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2006

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Regulation Of Apoptotic Alkalinization Through Phosphorylation Of Sodium Hydrogen Exchanger Via P38 Mitogen Activated Protein Kinase, Amy Greinier Jan 2006

Regulation Of Apoptotic Alkalinization Through Phosphorylation Of Sodium Hydrogen Exchanger Via P38 Mitogen Activated Protein Kinase, Amy Greinier

Electronic Theses and Dissertations

Regulation of intracellular pH is responsible for many cellular processes, such as metabolism, cell cycle progression, and apoptosis. Many chemotherapeutic agents work by inducing target cells to undergo apoptosis, a cell death process still poorly understood. Previous studies demonstrated that a rise in intracellular pH activated apoptotic proteins leading to cytochrome C release. This "apoptotic alkalinization" occurred upon activation of the plasma membrane protein, sodium hydrogen exchanger-1 (NHE1), whose activity is regulated by the stress kinase p38 MAPK. In previous studies, upon cytokine withdrawal from cytokine-dependent lymphocytes induced the activity of the p38 MAP kinase which then phosphorylated the C-terminus …

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On Modeling Hiv Infection Of Cd4+ T Cells, Amy Comerford Jan 2006

On Modeling Hiv Infection Of Cd4+ T Cells, Amy Comerford

Electronic Theses and Dissertations

We examine an early model for the interaction of HIV with CD4+ T cells in vivo and define possible parameters and effects of said parameters on the model. We then examine a newer, more simplified model for the interaction of HIV with CD4+ T cells that also considers four populations: uninfected T cells, latently infected T cells, actively infected T cells, and free virus. The stability of both the disease free steady state and the endemically infected steady state are examined utilizing standard methods and the Routh-Hurwitz criteria. We show that if N, the number of infectious virions produced per …

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Predation On The Eastern Oyster Crassostrea Virginica On Intertidal Reefs Affected By Recreational Boating, Jennifer Stiner Jan 2006

Predation On The Eastern Oyster Crassostrea Virginica On Intertidal Reefs Affected By Recreational Boating, Jennifer Stiner

Electronic Theses and Dissertations

Widely regarded as a keystone species and ecosystem engineer, the eastern oyster Crassostrea virginica plays a vital role in estuarine environments. Complex, three-dimensional oyster reefs act as havens for biodiversity and contribute to ecological processes. Recently, concern for this resource has arisen in Mosquito Lagoon, Florida, the southernmost limit along the Atlantic coast for undisturbed, intertidal reefs of C. virginica. Since the 1990s, intense recreational boating activity has caused atypical dead margins (mounds of disarticulated shells) to emerge on the seaward edges of oyster reefs located along major navigational channels. Once dead margins are formed, little is known about their …

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Reproductive Delay In The Female Cape Ground Squirrel (Xerus Inauris), Beth Pettitt Jan 2006

Reproductive Delay In The Female Cape Ground Squirrel (Xerus Inauris), Beth Pettitt

Electronic Theses and Dissertations

The Cape ground squirrel, Xerus inauris, is a highly social cooperative breeder that forms groups containing multiple breeding females. While the distribution of reproduction among group members is fairly even (i.e. exhibits low reproductive skew), previous studies of Cape ground squirrels suggest the reproductive development of sub-adult females is inhibited by the presence of adult breeding female group mates. As reproductive delay is known to be influenced by a number of different parameters, my goal was to determine if other factors affected the timing of sexual maturity, and if so, which factors are the most influential. In this study, I …

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Expression And Characterization Of Mycobacterium Paratuberculosis 19kda With Posttranslational Modification, Mitra Safavi-Khasraghi Jan 2006

Expression And Characterization Of Mycobacterium Paratuberculosis 19kda With Posttranslational Modification, Mitra Safavi-Khasraghi

