions while the desi type chickpea is grown in the semi-arid tropics. Chickpea is valued for its nutritive seeds with high protein and starch content. They are eaten fresh as green vegetables, parched, fried, roasted, and boiled, as snack food, dessert and condiments. The seeds are ground and the flour can be used in soup, dhal and bread. Cooked chickpea is mostly preferred by consumers, especially the kabuli type. In this thesis, the heat and moisture transfer behavior of kabuli chickpea when subjected to cooking at different temperatures was investigated. The thermo-physical properties of chickpea were studied to develop a model to simulate the temperature distribution and moisture absorption in a chickpea seed when cooked in water. The thermo-physical properties determined experimentally were thermal conductivity, specific heat, moisture diffusivity, particle density and moisture content. Thermal diffusivity was calculated using the experimental values of thermal conductivity, specific heat and density. The water absorption in chickpea was determined when the seeds were soaked at different temperatures. It was observed that as the temperature of the soaking medium was increased, the rate of moisture absorption also increased. Soaking was done to enhance the gelatinization process during cooking. Cooking experiments were conducted for boiling temperatures ranging from 70 to 98°C for both soaked and unsoaked seeds. It resulted in the soaked seeds being cooked within 40-50 min, whereas the unsoaked seeds took around 250-300 min to cook. The amount of soluble solids lost during the cooking process is also reported which enables to predict the optimum soaking and cooking temperature. Using linear regression simple models for dependency of thermal conductivity, specific heat, thermal diffusivity and density on temperature and moisture content were developed. The rate of moisture transfer and the center temperature in the seed during cooking was determined experimentally and also simulated with the constant thermal properties found experimentally. The closeness of the simulated and experimental results was proved by appropriate statistical analysis. Based on the results obtained, it can be understood that soaking the chickpea seeds at temperatures ranging from 25 to 40°C for 8 h and cooking it at higher temperatures ranging from 90 to 100°C will improve the quality of the cooked seed with minimum mass loss. This optimum condition saves both energy and time.

Thermoelectric materials are the only known materials capable of direct conversion of a heat gradient into electricity (Seebeck effect) or vice-versa (Peltier effect). Thermoelectric (TE) devices are comprised of solid-state p-type and n-type semiconductors paired in an electrical circuit and exposed to a temperature gradient. The effectiveness of the materials is evaluated based on the mathematical term ZT=T∙S^2 σ/κ: S represents the Seebeck coefficient; σ represents the electrical conductivity; κ is the thermal conductivity; and T is the average of the coldest and hottest regions of the applied gradient. This ZT term is larger for better materials; most modern devices in use to-date display ZT values on the order of one. A large temperature gradient combined with a large Z term will lead to a high-performance TE material that involves no waste, no side product, and no requirement for moving parts. Discovery and optimization of new thermoelectric materials is a critical component of current thermoelectric research. As such, researchers are constantly searching for a new material that has the following properties: the ability to withstand higher temperatures, thus maximizing the T term; exhibit a large Seebeck coefficient and electrical conductivity through doping techniques; and present minimal thermal conductivity, κ. In recent years, research attention has moved from S^2σ to κ, which can be optimized through a variety of techniques including complex crystal structure, heavy element inclusion, and introduction of structural defects such as nanodomains/nanostructuring. Due to their tendency to form complex crystal structures and bonding, Te-based materials have become popular targets for TE research and optimization. Compounds with Te anions that also include other heavy elements such as alkali (A) metals, alkaline earth (R) elements, or heavy p-block elements including the triels (Tr), tetrels (Tt), or pnictogens (Pn) have become a principal source of new and ground-breaking thermoelectric materials. Likewise, optimization of existing TE materials with these aforementioned compositions has led to ZT values twice those of the materials' original reports. Of the known TE materials, Bi2Te3 is one of the staples in the field. It shows narrow band-gap semiconducting properties that can be tuned to p- or n-type values based on the impurities introduced, and its κ values are inherently low due to the presence of heavy elements and their structural layering motifs. A series of compounds, (SnTe)x(Bi2Te3)y, based on this idea can be produced via the alteration of x:y. In this work, several of these compounds are introduced and studied as potentially useful thermoelectric materials: SnBi2Te4, SnBi4Te7, and SnBi6Te10 are the major targets because of their systematic layering motifs and complex structures. Phase range studies, crystal structure (Rietveld) refinements, and synthesis optimizations were commenced to ensure that the materials were well-characterized and produced phase-pure before the attempted ZT improvements. By altering the quantity of active charge carriers in these systems, changes in ZT can be observed – this is achieved through doping with, primarily, heavy Tr elements Ga, In, and Tl. Thusly, the physical properties are measured and compared for a number of series: [Tr]xSn1-xBi2Te4, [Tr]xSnBi2-xTe4, [Tr]xSn1-xBi4Te7, [Tr]xSnBi4-xTe7, [Tr]xSn1 xBi6Te10, and [Tr]xSnBi6-xTe10. Of the triels, Tl is the largest useful element in the group and is known for showing both Tl+ and Tl3+ cationic states and, in thermoelectric applications, for possessing uniquely low κ values. Thallium telluride compounds such as Tl5Te3 are therefore quite relevant to this field. The family of compounds includes Tl9BiTe6 – one of the better materials with ZT = 1.2 (500 K) using a hot-pressed pellet. Herein, the system is expanded to include Tl10-xSnxTe6 which shows good TE potential with ZT(Tl7.8Sn2.2Te6) = 0.6 (617 K) with a cold-pressed pellet. The incorporation of tetrel elements is investigated through measurements on Tl10-x-ySnxBiyTe6 and also applies to the lesser-studied Tl9SbTe6 compound via research on the systems Tl9SnxSb1 xTe6 and Tl9PbxSb1 xTe6. Tl is studied in three concentrations with Tl10 x ySnxBiyTe6: Tl9…, Tl8.67…, and Tl8.33…, with varying Sn:Bi at each increment. Tt elements are systematically added to the Tl9[Tt]xSb1 xTe6 structure with 0.0 ≤ x ≤ 0.7. Crystallographic studies, electronic structure calculations, and physical properties are explored for each series. Due to Te’s ability to form complex Te–Te interactions in certain environments, the combination of alkaline earth metals, namely R = Ba, with the coinage metals (Cg = Cu, Ag), chalcogenides (Q = S, Se), and Te, form a plethora of previously unknown crystal structures. Many of these are Zintl-phase narrow-band gap semiconductors with complex Cg–Cg and Q–Q bonding schemes – combined with their heavy element incorporation, the family is of great interest to the thermoelectrics community. Within this thesis, three new crystal systems are presented: Ba3Cu17-x(Se,Te)11; Ba3Cu17-x(S,Te)11 and Ba3Cu17-x(S,Te)11.5; and Ba2Cu7-xTe6. All structures show Cu-deficiencies in their crystal structures with d10–d10 interactions and 3-dimensional networks of the Cg metal. The chalcogenide elements in the structures display unique Q–Q or Te–Te bonding of varying dimensionality. The electronic structures and bonding calculations are reported for each compound, as are the single crystal studies. The first two of the aforementioned compounds are narrow-band gap semiconductors, whereas the latter two display metallic behaviour.

