Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2013

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 11161 - 11190 of 11462

Full-Text Articles in Physical Sciences and Mathematics

Sea Level Rise And Flooding Risk In Virginia, Larry P. Atkinson, Tal Ezer, Elizabeth Smith Jan 2013

Sea Level Rise And Flooding Risk In Virginia, Larry P. Atkinson, Tal Ezer, Elizabeth Smith

CCPO Publications

Consistent rises in sea level have occurred throughout the world for thousands of years. Flooding, storm surges, and other consequences of the rise in sea level have had widespread effects on coastal communities across the globe. Nowhere is this more apparent than the Norfolk/Virginia Beach region along the U.S. Atlantic coastline, where the sea level is rising more rapidly than the global average. This article discusses the causes of and the differences between the rise in sea levels globally and the rise of the sea level in the mid-­Atlantic region of the United States. The article also emphasizes the problems …

Go to article

Gis Data: City Of Poquoson, Virgina Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Carl Hershner, David Stanhope, David Weiss, Julie Bradshaw, Christine Tombleson Jan 2013

Gis Data: City Of Poquoson, Virgina Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Carl Hershner, David Stanhope, David Weiss, Julie Bradshaw, Christine Tombleson

Data

The Shoreline Management Model is a GIS spatial model that determines appropriate shoreline best management practices using available spatial data and decision tree logic. Available shoreline conditions used in the model include the presence or absence of tidal marshes, beaches, and forested riparian buffers, bank vegetation cover, bank height, wave exposure (fetch), nearshore water depth, and proximity of coastal development to the shoreline. The model output for shoreline best management practices is displayed in the locality Comprehensive Map Viewer. One GIS shapefile is developed that describes two arcs or lines representing practices in the upland area and practices at the …

Go to article

Human Factors And Cultural Influences In Implementing Agile Philosophy And Agility In Global Software Development, Anuradha Sutharshan Jan 2013

Human Factors And Cultural Influences In Implementing Agile Philosophy And Agility In Global Software Development, Anuradha Sutharshan

Theses: Doctorates and Masters

As software becomes increasingly important to all aspects of industry, developers should be encouraged to adopt best practice and hence improve the quality of the processes used, and achieve targets relating to time, budget and quality. In the software industry, several software methodologies have been used to address software development problems; however some of these processes may be too bureaucratic. The Agile Alliance formed in 2001, sought to address this problem; accordingly, they developed a manifesto and twelve principles, to which all agile software methods adhere. The purpose of the manifesto and its principles is to uncover better ways of …

Go to article

The Relationship Between The Meaning Of Water And Sense Of Place : A Grounded Theory Study From Northern Thailand, Katesuda Sitthisuntikul Jan 2013

The Relationship Between The Meaning Of Water And Sense Of Place : A Grounded Theory Study From Northern Thailand, Katesuda Sitthisuntikul

Theses: Doctorates and Masters

The literature suggests that a subtle relationship exists for communities between the meaning of water and sense of place, making fertile ground for systematic investigation. The relationship has obvious importance in today’s world, where people’s reliance on water, and the need for reliable supplies, form part of a common discourse in natural resource management. Yet, there has been much less discussion of what water means to people, how it connects with peoples’ sense of place, and what that might mean for the way people interact with their surroundings. The methodology of constructivist grounded theory was therefore appropriate to investigate this …

Go to article

Resilience In Quaking Aspen: Recent Advances And Future Needs, Paul C. Rogers, C. Eisenberg, S. Clair Jan 2013

Resilience In Quaking Aspen: Recent Advances And Future Needs, Paul C. Rogers, C. Eisenberg, S. Clair

Wildland Resources Faculty Publications

Quaking Aspen (Populus tremuloides) sustainability is a topic of intense interest in forest ecology. Reports range from declines to persisting or increasing coverage in some areas. Moreover, there is little agreement on ultimate factors driving changes. Low aspen recruitment has been attributed to climate patterns, past management, herbivore increases, competitive interactions with conifers, predator and beaver extirpation, and livestock grazing. Several of these potential causes result from direct or indirect actions of human agency. On June 27–28, 2012 a group of leading aspen ecologists from diverse backgrounds convened at the High Lonesome Ranch in western Colorado to address the state …

