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The Influence Of Two Estrogens On The Sex And Ovarian Development Of Eastern Oysters (Crassostrea Virginica) Maintained In A Closed Recirculating System, Wesley Michael Burnside Jan 2010

The Influence Of Two Estrogens On The Sex And Ovarian Development Of Eastern Oysters (Crassostrea Virginica) Maintained In A Closed Recirculating System, Wesley Michael Burnside

LSU Master's Theses

As a multi-million dollar industry, production of the eastern oyster Crassostrea virginica is significant to the economy of the nation’s coastal regions. The cost of commercial oyster aquaculture has higher inputs than the oyster fishery, but larger, better quality oysters can be produced for culture by the stable availability of triploid individuals.

The goal of this project was to determine if the use of an estrogen, estradiol-17β or estradiol-3-benzoate, at a consistent environmental temperature would increase the percentage of females in a population, as well as ovarian development of eastern oysters. Ultimately, this could be applied to triploids to increase …


Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis Jan 2010

Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis

LSU Doctoral Dissertations

With the expansion of the human population and associated industries there is a concomitant increase in both resource utilization and the production of waste and deleterious by-products. Mercury is a naturally-occurring toxic metal with a complicated and unique biogeochemical cycle, and is often a contaminant of ecotoxicological concern in unindustrialized aquatic habitats. The research described herein was designed to elucidate multiple aspects regarding the behavior of mercury in oligohaline wetland habitats, particularly with respect to edaphic and vegetative effects, through a monitoring and characterization study as well as a series of manipulative experiments. The observational study, conducted in the wetlands …


Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray Jan 2010

Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray

LSU Master's Theses

The Louisiana Gulf Coast is an important wintering area for North American gadwall (Anas strepera). Conservation of winter habitat is a top priority of the Gulf Coast Joint Venture. Quantitative estimates of habitat use by wintering gadwall would help improve energetic demand models and subsequent estimates of habitat requirements. I used satellite telemetry (PTTs) to estimate winter habitat and refuge uses, spring migration chronology and corridors, as well as inter- and intra-regional winter movements of females. I used a split-plot MANOVA to evaluate the effects of individual females, female age, winter, hunt periods within winter, time of day, and all …


Variations In Synechococcus Cell Quotas Of Phosphorus, Sulfur, Manganese, Iron, Nickel, And Zinc Within Mesoscale Eddies In The Sargasso Sea, Benjamin S. Twining, Daliangelis Nunez-Milland, Stefan Vogt, Rodney S. Johnson, Peter N. Sedwick Jan 2010

Variations In Synechococcus Cell Quotas Of Phosphorus, Sulfur, Manganese, Iron, Nickel, And Zinc Within Mesoscale Eddies In The Sargasso Sea, Benjamin S. Twining, Daliangelis Nunez-Milland, Stefan Vogt, Rodney S. Johnson, Peter N. Sedwick

OES Faculty Publications

The quotas of P, S, Mn, Fe, Ni, and Zn in individual Synechococcus cells collected from the surface and deep chlorophyll maximum (DCM) layer of three mesoscale eddies in the Sargasso Sea were measured using synchrotron X-ray fluorescence microscopy. Cells in a mode-water eddy had significantly higher P (57 +/- 10 amol) and Mn (28 +/- 7 zmol) cell quotas than cells collected from a cyclone (22 +/- 2 amol and 10 +/- 1 zmol, respectively) or anticyclone (25 +/- 3 amol and 18 +/- 3 zmol, respectively). Conversely, Ni and Zn quotas were significantly higher in the cells from …


The Influences Of Microbial Diversity On Carbonate Geochemistry Across A Transition From Fresh To Saline Water In The Edwards Aquifer, Texas, Cassie Jo Gray Jan 2010

The Influences Of Microbial Diversity On Carbonate Geochemistry Across A Transition From Fresh To Saline Water In The Edwards Aquifer, Texas, Cassie Jo Gray

