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Articles 301 - 330 of 397
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The Dirt On The Ancient Maya: Soil Chemical Investigations Of Ancient Maya Marketplaces, Daniel Aaron Bair
The Dirt On The Ancient Maya: Soil Chemical Investigations Of Ancient Maya Marketplaces, Daniel Aaron Bair
Theses and Dissertations
Various criteria or lines of evidence have been used to identify ancient Maya marketplaces, including location near trade routes, artifactual evidence of trade, open space adjacent to transportation routes, proximity to public structures, low platforms and rock alignments to denote market spaces, and regular patterns in soil and floor chemical concentrations. Seibal and Mayapán were important economic Maya polities controlling the trade routes at the apex of their civilizations. The objectives of these studies were to apply geochemical and geospatial analyses of the soils and floors from public plazas and household patios, to discover the anthropogenic chemical residues of phosphorus …
Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt
Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt
Theses and Dissertations
Climate has historically been recognized as an influence on sediment flux and deposition. The North American Monsoon is suggested as the forcing mechanism of deltaic progradational events of the Rio Grande River delta. Interpretations of reflection seismic profiles reveal that eustatic rise in sea-level from the Last Glacial Maximum to present is accompanied by several regressional events of the Rio Grande delta 5.5, 9.5, and 11.5 ka BP. Much of the migration of depositional facies within a delta system is forced by hinterland tectonics and base-level rise and fall. However, we suggest that the movement of facies within the Rio …
Investigating The Relationship Between The Policy Implementation Process And The Utilization Of Information Technology In A Constitutional Republic: The Case Of I-269 Nepa Process, Joseph Hampton Holland
Investigating The Relationship Between The Policy Implementation Process And The Utilization Of Information Technology In A Constitutional Republic: The Case Of I-269 Nepa Process, Joseph Hampton Holland
Theses and Dissertations
Information technologies (IT) have provided significant benefits for society. By drawing on the assumptions of the New Public Management (NPM) framework, the author investigates how, in one case, IT alters the policy implementation process. Additionally, the author tests reinforcement theory, sociotechnical theory, and technological determinism to determine which IT model best explains the utilization of IT at the Mississippi Department of Transportation (MDOT). This study examines the National Environmental Policy Act (NEPA) of 1969. By conducting interviews, analyzing documents, and examining a physical artifact, the author explores the administration of an economic impact analysis (EIA) that was conducted on the …
An Investigation Of Alumni Perceptions Of The Industrial Technology Undergraduate Program At Mississippi State University And Its Transferability To Industry, Heshium Lawrence
An Investigation Of Alumni Perceptions Of The Industrial Technology Undergraduate Program At Mississippi State University And Its Transferability To Industry, Heshium Lawrence
Theses and Dissertations
Industries have changed over the years and the necessary skills required for a person to obtain a position in industry have become more challenging. This study examined alumni perceptions regarding the Industrial Technology program at Mississippi State University and expanded on the literature that is currently available as there is limited information and literature regarding the perception of how alumni view the transferability of knowledge and skills gained in Industrial Technology programs to industry. Information on alumni perception‟s of their skills and knowledge gained would add pertinent facts to the limited research that is currently being published. There were 35 …
Acquisition Of Right Of Way For Highway Construction, Imad Aleithawe
Acquisition Of Right Of Way For Highway Construction, Imad Aleithawe
Theses and Dissertations
A key element in moving highway construction projects forward is the ability to acquire the Right of Way (ROW) in a timely manner. Delay in the acquisition process due to multitude of causes will usually lead to major construction phase delays. Identifying the delay factors allows for better time management of the process. A detailed review of the acquisition process at the Mississippi Department of Transportation (MDOT) is used as an example. Reviews of the process in neighboring states are also presented in order to determine other current practices and their likely impact on the acquisition duration. Descriptive and multivariable …