Go to article

Turbulent Collision-Coalescence In Maritime Shallow Convection, A. A. Wyszogrodzki, W.W. Grabowski, L. P. Wang, Orlando Ayala Jan 2013

Turbulent Collision-Coalescence In Maritime Shallow Convection, A. A. Wyszogrodzki, W.W. Grabowski, L. P. Wang, Orlando Ayala

Engineering Technology Faculty Publications

This paper discusses cloud simulations aiming at quantitative assessment of the effects of cloud turbulence on rain development in shallow ice-free convective clouds. Cloud fields from large-eddy simulations (LES) applying bin microphysics with the collection kernel enhanced by cloud turbulence are compared to those with the standard gravitational collection kernel. Simulations for a range of cloud condensation nuclei (CCN) concentrations are contrasted. Details on how the parameterized turbulent collection kernel is used in LES simulations are presented. Because of the disparity in spatial scales between the bottom-up numerical studies guiding the turbulent kernel development and the top-down LES simulations of …

Go to article

Three-Dimensional Hydrostratigraphy Of The Firth, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping In The Eastern Nebraska Water Resources Assessment (Enwra), Jesse T. Korus, R. Matthew Joeckel, Dana Divine Jan 2013

Three-Dimensional Hydrostratigraphy Of The Firth, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping In The Eastern Nebraska Water Resources Assessment (Enwra), Jesse T. Korus, R. Matthew Joeckel, Dana Divine

Conservation and Survey Division

No abstract provided.

Go to article

Three-Dimensional Hydrostratigrapy Of The Swedeburg, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping For The Eastern Nebraska Water Resources Assessment (Enwra), Dana Divine, Jesse T. Korus Jan 2013

Three-Dimensional Hydrostratigrapy Of The Swedeburg, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping For The Eastern Nebraska Water Resources Assessment (Enwra), Dana Divine, Jesse T. Korus

Conservation and Survey Division

No abstract provided.

Go to article

Nebraska Statewide Groundwater-Level Monitoring Report 2013, A. R. Young, M. E. Burbach, L. M. Howard Jan 2013

Nebraska Statewide Groundwater-Level Monitoring Report 2013, A. R. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division

No abstract provided.

Go to article

Saturated Thickness Of The Unconfined Portions Of The High Plains Aquifer, Conservation And Survey Division Jan 2013

Saturated Thickness Of The Unconfined Portions Of The High Plains Aquifer, Conservation And Survey Division

Conservation and Survey Division

No abstract provided.

Go to article

Groundwater-Level Changes In Nebraska - Spring 2012 To Spring 2013, A. Young, M. E. Burbach, L. M. Howard Jan 2013

Groundwater-Level Changes In Nebraska - Spring 2012 To Spring 2013, A. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division

No abstract provided.

Go to article

Excited State Calculations In Solids By Auxiliary-Field Quantum Monte Carlo, Fengjie Ma, Shiwei Zhang, Henry Krakauer Jan 2013

Excited State Calculations In Solids By Auxiliary-Field Quantum Monte Carlo, Fengjie Ma, Shiwei Zhang, Henry Krakauer

Arts & Sciences Articles

We present an approach for ab initio many-body calculations of excited states in solids. Using auxiliary-field quantum Monte Carlo, we introduce an orthogonalization constraint with virtual orbitals to prevent collapse of the stochastic Slater determinants in the imaginary-time propagation. Trial wave functions from density-functional calculations are used for the constraints. Detailed band structures can be calculated. Results for standard semiconductors are in good agreement with experiments; comparisons are also made with GW calculations and the connections and differences are discussed. For the challenging ZnO wurtzite structure, we obtain a fundamental band gap of 3.26(16) eV, consistent with experiments.

Go to article

Analysis Of Spark Versus Non-Spark Mediated Sr Calcium Leak Using A Langevin Description Of Stochastic Calcium Release, Xiao Wang, Seth H. Weinberg, Gregory D. Smith, Yan Hao, Eric A. Sobie Jan 2013

Analysis Of Spark Versus Non-Spark Mediated Sr Calcium Leak Using A Langevin Description Of Stochastic Calcium Release, Xiao Wang, Seth H. Weinberg, Gregory D. Smith, Yan Hao, Eric A. Sobie

Arts & Sciences Articles

No abstract provided.