LSU Master's Theses

Microbially-mediated karstification through the production of metabolic byproducts has been well-documented in cave environments, but less is known about deep karstic settings. This research aimed to distinguish between microbial and geochemical influences on carbonate dissolution in the Edwards Aquifer, a prolific karst aquifer in central Texas, specifically from a transect of six wells across a transition from fresh to saline water in New Braunfels. For the first time, a portion of the aquifer’s bacterial diversity was examined from molecular 16S rRNA gene sequence analyses, which revealed that Alphaproteobacteria, Gammaproteobacteria, and Betaproteobacteria dominated the aquifer, with rare Bacteroidetes, Nitrospirae, and Firmicutes …


Predicting Flavonoid Ugt Regioselectivity With Graphical Residue Models And Machine Learning., Arthur Rhydon Jackson Dec 2009

Predicting Flavonoid Ugt Regioselectivity With Graphical Residue Models And Machine Learning., Arthur Rhydon Jackson

Electronic Theses and Dissertations

Machine learning is applied to a challenging and biologically significant protein classification problem: the prediction of flavonoid UGT acceptor regioselectivity from primary protein sequence. Novel indices characterizing graphical models of protein residues are introduced. The indices are compared with existing amino acid indices and found to cluster residues appropriately. A variety of models employing the indices are then investigated by examining their performance when analyzed using nearest neighbor, support vector machine, and Bayesian neural network classifiers. Improvements over nearest neighbor classifications relying on standard alignment similarity scores are reported.


From The Bronx Into The Wild! My Adventurous Experience At The Bronx Zoo, Lauren Noll Dec 2009

From The Bronx Into The Wild! My Adventurous Experience At The Bronx Zoo, Lauren Noll

Student Theses 2001-2013

Many people defend zoos, claiming that they provide great opportunities in education, scientific research, and the overall preservation of wildlife worldwide. However, many people will take the opposing side, arguing that it is wrong to deprive animals of their natural habitats and lifestyles. One of the greatest controversies of our time pertains to the moral issues associated with keeping animals in captivity, such as in zoos and aquariums.


Heirloom And Hybrid Tomato Yield And Quality In Organic And Conventional Production Systems, Diana J. Edlin Dec 2009

Heirloom And Hybrid Tomato Yield And Quality In Organic And Conventional Production Systems, Diana J. Edlin

Masters Theses & Specialist Projects

Due to the recent changes in the economy of Kentucky tobacco production, some producers are seeking an alternative crop that will provide similar economic gains to tobacco without needing more acreage. Tomatoes are an existing crop in Kentucky that have been declining in acreage over the last five years. There is evidence to suggest that, through niche and local marketing, tomatoes may be able to fill the void left by tobacco. However, there is concern among producers that they will lose yield and/or quality if they switch to one of these niche production systems or cultivars.

A two year study …


Department Of Chemistry News For Alumni And Friends, December 2009, Illinois State University, Department Of Chemistry Dec 2009

Department Of Chemistry News For Alumni And Friends, December 2009, Illinois State University, Department Of Chemistry

Chem Letter

Newsletter of the Illinois State University Department of Chemistry


Sci-Tech Contributed Papers For The 2010 Sla Conference Dec 2009

Sci-Tech Contributed Papers For The 2010 Sla Conference

Sci-Tech News

No abstract provided.


The Effects Of Pulsed Exposures Of Suspended Clay On The Survival, Growth, And Reproduction Of Daphnia Magna, Sarah Robinson Dec 2009

The Effects Of Pulsed Exposures Of Suspended Clay On The Survival, Growth, And Reproduction Of Daphnia Magna, Sarah Robinson

All Theses

Suspended sediments are a natural component of aquatic ecosystems but anthropogenic activity such as land development can result in significant increases, especially following rain events due to surface erosion. Continuous exposures of suspended clay and silt have been shown to effect growth and reproduction of Cladocera, leading to a decrease in population growth rate. The mechanism of clay toxicity in these filter-feeding organisms is clogging of the gut tract resulting in decreased food uptake and assimilation. When placed in clean water, daphnids can purge clay from their gut and recover. In many surface waters, aquatic organisms experience episodic exposures of …


The Malawi Project: From Conventional To Holistic Decision Making, Grace Wetmore Dec 2009

The Malawi Project: From Conventional To Holistic Decision Making, Grace Wetmore

Animal Science

How the Cal Poly Malawi Appropriate Technologies Team, and other development groups, can use Holistic Management to aid developing countries in an effort towards a sustainable future.