Screening Ornamental Pepper (Capsicum Annuum L.) Cultivars For Temperature Tolerance Using Pollen, Physiological And Seed Germination Parameters, Karande Gajanayake Mudiyanselage Chandana Preethi Bandara Gajanayake
Screening Ornamental Pepper (Capsicum Annuum L.) Cultivars For Temperature Tolerance Using Pollen, Physiological And Seed Germination Parameters, Karande Gajanayake Mudiyanselage Chandana Preethi Bandara Gajanayake
Theses and Dissertations
Temperature affects reproductive potential, aesthetic and commercial value of ornamental peppers. In experiment one, temperature effects were assessed in 12 ornamental cultivars using in vitro pollen germination and tube length, and the physiological parameters, cell membrane thermostability, chlorophyll stability index and canopy temperature depression. In experiment two, seed germination rate and maximum seed germination response to temperature were assessed. Cumulative temperature response indices (CTRI) for pollen, seed, and physiological parameters were derived and used to classify cultivars for temperature tolerance. CTRI based on pollen parameters showed significant, but poor correlation with physiological parameters. CTRI based on seed parameters showed significant …
Estimation Of Aboveground Terrestrial Net Primary Productivity And Analysis Of Its Spatial And Temporal Trends In The Conterminous United States From 1997 To 2007 Using Nasa-Casa Model, Sami Khanal
Theses and Dissertations
This study estimated monthly and annual Net Primary Productivity (NPP), an important indicator of carbon sequestration, in the Conterminous US from 1997 to 2007 using Carnegie-Ames-Stanford Approach. Vegetation condition, temperature, precipitation, photosynthetically active radiation and soil water holding capacity were used as model’s inputs. NPP values were lower than mean annual values during the year 2000 to 2003 which was probably due to extreme drought conditions during these years. Higher NPP per square meter was generally found in Savannah and Subtropical eco-divisions whereas Tropical/Subtropical deserts had the lowest NPP. Southeastern states had the highest NPP per square meter thus, made …
Spatial And Temporal Distribution Of Larval Fishes In A Large Tidal River., Harold Seelig
Spatial And Temporal Distribution Of Larval Fishes In A Large Tidal River., Harold Seelig
Theses and Dissertations
There are few published studies of larval fish assemblages from unregulated, tidal freshwater rivers. Patterns in the spatial and temporal distribution of larval fishes in the Mattaponi River were examined. Sampling took place on a weekly basis from February through August, 2006 and 2007. Larval fishes were categorized by taxa, reproductive guild, and residency guild. Group comparisons using multi-response permutation procedures (MRPP) indicated significant spatial and temporal differences in assemblage composition on multiple scales. Differences in assemblage composition were analyzed using non-metric multidimensional scaling (NMS). Interannual differences were attributable to anadromous and semi-migratory species. Seasonal differences were attributable to herrings, …
Patterns In Fish Community Structure In A Regulated River, Richard Davis
Patterns In Fish Community Structure In A Regulated River, Richard Davis
Theses and Dissertations
I examined the abundance, composition, and distribution of fish communities in the lower Roanoke River, a hydropeaking system in North Carolina. Fishes were sampled at before and after peaking events over three years; 2007 to 2009. I evaluated trends in species richness, diversity, and assemblage composition. There were no significant differences in either richness or diversity suggesting consistent trends in richness and diversity throughout the study. I used non-metric multidimensional scaling (NMDS) to create a community composition model. Fish composition was noticeably greater post-peaking and changed minimally across time and event. There were no statistically significant differences in species composition …
Nitrogen And Phosphorus Biomass-Kinetic Model For Chlorella Vulgaris In A Biofuel Production Scheme, William M. Rowley
Nitrogen And Phosphorus Biomass-Kinetic Model For Chlorella Vulgaris In A Biofuel Production Scheme, William M. Rowley
Theses and Dissertations
