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Sequence And Structural Analysis Of The Chitinase Insertion Domain Reveals Two Conserved Motifs Involved In Chitin Binding, Hai Li, Lesley H. Greene 2010 Old Dominion University

Sequence And Structural Analysis Of The Chitinase Insertion Domain Reveals Two Conserved Motifs Involved In Chitin Binding, Hai Li, Lesley H. Greene

Chemistry & Biochemistry Faculty Publications

Background: Chitinases are prevalent in life and are found in species including archaea, bacteria, fungi, plants, and animals. They break down chitin, which is the second most abundant carbohydrate in nature after cellulose. Hence, they are important for maintaining a balance between carbon and nitrogen trapped as insoluble chitin in biomass. Chitinases are classified into two families, 18 and 19 glycoside hydrolases. In addition to a catalytic domain, which is a triosephosphate isomerase barrel, many family 18 chitinases contain another module, i.e., chitinase insertion domain. While numerous studies focus on the biological role of the catalytic domain in chitinase ...


Koszul Duality For Multigraded Algebras, Fareed Hawwa 2010 Louisiana State University and Agricultural and Mechanical College

Koszul Duality For Multigraded Algebras, Fareed Hawwa

LSU Doctoral Dissertations

Classical Koszul duality sets up an adjoint pair of functors establishing an equivalence of categories. The equivalence is between the bounded derived category of complexes of graded modules over a graded algebra and the bounded derived category of complexes of graded modules over the quadratic dual graded algebra. This duality can be extended in many ways. We consider here two extensions: first we wish to allow a multigraded algebra, meaning that the algebra can be graded by any abelian group (not just the integers). Second, we will allow filtered algebras. In fact we are considering filtered quadratic algebras with an ...


Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, Ye Ai, Shizhi Qian, Sheng Liu, Sang W. Joo 2010 Old Dominion University

Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, Ye Ai, Shizhi Qian, Sheng Liu, Sang W. Joo

Mechanical & Aerospace Engineering Faculty Publications

Experiments show that particles smaller than the throat size of converging-diverging microchannels can sometimes be trapped near the throat. This critical phenomenon is associated with the negative dc dielectrophoresis arising from nonuniform electric fields in the microchannels. A finite-element model, accounting for the particle-fluid-electric field interactions, is employed to investigate the conditions for this dielectrophoretic (DEP) choking in a converging-diverging microchannel for the first time. It is shown quantitatively that the DEP choking occurs for high nonuniformity of electric fields, high ratio of particle size to throat size, and high ratio of particle's zeta potential to that of microchannel ...


Hyperbolic Geometry: A Guide To Models And Motion, Danielle J. Strieby 2010 University of Redlands

Hyperbolic Geometry: A Guide To Models And Motion, Danielle J. Strieby

Undergraduate Honors Theses

Twentieth century mathematics can be characterized by the study of functions. The most interesting functions are those that preserve the structure at hand. In many branches of mathematics transformations are looked at and classified. In geometry, transformations of a plane are very important. A transformation that distance is called an isometry. The classification of isometries is known in Euclidean geometry, and one will learn about each of them in any geometry course. Classification of isometries for the hyperbolic plane are not as well known, but they have been classified. In this paper we will discover hyperbolic geometry, investigate some of ...


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 ...


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 ...


On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church 2010 Old Dominion University

On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church

OEAS Faculty Publications

Paytan et al. (2009) argue that the atmospheric deposition of aerosols lead to copper concentrations that are potentially toxic to marine phytoplankton in a large area of tropical and subtropical North Atlantic Ocean. A key assumption in their model is that all marine aerosols (mineral dust and anthropogenic particles) have a high (40%) fractional solubility of copper. Our data show that the fractional solubility of copper for Saharan dust over the Sargasso Sea and Bermuda is significantly lower (1-7%). In contrast, anthropogenic aerosols with non-Saharan sources have significantly higher values (10-100%). Hence, the potential Cu toxicity in the tropical and ...