Costs Of Implementing Collective Action And Capacity Building Among Pastoralists In Southern Ethiopia, D. Layne Coppock, Seyoum Tezera, Solomon Desta Dec 2009

Costs Of Implementing Collective Action And Capacity Building Among Pastoralists In Southern Ethiopia, D. Layne Coppock, Seyoum Tezera, Solomon Desta

Environment and Society Faculty Publications

Since 2000, the PARIMA project has implemented risk-management activities among semi-settled pastoralists in southern Ethiopia. The goal has been to improve human welfare via collective action and capacity building. Outcomes include progress in income generation, asset conservation, and livelihood diversification. Fifty-nine collective-action groups were created. Dominated by women, they included over 2,000 founding members and groups have recently merged to form 37 cooperatives, consistent with government policy. Creating sustainable impacts via collective action and capacity building requires many inputs. Taking raw, illiterate volunteers and transforming them into sustainable groups took up to three years, on average. Costs of implementing this …


Eleven Years Of Parima Activities In North-Central Kenya: Impacts On Egerton University And Neighboring Communities, D. Layne Coppock, Abdillahi Aboud, Mark Mutinda, Stellamaris Muthoka Dec 2009

Eleven Years Of Parima Activities In North-Central Kenya: Impacts On Egerton University And Neighboring Communities, D. Layne Coppock, Abdillahi Aboud, Mark Mutinda, Stellamaris Muthoka

Environment and Society Faculty Publications

The PARIMA project was created to improve the well-being of pastoralists and agro-pastoralists in northern Kenya and southern Ethiopia via risk-management research, training, and outreach. The project began to collaborate with Egerton University’s Department of Natural Resources in 1998 and many joint activities were undertaken over the next 11 years. Among them were regional household research on pastoral risks and their management, a training program for Egerton teaching staff to obtain post-graduate degrees, facilitation of Egerton faculty and staff to attend professional meetings, and provision of computer hardware and software that led to the creation of a GIS teaching and …


Simple Cooling Method Improves The Quality Of Marketed Camel Milk In Northern Kenya, D. Layne Coppock, A. O. Adongo, F. Wayua, I. J. Sagalla, H. K. Walaga, C. Amboga Dec 2009

Simple Cooling Method Improves The Quality Of Marketed Camel Milk In Northern Kenya, D. Layne Coppock, A. O. Adongo, F. Wayua, I. J. Sagalla, H. K. Walaga, C. Amboga

Environment and Society Faculty Publications

Milk marketing is important for many pastoralists to generate income, especially poor households with little else to sell. Milk is accumulated at pastoral settlements and transported to local markets on foot, by pack animals, or in vehicles. Despite challenges of heat and long-distance travel, pastoralists or traders do not attempt to cool marketed milk and possibly reduce risk of spoilage. Milk spoilage is an important problem that limits urban consumer demand. Our research objective was to determine effects of water-soaked hemp (burlap), wrapped around plastic jerry cans, on reducing milk temperature and enhancing quality of marketed camel milk, a key …


Can Pastoral Linkages To Livestock Markets Be Sustained In Southern Ethiopia?, D. Layne Coppock, Getachew Gebru, Solomon Desta, Seyoum Tezera, Zewdu Edea Dec 2009

Can Pastoral Linkages To Livestock Markets Be Sustained In Southern Ethiopia?, D. Layne Coppock, Getachew Gebru, Solomon Desta, Seyoum Tezera, Zewdu Edea

Environment and Society Faculty Publications

The PARIMA project has facilitated collective action, empowerment of women, and increased involvement in livestock marketing among pastoralists on the Borana Plateau since 2001. Fifty-nine collective-action groups formed by PARIMA and her partners have been recently merged into market-oriented cooperatives, consistent with government policy. We used focus groups and participatory appraisals to assess the extent that market linkages have been sustained since previously reported in 2006. The markets have been growing, but are volatile. Members report they need access to early warning and livestock market-information systems, as well as more capital, to promote trade. Export firms have imposed added conditions …


Functional Characterization Of Calcium Dependent Protein Kinase 32 From Arabidopsis, Rucha Karve Dec 2009

Functional Characterization Of Calcium Dependent Protein Kinase 32 From Arabidopsis, Rucha Karve

