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Strategies To Resolve The Three-Dimensional Structure Of The Genome Of Small Single-Stranded Icosahedral Viruses, Eduardo Sanz Garcia Dec 2010

Strategies To Resolve The Three-Dimensional Structure Of The Genome Of Small Single-Stranded Icosahedral Viruses, Eduardo Sanz Garcia

Theses and Dissertations

The aim of this study is the three-dimensional structural characterization of the genome packaging inside viral capsids via cryo-electron microscopy and three-dimensional reconstruction. The genome of some single-stranded viruses can be densely packaged within their capsid shells. Several stretches of the genome are known to adopt stable secondary structures, however, to date, little is known about the three-dimensional organization of the genome inside their capsid shells. Two techniques have been developed to facilitate the structural elucidation of genome packaging: the asymmetric random-model method, and the symmetry-mismatch, random model method. Both techniques were successfully tested with model and experimental data. The …


Gender And Color Specific Differences In Event Related Potentials, Abhishek Trikha Dec 2010

Gender And Color Specific Differences In Event Related Potentials, Abhishek Trikha

Theses and Dissertations

This project analyzed gender and color-specific differences in event-related potentials (ERPs). Previous studies have shown that males process color differently than females. In a recent study, sex differences were found in ERPs during a visual object recognition task. There were higher EEG amplitudes in females (especially P300) than males. Significant sex and color-specific differences have been found in diseases involving altered dopamine (DA) machinery. Thus, we analyzed differences between ERPs in males vs females during a color task. We also compared the color-specific differences in ERPs between males and females. Males and females participated in EEG recording sessions for 2 …


The Effects Of Chronic Ampk Activation On Hepatic Triglyceride Accumulation And Glycerol-3-Phosphate Acyltransferaseactivity With High Fat Feeding, Mary E. Curtis Dec 2010

The Effects Of Chronic Ampk Activation On Hepatic Triglyceride Accumulation And Glycerol-3-Phosphate Acyltransferaseactivity With High Fat Feeding, Mary E. Curtis

Theses and Dissertations

High fat feeding increases hepatic fat accumulation and is associated with hepatic insulin resistance. AMP Activated Protein Kinase (AMPK) is thought to inhibit lipid synthesis by the acute inhibition of glycerol-3-phosphate acyltransferase (GPAT) activity and transcriptional regulation via SREBP-1c. The purpose of this study was to determine if chronic activation of AMPK prevented an increase in GPAT1 activity in rats fed a high fat diet. Rats were fed a control (C), or a high fat (HF) diet (60% fat) for 6 weeks and injected with saline or a daily AICAR dose of 0.5 mg/g body weight. Chronic AMPK activation by …


The Effect Of Passive Stretching And Isometric Contractions On Delayed Onset Muscle Soreness After A Typical Bout Of Exercise, John W. Gibson Dec 2010

The Effect Of Passive Stretching And Isometric Contractions On Delayed Onset Muscle Soreness After A Typical Bout Of Exercise, John W. Gibson

Theses and Dissertations

Delayed Onset Muscle Soreness (DOMS) is a common response to activities involving lengthening contractions. Muscle inflammation is associated with DOMS and may play an integral role in protecting a muscle from damage and soreness in response to subsequent bouts of lengthening contractions. Research in animals has shown that prior exposure to passive stretching and isometric contractions of a muscle resulting in muscle inflammation attenuates the muscle inflammatory response following subsequent bouts of lengthening contractions. The purpose of this study was to determine whether passive stretching and isometric contractions in humans would reduce DOMS following a typical bout of resistance exercise. …


Chemical Vapor Deposition Of Silanes And Patterning On Silicon, Feng Zhang Dec 2010

Chemical Vapor Deposition Of Silanes And Patterning On Silicon, Feng Zhang

Theses and Dissertations

Self assembled monolayers (SAMs) are widely used for surface modification. Alkylsilane monolayers are one of the most widely deposited and studied SAMs. My work focuses on the preparation, patterning, and application of alkysilane monolayers. 3-aminopropyltriethoxysilane (APTES) is one of the most popular silanes used to make active surfaces for surface modification. To possibly improve the surface physical properties and increase options for processing this material, I prepared and studied a series of amino silane surfaces on silicon/silicon dioxide from APTES and two other related silanes by chemical vapor deposition (CVD). I also explored CVD of 3-mercaptopropyltrimethoxysilane on silicon and quartz. …


The Relationship Between Diet Quality And Body Composition In College Women: A Cross-Sectional Analysis, Annette Elisabeth Perkins Dec 2010

The Relationship Between Diet Quality And Body Composition In College Women: A Cross-Sectional Analysis, Annette Elisabeth Perkins

Theses and Dissertations

Objective. Determine the relationship between dietary quality and body weight/composition in college women. Specific emphasis was made regarding adherence to current MyPyramid guidelines, fruit, vegetable and junk food consumption.