Chickpea is a food legume crop grown in tropical, sub-tropical and temperate regions. World chickpea production is roughly three times that of lentils. Among pulse crops marketed as human food, world chickpea consumption is second only to dry beans. Turkey, Australia, Syria, Mexico, Argentina and Canada are major chickpea exporters. There are two types of chickpea, namely, the kabuli and the desi. The kabuli type is grown in temperate regions while the desi type chickpea is grown in the semi-arid tropics. Chickpea is valued for its nutritive seeds with high protein and starch content. They are eaten fresh as green vegetables, parched, fried, roasted, and boiled, as snack food, dessert and condiments. The seeds are ground and the flour can be used in soup, dhal and bread. Cooked chickpea is mostly preferred by consumers, especially the kabuli type. In this thesis, the heat and moisture transfer behavior of kabuli chickpea when subjected to cooking at different temperatures was investigated. The thermo-physical properties of chickpea were studied to develop a model to simulate the temperature distribution and moisture absorption in a chickpea seed when cooked in water. The thermo-physical properties determined experimentally were thermal conductivity, specific heat, moisture diffusivity, particle density and moisture content. Thermal diffusivity was calculated using the experimental values of thermal conductivity, specific heat and density. The water absorption in chickpea was determined when the seeds were soaked at different temperatures. It was observed that as the temperature of the soaking medium was increased, the rate of moisture absorption also increased. Soaking was done to enhance the gelatinization process during cooking. Cooking experiments were conducted for boiling temperatures ranging from 70 to 98°C for both soaked and unsoaked seeds. It resulted in the soaked seeds being cooked within 40-50 min, whereas the unsoaked seeds took around 250-300 min to cook. The amount of soluble solids lost during the cooking process is also reported which enables to predict the optimum soaking and cooking temperature. Using linear regression simple models for dependency of thermal conductivity, specific heat, thermal diffusivity and density on temperature and moisture content were developed. The rate of moisture transfer and the center temperature in the seed during cooking was determined experimentally and also simulated with the constant thermal properties found experimentally. The closeness of the simulated and experimental results was proved by appropriate statistical analysis. Based on the results obtained, it can be understood that soaking the chickpea seeds at temperatures ranging from 25 to 40°C for 8 h and cooking it at higher temperatures ranging from 90 to 100°C will improve the quality of the cooked seed with minimum mass loss. This optimum condition saves both energy and time.

No description available.

No description available.

