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Voluntary Exercise In Phosphorylase Kinase Deficient Mice, Ashley M. Mefford 2010 Western Kentucky University

Voluntary Exercise In Phosphorylase Kinase Deficient Mice, Ashley M. Mefford

Honors College Capstone Experience/Thesis Projects

Phosphorylase kinase (PhK), a key regulator of glycogenolysis, is critical for maintaining blood glucose levels thus providing energy to sustain muscle contraction. A deficiency of PhK in skeletal muscle is the cause of one type of glycogen storage disease (GSD) in humans. This study investigates the physiological and genetic adaptations that occur in a mouse model of GSD, I/LnJ mice, in response to voluntary exercise. Juvenile (6-8 weeks old) and adult (12-14 weeks old) I/LnJ and wild-type C57/Bl6 mice exercised voluntarily for 1, 2 or 5 weeks. Exercise data was calculated as mean daily running time, daily ...


Slowing And Switching Of Light In Semiconductor Quantum Wells, Murat Yildirim 2010 University of Iowa

Slowing And Switching Of Light In Semiconductor Quantum Wells, Murat Yildirim

Theses and Dissertations

After light became a part of the telecommunication system, the manipulation of light, especially the control of the speed of light, became a focus of research. By using the different approaches of the interaction between light and matter, there have been many successful attempts to slow down the speed of light, even to several meters per second. In the first part of my thesis, I studied pulse propagation in absorptive media (GaAs/AlGaAs multiple quantum well structures-MQWs) to gain insight into the linear interaction between matter and light. Systematic and fundamental measurements of pulse propagation in GaAs/AlGaAs multiple quantum ...


Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein 2010 Old Dominion University

Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein

Physics Faculty Publications

We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations ...


Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani 2010 Old Dominion University

Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani

Physics Faculty Publications

We present a study of high energy photodisintegration of proton-pairs through the γ + 3He → p + p + n channel. Photon energies, , from 0.8 to 4.7 GeV were used in kinematics corresponding to a proton pair with high relative momentum and a neutron nearly at rest. The s−11 scaling of the cross section, as predicted by the constituent counting rule for two nucleon photodisintegration, was observed for the first time. The onset of the scaling is at a higher energy and the cross section is significantly lower than for deuteron (pn pair) photodisintegration. For below the ...


Molecular Mechanics Studies Of Enzyme Evolutionary Mechanisms, Manoj Singh 2010 Clemson University

Molecular Mechanics Studies Of Enzyme Evolutionary Mechanisms, Manoj Singh

All Dissertations

In the current dissertation, closely related studies to quantify the mechanism underlying enzyme evolution have been discussed. The HIV-1 protease and beta-lactamase enzymes were used as model systems for these studies. These are well known enzymes that are associated with drug resistance and are associated with the pathogenic diseases, and therefore, developing molecular level understanding of drug resistance through these enzymes has fundamental as well as practical importance.
In chapter 2, the relationship between errors in modeled protein structures and associated binding affinity predictions to small molecules is established. The results of this study are applicable in addressing a wide ...


Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige 2010 Old Dominion University

Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige

OEAS Faculty Publications

Development of repeatable and quantitative tools are necessary for determining the abundance and distribution of different types of benthic habitats, detecting changes to these ecosystems, and determining their role in the global carbon cycle. Here we used ocean color remote sensing techniques to map different major groups of primary producers and estimate net primary productivity (NPP) across Great Bahama Bank (GBB). Field investigations on the northern portion of the GBB in 2004 revealed 3 dominant types of benthic primary producers: seagrass, benthic macroalgae, and microalgae attached to sediment. Laboratory measurements of NPP ranged from barely net autotrophic for grapestone sediment ...


A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. DiTullio 2010 Old Dominion University

A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio

OEAS Faculty Publications

We report the distribution of cobalt (Co) in the Ross Sea polynya during austral summer 2005-2006 and the following austral spring 2006. The vertical distribution of total dissolved Co (dCo) was similar to soluble reactive phosphate (PO(4)(3-)), with dCo and PO(4)(3-) showing a significant correlation throughout the water column (r(2) = 0.87, 164 samples). A strong seasonal signal for dCo was observed, with most spring samples having concentrations ranging from similar to ~ 45-85 pM, whereas summer dCo values were depleted below these levels by biological activity. Surface transect data from the summer cruise revealed concentrations ...