Electronic Theses and Dissertations

Despite the fact that E. coli supports limited posttranslational modification, this bacterium has been universally used as the expression system of choice. Expression of modified proteins in E. coli may lead to expression of recombinant proteins that lack essential immunomodulatory or catalytic components essentials for infectious processes. Previously in our laboratory, pMptb#28 plasmid containing a 4.8 kb insert from M. paratuberculosis has been identified which expressed 16 kDa recombinant protein in E. coli and 19 kDa recombinant protein in Mycobacterium smegmatis. The objective of this study is to identify the ORF sequence, investigate possible posttranslational modification and characterize the protein …

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Silent Outsiders: Searching For Queer Identity In Composition Readers, Travis Duncan Jan 2006

Silent Outsiders: Searching For Queer Identity In Composition Readers, Travis Duncan

Electronic Theses and Dissertations

This study searches twenty composition readers' table of contents for the degree of inclusivity of queer people and issues. Four means of erasure are labeled as possible erasing of queer identity: presuming heteronormativity, overt homophobia, perpetuating tokenism, and pathologizing queer identity. The presence of other differences are compared to the number of times that queer identity is referenced in the table of contents. The final portion of the analysis examines the two most inclusive composition readers to understand more clearly how the readers present queer individuals and issues. In a sense, I want to explore the question of how often …

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Monitoring A Potentially Stressful Situation In Captive Western Lowland Gorillas (Gorilla Gorilla Gorilla) Through Analysis Of Behavior And Urinary Cortisol, Douglas Skurski Jan 2006

Monitoring A Potentially Stressful Situation In Captive Western Lowland Gorillas (Gorilla Gorilla Gorilla) Through Analysis Of Behavior And Urinary Cortisol, Douglas Skurski

Electronic Theses and Dissertations

The concept of quantifying animal welfare has received much discussion, in various industries such as agriculture, laboratory, and zoological facilities. Behavioral, physical, and physiological indicators of welfare have previously been used to assess animal welfare; each having advantages and disadvantages, ranging from the practicality of data collection, to the validity of the data and how it is interpreted. Concurrent assessment of multiple measures is a more robust way to examine animal welfare, which utilizes the advantages of each measure, and provides additional information on which to base conclusions and animal care management decisions. This study used measures of behavior and …

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When Your Income Drops, Liz Gorham Jan 2006

When Your Income Drops, Liz Gorham

SDSU Extension Fact Sheets

Income loss is traumatic, whether it’s your entire family income or a second income and no matter how it happens—a bad year in your business or farm/ranch operation, company layoffs, downsizing, divorce, illness, or death. Take heart; there are immediate and positive steps to take. You can get back on top. Right now you need to cut back on spending and develop a spending plan to help you pay your bills. If your income will be affected for more than a month, adjust your spending habits to maintain control of family finances over an extended period of time. Financial affairs …

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Wsuls 2006 Annual Report, Wayne State University Library System Jan 2006

Wsuls 2006 Annual Report, Wayne State University Library System

Library Publications

2006 Annual Report includes: Message from the Dean; IMLS Grant to Recruit 21st Century Librarians; Library System Expands Open Access to Scholarly Communications; LISP Moves Up in Grad School Rankings; LISP Recognized for Excellence in Distance Education; LIS Faculty Judith J. Field Honored with John Cotton Dana Award; LISP Hosts Kuwaiti Professor; LISP Names 2006 Distinguished Alumna and Distinguished Professional; DALNET Makes VA Archives Available to Public; The First-Ever National Rock & Roll Library Tour Featuring the High Strung; Legal Writing and Research Modules; WSULS Digital Collection Comes to Life in Detroit Historical Museum Exhibition; First-Year Experience Web Page; Michigan …

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Dairy Digest 2006, South Dakota State University Dairy Club Jan 2006

Dairy Digest 2006, South Dakota State University Dairy Club

Dairy Digest

No abstract provided.

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Cold Stress And Newborn Calves, Lanette Butler, Russ Daly, Cody Wright Jan 2006

Cold Stress And Newborn Calves, Lanette Butler, Russ Daly, Cody Wright

SDSU Extension Extra Archives

Calf survival in northern climates can be a challenge. Death losses after birth may be due to one or more of several factors including infectious agents, dystocia, genetic abnormalities, and environmental stress.2 Cow nutrition also influences calf survivability2,3,7 as well as the timing and type of colostrum intake.8 These factors, whether singular events or in combination, dramatically impact calf survival.