Design/Participants. The study used a cross-sectional design. One hundred and sixty three women were recruited to participate in the study. All participants were university students (20.4 ± 1.6 y). Diet intake was measured using the Dietary History Questionnaire (DHQ) and the Healthy Eating Index (HEI) was calculated to assess diet quality. Body fat percentage was assessed using the Bod Pod and BMI was calculated using height and weight measurements. Physical activity …


The Effects Of Whole Body Vibration On Strength Gains In The Bench Press, The Back Squat, And The Power Clean In Division I Football Players, Kelly S. Poppinga Dec 2010

The Effects Of Whole Body Vibration On Strength Gains In The Bench Press, The Back Squat, And The Power Clean In Division I Football Players, Kelly S. Poppinga

Theses and Dissertations

The purpose of this study was to determine if whole body vibration effects strength gains in the bench press, the back squat, and the power clean in division 1 football players. Thirty-one NCAA Division 1 male football players volunteered for this study and were randomly assigned to a control group (C=16) or one of two vibration groups (V1=7, V2=8). Subjects followed the training program for eight weeks. A pre-test, mid-test, and post-test one repetition max was measured at 0, 4, and 8 weeks for the bench press, the back squat, and the power clean. A 3x3 factorial ANOVA revealed varied …


Gene Flow And Dispersal Of The Flatworm, Polycelis Coronata: A Multiscale Analysis, Jeffrey N. Moore Dec 2010

Gene Flow And Dispersal Of The Flatworm, Polycelis Coronata: A Multiscale Analysis, Jeffrey N. Moore

Theses and Dissertations

We determined genetic variance and gene flow across multiple scales (reaches, headwater segments, and catchments) to examine the dispersal ability of the flatworm Polycelis coronata along the Wasatch Mountains of Utah. Multiple models predict patterns of genetic differentiation in stream invertebrates based on dispersal traits and the spatial connectivity of the habitat. The stream hierarchy model predicts genetic differentiation to be low and gene flow to be high between reaches nested in segments, moderate among segments within catchments, and differentiation to be highest and gene flow lowest among catchments, whereas the headwater model predicts the greatest differentiation between headwater segments. …


Measured And Estimated Ground Reaction Forces For Multi-Segment Foot Models, Dustin A. Bruening, Kevin M. Cooney, Frank L. Buczek Dec 2010

Measured And Estimated Ground Reaction Forces For Multi-Segment Foot Models, Dustin A. Bruening, Kevin M. Cooney, Frank L. Buczek

Faculty Publications

Accurate measurement of ground reaction forces under discrete areas of the foot is important in the development of more advanced foot models, which can improve our understanding of foot and ankle function. To overcome current equipment limitations, a few investigators have proposed combining a pressure mat with a single force platform and using a proportionality assumption to estimate subarea shear forces and free moments. In this study, two adjacent force platforms were used to evaluate the accuracy of the proportionality assumption on a three segment foot model during normal gait. Seventeen right feet were tested using a targeted walking approach, …


High Flow Air Sampling For Field Detection Using Gas Chromatography-Mass Spectrometry, Jacolin Ann Murray Dec 2010

High Flow Air Sampling For Field Detection Using Gas Chromatography-Mass Spectrometry, Jacolin Ann Murray

Theses and Dissertations

The ability to rapidly detect and identify hazardous analytes in the field has become increasingly important. One of the most important analytical detection methods in the field is gas chromatography-mass spectrometry (GC-MS). In this work, a hand-portable GC-MS system is described that contains a miniature toroidal ion trap mass analyzer and a low thermal mass GC. The system is self-contained within the dimensions of 47 x 36 x 18 cm and weighs less than 13 kg. Because the instrument has a small footprint, it was used as the detector for an automated near-real-time permeation testing system. In permeation testing, materials …


Conditions Associated With Clostridium Sporogenes Growth As A Surrogate For Clostridium Botulinum In Non-Thermally Processed Canned Butter, Reed H. Taylor Nov 2010

