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Biomass-To-Biofuels' Supply Chain Design And Management, Ambarish Madhukar Acharya

Theses and Dissertations

The goal of this dissertation is to study optimization models that integrate location, production, inventory and transportation decisions for industrial products and apply the knowledge gained to develop supply chains for agricultural products (biomass). We estimate unit cost for the whole biomass-to-biofuels’ supply chain which is the per gallon cost for biofuels up till it reaches the markets. The unit cost estimated is the summation of location, production, inventory holding, and transportation costs. In this dissertation, we focus on building mathematical models for designing and managing the biomass-to-biofuels’ supply chains. The computational complexity of the developed models makes it advisable …

A Revision Of The New World Species Of Donacaula Meyrick And A Phylogenetic Analysis Of Related Schoenobiinae (Lepidoptera: Crambidae), Edda Lis Martinez Calez

Theses and Dissertations

Phylogenetic relationships of 13 genera of Schoenobiinae (Lepidoptera: Crambidae) are postulated based on traditional characters of genitalia and wing venation and new characters of the descaled whole body. The phylogenetic analysis yielded one most-parsimonius tree (length 287 steps, CI= .36, RI= .62) that resulted in a monophyletic clade of all genera of Schoenobiinae examined. The monophyly of the Schoenobiinae is supported by a Bremer support value of five. Donacaula is not congeneric with the type-species of Schoenobius, S. gigantellus. The analysis confirms Lewvanich‘s hypothesis that Scirpophaga, Donacaula, Schoenobius, Catagela, and Helonastes are closely related. Based on this analysis, the New …

Enhanced Lipid Production And Biodiesel Yields From Activated Sludge Via Fermentation Of Lignocellulose Hydrolyzate, Andro Hernandez Mondala

Theses and Dissertations

The potential of enhancing lipid accumulation in municipal sewage activated sludge via fermentation of lignocellulose biomass hydrolyzate was investigated. The overall objective was to increase the levels of feedstock lipids in the activated sludge biomass and increase its biodiesel yield via in situ or ex situ transesterification; and improve its cost competitiveness as an abundant feedstock source for biofuels production. To reduce production costs and maintain environmental sustainability, influent wastewater and waste lignocellulose biomass hydrolyzate were used as cultivation media and substrate, respectively. However, lignocellulose hydrolyzates also contain degradation by-products such as furfural and acetic acid that are known to …

Innate Immunity And Inflammation In Sepsis In A Mouse Model For Binge Drinking, Basit Latief Jan

Theses and Dissertations

Alcohol consumption is a significant riskactor for mortality in patients with sepsis. This study was carried to investigate the mechanisms by which acute ethanol exposure alters the course of sepsis and the effect of TLR4 signaling. Ethanol administration decreases resistance to E. coli and causes decrease in the ability to clear bacteria both from the peritoneal-cavity as well as the spleen. At early time-points, ethanol also suppresses the production of pro-inflammatory cytokines. TLR4 is dispensable for survival in E. coli sepsis but it also contributes to lethality in wild-type mice. Although TLRs have been implicated as an important element of …

Fiber Loop Ringdown Evanescent Field Sensors, Chamini Saumya Herath

Theses and Dissertations

We combine the evanescent field (EF) sensing mechanism with the fiber loop ringdown (FLRD) sensing scheme to create FLRD-EF sensors. The EF sensor heads are fabricated by etching the cladding of a single-mode fiber (SMF), while monitoring the etching process by the FLRD technique in real-time, on-line with high control precision. The effect of the sensor head dimensions on the sensors' detection sensitivity and response time are investigated. The EF scattering (EFS) sensing mechanism is combined with the FLRD detection scheme to create a new type of fiber optic index sensor. The detection limit for an optical index change is …

Gasoline-Range Hydrocarbons Produced From Three Types Of Synthesis Gas Using A Mo/Hzsm-5 Catalyst, Jason Tyler Street