Go to article

Mountain Goat Genetic Diversity And Population Connectivity In Washington And Southern British Columbia, Leslie C. (Leslie Claire) Parks Jan 2013

Mountain Goat Genetic Diversity And Population Connectivity In Washington And Southern British Columbia, Leslie C. (Leslie Claire) Parks

WWU Graduate School Collection

Anthropogenic alterations to natural landscapes and the associated habitat fragmentation, habitat degradation, and climatic shifts threaten biodiversity from the local to the global scale. These perturbations disrupt historical patterns of gene flow causing reduced population connectivity, loss of genetic diversity, and increased risk of extinction. A landscape that is permeable to animal movement counteracts local population fluctuations, increases genetic diversity, increases adaptive potential, and provides corridors for range shifts in response to climate change. Maintaining population connectivity is critical for the conservation of small populations isolated by fragmented landscapes. This strategy requires an accurate understanding of the landscape's effect on …

Go to article

Factors Affecting The Distribution And Abundance Of The Salish Sucker (Catostomus Sp.): An Endemic And Endangered Transboundary Fish Population, Nathaniel S. (Nathaniel Stuart) Lundgren Jan 2013

Factors Affecting The Distribution And Abundance Of The Salish Sucker (Catostomus Sp.): An Endemic And Endangered Transboundary Fish Population, Nathaniel S. (Nathaniel Stuart) Lundgren

WWU Graduate School Collection

The Salish sucker (Catostomus sp.) is a recently described endemic fish species with a patchy distribution and a narrow geographic range in western Washington and southwestern British Columbia. In this study I examined populations within the Nooksack River watershed, attempting to elucidate the environmental factors contributing to observed patterns of distribution and abundance. I hypothesized that hypoxic and hyperthermic conditions during the summer months would restrict Salish sucker distribution. I tested this hypothesis by measuring dissolved oxygen concentrations, temperature, and Salish sucker abundance and movement at eight sites in the Bertrand Creek and Fishtrap Creek sub-basins. The results of this …

Go to article

Synthesis Of Alignable Fluorophores For Use In Luminescent Solar Concentrators, Willie E. Benjamin Jan 2013

Synthesis Of Alignable Fluorophores For Use In Luminescent Solar Concentrators, Willie E. Benjamin

WWU Graduate School Collection

Luminescent Solar Concentrators (LSCs) collect and concentrate sunlight for use in solar power generation. First proposed over 30 years ago, LSCs are simple devices consisting of a planar waveguide coated or impregnated with a fluorophore. Sunlight absorbed by the fluorophore, reemitted into the waveguide, and concentrated at the edges of the collector. The most substantial problem with previous iterations of LSC technology is that they suffer from escape cone losses (photons lost through the top and bottom of the waveguide) that limited their size and efficiency. In this study, the reduction in escape cone losses was studied through alignment of …

Go to article

Characterization Of Coarse Sediment Transport On A Mixed Sand And Gravel Beach: Cherry Point Aquatic Reserve, Blaine, Washington, Meghan E. (Meghan Elizabeth) Weaver Jan 2013

Characterization Of Coarse Sediment Transport On A Mixed Sand And Gravel Beach: Cherry Point Aquatic Reserve, Blaine, Washington, Meghan E. (Meghan Elizabeth) Weaver

WWU Graduate School Collection

This study examines coarse-sediment transport behavior on a mixed sand and gravel (MSG) beach at Cherry Point Aquatic Reserve in Blaine, Washington. Radio Frequency Identifier (RFId) Passive Integrated Transponder (PIT) tags were used to trace large pebbles and cobbles (51 - 129 mm in diameter) between mid-January and early-March, 2012. Transport data were combined with wind, current and water level data recorded by nearby weather stations, as well as wave data collected by an offshore pressure sensor, into a comprehensive data set. Tide, wind and wave parameters were then input into XBeach, a relatively new nearshore numerical model [Roelvink et …