Chlorella vulgaris was cultured in microbioreactors using Bold’s Basal medium at varying nitrogen and phosphorus concentrations to define nitrogen and phosphorus utilization standards. Nutrient concentration was varied between 137 mg/L to 7.33 mg/L NO3-N and between 55.2 mg/L to11.0 mg/L PO4-P in five test scenarios. All were grown under a constant photoperiod at 22±2 °C and a mixture of 4 to 10% carbon dioxide/air. Maximum yield and growth rate occurred with the highest initial nitrogen and phosphorus concentrations. A statistically significant difference in biomass was found among all test levels at the end of the eight day growth period. Applying …
Modeling Of The Biomass Power Generation And Techno-Economic Analysis, Shireesha Methuku
Modeling Of The Biomass Power Generation And Techno-Economic Analysis, Shireesha Methuku
Theses and Dissertations
Biomass is one of the renewable energy sources being used widely for power generation. This research work includes developing a comprehensive model for a biomass based power generation system as well as analyzing the technical, economical, and environmental impacts. The research objectives include modeling of the system, stability studies, and sensitivity analysis using MATLAB/Simulink. A mathematical model for the gas turbine has been developed and successfully interconnected with the distribution network. Transient stability of the power system has been carried out for four bus and six bus test case systems. Maximum rotor speed deviation, oscillation duration, rotor angle, and mechanical …
Visual Perception And Gestalt Grouping In The Landscape: Are Gestalt Grouping Principles Reliable Indicators Of Visual Preference?, Mark Reinhardt Levy
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 …
Zooplankton Abundance, Community Composition And Grazing In The James River Estuary (Virginia, Usa), Laura E. Barry
Zooplankton Abundance, Community Composition And Grazing In The James River Estuary (Virginia, Usa), Laura E. Barry
Theses and Dissertations
This study examined the extent to which zooplankton in the James River Estuary (Virginia, USA) exploit the available algal-food resources. Zooplankton abundance, community composition and grazing rates were assessed at three locations which included a site with high algal production (near the VCU Rice Center) and two sites where algal production was lower. Grazing rates were measured by determining the rate of phytoplankton decline (as chlorophyll a) during 48-hour incubation experiments in the presence and absence of zooplankton. Significant differences in zooplankton abundance were observed among the three sites, with the greatest average zooplankton density (434 ± 69 ind/L) occurring …
Mobility And Population Change In Northeast Mississippi: An Object-Based Seriation Of Projectile Points As A Relative Paleodemographic Indicator, Jason L. Edmonds
Mobility And Population Change In Northeast Mississippi: An Object-Based Seriation Of Projectile Points As A Relative Paleodemographic Indicator, Jason L. Edmonds
Theses and Dissertations
Archaeological considerations of mobility have primarily focused on the differences in and among the kinds or degrees of mobility itself, rather than addressing the underlying issue of why human settlement patterns were or are mobile. The focus of this study is to address such questions within Darwinian evolutionary theory. Using the concepts of bet-hedging, as used in biology, and waste, as used in archaeology, it is argued that mobility was selectively favored for its population limiting properties. Relative changes in the numbers of projectile points in each assigned class, ordered chronologically by seriation, were taken to indicate relative population change …
Changing Currents: Interpreting The Promise Of The Tennessee-Tombigbee Waterway, Nathan Horn
Changing Currents: Interpreting The Promise Of The Tennessee-Tombigbee Waterway, Nathan Horn
Theses and Dissertations
At the time of its construction (1971-1985), the Tennessee-Tombigbee Waterway was a highly scrutinized public works project, but the years after its construction have remained largely unexplored. Research in the John C. Stennis Collection, U.S. Army Corps of Engineers and Tennessee-Tombigbee Waterway Development Authority archives, and local newspapers, revealed that despite developers’ promise the waterway’s economic impact failed to live up to expectations, while its environmental influence more than exceeded them. Though rural southerners failed to benefit economically from the waterway, they embraced the environmental changes forced upon the project by the National Environmental Policy Act. Built as a promise …
Alternative Fuels For Ground Support Equipment, Samuel Enlof