Impact Of Urban Runoff On Phosphorus, Nitrogen, And Dissolved Oxygen In A Shallow Subtropical Lake, Ryan Mesmer 2010 Louisiana State University and Agricultural and Mechanical College

Impact Of Urban Runoff On Phosphorus, Nitrogen, And Dissolved Oxygen In A Shallow Subtropical Lake, Ryan Mesmer

LSU Master's Theses

This research assessed the current conditions of water quality in a shallow subtropical lake, influenced by a highly developed urban environment. Specifically, the research focused on the dynamics of phosphorus, nitrogen, and dissolved oxygen, as well as the effects of stormwater runoff on lake water quality. Furthermore, the research quantified gross primary production, net primary production, and respiration in order to discern seasonal variation in lake metabolism. A water quality monitoring platform with multi-parameter probes was deployed in the center of University Lake on the Louisiana State University campus. A series of lake water quality parameters including dissolved oxygen (DO ...


Garden Of The Gods At Colorado Springs: Paleozoic And Mesozoic Sedimentation And Tectonics, Marcus R. Ross, William A. Hoesch, Steven A. Austin, John H. Whitmore, Timothy L. Clarey 2010 Liberty University

Garden Of The Gods At Colorado Springs: Paleozoic And Mesozoic Sedimentation And Tectonics, Marcus R. Ross, William A. Hoesch, Steven A. Austin, John H. Whitmore, Timothy L. Clarey

Faculty Publications and Presentations

Exposed along the southeast fl ank of the Colorado Front Range are rocks that beautifully illustrate the interplay of sedimentation and tectonics. Two major rangebounding faults, the Ute Pass fault and the Rampart Range fault, converge on the Garden of the Gods region west of Colorado Springs. Cambrian through Cretaceous strata upturned by these faults reveal in their grain compositions, textures, and bedforms radically different styles of sedimentation. The Cambrian/Ordovician marine transgressive deposits appear to have come to rest on a passive and tectonically inactive craton. In contrast, coarse-grained Pennsylvanian/Permian marine deposits of the Fountain Formation and Lyons ...


Ohio Conservation Plan: Plains Gartersnake, Thamnophis Radix, Norman Reichenbach, M. Barrie, K. Becka, G. Burghardt, S. Butterworth, C. Caldwell, F. Dierkes, P. Johantgen, K. Stanford, D. Wynn 2010 Liberty University

Ohio Conservation Plan: Plains Gartersnake, Thamnophis Radix, Norman Reichenbach, M. Barrie, K. Becka, G. Burghardt, S. Butterworth, C. Caldwell, F. Dierkes, P. Johantgen, K. Stanford, D. Wynn

Faculty Publications and Presentations

This plan outlines strategies and methods used in an ongoing study initiated in 1999 to restore a selfsustaining population of the Plains gartersnake (Thamnophis radix) in Ohio. Restoring a self-sustaining population would require increases in the current population to where the ratios of T. radix to T. sirtalis are approximately 1:1 in multiple locations in Killdeer Plains Wildlife Area (KPWA). This ratio would be similar to what was seen earlier by Reichenbach and Dalrymple (1986) at one site in KPWA.

The plan was developed by a team of enthusiastic conservationists representing, the Division of Wildlife (ODW), the Columbus and ...


Interionic Energy Transfer In Y3Al5O12: Ce3+, Pr3+ Phosphor, Lei Wang, Xia Zhang, Zhendong Hao, Yongshi Luo, Jiahua Zhang, Xiao-Jun Wang 2010 Chinese Academy of Sciences

Interionic Energy Transfer In Y3Al5O12: Ce3+, Pr3+ Phosphor, Lei Wang, Xia Zhang, Zhendong Hao, Yongshi Luo, Jiahua Zhang, Xiao-Jun Wang