Go to article

Metamorphic Evolution Of The Northwest Chelan Block, North Cascades, Washington, Aaron A (Aaron Arthur) Fitts Jan 2013

Metamorphic Evolution Of The Northwest Chelan Block, North Cascades, Washington, Aaron A (Aaron Arthur) Fitts

WWU Graduate School Collection

The Cascades crystalline core (CC) is the fault bound southern extension of the Coast Plutonic Complex, a Cretaceous orogenic welt that forms the northernmost section of the North American Cordillera. Of primary interest in this study is the tectonic history of the Cascade River region in the northwest of CC. The Sibley Creek area of the Cascade River region is a zone of high-grade metamorphic rocks bound by Cretaceous plutons to the north, east, and west and the Tertiary Entiat fault to the south. Analysis of deformed and undeformed granitic plutons in the area could help constrain the absolute ages …

Go to article

Silk Fibroin-Based Conducting Polymer Composite Electrodes And Their Use As Electromechanical Actuators, Isabella S. Romero Jan 2013

Silk Fibroin-Based Conducting Polymer Composite Electrodes And Their Use As Electromechanical Actuators, Isabella S. Romero

WWU Graduate School Collection

In order to produce conductive, biocompatible and mechanically robust materials for use in bioelectrical applications, we have developed a new strategy to selectively incorporate poly(pyrrole) (Ppy) into constructs made from silk fibroin. Here, we demonstrate that covalent attachment of negatively charged, hydrophilic sulfonic acid groups to the silk protein can selectively promote pyrrole absorption and polymerization within the modified films to form a conductive, interpenetrating network of Ppy and silk that is incapable of delamination. To further increase the conductivity and long-term stability of the Ppy network, a variety of small molecule sulfonic acid dopants were utilized and the properties …

Go to article

Regional Risk Assessment Of The Puyallup River Watershed And The Evaluation Of Low Impact Development In Meeting Management Goals, Eleanor Hines Jan 2013

Regional Risk Assessment Of The Puyallup River Watershed And The Evaluation Of Low Impact Development In Meeting Management Goals, Eleanor Hines

WWU Graduate School Collection

The Relative Risk Model (RRM) is a tool used to calculate and assess the likelihood of effects to endpoints when multiple stressors occur in complex ecological systems. In this study a Bayesian network was used to calculate relative risk and uncertainty (BN-RRM) in the Puyallup River Watershed. First, I calculated the risk of prespawn mortality of coho salmon. Second, I evaluated the effect of low impact development (LID) as a means to reduce risk. Prespawner mortality in coho salmon within the Puyallup watershed was the endpoint selected for this study. A conceptual model showing causal pathways between stressors and endpoints …

Go to article

Diastereoselective Intramolecular Carbonyl Hydrosilation For Complex Polyketide Synthesis, Casey R. Medina Jan 2013

Diastereoselective Intramolecular Carbonyl Hydrosilation For Complex Polyketide Synthesis, Casey R. Medina

WWU Graduate School Collection

It has been found that β-hydroxyketone compounds can be reduced to the corresponding 1,3-diol through an intramolecular carbonyl hydrosilation. Furthermore, because this hydrosilation proceeds through a cyclic 6-membered ring transition state, this reduction can be performed diastereoselectively by placing a stereocenter on the 6-membered ring transition state. Prior to further investigations into this diastereoselective intramolecular carbonyl hydrosilation, a streamlined synthesis of β-hydroxyketone compounds has been developed. This new synthesis features an enone diboration/oxidation sequence found to be successful on a broad scope of enones in high yields. Further studies have shown that placing a stereocenter outside of the transition state …

Go to article

¹⁵N Heteronuclear Single Quantum Coherence Backbone Assignment Of Cyanomet Isoform Sperm Whale Myoglobin And Permutant, James M. (James Morgan) Hall Jan 2013

¹⁵N Heteronuclear Single Quantum Coherence Backbone Assignment Of Cyanomet Isoform Sperm Whale Myoglobin And Permutant, James M. (James Morgan) Hall