Many processes in the ocean are interrelated. The direction with which an eddy rotates will determine if nutrients are moved closer to the surface where they can be utilized by plankton to increase the base of the food chain, or it can restrict growth by causing the surface layer of nutrient poor water to deepen below the photic layer. The direction of current flow will also affect the temperature structure, which is a contributing factor in the density of water. A change in density can act as a barrier between the surface and deeper waters, effectively isolating the surface from deep waters. It is important to understand the physical properties in a study area in order to understand the dynamics controlling the distributions of nutrients, which influence the distribution of plankton, which influences the distribution of predator species like squid and whales. The Sperm Whale Seismic Study (SWSS) tracked the locations of sperm whales in the Gulf of Mexico. This study seeks to describe the physical environment in which they live. To that end, various physical properties observed during the SWSS cruises were processed and used in conjunction with sea surface height (SSH) fields from satellite altimetry data. The data from different years and from the same years are used to provide descriptions of the physical environment present during the SWSS cruises and how that environment changed between cruises. A time-series of currents, collected over a six month time period in 2006, is included to document how the currents are influenced by different processes found along the continental slope in the northern Gulf of Mexico. The findings indicate the observed currents are related to local SSH features. Temperature structure can be influenced throughout the upper 1000 m by these SSH features. The temperature structure is stable over time but depends on local SSH features. Properties nearer to the surface are more variable than at depth. Although the overlying wind field most likely influences the currents at 51 m no correlation between winds observed at the Brutus platform and currents observed at 51 m at the Ocean Star platform was found.

Modules for cotton storage and transport should be constructed with a shape that will resist collecting water to maintain the quality of seed cotton during storage. Meeting this specification requires knowledge of the relationship between the applied compressive force, deformation, and time for seed cotton. Several factors were tested to determine their effects on the height and density of seed cotton during compression, creep loading, and recovery. Models were used to describe these processes. These results were used to develop an algorithm capable of providing information on module shape to the module builder operator. The initial loading density did not affect the compressed density, but a slight effect was observed in the recovered density, due to the weight of the seed cotton. Picker harvested cotton was compressed to a greater density than stripper harvested cotton, but expanded more during recovery, resulting in similar final densities. Multiple compressions increased the density, but this increase was not physically significant after the third compression. Higher moisture content increased the density seed cotton could be compressed to slightly. Viscoelastic behavior was observed; however, the effect on density was small. Both the compression and creep curves were described using mathematical models. A compression model using an asymptotic true strain measure yielded high R2 values; however, some aspect of this process remained unexplained and the equation was limited in its predictive ability. Creep behavior was described using a modified Burgers model. This model was more accurate than the creep model, although a definite trend existed in the creep model residuals. A feedback algorithm was developed based on the observation that the compressed density was primarily dependent on the mass of seed cotton and not the initial density. By measuring the compressed depth of cotton in a module and the hydraulic pressure of the tramper foot cylinder, the resulting shape of the module can be predicted. Improved loading of the module builder is necessary to produce a desirably shaped module. More seed cotton needs to be placed in the center of the module, resulting in a surface that slopes down towards the outer edges.

The physical properties (i.e., mass, particle diameter and composition) of apolipoprotein B (apoB)-containing lipoproteins (apoB-LP) are a major determinant of atherosclerotic cardiovascular disease (ASCVD) risk. The objective of this research was to investigate how nascent apoB-LP physical properties affect circulating lipoprotein profiles and risk of disease. Relationships between apoB-LP physical properties and arterial plaque formation in four genotypes of mice with apoB isoform specific clearance defects were investigated. Multivariate statistical analysis found that arterial lesions were most closely related to genetic background and apoB concentration related to delayed clearance rate. For defining the dietary effects on circulating lipoprotein profiles, the physical properties of lipoproteins in hamsters fed high-carbohydrate diets containing either 60% fructose or 60% cornstarch for 2 wk were studied. Fructose increased very low-density lipoprotein (VLDL) particle diameter and decreased low-density lipoprotein (LDL) particle diameter. Elevations in all high-density lipoprotein (HDL) fractions were observed in the fructose-fed group. Further investigation was made of whether changes to the physical properties in circulating lipoproteins resulted from changes to nascent particles in the assembly and secretion processes. Intermediate particles used for lipoprotein assembly were isolated from rough endoplasmic reticulum of hamster liver, and nascent VLDL were isolated from plasma after Triton WR-1339 injection of hamsters. A large, TG-rich apoB-deficient particle and a small, lipid-poor apoB-containing particle were isolated in each dietary setting. The diameter of first-step particles was larger in fructose feeding, which indicated that apoB degradation decreases and provides the basis for apoB oversecretion. Fructose feeding significantly increased the concentrations recovered from liver for these two particles and for nascent particles compared with chow or starch feeding. Collectively, these results demonstrate: 1) genetic factors can dictate metabolism, and metabolic conditions can critically affect the physical properties and further atherogenicity of apoB-LP; 2) changes in physical properties of circulating apoB-LP are derived from changes to the nascent particles; and 3) dietary factors can influence the assembly, secretion, and metabolism of apoB-LP. The findings of the research may provide a metabolic basis for the recognition of new targets that could regulate apoB-LP metabolism to prevent and treat ASCVD.

No description available.