Physics Faculty Publications

We present an investigation of dynamical processes of nonradiative energy transfer (ET)between Ce3+ and Pr3+ , and between Pr3+ ions in Y3Al5O12:Ce3+ , Pr3+ phosphor.Photoluminescence spectroscopy and fluorescence decay patterns are studied as a function ofPr3+ and Ce3+ concentrations. The analysis based on Inokuti–Hirayama model indicates that the ET from the lowest 5d state of Ce3+ to the D12 state of Pr3+ , and the quenching of theD12 state through a cross relaxation involving Pr3+ ions in the ground state are both governed by electric dipole–dipole interaction. An increase in the Ce3+–Pr3+ ET rate followed by the ...


K23au12sn9—An Intermetallic Compound Containing A Large Gold−Tin Cluster: Synthesis, Structure, And Bonding, Bin Li, Sung-Jin Kim, Gordon J. Miller, John D. Corbett 2010 Iowa State University

K23au12sn9—An Intermetallic Compound Containing A Large Gold−Tin Cluster: Synthesis, Structure, And Bonding, Bin Li, Sung-Jin Kim, Gordon J. Miller, John D. Corbett

Chemistry Publications

A polyanionic unit {Au12Sn9} with a novel “corrugated sheet” shape occurs in K23Au12Sn9. The compound was obtained by fusion of the pure elements in tantalum ampules at high temperatures followed by programmed cooling, and the structure was determined by X-ray diffraction: I4̅2m (No. 121), a = 20.834(3), c = 6.818(1) Å, Z = 2. The large heteroatomic cluster has D2d point symmetry and features a central four bonded (4b-) Sn, eight 3b- or 2b-Sn on the perimeter, and 24 linking nearly linear ...


Platinum And Palladium Complexes Containing Cationic Ligands As Catalysts For Arene Hid Exchange And Oxidation., J. Brannon Gary 2010 Stephen F Austin State University Department of Chemistry & Biochemistry

Platinum And Palladium Complexes Containing Cationic Ligands As Catalysts For Arene Hid Exchange And Oxidation., J. Brannon Gary

Faculty Publications

The direct functionalization of CH bonds has frequently been deemed a “Holy Grail” of organometallic chemistry.[1] A seminal example of this transformation was the demonstration by Shilov and co-workers that platinum(II) salts catalyze the direct oxidation of alkanes into their corresponding alcohols and alkyl halides.[2] Subsequent work in this area has focused on surveying diverse ligands for these reactions in an effort to enhance reactivity and selectivity, slow catalyst decomposition, and replace platinum(IV)-based oxidants with more cost-effective alternatives.[3–5] In a key development, chemists at Catalytica identified [bpymPtCl2] (bpym = bipyrimidine) as a pre-catalyst for ...


"Mechanistic And Computational Studies Of Oxidatively-Induced Aryl-Cf3 Bond Formation At Palladium, J. Brannon Gary 2010 Stephen F Austin State University Department of Chemistry & Biochemistry

"Mechanistic And Computational Studies Of Oxidatively-Induced Aryl-Cf3 Bond Formation At Palladium, J. Brannon Gary

Faculty Publications

This article describes the rational design of 1st generation systems for oxidatively-induced Aryl– CF3 bond-forming reductive elimination from PdII. Treatment of (dtbpy)PdII(Aryl)(CF3) (dtbpy = di-tert-butylbipyridine) with NFTPT (N-fluoro-1,3,5-trimethylpyridium triflate) afforded the isolable PdIV intermediate (dtbpy)PdIV(Aryl)(CF3)(F)(OTf). Thermolysis of this complex at 80 °C resulted in Aryl–CF3 bond-formation. Detailed experimental and computational mechanistic studies have been conducted to gain insights into the key reductive elimination step. Reductive elimination from this PdIV species proceeds via pre-equilibrium dissociation of TfO− followed by Aryl–CF3 coupling. DFT calculations reveal that the transition state for Aryl ...


