Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Theses and Dissertations

Discipline
Institution
Keyword
Publication Year
File Type

Articles 14701 - 14730 of 19641

Full-Text Articles in Entire DC Network

Effects Of River Discharge And Marine Environmental Factors On The Brown Shrimp Fishery In The Northern Gulf Of Mexico, Adam George Pollack Dec 2009

Effects Of River Discharge And Marine Environmental Factors On The Brown Shrimp Fishery In The Northern Gulf Of Mexico, Adam George Pollack

Theses and Dissertations

Regression analyses and delta-lognormal models were used to investigate whether river discharge and environmental variables significantly affected relative abundance of brown shrimp, Farfantepenaeus aztecus, in the northern Gulf of Mexico. Significant negative relationships were found between mean river flow during winter and spring months and catch rates (CPUE) off Texas, Louisiana and Mississippi/Alabama. However, during the same months significant positive relationships between CPUE and the variation in mean river discharge were found for each state. In Texas and Louisiana, delta-lognormal models revealed depth zone was the most significant variable (P≤0.001) in describing distribution, while time of day (P≤0.001) was most …

Go to article

Effects Of Various Fumigants And Alternative Processing Methods On The Safety, Volatile Composition, And Sensory Quality Of Dry Cured Ham, Ramandeep Kaur Sekhon Dec 2009

Effects Of Various Fumigants And Alternative Processing Methods On The Safety, Volatile Composition, And Sensory Quality Of Dry Cured Ham, Ramandeep Kaur Sekhon

Theses and Dissertations

Randomized complete block designs with three replications were utilized to evaluate the effects of fumigation with sulfuryl fluoride (SF) (0, 12, 24, 36 and 72 mg/L), phosphine (PH3) (0, 200 and 1000 ppm at 48 hr), methyl bromide (MB) (0, 4, 8, 16, and 32 mg/L for 48 hr), carbon dioxide (CO2) (0, 60% at 48 hr and 60% at 96 hr) and ozone (O3) (0 ppm and 175 ppm for 48 hr) on the volatile flavor compound concentrations in dry cured ham. Fluoride and SF concentrations increased (P < 0.05) in dry cured hams as SF fumigation concentration increased, but all samples contained fluoride and SF concentrations below the legal limits of 20 and 0.01 ppm, respectively. Also, as phosphine fumigation concentration increased, the residual concentration of phosphine also increased in the hams (P < 0.05), but all samples contained levels that were lower than the legal limit of phosphine in stored food products (0.01 ppm). Minimal differences existed in the presence and concentration of aroma active compounds in fumigated hams when compared to the control. Triangle tests indicated that consumers could not discern (P > 0.75) between the control hams and the fumigated hams. This study …

Go to article

Efforts Toward Understanding Dietary Components And The Reproductive Behaviors And Limitations Of The Giant Panda (Ailuropoda Melanoleuca), Erin Donivan Trueblood Dec 2009

Efforts Toward Understanding Dietary Components And The Reproductive Behaviors And Limitations Of The Giant Panda (Ailuropoda Melanoleuca), Erin Donivan Trueblood

Theses and Dissertations

Preservation of giant pandas, Ailuropoda melanoleuca, is a worldwide concern. This study was designed to examine dietary and reproductive challenges associated with panda management. Phytoestrogens are natural plant compounds that mimic estrogen and often negatively impact mammalian reproduction. Phytoestrogens in bamboo, the panda’s primary food source, is unknown. Here, estrogen radioimmuno- and receptor-binding assays revealed estrogenic activity in three species of Phyllostachys bamboo. These results present indirect evidence of phytoestrogenic mimics in bamboo, but their relevance is still unknown. Studies were also conducted to observe panda reproductive behaviors in an attempt to augment the use of an artificial vagina (AV) …

Go to article

Crosstalk Between Angiotensin Ii Receptors And Insulin Receptor: A Possible Mechanism For The Co-Development Of Hypertension And Insulin Resistance, Maya Ramdas Dec 2009