Alternative Fuels For Ground Support Equipment, Samuel Enlof
Theses and Dissertations
Airlines are in desperate need of reliable methods and materials to save and transform traditional ground operation fuel. This topic has taken precedence within the airline and aviation industries due to alarming product costs in accordance with the dilapidation of global and domestic economies. This is also in conjunction with similarly volatile geo-environmental atrocities being committed at an alarming rate-- often due to harsh chemicals and other pollutants evoked by the airline industry. It is imperative to determine which alternative fuels are conducive to the modern airline industry. The advantages and disadvantages of each alternative fuel needs to be evaluated …
Factors Limiting Benthic Algal Abundance In Virginia Streams Of The Coastal Plain, Michael Brandt
Factors Limiting Benthic Algal Abundance In Virginia Streams Of The Coastal Plain, Michael Brandt
Theses and Dissertations
Algae are important components of stream food webs and often used in biomonitoring assessments. Little is known regarding the factors that limit their abundance in streams of the VA Coastal Plain. The surficial geology of the Coastal Plain is predominately sandy deposits which comprise the dominant substrate in streams of this region. In a comparative study of five streams located near the VCU Rice Center, we quantified substrate composition, light availability, and nutrient concentrations to assess their relative importance in determining benthic algal abundance. The proportion of stream area comprised of hard substrates was a significant predictor of variation in …
An Evaluation Of Bacterial And Fungal Contributions To Organic Matter Decomposition Along A Soil Moisture Gradient, Morgan Rawls
An Evaluation Of Bacterial And Fungal Contributions To Organic Matter Decomposition Along A Soil Moisture Gradient, Morgan Rawls
Theses and Dissertations
The decomposition of plant litter is a critical biological function that aids in nutrient cycling and energy transfers within and between ecosystems. The primary decomposers of dead leaf material are bacteria and fungi, though there is no consensus as to which of these groups is dominant, nor is it known how the abundance and composition of these communities changes over time. The objectives of this study were to examine the relative contributions of bacterial and fungal populations to leaf organic matter (OM) decomposition and to consider the effect of moisture availability on the microbial community. The study was conducted across …
Presence Of Haemosporidia And Flaviviruses In Breeding Prothonotary Warblers (Protonotaria Citrea): An Analysis Of Spatial And Temporal Trends In Infection Prevalence And Associations With Reproductive Success, Elena Grillo
Theses and Dissertations
As Neotropical migratory birds, Prothonotary Warblers are exposed to parasites in both tropical and temperate regions and may act as dispersal agents between geographic areas. This study identifies the prevalence of Haemosporidia, West Nile Virus (WNV), and St. Louis Encephalitis virus (SLEV) in this species. A total of 71.6% of captured Prothonotary Warblers were infected with Haemosporidia during the 2008 breeding season, and infection prevalence increased throughout the season. This temporal change in prevalence is likely due to infection relapse and transmission of new infections. No correlations between reproductive effort and infection status were observed, nor were any associations between …
Differentiated Interdisciplinary Science Instruction In A Fourth Grade Inclusion Classroom, Laura Oliver
Differentiated Interdisciplinary Science Instruction In A Fourth Grade Inclusion Classroom, Laura Oliver
Theses and Dissertations
This action research project explored what would happen if interdisciplinary, differentiated instruction was used during a science unit on recycling in a fourth grade inclusion classroom of 20 students. The project also focused in particular on the progress of two throughout the project's implementation. Four differentiated techniques were used throughout the unit. These included a tiered writing assignment, student choice based on interests, centers, and a RAFT, which was a summative assessment that allowed for student creativity based on their own interests and readiness. Using field notes, journal entries, student grades, and student surveys the data revealed a notable difference …
Using Author Studies To Incorporate Multicultural Literature Across The New Jersey Core Curriculum, Carol Lynn Raines-Sapp
Using Author Studies To Incorporate Multicultural Literature Across The New Jersey Core Curriculum, Carol Lynn Raines-Sapp