Enrichment Of Echinacea Angustifolia With Bauer Alkylamide 11 And Bauer Ketone 23 Increased Anti-Inflammatory Potential Through Interference With Cox-2 Enzyme Activity, Carlie A. LaLone, Nan Huang, Ludmila Rizshsky, Man-Yu Yum, Navrozedeep Singh, Cathy Hauck, Basil J. Nikolau, Eve S. Wurtele, Marian L. Kohut, Patricia A. Murphy, Diane F. Birt 2010 Iowa State University

Enrichment Of Echinacea Angustifolia With Bauer Alkylamide 11 And Bauer Ketone 23 Increased Anti-Inflammatory Potential Through Interference With Cox-2 Enzyme Activity, Carlie A. Lalone, Nan Huang, Ludmila Rizshsky, Man-Yu Yum, Navrozedeep Singh, Cathy Hauck, Basil J. Nikolau, Eve S. Wurtele, Marian L. Kohut, Patricia A. Murphy, Diane F. Birt

Food Science and Human Nutrition Publications

Bauer alkylamide 11 and Bauer ketone 23 were previously found to be partially responsible forEchinacea angustifolia anti-inflammatory properties. This study further tested their importance using the inhibition of prostaglandin E2 (PGE2) and nitric oxide (NO) production by RAW264.7 mouse macrophages in the absence and presence of lipopolysaccharide (LPS) and E. angustifolia extracts, phytochemical enriched fractions, or pure synthesized standards. Molecular targets were probed using microarray, qRT-PCR, Western blot, and enzyme assays. Fractions with these phytochemicals were more potent inhibitors of LPS-induced PGE2 production than E. angustifolia extracts. Microarray did not detect changes in transcripts with ...


Submillimeter-Resolution Radiography Of Shielded Structures With Laser-Accelerated Electron Beams, Viswanathan Ramanathan, Sudeep Banerjee, Nathan D. Powers, Nathaniel Cunningham, Nathan A. Chandler-Smith, Kun Zhao, Kevin Brown, Donald Umstadter, Shaun Clarke, Sara Pozzi, James Beene, Randy Vane, David Schultz 2010 University of Nebraska - Lincoln

Submillimeter-Resolution Radiography Of Shielded Structures With Laser-Accelerated Electron Beams, Viswanathan Ramanathan, Sudeep Banerjee, Nathan D. Powers, Nathaniel Cunningham, Nathan A. Chandler-Smith, Kun Zhao, Kevin Brown, Donald Umstadter, Shaun Clarke, Sara Pozzi, James Beene, Randy Vane, David Schultz

Donald Umstadter Publications

We investigate the use of energetic electron beams for high-resolution radiography of flaws embedded in thick solid objects. A bright, monoenergetic electron beam (with energy >100 MeV) was generated by the process of laser-wakefield acceleration through the interaction of 50-TW, 30-fs laser pulses with a supersonic helium jet. The high energy, low divergence, and small source size of these beams make them ideal for high-resolution radiographic studies of cracks or voids embedded in dense materials that are placed at a large distance from the source. We report radiographic imaging of steel with submillimeter resolution.


Movements Of Satellite-Monitored Humpback Whales From New Caledonia, Claire Garrigue, Alexandre N. Zerbini, Ygor Geyer, Mads-Peter Heide-Jørgensen, Wakao Hanaoka, Phil Clapham 2010 Ope´ration Ce´tace´s BP 12827 98802 Noume´a, New Caledonia

Movements Of Satellite-Monitored Humpback Whales From New Caledonia, Claire Garrigue, Alexandre N. Zerbini, Ygor Geyer, Mads-Peter Heide-Jørgensen, Wakao Hanaoka, Phil Clapham

Publications, Agencies and Staff of the U.S. Department of Commerce

Knowledge of the local and migratory movements of humpback whales (Megaptera novaeangliae) from New Caledonia is very limited. To investigate this topic, we attached satellite-monitored tags to 12 whales off southern New Caledonia. Tag longevity ranged from 1 to 52 days (X = 22.5 days). Tagged whales generally moved to the south or southeast, with several spending time in a previously unknown seamount habitat named Antigonia before resuming movement, generally toward Norfolk Island or New Zealand. However, 1 female with a calf traveled the entire length of the western coast of New Caledonia (~450 km) and then west in the ...