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Determining The Value Of Drought-Stressed Corn, E. Kim Cassel, Lester R. Vough, Stanley W. Fultz Jan 2006

Determining The Value Of Drought-Stressed Corn, E. Kim Cassel, Lester R. Vough, Stanley W. Fultz

SDSU Extension Extra Archives

Drought-stressed corn for grain or silage does not automatically signal disaster, as both crops can provide high-quality forage for ruminant animals. Drought-stressed corn or corn that is unpollinated will produce little or no grain crop for the crop farmer to sell, but dairy producers can use the unpollinated corn for silage. On a dry matter basis, the drought-stressed corn will be approximately equal in feeding value to normal corn silage.

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Distillers Grains For Dairy Cattle, D. J. Schingoethe, K. F. Kalscheur, A. D. Garcia Jan 2006

Distillers Grains For Dairy Cattle, D. J. Schingoethe, K. F. Kalscheur, A. D. Garcia

SDSU Extension Extra Archives

Feeding distillers grains is nothing new; such products have been fed to cattle for more than a century. What is new, however, are the many ethanol plants now in the upper Midwest and the increased interest in feeding their co-product, distillers grains. This report is an overview of the nutritional value of distillers grains and gives some guidelines for feeding.

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Acute Interstitial Pneumonia (Aip)* In Range Cattle, Cooperative Extension Service Jan 2006

Acute Interstitial Pneumonia (Aip)* In Range Cattle, Cooperative Extension Service

SDSU Extension Extra Archives

AIP is an acute respiratory disease of range cattle that occurs following movement from poor pasture to lush pasture/forage. Yearlings are less susceptible than mature cows, and calves are almost never affected. It appears that sheep (and horses) are not susceptible or are much less susceptible to AIP. The disease occurs within 10 days of movement to improved forage. Pastures of any sort (grass or legume) as well as annual crops (corn, sudan grass, etc.) can support AIP. AIP also can be seen when animals preferentially graze lush growth in lowland meadows or water discharge areas, even if the remainder …

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Fuel Savings: Family Transportation, Donna Bittiker, Liz Gorham, Dick Nicolai Jan 2006

Fuel Savings: Family Transportation, Donna Bittiker, Liz Gorham, Dick Nicolai

SDSU Extension Extra Archives

It costs to drive, yet how we love it. We can cut transportation costs. We can improve vehicle maintenance, use some wise practices, make smart purchases, and modify how we operate our vehicles.

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Fuel Savings: Farm/Ranch Enterprise, Dick Nicolai, Liz Gorham, Donna Bittiker Jan 2006

Fuel Savings: Farm/Ranch Enterprise, Dick Nicolai, Liz Gorham, Donna Bittiker

SDSU Extension Extra Archives

Gasoline and diesel fuel prices have increased over a dollar during the past year. Even a small amount of fuel savings can have an impact on operating expenses for a farm or ranch. Consider changes in practices, modifying operations, improving maintenance, and buying wisely.

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2006 South Dakota Beef Report, Department Of Animal And Range Sciences, South Dakota State University, Agricultural Experiment Station, South Dakota State University, Cooperative Extension Service, South Dakota State University Jan 2006

2006 South Dakota Beef Report, Department Of Animal And Range Sciences, South Dakota State University, Agricultural Experiment Station, South Dakota State University, Cooperative Extension Service, South Dakota State University

South Dakota Beef Report, 2006

This is the 2006 South Dakota Beef Report. The articles published in this report summarize many of the beef cattle research activities conducted at South Dakota State University during 2006. The articles in this report have many levels of application. Some information has immediate application for your farm, ranch, or agribusiness. The articles include information on nutrition, feed management, reproductive management, health, growth and development, and economics of the cattle and beef industry in South Dakota.