Crosstalk Between Angiotensin Ii Receptors And Insulin Receptor: A Possible Mechanism For The Co-Development Of Hypertension And Insulin Resistance, Maya Ramdas

Theses and Dissertations

Molecular analysis of the cross talk between Angiotensin II (Ang II) and insulin signaling systems reveal that they are multifaceted and occur at cellular level and intracellular level. Experiments were carried out to evaluate the crosstalk between the Ang II receptors-AT1 and AT2 and the Insulin Receptor (IR) to understand the changes in the signaling pathway that could lead to the transition from hypertension to insulin resistance. Transient expression of rat AT2 in CHO cells induced co-immunoprecipitation of the AT2R with IRâ and inhibition of IRâ tyrosine phosphorylation. An AT2-peptide carrying the amino acids 226-363 (that spans 3rd intracellular loop …

Go to article

Biomass Pretreatment For Increased Anhydrosugars Yield During Fast Pyrolysis, Qi Li Dec 2009

Biomass Pretreatment For Increased Anhydrosugars Yield During Fast Pyrolysis, Qi Li

Theses and Dissertations

Production of liquid fuels is a high national priority to provide transporation fuels. Production of liquid biouels from biomass has been idenfied as a viable goal over the next decades. Fast pyrolysis is the rapid thermal degradation of lignocellulosic biomass in the absence of oxygen. Levoglucosan, which can be hydrolyzed and fermented into bio-ethanol, is produced during the pyrolysis process of the cellulose contained in biomass. Pure cellulose results in the production of levoglucosan of more than 50% by feedstock weight while woody biomass typically produces about 3% during pyrolysis. Researchers have performed significant research into methods to increase yields …

Go to article

Laser Induced Incandescence And Laser Induced Breakdown Spectroscopy Based Sensor Development, Kemal Efe Eseller Dec 2009

Laser Induced Incandescence And Laser Induced Breakdown Spectroscopy Based Sensor Development, Kemal Efe Eseller

Theses and Dissertations

In this doctoral dissertation, two laser-based sensors were evaluated for different applications. Laser Induced Incandescence (LII) is a technique which can provide nonintrusive quantitative measurement of soot and it provides a unique diagnostic tool to characterize engine performance. Since LII is linearly proportional to the soot volume fraction, it can provide in situ, real time measurement of soot volume fraction with high temporal and spatial resolution. LII has the capability to characterize soot formation during combustion. The soot volume fraction from both flames and a soot generator was investigated with LII. The effects of experimental parameters, such as laser fluence, …

Go to article

Faunal Communities Of Temporary Wetlands Of Upland And Floodplain Public Forested Lands In North Mississippi, Katherine E. Edwards Dec 2009

Faunal Communities Of Temporary Wetlands Of Upland And Floodplain Public Forested Lands In North Mississippi, Katherine E. Edwards

Theses and Dissertations

I conducted surveys of amphibian, reptile, and small mammal communities surrounding 4 isolated, upland and 6 stream-connected temporary wetlands on Tombigbee National Forest and Noxubee National Wildlife Refuge in north Mississippi from May 2001 - March 2006. Trap captures yielded 17 amphibian species (n = 11,142), 21 reptile species (n = 541), and 10 small mammal species (n = 472). Upland pools supported greater diversity of Ambystomatid salamanders, anurans, lizards, and mice (Peromyscus spp.), than floodplain pools. Factors including landscape position of pools, proximity to alternate water sources, and barriers to dispersal potentially influenced faunal communities of temporary wetlands. Infrared-triggered …

Go to article

Nutrient Management In On-Site Wastewater Treatment, Ayanangshu Dey Dec 2009

Nutrient Management In On-Site Wastewater Treatment, Ayanangshu Dey

Theses and Dissertations

Groundwater and surface water contamination has been linked in the past to inadequate or failing on-site wastewater treatment and disposal systems. The on-site wastewater systems installed in coastal areas have more potential for inflicting this kind of environmental damage. This work studied the regulatory compliance and environmental protection of the four types of on-site wastewater disposal systems found on the Mississippi Gulf Coast; i.e., vegetative rock filter, subsurface drip irrigation, sand mound, and sprinkler systems, by statistical techniques. Compliance was also evaluated for groundwater samples collected from monitoring wells installed at four corners of a disposal field. This work eventually …