Seasonal Home Ranges And Fidelity To Breeding Sites Among Ringed Seals, Brendan P. Kelly, Oriana H. Badajos, Mervi Kunnasranta, John R. Moran, Micaela Martinez-Bakker, Peter Boveng, Douglas Wartzok 2010 University of Alaska Southeast

Seasonal Home Ranges And Fidelity To Breeding Sites Among Ringed Seals, Brendan P. Kelly, Oriana H. Badajos, Mervi Kunnasranta, John R. Moran, Micaela Martinez-Bakker, Peter Boveng, Douglas Wartzok

Publications, Agencies and Staff of the U.S. Department of Commerce

Population structure and patterns of habitat use among ringed seals (Phoca hispida) are poorly known, in part because seasonal movements have not been adequately documented. We monitored the movements of 98 ringed seals in the Beaufort and Chukchi seas between 1990 and 2006 using three forms of telemetry. In the winter—spring period (when the seals were occupying shorefast ice), we used radio and ultra-sonic tags to track movements above and below the ice, respectively. We used satellite-linked transmitters in summer and fall (when the seals ranged away from their winter sites) to track at-sea movements. In the shorefast ice ...


Distance Software: Design And Analysis Of Distance Sampling Surveys For Estimating Population Size, Len Thomas, Stephen T. Buckland, Eric A. Rexstad, Jeff L. Laake, Samantha Strindberg, Sharon L. Hedley, Jon R.B. Bishop, Tiago A. Marques, Kenneth P. Burnham 2010 Research Unit for Wildlife Population Assessment, Centre for Research into Ecological and Environmental Modelling, University of St. Andrews, St. Andrews KY16 9LZ, UK

Distance Software: Design And Analysis Of Distance Sampling Surveys For Estimating Population Size, Len Thomas, Stephen T. Buckland, Eric A. Rexstad, Jeff L. Laake, Samantha Strindberg, Sharon L. Hedley, Jon R.B. Bishop, Tiago A. Marques, Kenneth P. Burnham

Publications, Agencies and Staff of the U.S. Department of Commerce

1. Distance sampling is a widely used technique for estimating the size or density of biological populations. Many distance sampling designs and most analyses use the software Distance.

2. We briefly review distance sampling and its assumptions, outline the history, structure and capabilities of Distance, and provide hints on its use.

3. Good survey design is a crucial prerequisite for obtaining reliable results. Distance has a survey design engine, with a built-in geographic information system, that allows properties of different proposed designs to be examined via simulation, and survey plans to be generated.

4. A first step in analysis of ...


An Overview Of The Spread, Distribution, And Ecological Impacts Of The Quagga Mussel, Dreissena Rostriformis Bugensis, With Possible Implications To The Colorado River System, Thomas F. Nalepa 2010 NOAA

An Overview Of The Spread, Distribution, And Ecological Impacts Of The Quagga Mussel, Dreissena Rostriformis Bugensis, With Possible Implications To The Colorado River System, Thomas F. Nalepa

Publications, Agencies and Staff of the U.S. Department of Commerce

The quagga mussel (Dreissena rostriformis bugensis) was first found in the Great Lakes in 1989 and has since spread to all five lakes. Although its spread through the system was slower than that of the zebra mussel (Dreissena polymorpha), once established, it replaced zebra mussels in nearshore regions and is colonizing deep regions where zebra mussels were never found. Outside the Great Lakes Basin, quagga mussels do not appear to be increasing to any extent in the Ohio and Mississippi Rivers, even after being present in these rivers for over a decade. In contrast, numbers in the Colorado River system ...


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