Theses and Dissertations
The purpose of this study was to incorporate one author's work of multicultural literature to determine its significance in other subject areas within the New Jersey Core Curriculum exclusive of Language Arts/Literacy curriculum. It was to provide media specialists and classroom teachers with integral skills, concepts and ideas found in multicultural literature. The study used one author study, Virginia Hamilton, and one culture, African American in its evaluation within the New Jersey Core Curriculum Content Standards. The study showed that readability level of the selected works by Virginia Hamilton was excellent for students in grades four through six. Also, it …
The Walter And Inger Rice Center For Environmental Through Time: A Study In Environmental Change, Human Land Use And Its Effects Along The Lower James River, Chris Egghart
Theses and Dissertations
Historic cartographic sources, historical accounts, and ethnographic and archaeological data are used help reconstruct past settlement patterns and land uses that together acted to shape the changing cultural landscape of the Virginia Commonwealth University Walter and Inger Rice for Environmental Studies (Rice Center). The Rice Center is located in Charles City County along the north bank of the James River between Richmond and Williamsburg. Presented is a baseline description of the present day condition of the Rice Center property. This is followed by a detailed account of the physiographic and ecological changes that occurred along the Lower James River since …
An Environmental And Economic Assessment Of Future Municipal Solid Waste Disposal: A Case Study Of Select High Growth Regions Of Virginia., Joseph Krouse
Theses and Dissertations
This research analyzed environmental and economic factors associated with municipal solid waste (MSW) management of select high growth Planning District Commissions (PDCs) of Virginia. Current MSW management scenarios were compared to future hypothetical scenarios utilizing a regional landfill or waste-to-energy (WTE) combustion facility. Life-cycle inventory and full cost accounting methods of the Municipal Solid Waste Decision Support Tool, developed by the Environmental Protection Agency (EPA), were utilized to estimate annualized environmental emissions and economic costs. Model results and analysis indicate that a regional landfill would be the least cost intensive MSW management strategy in comparison to current management methods; however …
Hyperspectral Reflectance For Rapid Viability Assessment Of Bacillus Endospores, Jarrod Edwards
Hyperspectral Reflectance For Rapid Viability Assessment Of Bacillus Endospores, Jarrod Edwards
Theses and Dissertations
A study was conducted to optically determine the viability of the Gram +, endospore-forming bacterial genera Bacillus using a hyperspectral reflectance spectrometer. Endospores are a dormant, differentiated cellular capsule form taken by select bacteria to ensure survival when environmental conditions become unfavorable. Two species of Bacillus were used for this study, Bacillus megaterium and Bacillus subtilis. These endospores were killed using a chemical treatment of sodium hypochlorite or a physical treatment of heat and pressure in an autoclave. The treated samples along with viable samples were lyophilized to form a powder. A reflectance spectrometer measuring 350 nm to 2500 nm …
Elemental Composition And Nutrient Effect On The Uptake And Metabolism Of Dissolved Organic Carbon By Bacteria From A Temperate Region River, Anne Stuart
Theses and Dissertations
Rivers are arteries that connect land and sea, and provide a conduit and reactor for allochthonous and autochthonous organic carbon sources (OC) delivered to the coastal ocean. In comparison to marine waters, inland waters quantitatively represent only a fraction of the marine system; however, their importance to global C cycling maybe disproportional to its actual size. Inland systems are subject to multiple sources of OC (autochthonous and allochthonous) that vary individually in space and time with respect to their concentration and potential bacterial bioavailability. This study investigates the impact of high and ambient inorganic nutrient concentrations on the bacterial bioavailability …
The Responses Of Blue Crabs (Callinectes Sapidus) To Hypoxia/Hypercapnia In Freshwater, James Martin
The Responses Of Blue Crabs (Callinectes Sapidus) To Hypoxia/Hypercapnia In Freshwater, James Martin
Theses and Dissertations