WWU Graduate School Collection

The relationship between backbone dynamics and stability in circularly permuted globins is not well understood. HGL16 is a circular permutant of sperm whale myoglobin (sw Mb) in which the amino and carboxyl termini have been linked by 16 amino acids, (GlyGlyGlySer)4. New termini have been generated between the G and H helices. This permutant was shown to be 5.2 kcal/mol less stable than the wild-type protein. Backbone dynamic studies of permuted globins via 15N Heteronuclear Single Quantum Coherence (NHSQC) nuclear magnetic resonance (NMR) experiments may help achieve a better understanding to the observed stability changes observed. The assignments of both …

Go to article

Structural And Functional Characterization Of Villin Domain 6 And Supervillin N-Terminal Fragments, Stanislav Fedetchkine Jan 2013

Structural And Functional Characterization Of Villin Domain 6 And Supervillin N-Terminal Fragments, Stanislav Fedetchkine

WWU Graduate School Collection

The protein villin is a member of the gelsolin superfamily, and regulates cytoskeleton formation in the brush border at the apical end of epithelial cells. The six villin domains (V1-V6) form which contain a Ca²+ -dependent actin-binding site associated with the V1-V3 fragment. The six villin domains are homologous to gelsolin and have ~50% sequence identity. In the absence of calcium, gelsolin adopts a compact, inactive conformation stabilized by a 12-residue C-terminal helix. This helix locks domains G2 and G6 as a "latch" in low calcium and releases at higher calcium levels. Tyrosine phosphorylation, phosphatidylinositol 4,5-bisphosphate (PIP2) and calcium concentration …

Go to article

Thermal And Hydrological Conditions Of The Goethe Rock Glacier, Central Sierra Nevada, California, Jezra Beaulieu Jan 2013

Thermal And Hydrological Conditions Of The Goethe Rock Glacier, Central Sierra Nevada, California, Jezra Beaulieu

WWU Graduate School Collection

The potential of rock glaciers in the Sierra Nevada to provide critical hydrological reservoirs and ecological habitats in a changing climate remains largely untested. In an effort to constrain the microclimatic contributions of buried ice, continuous temperatures were recorded in the near-surface debris of a variety of ice-cored and associated landforms in the Goethe cirque from August 2011 and July 2012 (Goethe rock glacier=GRG, valley-wall rock glaciers=VRG, Recess Peak debris=RPD, talus=TAL, ranging from most ice to least ice). In addition, continuous meteorological conditions on the rock glacier and stage of the main meltwater outwash stream were recorded to assess temporal …

Go to article

Development Of Surface-Enhanced Raman Based Sensors, Elizabeth C. (Elizabeth Cecilia) Wellner Jan 2013

Development Of Surface-Enhanced Raman Based Sensors, Elizabeth C. (Elizabeth Cecilia) Wellner

WWU Graduate School Collection

While the medical field incorporates various imaging methods for diagnosis and treatment, there is a need for continual development of real-time in vivo imaging techniques in this field. A surface-enhanced Raman scattering (SERS) based fiber optic sensor is reported. An optical fiber was coated in gold nanoparticles, capable of Raman scattering. SERS active molecules were adsorbed onto the gold nanoparticle film, and SERS spectra obtained. Using 4-mercaptopyridine as a SERS reporter molecule, the chemical environment surrounding the probe was determined by the analysis of the pH sensitive SERS spectra. The methods of preparation and characterization of the SERS-based fiber sensors …

Go to article

Structural And Functional Characterization Of A Permuted Hemoglobin, Michael P. (Michael Patrick) Murphy Jan 2013

Structural And Functional Characterization Of A Permuted Hemoglobin, Michael P. (Michael Patrick) Murphy

WWU Graduate School Collection

The tetrameric composition of human hemoglobin complicates protein engineering efforts that are required to improve its potential as an oxygen-carrying therapeutic. In our research to design a single-chain version of the hemoglobin molecule (scHb), we have co-expressed a circularly permuted human β-globin (cp-β) with human α-globin. At micromolar concentrations, the purified recombinant globins appear to associate to form an α-cpβ heterodimer in solution rather than the expected α2-cpβ2 heterotetramer. Compared to recombinant human hemoglobin, the α-cpβ heterodimer exhibits a stronger ligand binding affinity. Knowledge of the intermolecular interactions favoring formation of the α-cpβ heterodimer will be instrumental in understanding the …

