It is presently believed that brown adipose tissue (BAT) is an important tissue in the control of obesity because it has the propensity to increase energy expenditure. The purpose of this study was to attempt to quantify the thermogenesis of BAT when four rats were exposed to a progression of low-fat to high-fat diet. Exogenous norepinephrine (NE) injections (dose of 0.25 mg/kg i.p.) were administered in order to elicit a temperature response, where increases in temperature indicate increased activity. Temperatures were measured via temperature sensing transponders that had been inserted at the following three sites: interscapular BAT (iBAT), the abdomen (core), and lower back (reference). Data showed increased BAT activity during acute (2-3 weeks) high fat diet (HFD) in comparison to low fat diet (LFD), but a moderate to marked decrease in BAT activity during chronic HFD (6-8 weeks) when compared to acute HFD. This suggests that while a HFD may initially stimulate BAT in the short-term, a long-term HFD diet may have negative effects on BAT activation.

Type II diabetes is a serious, chronic metabolic disease that has serious impacts on both the health and quality of life in patients diagnosed with the disease. Type II diabetes is also a very prevalent disease both in the United States and around the world. There is still a lot that is unknown about Type II diabetes, and this study will aim to answer some of these questions. The question posed in this study is whether insulin resistance changes as a function of time after the start of a high fat diet. We hypothesized that peripheral insulin resistance would be observed in animals placed on a high fat diet; and peripheral insulin resistance would have a positive correlation with time. In order to test the hypotheses, four Sprague-Dawley male rats were placed on a high fat diet for 8 weeks, during which time they were subjected to three intraperitonal insulin tolerance tests ((NovoLogTM 1 U/kg). These three tests were conducted at baseline (week 1), week 4, and week 8 of the high fat diet. The test consisted of serially determining plasma glucose levels via a pin prick methodology, and exposing a droplet of blood to the test strip of a glucometer (ACCUCHEKTM, Roche Diagnostics). Two plasma glucose baselines were taken, and then every 15 minutes following insulin injection for one hour. Glucose disposal rates were then calculated by simply dividing the glucose levels at each time point by the baseline value, and multiplying by 100. Area under the curve data was calculated via definite integral. The area under the curve data was then subjected to a single analysis of variance (ANOVA), with a statistical significance threshold of p<0.05. The results of the study did not indicate the development of peripheral insulin resistance in the animals placed on a high fat diet. Insulin-mediated glucose disposal was about 50% at 30 minutes in all four animals, during all three testing periods. Furthermore, the ANOVA resulted in p=0.92, meaning that the data was not statistically significant. In conclusion, peripheral insulin resistance was not observed in the animals, meaning no determination could be made on the relation between time and insulin resistance.

Revision hip procedures represent a large financial burden on hospitals and the problem will continue to worsen as the baby boomer generation ages and life expectancy goes up. The future problem is a complex issue that bridges scientific and anecdotal evidence and must be solved. A review of the current total hip arthroplasty procedure in regards to the physical properties of the materials used for hip prostheses is given. Revision procedures can be caused by infection or basic wear and tear from the stress that that implant is subjected to daily. Infections on these implants often present themselves as medical biofilms. The mechanisms of biofilm formation include a complex system of enzymes that work to initiate a phenotypic response based on an established quorum sensing within the colony of bacteria. Surgical methods to treat infection include irrigation and debridement as well as loading drug cement spacers with antimicrobial in hopes of delivering the antibiotic locally. Research is being done to better model the transport of drug through the tissue surrounding the implant, and will hopefully one day be available for use in individual patients.

Concurrent with the epidemic of childhood obesity (17% of adolescents), an unprecedented world-wide increase in the prevalence of several adiposity-related complications (including fatty liver disease (hepatic steatosis), type 2 diabetes and early cardiovascular disorders) in this age group, has emerged. Two principle environmental variables play an essential role in the development and maintenance of obesity and in disturbing glucose homeostasis: a lack of physical exercise and overnutrition, i.e., high carbohydrate and high fat diets (HFD). It was our laboratory's intention to develop a rodent model to examine whether the metabolic instability observed in human pubertal children is also present in maturing rats and whether a HFD during this maturational period enhances adipose-related complications with or without an increase in body weight. We hypothesized that maturing Sprague-Dawley rats would reveal a profile of metabolic disturbances and that a disruption of the hyperbolic arrangement between insulin sensitivity and insulin release would be evident (statistically significant changes in fasting hyperinsulinemia, insulin resistance, and insulin release) indicating a high risk environment for future cardiometabolic diseases. It was observed that pubertal rats are metabolically impaired and that a HFD substantially enhances metabolic deficits with marked disturbance in insulin sensitivity (hyperinsulinemia). Additionally, substantial lipogenesis was observed in visceral and liver tissue, potentially as a result of hyperinsulinemia. Both phenotypes of maturing rats exposed to a HFD (obesity prone and obesity resistant) demonstrated "metabolic obesity" regardless of physical phenotype. These outcomes have relevance in the context of public health, particularly if lipocentricity is viewed as an essential element in the challenge of preventing and/or treating perturbations to the metabolic health of pubertal children.