Conditions Associated With Clostridium Sporogenes Growth As A Surrogate For Clostridium Botulinum In Non-Thermally Processed Canned Butter, Reed H. Taylor

Theses and Dissertations

Shelf-stable canned butter is currently available in retail stores, and many home-preservationists promote home-canning of butter. Non-cultured butter is a low-acid canned food, which would presumably require thermal processing. The lack of a thermal process step in canned butter products raises questions of potential safety, because they are hermetically sealed and generally exhibit anaerobic growth conditions, which are optimal for Clostridium botulinum growth. Without thermal processing, low-acid canned foods (LACF) must have inhibitory factors present to prevent C. botulinum growth. Some potential intrinsic inhibitory factors, or "hurdles", within butter include: reduced water activity (aw), acidity (pH) in cultured products, elevated …


Antimicrobial And Anticancer Activity Of Essential Oils From Guatemalan Medicinal Plants, Andrew B. Miller Nov 2010

Antimicrobial And Anticancer Activity Of Essential Oils From Guatemalan Medicinal Plants, Andrew B. Miller

Theses and Dissertations

Guatemalan medicinal plants were collected and screened for the presence of essential oils using steam distillation. Oil was found in 63 species from 24 families and was tested in tube dilution assays for activity against Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Lactobacillus acidophilus and Candida albicans. Several essential oils were highly active with 20 instances of oils inhibiting the microbes at an MIC of 0.31 µl/ml. Oils were also tested against cancerous and established cell lines using a 15% (v/v) agar-media which was developed to improve essential oil solubility. Assays were performed against three cancer lines: …


Proteoliposome Proton Flux Assays Establish Net Conductance, Ph-Sensitivity, And Functional Integrity Of A Novel Truncate Of The M2 Ion "Channel" Of Influenza A, Emily Peterson Nov 2010

Proteoliposome Proton Flux Assays Establish Net Conductance, Ph-Sensitivity, And Functional Integrity Of A Novel Truncate Of The M2 Ion "Channel" Of Influenza A, Emily Peterson

Theses and Dissertations

A novel truncate of Influenza A M2 protein (residues 22-62), incorporated into a uniquely tailored proteoliposome proton uptake assay, demonstrated proton flux more characteristic of an ion transporter than a traditional ion "channel." The liposome paradigm was essential for testing the conductance activity of this M2 truncate at a range of extraphysiological pHs appropriate for channel vs. transport function determination. In addition to transporter-typical proton flux, M2(22-62) showed the key characteristics of functional integrity: selective proton uptake into liposomes and block of uptake by amantadine. Two sets of proteoliposome proton flux assays were carried out, Set 1 at pH values …


Characterization Of The Lkb1-Mo25-Strad Ampkk Complex In Adult Mouse Skeletal Muscle, Cody Don Smith Nov 2010

Characterization Of The Lkb1-Mo25-Strad Ampkk Complex In Adult Mouse Skeletal Muscle, Cody Don Smith

Theses and Dissertations

In liver tissue, the AMP-activated protein kinase kinase (AMPKK) complex was identified as the association of LKB1, MO25α/β, and STRADα/β proteins; however, this complex has yet to be characterized in skeletal muscle. In this report, we demonstrate the expression of the LKB1-MO25-STRAD AMPKK complex in adult skeletal muscle, confirm the absence of mRNA splice variants, and report the relative mRNA expression levels of these complex-forming proteins. To facilitate this characterization we used control (ctrl) and muscle-specific LKB1 knockout (LKB1-/-) mice. LKB1 detection in untreated ctrl and LKB1-/- muscle lysates revealed two protein bands at approximately 50 and 60 kDa; although, …


Work Towards The Isolation And Characterization Of The Muscle Isoform Of Glucose 1,6-Bisphosphatase, Caleb J. Hiller Nov 2010

Work Towards The Isolation And Characterization Of The Muscle Isoform Of Glucose 1,6-Bisphosphatase, Caleb J. Hiller

Theses and Dissertations

Glucose 1,6-bisphosphate is an important small molecule involved in the regulation of glycolysis. Four enzymes synthesize this compound. One enzyme is known to degrade it, glucose 1,6-bisphosphatase. Other groups have produced work that indicates that there are two isoforms of this enzyme, one predominant in the brain and one in the muscle. This thesis contains the work performed in attempts to isolate and characterize the muscle isoform of glucose 1,6-bisphosphatase. While this enzyme was not isolated, much was learned about it and the results from this work may help in the future identification of this enzyme.