Determination Of Total Dissolved Cobalt In Uv-Irradiated Seawater Using Flow Injection With Chemiluminescence Detection, Rachel U. Shelley, Bernhard Zachhuber, Peter N. Sedwick, Paul J. Worsfold, Maeve C. Lohan 2010 Old Dominion University

Determination Of Total Dissolved Cobalt In Uv-Irradiated Seawater Using Flow Injection With Chemiluminescence Detection, Rachel U. Shelley, Bernhard Zachhuber, Peter N. Sedwick, Paul J. Worsfold, Maeve C. Lohan

OEAS Faculty Publications

A sensitive flow-injection method with chemiluminescence detection (FI-CL) for the determination of dissolved cobalt in open ocean samples, suitable for shipboard use has been developed. To date, FI methods for dissolved cobalt have been used only in coastal and estuarine waters. Therefore, significant modifications to existing methods were required, including (1) the use of a commercially available iminodiacetate (IDA) resin (Toyopearl AF-chelate 650M) in place of resin immobilized 8-hydroxyquinoline for online preconcentration and matrix removal, (2) the introduction of acidified ammonium acetate (pH 4) as a column-conditioning step before sample loading and rinse steps, and most importantly, (3) UV irradiation ...


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 2010 Old Dominion University

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

OEAS 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 anticyclone (92 +/- 19 and 561 ...


Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman 2010 Old Dominion University

Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman

OEAS Faculty Publications

The diffuse attenuation coefficient Kᵈ is critical to understand the vertical distribution of underwater downwelling irradiance (Eᵈ). Theoretically Eᵈ is composed of the direct solar beam and the diffuse sky irradiance. Applying the statistical results from Hydrolight radiative transfer simulations, Kᵈ is expressed into a mathematical equation (named as PZ06) integrated from the contribution of direct solar beam and diffuse sky irradiance with the knowledge of sky and water conditions. The percent root mean square errors (RMSE) for the vertical distribution of Eᵈ(z) under various sky and water conditions between PZ06 and Hydrolight results are typically less than 4 ...


The Widespread Occurrence Of Coupled Carbonate Dissolution/Reprecipitation In Surface Sediments On The Bahamas Bank, David J. Burdige, Xinping Hu, Richard C. Zimmerman 2010 Old Dominion University

The Widespread Occurrence Of Coupled Carbonate Dissolution/Reprecipitation In Surface Sediments On The Bahamas Bank, David J. Burdige, Xinping Hu, Richard C. Zimmerman

OEAS Faculty Publications

Using two complimentary approaches (pore water advection/diffusion/reaction modeling and stable isotope mass balance calculations) we show that carbonate dissolution/reprecipitation occurs on early diagenetic time scales across a broad range of sediments on the Great Bahamas Bank. The input of oxygen into the sediments, which strongly controls sediment carbonate dissolution, has two major sources belowground input by seagrasses (that is, seagrass O2 pumping), and permeability-driven advective pore water exchange. The relative importance of these O2 delivery mechanisms depends on both seagrass density, and on how bottom water flow interacts with the seagrass canopy and leads to ...


Provenance Of The Stone Pavers In Christ Church, Lancaster Co., Virginia, Marcus M. Key, Jr., Robert J. Teagle, Treleven Haysom 2010 Dickinson College

Provenance Of The Stone Pavers In Christ Church, Lancaster Co., Virginia, Marcus M. Key, Jr., Robert J. Teagle, Treleven Haysom

Faculty and Staff Publications By Year

The goal of this paper is to determine the provenance of the stone pavers in the floor of Christ Church in Lancaster County. The church, finished in 1735, has cross-shaped aisles paved with fossiliferous limestone blocks. The geology of Virginia eliminates any potential local source for the stones. Historical documents suggest an English source. The distinctive clam and oyster fossils exposed in the stone pavers of the church allowed identification of the source rock: the Intermarine Member of the Durlston Formation of the Purbeck Limestone Group. These limestones are of Early Cretaceous age and outcrop along the Dorset coast of ...


Effect Of The Heterotrophic Dinoflagellate Oxyrrhis Marina And The Copepod Acartia Tonsa On Vertical Carbon Flux In And Around Thin Layers Of The Phytoflagellate Isochrysis Galbana, A. B. Bochdansky, S. M. Bollens, G. C. Rollwagen-Bollens, A. H. Gibson 2010 Old Dominion University

Effect Of The Heterotrophic Dinoflagellate Oxyrrhis Marina And The Copepod Acartia Tonsa On Vertical Carbon Flux In And Around Thin Layers Of The Phytoflagellate Isochrysis Galbana, A. B. Bochdansky, S. M. Bollens, G. C. Rollwagen-Bollens, A. H. Gibson

OEAS Faculty Publications

Dynamics of material and energy flow through food webs differ when resources are allocated in patches in comparison to situations in which the same resources are distributed evenly throughout the water column. Thin layers of plankton are special cases of such resource patches. While previous studies have predominantly focused on the response of organisms to these layers, we investigated how 2 types of grazers in turn affect thin layers. In an experimental study with tightly controlled environmental conditions, we monitored the redistribution of particulate organic (POC), dissolved organic (DOC) and inorganic (DIC) carbon from thin layers of Isochrysis galbana. The ...