All Dissertations

Calcium-dependent protein kinases (CPKs) are major plant Ca2+ sensors, many of which have roles in plant stress responses. The Arabidopsis genome encodes 34 CPK isoforms. Here we report characterization of AtCPK32 gene function. Analysis of transgenic plants expressing pCPK32-GUS shows that CPK32 is highly expressed in roots, pollen and embryo, as well as leaf hydathodes, and the abscission zone of mature siliques. Real time RT-PCR and promoter expression patterns show that CPK32 is responsive to abiotic and biotic stresses. Plants treated with salt, ABA, osmotic stress (PEG), wounding, and flagellin 22 peptide show up-regulation of CPK32 upon these stress treatments. …


Survival Analysis With Error-Prone Time-Varying Covariates: A Risk Set Calibration Approach, Xiaomei Liao, David M. Zucker, Yi Li, Donna Spiegelman Nov 2009

Survival Analysis With Error-Prone Time-Varying Covariates: A Risk Set Calibration Approach, Xiaomei Liao, David M. Zucker, Yi Li, Donna Spiegelman

Harvard University Biostatistics Working Paper Series

No abstract provided.


Lot Quality Assurance Sampling (Lqas) And The Mozambique Malaria Indicator Surveys, Caitlin Biedron, Marcello Pagano, Bethany L. Hedt, Albert Kilian, Amy Ratcliffe, Samuel Mabunda, Joseph J. Valadez Nov 2009

Lot Quality Assurance Sampling (Lqas) And The Mozambique Malaria Indicator Surveys, Caitlin Biedron, Marcello Pagano, Bethany L. Hedt, Albert Kilian, Amy Ratcliffe, Samuel Mabunda, Joseph J. Valadez

Harvard University Biostatistics Working Paper Series

No abstract provided.


Diet Composition Of Swordfish, Xiphias Gladius, Within The Straits Of Florida, Amy Marie Heemsoth Nov 2009

Diet Composition Of Swordfish, Xiphias Gladius, Within The Straits Of Florida, Amy Marie Heemsoth

HCNSO Student Theses and Dissertations

A diet study of swordfish, Xiphias gladius, was conducted in the Straits of Florida from April 2007 to December 2008. The stomachs of 131 swordfish were analyzed. Thirteen species of teleosts, three species of cephalopods, and one species of crustacean were observed in the diet. Cephalopods dominated the swordfish diet by weight (73.38%), number (69.90%), and occurrence (80.91%) and ranked highest in importance in the diet when calculating the index of relative importance (IRI). Teleosts followed by weight (25.16%), number (26.34%), occurrence (68.18%), and IRI (3,510.97). The prey species with the greatest dietary importance was Illex sp followed by …


Ua23 New Learning Approach, Aurelia Spaulding Nov 2009

Ua23 New Learning Approach, Aurelia Spaulding

ALIVE Center Publications

No abstract provided.


Full Issue: Vol. 63, Issue 4 Nov 2009

Full Issue: Vol. 63, Issue 4

Sci-Tech News

No abstract provided.


Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood Oct 2009

Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96h, and solutions were analyzed for ammonium, …


Extended Grazing And Reduced Stored Feed, Edward N. Ballard Oct 2009

Extended Grazing And Reduced Stored Feed, Edward N. Ballard

Kentucky Grazing Conference

Feed costs represent the major cost in most livestock production systems. A recently completed analysis of 225 Standardized Performance Analysis (SPA) Beef Cow Records on herds in Illinois and Iowa showed that feed cost was the overriding factor determining profitability, explaining over 57 percent of the herd-to-herd variation. Typically the cost of supplying nutrients to ruminant livestock is much greater using harvested feedstuffs as opposed to grazing pastures or crop residues. The primary function of a grassland farm is to convert solar energy to marketable livestock products in the most efficient manner. The fewer steps between the animal product and …


Tall Fescue Grazing Research, Glen Aiken Oct 2009

Tall Fescue Grazing Research, Glen Aiken

Kentucky Grazing Conference

‘Kentucky-31’ tall fescue, like it or hate it, covers 5 million acres of Kentucky and if you do not have it on your farm, it is likely that one of your bordering neighbors does! Tall fescue owes its persistence and productivity in large part to a fungal endophyte that infects most plants. This endophyte produces an array of alkaloids that benefit the plant in tolerating heat, drought, and grazing. Unfortunately, the endophyte also produces ergot alkaloids that can cause “fescue toxicosis” in cattle. Cattle inflicted with toxicosis have reduced dry matter intake, elevated body temperature, and often retain their winter …


