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2015

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Full-Text Articles in Physical Sciences and Mathematics

Neurobehavioral And Gene Expression Effects Of Early Embryonic Methylmercury Exposure In Yellow Perch (Perca Flavescens) And Zebrafish (Danio Rerio) Larvae, Francisco Xavier Mora Zamorano Aug 2015

Neurobehavioral And Gene Expression Effects Of Early Embryonic Methylmercury Exposure In Yellow Perch (Perca Flavescens) And Zebrafish (Danio Rerio) Larvae, Francisco Xavier Mora Zamorano

Theses and Dissertations

Methylmercury (MeHg) is a pervasive and persistent neurotoxic environmental pollutant known to affect the behavior of fish, birds and mammals. The present study addresses the neurobehavioral and gene expression effects of MeHg in yellow perch (Perca flavescens) and zebrafish (Danio rerio) embryos. The rationale for this study originated from an interest to understand the behavioral and molecular phenotypes of environmental MeHg exposure in the yellow perch, an ecologically and economically relevant species of the North American Great Lakes region. Both MeHg and the yellow perch coexist in a common ecosystem: the North American Great Lakes. However, the effects of this …


Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her Aug 2015

Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs Stakeholder Needs Assessment for Broadening Participation in the Geoscience Workforce. Executive summary. The full meeting report is available at http://scholarworks.wmich.edu/geology_reports/1/


Climate Change Resilience And Socioeconomic Impacts Of Mpas And Mpa Networks In The Caribbean - Case Study: Evaluation Of The Effectiveness Of The Management Of Mpas And Coastal Zones In The Dominican Republic, Andrea Isabella Vogel Aug 2015

Climate Change Resilience And Socioeconomic Impacts Of Mpas And Mpa Networks In The Caribbean - Case Study: Evaluation Of The Effectiveness Of The Management Of Mpas And Coastal Zones In The Dominican Republic, Andrea Isabella Vogel

HCNSO Student Capstones

Many Caribbean nations have established MPAs to preserve marine biodiversity and maintain their economically important marine resources. In some Caribbean nations, in particular the Dominican Republic, most MPAs have failed in these respects and have remained “paper parks” due to being modeled along traditional conservation lines without careful consideration of socioeconomic factors, good management practices or increasingly important climate change factors. Successful Caribbean MPAs and MPA networks effectively function as refuges, attractions, sources of socioeconomic development and ecosystem-based climate change resilience mechanisms. The latter is of utmost importance to Small Island Developing States (SIDS) and other larger island developing states …


Dynamics Of Anisotropic Gold Nanopartilces In Synthetic And Biopolymer Solutions, Sharmine Alam Aug 2015

Dynamics Of Anisotropic Gold Nanopartilces In Synthetic And Biopolymer Solutions, Sharmine Alam

Wayne State University Dissertations

Soft matter is a subfield of condensed matter physics including systems such as polymers, colloids, amphiphiles and liquid crystals. Understanding their interaction and dynamics is essential for many interdisciplinary fields of study as well as important for technological advancements. We used gold nanorods (AuNRs) to investigate the length-scale dependent dynamics in semidilute polymer solutions, their conjugation and interaction with a protein bovine serum albumin (BSA), and the effect of shape anisotropy on the dynamics within a crowded solution of spheres. Multiphoton fluctuation correlation spectroscopy (MP-FCS) technique was used to investigate the translation and rotational diffusion of AuNRs. For polymer solutions, …


Probing The Past 30-Year Phenology Trend Of Us Deciduous Forests, X. Yue, N. Unger, Xiaoyang Zhang, C.S. Vogel Aug 2015

Probing The Past 30-Year Phenology Trend Of Us Deciduous Forests, X. Yue, N. Unger, Xiaoyang Zhang, C.S. Vogel

GSCE Faculty Publications

Phenology is experiencing dramatic changes over deciduous forests in the USA. Estimates of trends in phenology on the continental scale are uncertain, however, with studies failing to agree on both the magnitude and spatial distribution of trends in spring and autumn. This is due to the sparsity of in situ records, uncertainties associated with remote sensing data, and the regional focus of many studies. It has been suggested that reported trends are a result of recent temperature changes, though multiple processes are thought to be involved and the nature of the temperature forcing remains unknown. To date, no study has …


The Application And Analysis Of Midas/Gts In Landslide Control, Xiang Tao Aug 2015

The Application And Analysis Of Midas/Gts In Landslide Control, Xiang Tao

Innovative Research Publications IRP India

With the help of Midas/GTS software, we researched the landslide in mountain roads via analysis the force under its deadweight, understood the changes of the stress and strain and displacement of the slope, and analysis its force again that after joint the double-row anti-slide piles to the unstable area, until the slope reach a steady state at last, so as to attain the effect that prevent landslide disaster and deal with landslide event timely.