Go to article

Obstacle Array Drag Coefficient Parametric Response Surface Analysis, Mouthgalya Ganapathy Dec 2009

Obstacle Array Drag Coefficient Parametric Response Surface Analysis, Mouthgalya Ganapathy

Theses and Dissertations

Throughout literature, one finds where numerous methodologies and models have been developed to predict the effect of surface roughness on a flat surface. Many of the models utilize a drag coefficient as one of the necessary parameters. In urban settings with groups of buildings, the drag coefficient on an individual obstacle would be determined by parameters like wind direction and the relative positioning of a building, in addition to Reynolds number and shape. Computational experiments were performed to simulate the fluid flow around a single row and two rows of “cube” obstacles. Based on dimensional analysis, the drag coefficient was …

Go to article

Rapid Identification Of Aspergillus Spp. Using A Pcr Based Melting Curve Method And Characterization Of A Novel Chitinase In Insect Resistant Maize Lines, Biing-Ru Wu Dec 2009

Rapid Identification Of Aspergillus Spp. Using A Pcr Based Melting Curve Method And Characterization Of A Novel Chitinase In Insect Resistant Maize Lines, Biing-Ru Wu

Theses and Dissertations

Identification of fungal isolates is critical in studying Aspergillus flavus ecology and for developing methods to reduce aflatoxin contamination. In our efforts to track biocontrol applications of the atoxigenic A. flavus K49 (NRRL 30797), we have developed a rapid and accurate classification system for A. flavus based on PCR product melting temperatures (Tm). Using 18 primers and a total of 59 Aspergilli strains, including all 49 representatives of the Georgian peanut Vegetative Compatibility Groups (VCGs), a decision tree Tm flowchart was generated. The decision tree can classify all 59 strains using only 9 of the SSR primers and an average …

Go to article

Pathogen Entrance And Development Of Disease During Infection Of The American Channel Catfish Ictalurus Punctatus By The Enterobacterium Edwardsiella Ictaluri, Simon Menanteau-Ledouble Dec 2009

Pathogen Entrance And Development Of Disease During Infection Of The American Channel Catfish Ictalurus Punctatus By The Enterobacterium Edwardsiella Ictaluri, Simon Menanteau-Ledouble

Theses and Dissertations

Since being first reported in the late 1980ies, the Enterobacterium Edwardsiella ictaluri has rose in prevalence to become one of the two most damaging pathogens affecting the channel catfish industry. Despite this significance of the pathogen, understanding of the development of the disease, especially its route of entry into the host and the earlier stages of the infection, is still incomplete. A series of challenges were conducted using bioluminescent E. ictaluri either by infecting fish through immersion or topical application of the bacteria directly on the intact or abraded epithelium. This showed that abraded fish developed septicemia and died faster …

Go to article

Optimization Of The Production Of The Lantibiotics Mutacin 1140 In Modified M9 Media, Neeti Dahal Dec 2009

Optimization Of The Production Of The Lantibiotics Mutacin 1140 In Modified M9 Media, Neeti Dahal

Theses and Dissertations

Mutacin 1140, a class 1 bacteriocin, is produced by Streptococcus mutans and belongs to the type A lantibiotic family. Experiments were done to optimize production of mutacin 1140 in minimal media enabling a more cost efficient downstream purification method. The development of a small volume fermentation method enabled a rapid screen of several variables in a standard shaking incubator. This method provided a fast approach for determining components that promote mutacin 1140 production in minimal media broth. Lactose was determined to be the optimal carbon source for mutacin 1140 production. High concentrations of CaCl2 (0.3% w/v) and MgSO4 (0.77% w/v) …