Theses and Dissertations

Biomass-derived hydrocarbons that include gasoline, diesel, and jet fuel will help replace finite fossil fuel hydrocarbons of the same range. This study showed that temperature could be controlled in a scaled-up reactor system using three types of syngas. The CO conversion, selectivity and amount of product created from each type of syngas were examined. Clean syngas composed of 40% H2, 20% CO, 12% CO2, 2% CH4, and 26 % N2 was used to test ideal stoichiometric molar values. Clean syngas composed of 19% H2, 20% CO, 12% CO2, 2% CH4, and 47 % N2 was used to test an ideal …

Occurrence And Transformation Of Pharmaceutical And Antibacterial Compounds In The Environment, Kusum Santosh Verma

Theses and Dissertations

The presence of pharmaceuticals and personal care products (PPCPs) in the environment has become a matter of concern during the last decade. Increased production of PPCPs along with their increased use has led to release of these compounds in the environment via various routes. PPCPs includes large group of compounds including veterinary and human antibiotics, analgesics and anti-inflammatory drugs, psychiatric drugs, β-blockers, X-ray contrasts, and steroid hormones, etc. Many of the compounds used in PPCPs have been shown to possess adverse effects to living organisms and act as endocrine disrupting agents (ECDs). This dissertation includes the investigation of the occurrence …

Spatio-Temporal Characteristics Of Mississippi Wildfires, Saranee Dutta

Theses and Dissertations

Based on wildfire data acquired from Mississippi forestry commission from 1991- 2005 approximately 4,000 wildfires occur in Mississippi each year, burning over 60,000 acres of forest and grassland. This study focuses on Mississippi’s wildfires from 1991- 2005 for the summer/fall period defined for this study as the May-November fire season. Statistical analysis indicates that there is significant correlation between vegetation indices derived from remotely sensed data and wildfire size at various time lag periods. Forest areas are correlated with vegetation indices at longer lag periods, nonorested areas are correlated at shorter lag periods. The inverse correlation between wildfire size and …

Poplar Interactions With Zinc For Use In Bioremediation And Monitoring, Joshua Pope Adams

Theses and Dissertations

Plant mechanisms regulating environmental heavy metal interactions are vital for plant survival. Plants must maintain adequate metal levels while preventing excesses. Several mechanisms involved in heavy metal uptake and sequestration have been identified and studied in hyperaccumulating plants such as Thlaspi caerulescens. These plants accumulate large quantities of metals, but their use in remediation is limited by their small size. On the other hand, mechanisms in high-biomass, non-hyperaccumulating perennial species such as poplar (Populus spp.) are unknown. The central goal of this project is to delineate specific mechanisms in poplar regulating the heavy metal zinc (Zn) for potential use in …

Screening Of New Commercial And Experimental Gossypium Hirsutum Cultivars For Tolerance To The Reniform Nematode (Rotylenchulus Reniformis), Julie Anna Blessitt

Theses and Dissertations

The reniform nematode is a major pest affecting common upland cotton in the United States. Management of this pest in cotton fields only gives partial control and is sometimes neither economical nor profitable. Past research has shown no resistance to the reniform nematode in currently available commercial cotton cultivars. Screenings of several currently available cotton cultivars for tolerance to the reniform nematode were conducted in the growing seasons of 2006 and 2007 at the Delta Branch Experiment Station in Stoneville MS. Several cultivars were identified as tolerant and productive including ‘Croplan Genetics 3520 B2RF,’ ‘DynaGrow 2520 B2RF,’ and ‘Stoneville 5242 …

Production Of Second Generation Biofuels From Woody Biomass, Sanjeev Kumar Gajjela

Theses and Dissertations

Increased research efforts have recently been accelerated to develop liquid transportation fuels from bio-oil produced by fast pyrolysis. However, these bio-oils contain high levels of oxygenated compounds that require removal to produce viable transportation fuels. A variety of upgrading technologies have been proposed, of which catalytic hydroprocessing of the raw bio-oil has appears to have the best potential due to the fact that no fractionation of the bio-oil is required prior to treatment. The objective of this research was to apply two-stage catalytic hydroprocessing to bio-oil with heterogeneous catalysts to produce hydrocarbon fuels. To achieve this objective seven catalysts were …