Go to article

Globin Engineering Studies: Optimizing The Designs Of Circularly Permuted Myoglobin And Single-Chain Hemoglobin, Jamie M. (Jamie Marie) Apperson Jan 2013

Globin Engineering Studies: Optimizing The Designs Of Circularly Permuted Myoglobin And Single-Chain Hemoglobin, Jamie M. (Jamie Marie) Apperson

WWU Graduate School Collection

We are working to produce a stable and effective hemoglobin-based oxygen carrier (HBOC) for critical care. Mammalian myoglobins are good model systems for the protein engineering of human hemoglobin, and in the current work, our aim is to generate a circularly permuted myoglobin with increased thermodynamic stability compared to previous permuteins characterized by our lab. Our initial permuted myoglobin, HGL16, includes a 16-residue Gly-Ser linker (SGGG)4 between the A and H helices in sperm whale myoglobin (swMb). Although HGL16 was shown to fold and function like wild-type swMb, its stability was reduced significantly. In the current work, computational design of …

Go to article

Determining Garnet Crystallization Kinetics From Growth Zoning And Mn-Calibrated Sm-Nd Ages, Rose Bloom Jan 2013

Determining Garnet Crystallization Kinetics From Growth Zoning And Mn-Calibrated Sm-Nd Ages, Rose Bloom

WWU Graduate School Collection

By working under the assumption that garnet strongly fractionates Mn, the change in measured XMn from the core to rim of a garnet can be used to represent the progression of time since nucleation. Core, mantle, and rim zones from nine snowball garnets collected at the Pinney Hollow Formation, Townshend Dam, VT were analyzed using electron probe microanalysis (EPMA) as well as Sm/Nd isotopic methods. Two-point garnet-matrix Sm/Nd ages are complex, with some showing apparent reverse age zoning and unrealistically young ages. Therefore, some garnet ages were culled, including those with poor 147Sm/144Nd ratios (< 0.75), low Nd concentrations (> 0.2 ppm), and rim ages …

Go to article

Geomechanics And Elastic Anisotropy Of The Bakken Formation, Williston Basin, Mehdi Ostadhassan Jan 2013

Geomechanics And Elastic Anisotropy Of The Bakken Formation, Williston Basin, Mehdi Ostadhassan

Theses and Dissertations

Many of the earth’s rocks exhibit anisotropic characteristics. Anisotropy is particularly common in many sedimentary rocks, such as shales. Anisotropy is defined as the spatial alignment of mineral grains, layers, fractures and stresses which causes elastic wave velocity and other elastic properties to vary with direction. There are two types of anisotropy: intrinsic and stress-induced. Intrinsic anisotropy is caused by beddings, microstructures or aligned fractures formed during deposition. Stress-induced anisotropy is caused by strain associated with external stresses. Intrinsic anisotropy originates in the absence of external stresses, while stress-induced anisotropy results from tectonic and overburden stresses. The style of earth …

Go to article

Next-Peak: A Normal-Exponential Two-Peak Model For Peak-Calling In Chip-Seq Data, Nak-Kyeong Kim, Rasika V. Jayatillake, John L. Spouge Jan 2013

Next-Peak: A Normal-Exponential Two-Peak Model For Peak-Calling In Chip-Seq Data, Nak-Kyeong Kim, Rasika V. Jayatillake, John L. Spouge

Mathematics & Statistics Faculty Publications

Background: Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) can locate transcription factor binding sites on genomic scale. Although many models and programs are available to call peaks, none has dominated its competition in comparison studies.

Results: We propose a rigorous statistical model, the normal-exponential two-peak (NEXT-peak) model, which parallels the physical processes generating the empirical data, and which can naturally incorporate mappability information. The model therefore estimates total strength of binding (even if some binding locations do not map uniquely into a reference genome, effectively censoring them); it also assigns an error to an estimated binding location. The comparison study …

Go to article

First Prev Next Last