Diabetes is a growing epidemic in developing countries, specifically in rural Kenya. In addition to the high cost of glucose testing, many diabetics in Kenya do not understand the importance of testing their blood glucose, let alone the nature of the disease. This project addresses the insufficiency of educational materials regarding diabetes in rural Kenya. The resulting documents can easily be adjusted for use in other developing countries.

Growing concern over health risks associated with environmental contaminants has prompted an increase in the search for effective detection methods. The available options provide acceptable sensitivity and specificity, but with high purchase and maintenance costs. Herein, a low-cost, portable environmental contaminant sensor was developed using electrochemical techniques and an efficient hydrogel capture mechanism. The sensor operates with high sensitivity and maintains specificity without the added requirement of extensive electrode modification. Rather, specificity is obtained by choosing specific potential regions in which individual contaminants show reduction or oxidation activity. A calibration curve was generated showing the utility of the sensor in detecting gas compounds reliably in reference to a current state of the art sensor. Reusability of the sensor was also demonstrated with a cyclic exposure test in which response reversibility was observed. As such, the investigated sensor shows great promise as a replacement technology in the current environmental contaminant detector industry.

Sickle Cell Disease (SCD) is a prevalent genetic disease in Africa, and specifically in Kenya. The lack of available relevant disease education and screening mean that most don't understand the importance of getting testing and many children die before they can get prophylactic care. This project was designed to address the lack of knowledge with supplemental educational materials to be partnered with an engineering capstone project that provides a low cost diagnostic test.

Improving medical aerosols is the multifaceted objective that is the overarching theme of this work. This thesis is the culmination of many hours of academic research. It details the current mechanical and physiological obstacles of state of the art drug inhalation technology, as well as provides a detailed guide of the experimental set up, procedure, analysis and background for the charge neutralization experiments performed by the author. The findings of this research are that inhalation devices need to become personalized; meaning adjustable flow rates, particle sizes, and charge levels. To improve the efficiency of lung deposition they could use MRI to take advantage of 3D modeling software to make transport models of an individual patient's lungs. This model would allow an engineer to calculate the air velocity in each passage of the respiratory system and would account for any pulmonary obstructions that would completely alter the deposition pattern from the average healthy patient. With the velocity profile of the lung a doctor could formulate an aerosol with the perfect attributed for the most targeted delivery. For the experiments performed in this work the following results were obtained. The ionization of air by polonium 210 alpha particles is dependent on the distance from the alpha emitting source and the strength of the electric field. Furthermore discharge of aerosol droplets is possible through volume conduction however the mass of the polonium 210 isotope must be proportional to the ionization current demand.

Intracranial aneurysms are blood \u2014filled sacs along the blood vessels in the brain. These aneurysms can be particularly dangerous due to difficulty in detection and potential lifethreatening outcome. When these aneurysms are detected, there are few treatment options to prevent rupture, one of which is endovascular stents. By placing a stent across the parent vessel, blood flow can be diverted from the aneurysm. Reduced flow reduces the chance of rupture and promotes clotting within the aneurysm. In this study, hemodynamics in idealized basilar tip aneurysm models were investigated at three flow rates using particle imaging velocimetry (PIV). Two models were created with increasing dome size (4mm vs 6mm), and constant dome-to-neck ratio (3:2) and parent vessel contact angle to represent growing aneurysm. With the pulsatile flow, data is acquired at three separate points in the cardiac cycle. Both of the models were studied untreated, treated with Enterprise stent and treated with Pipeline stent. Enterprise stent was developed mainly for structural support while the Pipeline stent was developed as a flow diverter. Due to target functions of the stents, Enterprise stent is more porous than the Pipeline stent. Hemodynamics were studied using a stereo particle image velocimetry technique. The flow in models was characterized by neck and aneurysmal RMS velocity, neck and aneurysm kinetic energy, cross neck flow. It was found that both of the stents are capable diverting flow. Enterprise reduced aneurysmal RMS velocity in model 1 by 38.7% and in model 2 by 76.2%. Pipeline stent reduced aneurysmal RMS velocity in model 1 by 71.4% and in model 2 by 88.1%. Both reductions are data for 3ml/s at peak systole pulsatile flow. Data shows that the Pipeline stent is better than Enterprise stent at reducing flow to the aneurysm.