Effects Of Diabetic State And Gender On Pro-Inflammatory Cytokine Secretion By Human Macrophages Infected With Burkholderia Pseudomallei, Annette J. Blam Nov 2010

Effects Of Diabetic State And Gender On Pro-Inflammatory Cytokine Secretion By Human Macrophages Infected With Burkholderia Pseudomallei, Annette J. Blam

Theses and Dissertations

Burkholderia pseudomallei is a gram-negative opportunistic soil pathogen that causes the life-threatening disease melioidosis. It is endemic in Northern Australia and Southeast Asia but can be found throughout many other regions in the world. Diabetes mellitus is a predisposing risk factor for infection with this organism and it has been demonstrated that diabetic males are particularly susceptible to severe infection. Previous research suggested that monocytes isolated from the whole blood of diabetic males demonstrated a decreased ability to produce the proinflammatory cytokines IL-1β and IL-8. We hypothesized that monocyte-derived macrophages from diabetic males would also secrete lower levels of pro-inflammatory …


Electromyographic Analysis Of The Infraspinatus And Deltoid Muscles During Shoulder External Rotation Exercises With And Without A Towel Roll, Kazuto Sakita Nov 2010

Electromyographic Analysis Of The Infraspinatus And Deltoid Muscles During Shoulder External Rotation Exercises With And Without A Towel Roll, Kazuto Sakita

Theses and Dissertations

Standing and sidelying external rotation exercises produce high activation of the deltoid and infraspinatus. Holding a towel roll under the arm at 30° shoulder abduction during these exercises may decrease deltoid activity and increase infraspinatus activity. The objective was to determine if the addition of a towel under the arm during standing and sidelying external rotation affects EMG activity of the infraspinatus, middle and posterior deltoid, and pectoralis major, compared to the no towel condition. 20 male volunteers (age; 26 ± 3, height; 1.80 m ± .07 m, weight; 77 kg ± 10 kg) had right dominant hand, bilaterally healthy …


Accelerated Shelf Life Determination Of Antioxidant Stabilized High Oleic Sunflower And Canola Oils In Plastic Bottles, Christine Nicole Shearer Nov 2010

Accelerated Shelf Life Determination Of Antioxidant Stabilized High Oleic Sunflower And Canola Oils In Plastic Bottles, Christine Nicole Shearer

Theses and Dissertations

Vegetable oil is an important commodity; however, the majority of commercially available vegetable oils have a fairly short shelf life, which limits their usefulness for long term food storage, disaster relief, space travel, food aid programs, and military rations. Vegetable oils with high oleic acid and reduced linolenic acid contents, especially with added antioxidant combinations, were previously found to have significantly longer oil stability index (OSI) values than traditional vegetable oils. This study used accelerated shelf life testing to estimate the ambient shelf life of high oleic sunflower oil (HOSUN) and high oleic canola oil (HOCAN), each containing 1,000 ppm …


Kinematic Changes Of The Tennis Forehand Ground Stroke As Post Contact Ball Speed Increases, Merrill D. Funk Nov 2010

Kinematic Changes Of The Tennis Forehand Ground Stroke As Post Contact Ball Speed Increases, Merrill D. Funk

Theses and Dissertations

Neuromuscular and kinematic patterns during the tennis forehand have been studied extensively. However, no one has evaluated potential upper-extremity kinematic changes during the forehand as ball speed increases. The purpose of this study was to evaluate changes in shoulder and trunk kinematics as forehand ball speed increased, in an attempt to better understand how kinematics may promote forehand ball speed. Peak trunk rotation angle, shoulder horizontal abduction/adduction and internal/external rotation angle, and corresponding angular velocities were measured between initial backswing and ball contact during forehands that were performed at three different speeds (50%, 75%, and 100% of maximal post-impact ball …


Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang Nov 2010

Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang

Theses and Dissertations

New ion trap mass spectrometry (ITMS) instrumentation, the toroidal IT and halo IT, were developed to meet the significant growth in on-site analysis applications. The miniature toroidal IT mass analyzer was operated with radio frequency (RF) trapping voltages of 3 kVp-p or less. Despite its reduced dimensions, it has roughly the same ion trapping capacity as conventional 3D quadrupole ITs. Unit-mass resolved spectra for n-butylbenzene, xenon, and naphthalene were obtained. The desired linear mass scale was obtained using conventional mass-selective instability scan combined with resonance ejection. The halo IT was also based on toroidal trapping geometry and microfabrication technology, consisting …