Go to article

Identification Of Micrornas In Bovine Spermatozoa With Implications Of Fertility, Lashonda S (Lashonda Shakita) Robertson Dec 2009

Identification Of Micrornas In Bovine Spermatozoa With Implications Of Fertility, Lashonda S (Lashonda Shakita) Robertson

Theses and Dissertations

MicroRNAs are small RNA molecules that could possibly play a major role in fertility. In the experiment, spermatozoa were extracted from bovine followed by an extraction of total RNA. Bovine spermatozoa were extracted from two bulls of different fertility, high and low fertility. An expression array was done to compare the expression levels of the microRNAs. It was shown that thousands of microRNAs are present in bovine spermatozoa but only a small amount was significantly expressed. The microRNAs from low fertility bulls were more highly expressed than those in high fertility bulls. A Bioanalyzer gel was used to confirm the …

Go to article

Improving Structural And Functional Annotation Of The Chicken Genome, Teresia Buza Dec 2009

Improving Structural And Functional Annotation Of The Chicken Genome, Teresia Buza

Theses and Dissertations

Chicken is an important non-mammalian vertebrate model organism for biomedical research, especially for vaccine production and the study of embryology and development. Chicken is also an important agricultural species and major food source for high-quality protein worldwide. In addition, chicken is an important model organism for comparative and evolution genomics. Exploitation of this genome as a biomedical model is hindered by its incomplete structural and functional annotation. This incomplete annotation makes it difficult for researchers to model their functional genomics datasets. Improving structural and functional annotation of the chicken genome will allow researchers to derive biological meaning from their functional …

Go to article

In Vivo And In Vitro Nutrient Balance And Assessment Of Pcr And Biophotonics As Techniques For Evaluating Ruminal Bacteria, Adam I. Orr Dec 2009

In Vivo And In Vitro Nutrient Balance And Assessment Of Pcr And Biophotonics As Techniques For Evaluating Ruminal Bacteria, Adam I. Orr

Theses and Dissertations

To better understand the facets of nutrient utilization, a series of in vivo and in vitro studies were undertaken to elucidate the effect of supplementation on utilization of moderate-quality bermudagrass hay and to identify mechanisms to evaluate the role of rumen bacterial populations on feedstuff utilization. A digestion trial was conducted using 6 ruminally cannulated steers receiving bermudagrass hay supplemented with soybean hulls (HULLS), cracked corn (CORN), or soybean hulls and cracked corn (MIX; 75% and 25%, respectively) in a 3x3 Latin Rectangle arrangement. Additionally, ruminal fluid was continuously cultured using the BioFlo® 110 fermentation system to evaluate the in …

Go to article

Inhibition Of Human Carboxylesterases: Exploring Interindividual Variation Of Biochemical Activity And Novels Physiological Functions Of Carboxylesterases, Shuqi Xie Dec 2009

Inhibition Of Human Carboxylesterases: Exploring Interindividual Variation Of Biochemical Activity And Novels Physiological Functions Of Carboxylesterases, Shuqi Xie

Theses and Dissertations

Carboxylesterases (CEs) are nonspecific hydrolytic enzymes and responsible for the metabolism of xenobiotics and endobiotics that contain ester bonds. There are two human CE isoforms found in liver, CES1 and CES2. In this study it is shown that the mere abundance of CES1 protein expression in human liver does not predict its biochemical activity. The human interindividual variation in CES1 activities may attribute to several mechanisms. One possibility is the presence of endogenous inhibitors in liver, arachidonic acid (AA) and 27-hydroxycholesterol (27-HC). CES1 is also expressed in human monocytes/macrophages and is proposed to catalyze the rate-limiting step of cholesterol ester …

Go to article

Advancements In Power System Monitoring And Inter-Operability, Vinoth Mohan Mohan Dec 2009

Advancements In Power System Monitoring And Inter-Operability, Vinoth Mohan Mohan