Turbulent Mixing In A Strongly Forced Salt Wedge Estuary, David K. Ralston, W. Rockwell Geyer, James A. Lerczak, Malcolm Scully 2010 Old Dominion University

Turbulent Mixing In A Strongly Forced Salt Wedge Estuary, David K. Ralston, W. Rockwell Geyer, James A. Lerczak, Malcolm Scully

OEAS Faculty Publications

Turbulent mixing of salt is examined in a shallow salt wedge estuary with strong fluvial and tidal forcing. A numerical model of the Merrimack River estuary is used to quantify turbulent stress, shear production, and buoyancy flux. Little mixing occurs during flood tides despite strong velocities because bottom boundary layer turbulence is dislocated from stratification elevated in the water column. During ebbs, bottom salinity fronts form at a series of bathymetric transitions. At the fronts, near-bottom velocity and shear stress are low, but shear, stress, and buoyancy flux are elevated at the pycnocline. Internal shear layers provide the dominant source ...


Virginia Game Fish Tagging Program Annual Report 2009, John A. Lucy, Lewis Gillingham 2010 Virginia Institute of Marine Science

Virginia Game Fish Tagging Program Annual Report 2009, John A. Lucy, Lewis Gillingham

Reports

Through 2009, the Virginia Game Fish Tagging Program has maintained a 15-year database for tagged and recaptured fish. The program is a cooperative project of the Virginia Saltwater Fishing Tournament (under the Virginia Marine Resources Commission/VMRC) and the Virginia Institute of Marine Science (VIMS) of the College of William and Mary (under VIMS Sea Grant Marine Extension Program).


Center For Coastal Resources Management Annual Report 2010, Center for Coastal Resources Management, Virginia Institute of Marine Science 2010 William & Mary

Center For Coastal Resources Management Annual Report 2010, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

No abstract provided.


Summary Tables: Fairfax County And The City Of Alexandria, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl H. Herschner, Karinna Nunez, Karen Reay, Tamia Rudnicky 2010 Virginia Institute of Marine Science

Summary Tables: Fairfax County And The City Of Alexandria, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl H. Herschner, Karinna Nunez, Karen Reay, Tamia Rudnicky

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).


Closed Time-Like Curves And Inertial Frame Dragging: How To Time Travel Via Spacetime Rotation, Conrad Wilson Moore 2010 Bucknell University

Closed Time-Like Curves And Inertial Frame Dragging: How To Time Travel Via Spacetime Rotation, Conrad Wilson Moore

Honors Theses

As the number of solutions to the Einstein equations with realistic matter sources that admit closed time-like curves (CTC's) has grown drastically, it has provoked some authors [10] to call for a physical interpretation of these seemingly exotic curves that could possibly allow for causality violations. A first step in drafting a physical interpretation would be to understand how CTC's are created because the recent work of [16] has suggested that, to follow a CTC, observers must counter-rotate with the rotating matter, contrary to the currently accepted explanation that it is due to inertial frame dragging that CTC ...


Shallow Water Dredging, Center for Coastal Resources Management, Virginia Institute of Marine Science 2010 William & Mary

Shallow Water Dredging, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay


A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N.E. Spaulding, D.A. Meese, I. Baker, P.A. Mayewski 2010 University of Maine

A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N.E. Spaulding, D.A. Meese, I. Baker, P.A. Mayewski

Open Dartmouth: Peer-reviewed articles by Dartmouth faculty

Firn microstructure is accurately characterized using images obtained from scanning electron microscopy (SEM). Visibly etched grain boundaries within images are used to create a skeleton outline of the microstructure. A pixel-counting utility is applied to the outline to determine grain area. Firn grain sizes calculated using the technique described here are compared to those calculated using the techniques of Gow (1969) and Gay and Weiss (1999) on samples of the same material, and are found to be substantially smaller. The differences in grain size between the techniques are attributed to sampling deficiencies (e.g. the inclusion of pore filler in ...


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