Can Grain Be Disinfested In 5-Gal Hdpe Buckets Containing Oxygen Absorber Packets?, Lynn V. Ogden, C. Griffin Oct 2010

Can Grain Be Disinfested In 5-Gal Hdpe Buckets Containing Oxygen Absorber Packets?, Lynn V. Ogden, C. Griffin

Faculty Publications

Effective methods of grain disinfestation include freezing, the use of carbon dioxide gas, and the use of pesticides. Oxygen deprivation has also been shown to be an effective method of disinfestation when the oxygen content is held below 1% for at least 12 days (d). High Density Polyethylene (HDPE) 5 gallon (gal) buckets have become a popular and convenient storage container for dry foods such as wheat, rice and beans. Oxygen absorber packets are an effective way to remove the oxygen in high-barrier sealed containers to prolong the life of many of these foods. It is hypothesized that sealed HDPE …


Feasibility Of Re-Using Pete Soda Bottles To Exclude Oxygen During Storage Of Low Moisture Foods, Sarah Broderick, Michelle A. Lloyd, Lynn V. Ogden, Oscar A. Pike Oct 2010

Feasibility Of Re-Using Pete Soda Bottles To Exclude Oxygen During Storage Of Low Moisture Foods, Sarah Broderick, Michelle A. Lloyd, Lynn V. Ogden, Oscar A. Pike

Faculty Publications

Many consumers are beginning to store grain on their own creating a need for easy disinfestation methods that can be accomplished in the home. Oxygen deprivation has proven to be an effective method for grain disinfestation when kept below 1% for 12 days. Re-using PETE soda bottles is an easy way many consumers can store their grains. The purpose of this study was to determine if using oxygen absorber packets in used PETE soda bottles will keep the oxygen percent low enough to disinfest the grain stored in them. Experiments were carried out to determine how long oxygen absorber packets …


Functionalization Of Diamond And Its Application In High Performance Liquid Chromatography And Solid Phase Extraction, Gaurav Saini Oct 2010

Functionalization Of Diamond And Its Application In High Performance Liquid Chromatography And Solid Phase Extraction, Gaurav Saini

Theses and Dissertations

The primary focus of my work was to chemically functionalize diamond as normal and reversed phases for solid phase extraction (SPE) and high performance liquid chromatography (HPLC). Diamond was functionalized with -NH2 groups via self-limiting adsorption of an amine-containing polymer, polyallylamine (PAAm), onto oxidized diamond particles. The chemical stability of these particles was improved by thermal curing or chemical crosslinking with 1,2,5,6-diepoxycyclooctane. The reversed phase material for SPE was synthesized by reacting amine-functionalized diamond particles with long chain alkyl and a perfluorinated isocyanate. Unlike commercially available silica, functionalized diamond particles were stable under extreme pH conditions (pH 0-14). Functionalized diamond …


Axial Temperature Gradients In Gas Chromatography, Jesse Alberto Contreras Sep 2010

Axial Temperature Gradients In Gas Chromatography, Jesse Alberto Contreras

Theses and Dissertations

The easiest and most effective way to influence the separation process in gas chromatography (GC) is achieved by controlling the temperature of the chromatographic column. In conventional GC, the temperature along the length of the column is constant at any given time, T(t). In my research, I investigated the effects of temperature gradients on GC separations as a function of time and position, T(t,x), along the column. This separation mode is called thermal gradient GC (TGGC). The research reported in this dissertation highlights the fundamental principles of axial temperature gradients and the separation potential of the TGGC technique. These goals …


Predicting The Distribution Of Air Pollution Sensitive Lichens Using Habitat Niche Modeling, Gajendra Shrestha Aug 2010

Predicting The Distribution Of Air Pollution Sensitive Lichens Using Habitat Niche Modeling, Gajendra Shrestha

Theses and Dissertations

Usnea hirta and Xanthoparmelia cumberlandia are commonly used as bio-monitors of air quality. In order to more accurately and efficiently determine the distribution of these two sensitive indicator species, we have developed a probabilistic distribution map as a function of 9 macroclimatic and topographic variables for the White River National Forest, Colorado using Non-Parametric Multiplicative Regression (NPMR) analysis. Furthermore, we also developed a logistic regression (LR) model for X. cumberlandia in order to evaluate the strengths and limitations of the NPMR model. The best model for U. hirta included four variables - solar radiation, average monthly precipitation, average monthly minimum …


Integrated Affinity Column Capillary Electrophoresis Microdevices For Biomarker Analysis, Weichun Yang Aug 2010