Organizational, Job, And Supervisory Antecedents And Consequence Of Job Embeddedness: The Case Of Vietnam, Vinh Q. Nguyen

Theses and Dissertations

A recent major development in the turnover literature is the introduction of the Job Embeddedness (JE) construct. JE is a multidimensional construct conceptualized as the combined forces that tend to keep an employee from leaving his or her job. Research has demonstrated that JE predicts voluntary turnover above and beyond the variables used in traditional turnover models. However, since it is a relatively new construct, JE has received very limited study, especially across cultures. Further research is needed in order to understand both antecedents and consequences of JE. This dissertation, therefore, investigates a range of presumed organizational, job, and supervisory …

Influences Of Artificial Reefs On Juvenile Red Snapper Along The Mississippi Gulf Coast, Jason Robert Brandt

Theses and Dissertations

Artificial reefs are important management tools for red snapper, Lutjanus campechanus, fisheries in the Northern Gulf of Mexico. I deployed fish traps (0.97 m long; 0.64 m height; 175 x 115 mm funnel mouth size) to collect red snapper < 406 mm total length (TL) associated with pyramid-shaped artificial reef structures (3.7 m triangular base; 2.4 m height; 3.2 metric tons) to evaluate two reef distribution designs: (1) five closely-spaced pyramid units, and (2) five closely-spaced pyramids with two sets of two pyramids at 30.5, 61.0, and 91.5 m from the five pyramids. In 26 sampling trips, 927 red snapper were captured. Catch per unit effort (fish/hour) did not differ significantly among patterns (P= 0.396). Red snapper lengths differed significantly among patterns (P= 0.005), with the largest mean total length (235 mm, SE= 5.14) occurring at the pattern with 61.0-m spacing.

The Economic Feasibility Of Producing Sweet Sorghum As An Ethanol Feedstock In Mississippi, Joseph Andrew Linton

Theses and Dissertations

This study examines the feasibility of producing sweet sorghum as an ethanol feedstock in Mississippi. An enterprise budgeting system is used along with estimates of transportation costs to estimate farmers’ breakeven costs for producing and delivering sweet sorghum biomass. This breakeven cost for the farmer, along with breakeven costs for the producer based on wholesale ethanol price, production costs, and transportation and marketing costs for the refined ethanol, is used to estimate the amounts that farmers and ethanol producers would be willing to accept (WTA) and willing to pay (WTP), respectively, for sweet sorghum biomass. These WTA and WTP estimates …

The Effect Of Exogenous Fructose On Creeping Bentgrass Heat Tolerance, William Brett Long

Theses and Dissertations

Creeping bentgrass (Agrostis stolonifera) used on golf course putting greens are some of the most intensively managed areas of turf and are subjected to high stress. Heat stress results in lowered photosynthetic efficiency and inadequate sugar production. An exogenous application of fructose could compensate for the lack of sugar being produced. The objectives of this research were to determine the effect of exogenous applications of fructose on heat stressed creeping bentgrass. Field results showed some phytotoxicity with high rates of fructose, while lower rates showed no visible damage compared to an untreated control. Low rates of surfactant resulted in little …

Utilization Of Extracted Hardwood Flakes For Manufacturing Oriented Strand Lumber, Thomas Eric Mcconnell

Theses and Dissertations

Lignocellulosic ethanol production currently uses expensive and harsh methods to extract wood sugars from small-diameter hardwood trees that otherwise would have little or no marketability. A byproduct that adds no value to the conversion process results, thus alternative methods are needed to make this fuel source cost-effective. This dissertation proposes only partially hydrolyzing southern hardwoods, extracting some polysaccharides for ethanol fermentation while leaving behind a modified wood material which could be used as furnish for manufacturing strand-based wood composites. Three treating solutions, 1% sulfuric acid, water, and 1% sodium hydroxide, along with untreated controls, were utilized in a partial hydrolysis …

Synthesis And Characterization Of Electrospun Gelatin/Dendrimer Scaffold Encapsulated With A Silver As A Potential Antimicrobial Wound Dressing, Alpana Dongargaonkar