Theses and Dissertations

In a typical utility control center, there could be hundreds of applications running to take care of day-to-day functionality. In many cases, these applications are custom-built by different vendors. With the expectation for high reliability of the electric power grid, many utilities are increasingly moving towards sharing data with each other and with security coordinators. But this data exchange is hampered by incompatible electrical applications built on proprietary data formats and file systems. Electric Power Research Institute's (EPRI‟s) Common Information Model (CIM) was envisioned as a one-sizeits-all data model to remove incompatibility between applications. This research work utilizes the CIM …

Go to article

An Assessment Of Reading Programs In North Mississippi Elementary Schools: A Comparative Analysis, Angela Delentheia Bluitt Dec 2009

An Assessment Of Reading Programs In North Mississippi Elementary Schools: A Comparative Analysis, Angela Delentheia Bluitt

Theses and Dissertations

The purpose of this study was to compare the impact of reading programs of students who used the Reading Program One, Reading Program Two, and Reading Program Three reading programs and those students who were taught using no basal reading program in North Mississippi. The study also assessed teachers’ perceptions of the various reading programs based on gender, age, educational attainment, and years of teaching experience. The research design for this study included a descriptive analysis. Ten elementary schools in North Mississippi using the Reading Program One, Reading Program Two, Reading Program Three, and no basal reading program were analyzed. …

Go to article

An Examination Of Crisis Preparedness At Christian-Affiliated Institutions Of Higher Education, Stacy M. Burrell Dec 2009

An Examination Of Crisis Preparedness At Christian-Affiliated Institutions Of Higher Education, Stacy M. Burrell

Theses and Dissertations

The purpose of this study was to examine crisis preparedness at Christian-affiliated institutions of higher education. Second, this study examined Christian-affiliated institutions of higher education presidents’ perspective of their institution’s ability to prepare for crises based upon the four critical indicators of organizational crisis preparedness as described by Zdziarski (2001): a) the types of crisis institutions prepare for, b) the phase of crisis prepared for, c) the systems in place to respond to crisis, and d) the stakeholders involved and considered in preparations. Implications from this study provided recommendations for crisis preparedness that are specific to Christian-affiliated colleges and universities. …

Go to article

Molecular And Biochemical Role Of Auxin And Cytokinin In Dedifferentiation And Organogenesis Of Arabidopsis, Aparna Kakani Dec 2009

Molecular And Biochemical Role Of Auxin And Cytokinin In Dedifferentiation And Organogenesis Of Arabidopsis, Aparna Kakani

Theses and Dissertations

Cell dedifferentiation is a cell fate regression process in which the cell fate memory of a differentiated cell is erased, leading to regain stem cell characteristics. Auxin regulates both cell dedifferentiation and differentiation in plants. It is unknown how auxin controls the two opposite processes. Here the minimal auxin requirements for cell dedifferentiation were found, molecular markers associated with the cell dedifferentiation event were identified. When cellular auxin concentration exceeds the level of meristem cell, most differentiated cells undergo dedifferentiation. In differentiated cells, the polar auxin efflux system prevents cell dedifferentiation by reducing auxin accumulation, particularly in the presence of …

Go to article

Movements, Relatedness And Modeled Genetic Manipulation Of White-Tailed Deer, Stephen Lance Webb Dec 2009

Movements, Relatedness And Modeled Genetic Manipulation Of White-Tailed Deer, Stephen Lance Webb

Theses and Dissertations

White-tailed deer (Odocoileus virginianus) have been intensively studied across their range. However, many aspects of the white-tailed deer’s ecology have not been studied or are difficult to study. The advent of global positioning system (GPS) collar technology and molecular genetics techniques now allows researchers to collect fine-scale and cryptic phenomena. In addition, selective harvest of male white-tailed deer, based on antler size, has not been critically evaluated. Thus, development and use of quantitative genetics models will be useful for elucidating the effects of selective harvest on mean population antler size. I used GPS collar technology to further understand white-tailed deer …

Go to article

Multidisciplinary Evaluation Of No-Till Corn Grazing Systems In Mississippi, Dawn Holland Manning Dec 2009