Environmental Forcing Does Not Induce Diel Or Synoptic Variation In The Carbon Isotope Content Of Forest Soil Respiration, Steven J. Hall, D. R. Bowling, J. E. Egan Aug 2015

Environmental Forcing Does Not Induce Diel Or Synoptic Variation In The Carbon Isotope Content Of Forest Soil Respiration, Steven J. Hall, D. R. Bowling, J. E. Egan

Steven J. Hall

Recent studies have examined temporal fluctuations in the amount and carbon isotope content (δ13C) of CO2 produced by the respiration of roots and soil organisms. These changes have been correlated with diel cycles of environmental forcing (e.g., sunlight and soil temperature) and with synoptic-scale atmospheric motion (e.g., rain events and pressure-induced ventilation). We used an extensive suite of measurements to examine soil respiration over 2 months in a subalpine forest in Colorado, USA (the Niwot Ridge AmeriFlux forest). Observations included automated measurements of CO2 and δ13C of CO2 in the soil efflux, the soil gas profile, and forest air. There …


Improved Detection By Ensemble-Decision Aliquot Ranking Of Circulating Tumor Cells With Low Numbers Of A Targeted Surface Antigen, Eleanor S. Johnson, Robbyn K. Anand, Daniel T. Chiu Aug 2015

Improved Detection By Ensemble-Decision Aliquot Ranking Of Circulating Tumor Cells With Low Numbers Of A Targeted Surface Antigen, Eleanor S. Johnson, Robbyn K. Anand, Daniel T. Chiu

Robbyn Anand

Circulating tumor cells (CTCs) are shed from a solid tumor into the bloodstream and can seed new metastases. CTCs hold promise for cancer diagnosis and prognosis and to increase our understanding of the metastatic process. However, their low numbers in blood and varied phenotypic characteristics make their detection and isolation difficult. One source of heterogeneity among CTCs is molecular: When they leave the primary tumor, these cells must undergo a molecular transition, which increases their mobility and chance of survival in the blood. During this molecular transition, the cells lose some of their epithelial character, which is manifested by the …


Invariance Explains Multiplicative And Exponential Skedactic Functions, Vladik Kreinovich, Olga Kosheleva, Hung T. Nguyen, Songsak Sriboonchitta Aug 2015

Invariance Explains Multiplicative And Exponential Skedactic Functions, Vladik Kreinovich, Olga Kosheleva, Hung T. Nguyen, Songsak Sriboonchitta

Departmental Technical Reports (CS)

In many situation, we have an (approximately) linear dependence between several quantities y = f(x1, ..., xn). The variance v of the corresponding approximation error often depends on the values of the quantities x1, ..., xn: v = v(x1, ..., xn); the function describing this dependence is known as the skedactic function. Empirically, two classes of skedactic functions are most successful: multiplicative functions v = c * |x1|γ1 * ... * |xn|γn and exponential functions v = exp(α + …


A Method For Measuring The Néel Relaxation Time In A Frozen Ferrofluid, Ronald J. Tackett, Jagdish Thakur, Nathaniel Mosher, Emily Perkins-Harbin, Ronald E. Kumon, Lihua Wang, Corneliu Rablau, Prem P. Vaishnava Aug 2015

A Method For Measuring The Néel Relaxation Time In A Frozen Ferrofluid, Ronald J. Tackett, Jagdish Thakur, Nathaniel Mosher, Emily Perkins-Harbin, Ronald E. Kumon, Lihua Wang, Corneliu Rablau, Prem P. Vaishnava

Physics Publications

We report a novel method of determining the average Néel relaxation time and its temperature dependence by calculating derivatives of the measured time dependence of temperature for a frozen ferrofluid exposed to an alternating magnetic field. The ferrofluid, composed of dextran-coated Fe3O4 nanoparticles (diameter 13.7 nm ± 4.7 nm), was synthesized via wet chemical precipitation and characterized by x-ray diffraction and transmission electron microscopy. An alternating magnetic field of constant amplitude (H0=20H0=20 kA/m) driven at frequencies of 171 kHz, 232 kHz, and 343 kHz was used to determine the temperature dependent magnetic energy absorption rate in the temperature range from …