Theses and Dissertations

A novel nanofiber scaffold was fabricated and characterized as a potential antimicrobial wound dressing. Half generation polyamidoamine (PAMAM) dendrimer G3.5 was covalently conjugated to gelatin. Gelatin alone or with gelatin-dendrimer conjugates was electrospun into nanofiber scaffolds. Gelatin is a derivative of natural collagen, and it is biocompatible, non-toxic and inexpensive, making it a desirable component in a wound dressing. Dendrimers are synthetic polymers comprising of a central core, internal branches and reactive surface groups. They provide a structurally controlled architecture for drug release. Silver was incorporated into the scaffold in situ due to its broad spectrum of antimicrobial properties. The …

Distribution And Molecular Analysis Of Avian Malaria Vectors On Four Central Virginia Prothonotary Warbler (Protonotaria Citrea) Breeding Sites, Catherine Wallace

Theses and Dissertations

Avian malaria is a devastating disease that has decimated numerous bird species. This study sought to identify the vectors of avian malaria at four central Virginia Prothonotary warbler breeding sites. Twenty one thousand mosquitoes were collected and Culex salinarius, Cx. erraticus, and Cx. pipiens/restuans were found to be the dominant species at these sites. Geographic factors, such as crop land and forest type, were determined to be potential indicators for species abundance variation between sites. Of the mosquitoes collected, ninety one (0.4%) were identified as blood fed. The blood fed mosquitoes were found to have fed on avian, mammalian, amphibian, …

Maternal Depressive Symptoms And Health Outcomes In Youths With Type 1 Diabetes: A Mediational Model, Struemph Kari Morgan

Theses and Dissertations

Objectives: The rate and impact of depressive symptoms were examined with two models based on known effects of depression on variables related to diabetes management, parental involvement and diabetes conflict. The proposed models will measure potential effects high maternal depressive symptoms may have on parental monitoring and involvement and diabetes specific conflict and how these variables may in turn relate to poor regimen adherence. Methods: Participants included 225 mothers and young adolescents (aged 11-14) with T1D. Diabetes self-care behaviors were measured with the 24 Hour Recall Interview, parental involvement and monitoring were measured with the Parent Management of Diabetes Scale, …

Mother-Infant Synchrony During Infant Feeding, Barbara Reyna

Theses and Dissertations

MOTHER-INFANT SYNCHRONY DURING INFANT FEEDING By Barbara A. Reyna, PhD A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2010. Major Director: Rita H. Pickler, PhD Endowed Nursing Alumni Professor Department of Family and Community Health Nursing, School of Nursing Synchrony between a mother and her infant is fundamental to their developing relationship. Feeding is an essential activity that provides an opportunity for interaction between a mother and her infant and may lead to synchronous interaction. The purpose this study was to develop and test a …

A Novel Method To Detect Functional Subgraphs In Biomolecular Networks, Sterling Thomas

Theses and Dissertations

Several biomolecular pathways governing the control of cellular processes have been discovered over the last several years. Additionally, advances resulting from combining these pathways into networks have produced new insights into the complex behaviors observed in cell function assays. Unfortunately, identification of important subnetworks, or “motifs”, in these networks has been slower in development. This study focused on identifying important network motifs and their rate of occurrence in two different biomolecular networks. The two networks evaluated for this study represented both ends of the spectrum of interaction knowledge by comparing a well defined network (apoptosis) with and poorly studied network …

Isolationism, Internationalism And The “Other:” The Yellow Peril, Mad Brute And Red Menace In Early To Mid Twentieth Century Pulp Magazines And Comic Books, Nathan Vernon Madison

Theses and Dissertations

This thesis’ purpose is to demonstrate, via the examination of popular youth literature (primarily pulp magazines and comic books) from the 1920s through to the 1950s, that the stories found therein drew their definitions of heroism and villainy from an overarching, nativist fear of outsiders that had existed before the Great War, but intensified afterwards. These depictions were transferred to America’s “new” enemies following both the United States’ entry into the Second World War, as well as the early stages of the Cold War. This transference of nativist imagery left behind the ethnically-based origins of such depictions, showing that racism …

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. …

Modern Public Library Building, Rineta Jashari

Theses and Dissertations

No abstract provided.