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Vital Signs Monitoring In Our Parks: What To Measure?, Nels H. Troelstrup Jr., Jill Rust Jan 2006

Vital Signs Monitoring In Our Parks: What To Measure?, Nels H. Troelstrup Jr., Jill Rust

Oak Lake Field Station Research Publications

The National Park Service (NPS) Inventory and Monitoring program seeks to define vital signs for the purpose of monitoring and managing park conditions throughout the United States. Aquatic macroinvertebrate biotic integrity ranks high as one potential vital sign of interest to park staff and partnering agencies. The objective of this effort was to identify discriminating measures of invertebrate community structure which might be used to monitor aquatic biotic integrity. Invertebrate sweepnet samples were collected from 58 large river, stream, spring and bison watering hole habitats during the summers of 2004 and 2005. Invertebrate counts were used to calculate 68 metrics …

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Spectrophotometric Analysis Of The Cyanide Metabolite 2-Aminothiazoline-4-Carboxylic Acid (Atca), Steven I. Baskin, Ilona Petrikovics, Gennady E. Platoff, Gary A. Rockwood, Brian A. Logue Jan 2006

Spectrophotometric Analysis Of The Cyanide Metabolite 2-Aminothiazoline-4-Carboxylic Acid (Atca), Steven I. Baskin, Ilona Petrikovics, Gennady E. Platoff, Gary A. Rockwood, Brian A. Logue

Chemistry and Biochemistry Faculty Publications

Methods of directly evaluating cyanide levels are limited by the volatility of cyanide and by the difficulty of establishing steady-state cyanide levels with time. We investigated the measurement of a stable, toxic metabolite, 2-aminothiazoline-4-carboxylic acid (ATCA), in an attempt to circumvent the challenge of directly determining cyanide concentrations in aqueous media. This study was focused on the spectrophotometric ATCA determination in the presence of cyanide, thiocyanate (SCN−), cysteine, rhodanese, thiosulfate, and other sulfur donors. The method involves a thiazolidine ring opening in the presence of p-(hydroxy-mercuri)-benzoate, followed by the reaction with diphenylthiocarbazone (dithizone). The product is spectrophotometrically analyzed at 625 …

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Constraining Bubble Dynamics And Mixing With Dissolved Gases: Implications For Productivity Measurements By Oxygen Mass Balance, Roberta C. Hamme, Steven R. Emerson Jan 2006

Constraining Bubble Dynamics And Mixing With Dissolved Gases: Implications For Productivity Measurements By Oxygen Mass Balance, Roberta C. Hamme, Steven R. Emerson

Journal of Marine Research

We used a dynamic mixed layer model to determine carbon export by the oxygen mass balance method from a time series of O2/Ar, N2/Ar and Ne measurements collected at station ALOHA near Hawaii from July 2000 to June 2001. The inert gas measurements constrain the flux of oxygen into the mixed layer from small, collapsing bubbles (injection) to be greater than or equal to the flux from larger bubbles (exchange), with mean estimates of the ratio in the range of 1–2. We also show that monthly observations of temperature and inert gases cannot constrain the rate …

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Generalized Inversion Of The Gent-Cane Model Of The Tropical Pacific With Tropical Atmosphere-Ocean (Tao) Data, A. F. Bennett, B. S. Chua, H. E. Ngodock, D. E. Harrison, M. J. Mcphaden Jan 2006

Generalized Inversion Of The Gent-Cane Model Of The Tropical Pacific With Tropical Atmosphere-Ocean (Tao) Data, A. F. Bennett, B. S. Chua, H. E. Ngodock, D. E. Harrison, M. J. Mcphaden

Journal of Marine Research

We here describe the results of our latest effort to reanalyze TAO monthly mean surface and subsurface temperature observations constrained by a tropical Pacific ocean model, and simultaneously to evaluate the physical consistency of the observations and the model. Both tasks are executed by weak–constraint, four–dimensional variational assimilation of the observations into the model. In this study our reanalysis employs the reduced–gravity Gent–Cane model, combined with the 'KPP–interior' parameterization of vertical turbulent fluxes. With the limited vertical resolution adopted in previous studies of this model, the 'W4DVAR' or inverse method fails to produce an acceptable reanalysis, as the dynamical residuals …