Multidisciplinary Evaluation Of No-Till Corn Grazing Systems In Mississippi, Dawn Holland Manning

Theses and Dissertations

To ascertain potential ecological and landowner benefits of non-conventional agricultural systems, this project was designed to monitor cattle production and mourning dove (Zenaida macroura) utilization of land areas that allowed grazing cattle to harvest corn planted with no-till methods. In 2005-2008, study sites were located in four counties of MS, including four steer/heifer-grazed and harvested corn fields (SHS) and four conventionally-managed and combine-harvested corn fields (CHS). Vegetation characteristics, residual grain quantities, and use by doves were measured on SHS and CHS. Steer average daily gains (ADG), quality grades, and feedlot days were compared to traditional cattle production methods. Mourning dove …

Go to article

The Role Of Cattle And Gulf Coast Ticks (Amblyomma Maculatum) In The Epidemiology Of Rickettsia Parkeri Infection, Kristine T. Edwards Dec 2009

The Role Of Cattle And Gulf Coast Ticks (Amblyomma Maculatum) In The Epidemiology Of Rickettsia Parkeri Infection, Kristine T. Edwards

Theses and Dissertations

I hypothesized cattle and Gulf Coast ticks (GCT), Amblyomma maculatum, may be involved in epidemiology of Rickettsia parkeri infection. I demonstrated transient rickettsemia by polymerase chain reaction (PCR) for the 17 kilodalton (kDa) gene in 33% (2/6) of calves experimentally exposed to R. parkeri either by direct inoculation or by placement of R. parkeri-infected GCT on calves’ ears. Calves (4/4) receiving GCT developed lesions at attachment sites consistent with a pathologic condition known as “gotch” ear whether or not GCT were infected with R. parkeri, suggesting the condition is related to GCT attachment and not to rickettsial infection. In calves …

Go to article

Visual Perception And Gestalt Grouping In The Landscape: Are Gestalt Grouping Principles Reliable Indicators Of Visual Preference?, Mark Reinhardt Levy Dec 2009

Visual Perception And Gestalt Grouping In The Landscape: Are Gestalt Grouping Principles Reliable Indicators Of Visual Preference?, Mark Reinhardt Levy

Theses and Dissertations

Landscape visual preference research has indicated many potential indicators of preference; however a comprehensive framework concerning the relationship between visual preference and perception has not been solidified. Gestalt psychology, the predecessor to visual perception, proposes certain visual grouping tendencies to explain how humans perceive the world. This study examines if Gestalt grouping principles are reliable indicators of preference, and if they may be used to develop a broad context for visual assessment. Visual preference for 36 landscape scenes testing the proximity and similarity of landscape elements were ranked one through five by 1,749 Mississippi State University undergraduate, graduate, and faculty …

Go to article

Flow Structure/Particle Interaction In The Small Bronchial Tubes, Belabahen Soni Dec 2009

Flow Structure/Particle Interaction In The Small Bronchial Tubes, Belabahen Soni

Theses and Dissertations

The laminar flow in the small bronchial tubes is quite complex due to the presence of vortex-dominated, secondary flows. Contributing to this complexity are the geometrical characteristics of the bronchial tubes that include asymmetric and nonplanar branching. These secondary flow fields play a crucial role in particle deposition; however, the actual mechanisms that determine the particle distributions are not fully understood. The research reported here increases understanding of this phenomenon by studying flow structure/ particle interaction in the small bronchial tubes for steady and unsteady respiratory conditions. Specifically, the effects of simultaneous nonplanar and asymmetric branching were investigated. The nonplanar …

Go to article

Flower Forcing In Banana Shrub (Michelia Skinneriana Dunn.) And Bougainvillea (Bougainvillea Wild.), Shen Ma Dec 2009

Flower Forcing In Banana Shrub (Michelia Skinneriana Dunn.) And Bougainvillea (Bougainvillea Wild.), Shen Ma