Integrated Affinity Column Capillary Electrophoresis Microdevices For Biomarker Analysis, Weichun Yang

Theses and Dissertations

In this dissertation, microfluidic systems that integrate antibody-based sample preparation methods with electrophoretic separation are developed to analyze multiple biomarkers in a point-of-care setting. To form an affinity column, both monolith materials and wall-coated channels were explored. I successfully demonstrated that monolith columns can be prepared in microfluidic devices via photopolymerization. The selectivity of monolith columns was improved by immobilizing antibodies on the surface. These affinity columns can selectively enrich target analytes and reduce the signal of contaminant proteins up to 25,000 fold after immunoaffinity extraction. These results clearly demonstrate that microchip affinity monoliths can selectively concentrate and purify target …


Synthesis And Characterization Of An Oligothiophene-Ruthenium Complex And Synthesis And Optical Properties Of Oligothiophene-Ruthenium Complexes Bound To Cdse Nanoparticles, Nathan A. Bair Aug 2010

Synthesis And Characterization Of An Oligothiophene-Ruthenium Complex And Synthesis And Optical Properties Of Oligothiophene-Ruthenium Complexes Bound To Cdse Nanoparticles, Nathan A. Bair

Theses and Dissertations

Oligothiophenes are of increasing interest in organic based electronic devices in part due to their high electron and hole mobilities. In an organic photovoltaic (OPV) device, the electronic properties of oligothiophenes make them advantageous as charge transfer junctions. To serve as charge transfer junctions, oligothiophenes must be functionalized to bind to the donor and acceptor parts of the device. The donor and acceptor parts are different materials and the synthesis of asymmetric oligothiophenes is of great interest. Previous researchers in our lab synthesized four asymmetric oligothiophenes, two with two thiophene subunits and two with four. Each set of oligothiophenes contained …


The Effects Of Resistance Training On Strength And Body Composition In Postpartum Women, Katherine Bishop Pratt Aug 2010

The Effects Of Resistance Training On Strength And Body Composition In Postpartum Women, Katherine Bishop Pratt

Theses and Dissertations

The postpartum period represents a high-risk period for body weight retention and obesity. Several studies have investigated the role of aerobic exercise on postpartum weight retention and other body composition outcomes; however, there has been little attention given to resistance training in postpartum women. Thus, the purpose of this four-month randomized study was to determine the effectiveness of resistance training on strength, body composition, return to pre-pregnancy weight, and bone mineral density (BMD) in postpartum women. Sixty postpartum women were randomly assigned to either a resistance training group or a comparison group. The resistance training group participated in a progressive …


Role Of Ampk In The Upregulation Of Steroidogenic Acute Regulatory Protein In The Zona Fasciculata Of The Adrenal Cortex, Adam Wesley Dayton Aug 2010

Role Of Ampk In The Upregulation Of Steroidogenic Acute Regulatory Protein In The Zona Fasciculata Of The Adrenal Cortex, Adam Wesley Dayton

Theses and Dissertations

Cortisol is a glucocorticoid produced by the zona fasciculata (ZF) of the adrenal cortex. Traditionally, cortisol production and release was seen as being regulated strictly by adrenocorticotropic hormone (ACTH). While this is true of baseline cortisol levels and in response to acute mental stress, the picture is somewhat more complicated in other situations.Interleukin-6 (IL-6) contributes to the maintenance of cortisol levels in situations of prolonged immune or inflammatory stress. AMP activated protein kinase (AMPK) was investigated as a possible mediator of the action of IL-6 or as an independent actor in raising cortisol levels in response to hypoxemic or hypoglycemic …


Beta Galactosidose Activity Of Commercial Lactase Samples In Raw And Pasteurized Milk At Refrigerated Temperatures, Trenton W. Horner Aug 2010

Beta Galactosidose Activity Of Commercial Lactase Samples In Raw And Pasteurized Milk At Refrigerated Temperatures, Trenton W. Horner

Theses and Dissertations

Many consumers are unable to enjoy the benefits of milk, due to lactose-intolerance. Lactose-free milk is available, but at about 2 times the cost of regular milk or greater, it may be difficult for consumers to afford. The high cost of lactose-free milk is in part due to the added cost of the lactose hydrolysis process. Hydrolysis at refrigerated temperatures, possibly in the bulk tank or package, could increase the flexibility of the process, and potentially reduce the cost. A rapid β-galactosidase assay was used to determine the relative activity of commercially available lactase samples at different temperatures. Four enzymes …