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Shear And Turbulence Production Across Subtidal Channels, David K. Ralston, Mark T. Stacey Jan 2006

Shear And Turbulence Production Across Subtidal Channels, David K. Ralston, Mark T. Stacey

Journal of Marine Research

In intertidal regions with subtidal channels, effects of bathymetry on overlying flow vary greatly with tidal stage. Around low water when mudflats and marsh are exposed, flow is constrained to channels, but when water depths are greater, tidal forcing may not necessarily be aligned with meandering channel axes. Flow across the channel can generate strong shear and turbulence at the elevation of the channel banks and can significantly increase turbulent energy in the middle of the water column. Field observations in a mudflat channel of San Francisco Bay indicate that cross-channel shear regularly occurs there early in ebb tides. With …

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Physical-Biological Interactions And Their Effect On Phytoplankton Blooms In Fjords And Near-Coastal Waters, Lars Erik Holmedal, Torbjørn Utnes Jan 2006

Physical-Biological Interactions And Their Effect On Phytoplankton Blooms In Fjords And Near-Coastal Waters, Lars Erik Holmedal, Torbjørn Utnes

Journal of Marine Research

A one-dimensional flow model which accounts for turbulence and stratification in the upper ocean has been applied in conjunction with a one-dimensional production-advection-diffusion model to predict the initial evolution of the phytoplankton biomass concentration under given biological and physical conditions. Here the stratification is caused by the salinity which is modeled by a one-dimensional diffusion equation; the density is related to the salinity by a linear relation (state equation). The resulting one-dimensional model has been applied to investigate how local physical conditions affect the initiation of phytoplankton blooms in nutrition rich waters characterized by wind driven currents and salinity stratification. …

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An Estuarine Box Model Of Freshwater Delivery To The Coastal Ocean For Use In Climate Models, Richard W. Garvine, Michael M. Whitney Jan 2006

An Estuarine Box Model Of Freshwater Delivery To The Coastal Ocean For Use In Climate Models, Richard W. Garvine, Michael M. Whitney

Journal of Marine Research

Present day climate models employ a coarse horizontal grid that is unable to fully resolve estuaries or continental shelves. The importation of fresh water from rivers is critical to the state of deep ocean stratification, but currently the processing of that fresh water as it passes from the river through the estuary and adjacent shelf is not represented in the coastal boundary conditions of climate models. An efficient way to represent this input of fresh water to the deep ocean would be to treat the estuary and shelf domains as two coupled box models with river water input to the …

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On The Mechanism Of Centennial Thermohaline Oscillations, Florian Sévellec, Thierry Huck, Mahdi Ben Jelloul Jan 2006

On The Mechanism Of Centennial Thermohaline Oscillations, Florian Sévellec, Thierry Huck, Mahdi Ben Jelloul

Journal of Marine Research

Centennial oscillations of the ocean thermohaline circulation are studied in a 2-D latitude-depth model under mixed boundary conditions (i.e. restoring surface temperature and prescribed freshwater flux). The oscillations are revealed through linear stability analysis of a steady state obtained in a single hemisphere configuration. A density variance budget is performed and helps determine the physical processes sustaining these oscillations: the restoring surface temperature appears as a source of density variance – this is a consequence of positively-correlated temperature and salinity anomalies. A minimal model, the Howard-Malkus loop oscillator, enables us to understand physically the oscillatory and growth mechanisms. The centennial …

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Analysis Of Instabilities And Mesoscale Motion In A Terrain-Following Coordinate Ocean Model, Ingerid Fossum, Lars Petter Røed Jan 2006

Analysis Of Instabilities And Mesoscale Motion In A Terrain-Following Coordinate Ocean Model, Ingerid Fossum, Lars Petter Røed