Theses and Dissertations

Flower forcing to meet holiday market can increase the value of potted flowering plants. This study was to investigate the effects of chilling and post-chilling photoperiod treatments on flowering of banana shrub and the effects of water stress, daminozide, chlormequat, and ethephon on flowering of bougainvillea. Experiments were conducted at R.R. Foil Plant Science Research Center and MSU Dorman Greenhouse at Mississippi State University (MSU), Mississippi State, MS. Results from banana shrub experiment indicated that 8-week chilling at 8 ºC was necessary for banana shrub to break bud dormancy and a tank mix of daminozide and chlormequat was able to …

Go to article

Fractionation Of Soybean Meal, Cottonseed Meal And Wheat Middlings Using Combination Of Sieving And Air Classification, Ravi Kumar Challa Dec 2009

Fractionation Of Soybean Meal, Cottonseed Meal And Wheat Middlings Using Combination Of Sieving And Air Classification, Ravi Kumar Challa

Theses and Dissertations

Fiber separation from these animal feeds could increase the protein and hence increase the value of the animal feed. The objective of the study was to evaluate the combination of sieving and air classification for fiber separation from soybean meal (SBM), cottonseed meal (CSM) and wheat middlings (WM). The effect of yields of lighter fractions on fiber separation from size fractions was also investigated. At low yields of lighter fraction (5%), the quantity of fiber product separated was 3.7, 1.3 and 4.8% by weight of SBM, CSM and WM respectively. At high yields of lighter fractions (15%), the quantity of …

Go to article

Cocaine And Mefloquine-Induced Acute Effects In Ventral Tegmental Area Dopamine And Gaba Neurons, David Wilbanks Allison Dec 2009

Cocaine And Mefloquine-Induced Acute Effects In Ventral Tegmental Area Dopamine And Gaba Neurons, David Wilbanks Allison

Theses and Dissertations

The aim of the two studies presented here was to evaluate the effects of cocaine and mefloquine (MFQ) on γ-aminobutyric acid (GABA) and dopamine (DA) neurons in the ventral tegmental area (VTA). Cocaine: In vivo, lower doses of intravenous cocaine (0.25-0.5 mg/kg), or methamphetamine (METH), enhanced VTA GABA neuron firing rate via D2/D5 receptor activation. Higher cocaine doses (1.0-2.0 mg/kg) inhibited their firing rate. Cocaine and lidocaine inhibited the firing rate and spike discharges induced by stimulation of the internal capsule (ICPSDs) at dose levels 0.25-2 mg/kg (IC50 1.2 mg/kg), but neither DA nor METH reduced ICPSDs. In VTA …

Go to article

A Physical Model Of Human Skin And Its Application For Search And Rescue, Abel S. Nunez Dec 2009

A Physical Model Of Human Skin And Its Application For Search And Rescue, Abel S. Nunez

Theses and Dissertations

For this research we created a human skin reflectance model in the VIS and NIR. We then modeled sensor output for an RGB sensor based on output from the skin reflectance model. The model was also used to create a skin detection algorithm and a skin pigmentation level (skin reflectance at 685nm) estimation algorithm. The average root mean square error across the VIS and NIR between the skin reflectance model and measured data was 2%. The skin reflectance model then allowed us to generate qualitatively accurate responses for an RGB sensor for different biological and lighting conditions. To test the …

Go to article

An Empirical Methodology For Engineering Human Systems Integration, Nicholas S. Hardman Dec 2009

An Empirical Methodology For Engineering Human Systems Integration, Nicholas S. Hardman

Theses and Dissertations

The systems engineering technical processes are not sufficiently supported by methods and tools that quantitatively integrate human considerations into early system design. Because of this, engineers must often rely on qualitative judgments or delay critical decisions until late in the system lifecycle. Studies reveal that this is likely to result in cost, schedule, and performance consequences. This dissertation presents a methodology to improve the application of systems engineering technical processes for design. This methodology is mathematically rigorous, is grounded in relevant theory, and applies extant human subjects data to critical systems development challenges. The methodology is expressed in four methods …

Go to article

First Prev Next Last