Our Experiences With Eastern Gamagrass, Tommy R. Yankey Oct 2009

Our Experiences With Eastern Gamagrass, Tommy R. Yankey

Kentucky Grazing Conference

As livestock producers try to reduce their cost of production, many look at ways to reduce their feed costs. Feed costs have been identified as the largest single cost of livestock production, making up 50 to 70% of the total cost of production. Grazing is the cheapest way to feed cattle on a cost per pound of nutrient basis.


“Mangra”- Exploring The Organization Of An Environmental Education Curriculum In A Village Equipped For Sustainable Development, Abigail Phillips Oct 2009

“Mangra”- Exploring The Organization Of An Environmental Education Curriculum In A Village Equipped For Sustainable Development, Abigail Phillips

Independent Study Project (ISP) Collection

The rapid growth of urban centers in the last century has resulted in obvious social stratification and neglect of the natural environment. Not only is the gap between rich and poor increasing, but the resources that supply urban consumption and community development are increasingly depleted without due recognition. These issues are successfully addressed in some communities by drawing example from more traditional practices of ecological management, such as water conservation and local food production. Environmental education could be utilized to aid in the relief of social issues and environmental degradation if the curriculum is specialized for each community’s circumstance. Children …


Testing The Baobab’S Mettle: An Evaluation Of The Sustainability And Economic Potential Of Harvesting Adansonia Digitata, Benjamin Rhodes Oct 2009

Testing The Baobab’S Mettle: An Evaluation Of The Sustainability And Economic Potential Of Harvesting Adansonia Digitata, Benjamin Rhodes

Independent Study Project (ISP) Collection

In light of southern Africa’s growing population and economy, as well as the increasing international market for Adansonia digitata products, it seems important to ascertain whether or not rural baobab harvesting is having an impact on the health of the trees and whether it could be improved or expanded to increase benefits to communities. This study focused on 72 trees in and around the village of Gweta, Botswana, examining local usage and harvesting practices and exploring their correlations with the health of the trees. Results suggest that baobab harvesting in its current form is detrimental to the trees’ health and …


Survival And Productivity Of A Low-Density Black Bear Population In Rocky Mountain National Park, Colorado, Roger A. Baldwin, Louis C. Bender Oct 2009

Survival And Productivity Of A Low-Density Black Bear Population In Rocky Mountain National Park, Colorado, Roger A. Baldwin, Louis C. Bender

Human–Wildlife Interactions

Rocky Mountain National Park (RMNP) has supported a small black bear (Ursus americanus) population of low productivity. Increased visitor use of the park and development around its periphery could lead to a reduction in population viability of RMNP’s bear population or could increase the potential for human–bear conflict. Therefore, we investigated contemporary survival and productivity parameters for RMNP’s black bear population from 2003 to 2006 and compared these values to historic levels (1984–1991) and population means throughout the western United States to clarify the current status of RMNP’s bear population. The contemporary black bear population showed signs of …


Phenotopic Plasticity Of Leaf Shape Along A Temperature Gradient In Acer Rubrum, Dana L. Royer, Laura A. Meyerson, Kevin M. Robertson, Jonathan M. Adams Oct 2009

Phenotopic Plasticity Of Leaf Shape Along A Temperature Gradient In Acer Rubrum, Dana L. Royer, Laura A. Meyerson, Kevin M. Robertson, Jonathan M. Adams

Natural Resources Science Faculty Publications

Both phenotypic plasticity and genetic determination can be important for understanding how plants respond to environmental change. However, little is known about the plastic response of leaf teeth and leaf dissection to temperature. This gap is critical because these leaf traits are commonly used to reconstruct paleoclimate from fossils, and such studies tacitly assume that traits measured from fossils reflect the environment at the time of their deposition, even during periods of rapid climate change. We measured leaf size and shape in Acer rubrum derived from four seed sources with a broad temperature range and grown for two years in …