The present research examined respiratory responses of blue crabs to long term (4, 13, and 21 days) hypercapnic hypoxia in freshwater at 23 C. Hypoxic conditions (50-60 & 75-85 mmHg O2) were induced by allowing the crabs to consume their oxygen supply, resulting in a hypercapnic induced decrease in pH that remained through the exposure. Postbranchial hemolymph responses to hypoxia/hypercapnia in freshwater demonstrate decreases in PO2, increases in PCO2, and decreases in pH. Lactate levels decreased over time, but hemocyanin concentration was highly variable with no trends. PH, lactate, and hemocyanin observations also demonstrated high variability and a variety of …
Role Of Bcl-2 Family Members To Promote Glucocorticoid –Induced Apoptosis By Mek Inhibitors In Leukemic Cells, Anila Rambal
Role Of Bcl-2 Family Members To Promote Glucocorticoid –Induced Apoptosis By Mek Inhibitors In Leukemic Cells, Anila Rambal
Theses and Dissertations
Glucocorticoids (GC) are common components of many chemotherapeutic regimens for lymphoid malignancies. GC-induced apoptosis involves an intrinsic BCL-2 family-regulated pathway. It has been shown that BIM (BCL-2 interacting mediator of cell death), a BH3-only pro-apoptotic protein, is up-regulated by dexamethasone (Dex) treatment in acute lymphoblastic leukemia (ALL) cells. Furthermore, BIM is inactivated by extracellular signal-regulated kinase (ERK)-mediated phosphorylation. We therefore hypothesized co-treatment with Dex and MEK/ERK inhibitors would promote apoptosis in ALL cells through BIM up-regulation and activation. We show here that a MEK inhibitor, PD184352 synergistically enhances Dex lethality in CCRF-CEM (T-ALL) cells. Co-treatment with Dex and PD184352 results …
Factors Affecting Dissolved Oxygen Metabolism In Coastal Plain Streams Of Virginia, Julie Frank
Factors Affecting Dissolved Oxygen Metabolism In Coastal Plain Streams Of Virginia, Julie Frank
Theses and Dissertations
I investigated seasonal and inter-site variation in factors influencing diel dissolved oxygen (DO) metabolism at four streams in the Virginia Coastal Plain. Data were collected monthly from January to August 2008 to characterize DO metabolism (diel DO amplitude, production, respiration), incident solar radiation (PAR), dissolved nutrients, fine benthic materials (mass, C:N, Chlα) and hydrology (discharge, water transit time, transient storage). Reach-scale metabolism estimates were determined using the one-station diurnal DO technique and transit time and transient storage were determined by conservative tracer additions. Incident solar radiation was the primary determinant of DO metabolism as streams experiencing higher light levels (Herring …
Patterns Of Abundance Across An Urban-Rural Gradient For Commonly Found Indigenous Arthropods, David Jones
Patterns Of Abundance Across An Urban-Rural Gradient For Commonly Found Indigenous Arthropods, David Jones
Theses and Dissertations
Abstract Proof of concept for a continuous environmental sampling methodology that employs common terrestrial arthropods as environmental samplers was tested by analyzing pitfall, malaise and black light captures over a six month period over a replicated urban-suburban-rural gradient in Central Virginia. All arthropods captured at the nine sites were identified and assigned to aquatic, vegetation, or soil groups based on their association with these microhabitats. To offset variability in arthropod life history patterns and species abundance within habitat types, arthropod categories based on presence/absence data over the six month period were constructed to provide for sampling reliability within each microhabitat …
Coupling Of Autotrophic And Heterotrophic Plankton Food Web Components In The Tidal-Freshwater James River, Usa, Matthew Beckwith
Coupling Of Autotrophic And Heterotrophic Plankton Food Web Components In The Tidal-Freshwater James River, Usa, Matthew Beckwith
Theses and Dissertations
Empirical studies have shown that algal- and detrital-based food web components are coupled in many pelagic systems as algal carbon enhances bacterioplankton production and growth efficiencies. Such phyto-bacterioplankton coupling impacts carbon flow through plankton food webs, yet the extent of coupling is poorly understood in systems receiving large amounts of allochthonous carbon. To investigate this issue, bacterioplankton abundance (BA) and community composition were compared to chlorophyll a concentrations and phytoplankton production in the tidal-freshwater James River (VA). BA averaged 107 cells mL-1 and was significantly related to chlorophyll a, phytoplankton production, and DOC concentrations. Analysis of DOC quality using fluorescence …