Journal of Marine Research

We perform a combined potential vorticity analysis and energy analysis to analyze instabilities and mesoscale motion in a continuously stratified, terrain-following coordinate ocean model. Care is exercised to ensure that the potential vorticity is conserved along isopycnals in the absence of sources and sinks. We also derive expressions for the energy components and the associated conversion terms suitable for a terrain-following coordinate ocean model. To demonstrate the usefulness of the new combined analysis tool for detection of instabilities, we analyze results from a numerical model experiment in which the ocean model is contained in a long, rectangular channel closed at …

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Carbon Flows Through A Benthic Food Web: Integrating Biomass, Isotope And Tracer Data, Dick Van Oevelen, Karline Soetaert, Jack J. Middelburg, Peter M. J. Herman, Leon Moodley, Ilse Hamels, Tom Moens, Carlo H. R. Heip Jan 2006

Carbon Flows Through A Benthic Food Web: Integrating Biomass, Isotope And Tracer Data, Dick Van Oevelen, Karline Soetaert, Jack J. Middelburg, Peter M. J. Herman, Leon Moodley, Ilse Hamels, Tom Moens, Carlo H. R. Heip

Journal of Marine Research

The herbivorous, detrital and microbial pathways are major components of marine food webs. Although it is commonly recognized that these pathways can be linked in several ways, elucidating carbon transfers between or within these pathways remains a challenge. Intertidal flat communities are driven by a wide spectrum of organic matter sources that support these different pathways within the food web. Here we reconstruct carbon pathways using inverse analysis based on mass balancing, stable isotope signatures and tracer data. Data were available on biomass, total carbon production and processing, integrated diet information from stable isotope signatures and the transfer of recently …

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Tidal Fronts And Their Role In Air-Sea Gas Exchange, B. Baschek, D. M. Farmer, C. Garrett Jan 2006

Tidal Fronts And Their Role In Air-Sea Gas Exchange, B. Baschek, D. M. Farmer, C. Garrett

Journal of Marine Research

Tidal fronts are a common feature of many coastal environments. They are characterized by a surface convergence zone that enhances wave breaking and the generation of gas bubbles due to wave-current interaction. The associated downwelling currents carry bubbles to depths of up to 160 m and increase the amount of air that dissolves from them.An energetic tidal front is formed at the entrance to the Strait of Georgia, BC, Canada, by a hydraulically controlled sill flow with vertical velocities of up to 0.75 m s−1. Extensive ship-board measurements during two cruises are interpreted with models of wave-current interaction …

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Variation Beneath The Surface: Quantifying Complex Thermal Environments On Coral Reefs In The Caribbean, Bahamas And Florida, James J. Leichter, Brian Helmuth, Andrew M. Fischer Jan 2006

Variation Beneath The Surface: Quantifying Complex Thermal Environments On Coral Reefs In The Caribbean, Bahamas And Florida, James J. Leichter, Brian Helmuth, Andrew M. Fischer

Journal of Marine Research

Analysis of in situ temperature records collected on six coral reefs in the Caribbean, Bahamas, and Florida Keys reveal significant variability across a range of temporal and spatial scales from minutes to seasons, across depths, and among sites. Subsurface variability occurring at daily and faster frequencies is prevalent across the region, likely driven by combinations of diurnal heating and cooling, wind driven advection, and internal waves at tidal and faster frequencies. This high frequency variability is not detected in records of remotely-sensed sea surface temperature alone. Diurnal variability likely caused by diurnal solar heating and cooling and possibly by advection …

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A Model Of Methane Concentration Profiles In The Open Ocean, G. C. Nihous, S. M. Masutani Jan 2006

A Model Of Methane Concentration Profiles In The Open Ocean, G. C. Nihous, S. M. Masutani

Journal of Marine Research

Methane-bearing particulate matter formed in the upper ocean layer is allowed to settle and degrade, releasing methane into the water column as a source in one-dimensional advection-diffusion equations. Predicted carbon and methane particulate fluxes are in good agreement with sediment trap data, using parameters of expected magnitude and particulate methane production well within the mixed layer. This suggests a rapid pathway to the atmosphere and reduced effects on methane concentrations below. Vertical advection rates yielding a good fit between methane concentration calculations and data are larger than expected unless methane oxidation is included. This confirms the significance of methane oxidation …

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