Characterization Of Watersheds On Fort Benning Military Reservation: Comparison Of Field Data To Watershed Parameters, Melinda Rosetta Stahl

Theses and Dissertations

Sixteen watersheds located on Fort Benning Military Installation in Georgia were analyzed using both physically collected data and computer modeling data. Physical data collected included total suspended solids (TSS) and grain size analysis using the Wolman Pebble Count method. Computer modeling analyzed the watersheds using ArcGIS 9.3 for comparison to physical data. Land use, slope, and soil data were used in a modified revised universal soil loss equation (RUSLE) to create a soil erodibility index map. Wolman Pebble Count data showed that in half of the watersheds, 84% of the sampled grains were less than half a millimeter in size. …

Perceptions Of Male Versus Female Students Enrolled In Science, Technology, Engineering And Mathematics Courses Regarding Peer Tutoring, A Component For Student Retention, Cheryl D. Kingsbury

Theses and Dissertations

Academic departments in the areas of science, technology, engineering, and mathematics, strive to develop in students the ability to problem solve, analyze, and to critically think about solutions to problems. Academic departments are committed to success, yet retention rates are lower than would be expected for females in science, technology, engineering, and mathematics fields of study, where female students are underrepresented.

The purpose of the study was to explore the perceptions of male and female traditional and nontraditional students who participated in a science, technology, engineering or mathematics STEM course during the spring 2010 semester regarding peer tutoring, and to …

Finding Myself: The Maturation Of Spirituality And Its Influence On Behavior During Late Adolescence, Deanna M. Mason

Theses and Dissertations

The purpose of this grounded theory study was to develop a theoretical model describing the influence of spirituality and/or religiosity on late adolescent behavior. Multiple quantitative research studies have linked spirituality and/or religiosity with both decreased health-risk behaviors and increased health-promotion behaviors during adolescence. However, as reductionist methods have not revealed underlying reasons for these relationships, the ability to apply this knowledge to practice is limited. Additionally, there is a lack of clear definitions for spirituality and/or religiosity firm enough to bridge disciplinary boundaries. A qualitative research perspective, which takes into account the embodied experience and development of individuals during …

Effects Of Fatigue And Self-Reported Countermeasures Used By Regional Airline Pilots Conducting Continuous Duty Overnight, Andrew Laventure

Theses and Dissertations

Fatigue poses a significant risk to commercial aviation. When pilots become fatigued they are more likely to make errors and in some instances those errors have been causal factors in accidents. Research not only tells us how the human body is affected by fatigue but also what can be done to temporarily reduce its negative impact on performance. However, relatively little data is available pertaining to one specific type of flight operation, the Continuous Duty Overnight (CDO). They are frequently conducted by regional airlines within the United States and typically resemble schedules for workers on a 3rd shift, otherwise known …

Air Traffic Controllers: Flying In The Face Of Danger? A Look Into The Effects Of The Time Of Day, Jason Boergerhoff

Theses and Dissertations

Since the events of September 11, this country has continued to grow and its commercial air travel along with it. As the number of passengers and planes increase, so must the skill and etermination of the air traffic controllers. They must be at their peak performance levels to ensure the flying public is handled safely and expeditiously. This study looks at the possible effects of the time of day. After defining time of day effects and giving some of the consequences of these effects, a look into the task of a controller was necessary. This study broke the task down …

Native American Students: Perceptions Of Lived Experiences Attending A Small Predominantly White University In The Upper Midwest, Dennis Richard Simons

Theses and Dissertations

The purpose of this qualitative study was to better understand the lived experiences of Native American students when studying on a predominantly white campus at a small university in the Upper Midwest. Using a phenomenological approach, the researcher interviewed each of the eight participants for one hour, although there were two interviews that took longer. Two participants agreed to meet for a second interview and, again, the time taken was approximately one hour. The resulting audio-recorded interviews were then transcribed, coded, and analyzed.

Three themes emerged from the analysis of the data. Theme One: Participants depended on the support of …