The Sluggs Survey: Combining Stellar And Globular Cluster Metallicities In The Outer Regions Of Early-Type Galaxies, Nicola Pastorello, Duncan Forbes, Christopher Usher, Jean Brodie, Aaron Romanowsky, Jay Strader, Lee Spitler, Adebusola Alabi, Caroline Foster, Zachary Jennings, Sreeja Kartha, Vincenzo Pota Aug 2015

The Sluggs Survey: Combining Stellar And Globular Cluster Metallicities In The Outer Regions Of Early-Type Galaxies, Nicola Pastorello, Duncan Forbes, Christopher Usher, Jean Brodie, Aaron Romanowsky, Jay Strader, Lee Spitler, Adebusola Alabi, Caroline Foster, Zachary Jennings, Sreeja Kartha, Vincenzo Pota

Faculty Publications

The outer halo regions of early-type galaxies carry key information about their past accretion history. However, spectroscopically probing the stellar component at such galactocentric radii is still challenging. Using the DEep Imaging Multi-Object Spectrograph on the Keck, we have been able to measure the metallicities of the stellar and globular cluster components in 12 early-type galaxies out to more than 10Re. We find similar metallicity gradients for the metal-poor and metal-rich globular cluster subpopulations, suggesting a common formation process for the two subpopulations. This is in conflict with most current theoretical predictions, where the metal-poor globular clusters are thought to …


Factors Affecting Terrigenous Sedimentation In Coastal Bays With Coral Reefs: Implications For Monitoring The Effectiveness Of Watershed Restoration, Whitney Sears Aug 2015

Factors Affecting Terrigenous Sedimentation In Coastal Bays With Coral Reefs: Implications For Monitoring The Effectiveness Of Watershed Restoration, Whitney Sears

Theses

In the Caribbean, sedimentation has been identified as a serious threat to coral reef communities. Although land-based sediment delivery to coastal waters harboring coral reefs occurs under natural conditions, human activities in the watersheds above reefs increases the erosion and delivery of terrigenous sediment to the reefs. Delivery of terrigenous sediment into marine areas below developed watersheds affects sedimentation rates, alters the composition and texture of sediments that are suspended in the water column, and/or sediments that are deposited on the sea floor and on corals.

St. John, U.S. Virgin Islands is an ideal location to study the effects of …


Synthesis And Flammability Testing Of Epoxy Functionalized Phosphorous-Based Flame Retardants, Vladimir Benin, Xuemei Cui, Alexander Morgan, Karl Seiwert Aug 2015

Synthesis And Flammability Testing Of Epoxy Functionalized Phosphorous-Based Flame Retardants, Vladimir Benin, Xuemei Cui, Alexander Morgan, Karl Seiwert

Chemistry Faculty Publications

Several potential new phosphorus-containing flame retardant molecules were evaluated for heat release reduction potential by incorporation of the molecules into a polyurethane, generated from methylene diphenyl diisocyanate and 1,3-propane diol. The heat release reduction potential of these substances was evaluated using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods to qualitatively evaluate their potential reactivity into the polyurethane prior to heat release testing. The functionality of the flame retardants was epoxide based that would potentially react with the diol during polyurethane synthesis. Flammability testing …


Compton Scattering From The Deuteron Below Pion-Production Threshold, L. S. Myers, J. R. M. Annand, J. Brudvik, G. Feldman, K. G. Fissum, H. W. Grießhammer, K. Hansen, S. S. Henshaw, L. Isaksson, R. Jebali, Michael A. Kovash, M. Lundin, D. G. Middleton, A. M. Nathan, B. Schröder, S. C. Stave Aug 2015

Compton Scattering From The Deuteron Below Pion-Production Threshold, L. S. Myers, J. R. M. Annand, J. Brudvik, G. Feldman, K. G. Fissum, H. W. Grießhammer, K. Hansen, S. S. Henshaw, L. Isaksson, R. Jebali, Michael A. Kovash, M. Lundin, D. G. Middleton, A. M. Nathan, B. Schröder, S. C. Stave

Physics and Astronomy Faculty Publications

Differential cross sections for elastic scattering of photons from the deuteron have recently been measured at the Tagged-Photon Facility at theMAX IV Laboratory in Lund, Sweden. These first new measurements in more than a decade further constrain the isoscalar electromagnetic polarizabilities of the nucleon and provide the first-ever results above 100 MeV, where the sensitivity to the polarizabilities is increased. We add 23 points between 70 and 112 MeV, at angles 60, 120, and 150. Analysis of these data using a chiral effective field theory indicates that the cross sections are both self-consistent and …


Charm And Strange Quark Masses And FDS From Overlap Fermions, Yi-Bo Yang, Ying Chen, Andrei Alexandru, Shao-Jing Dong, Terrence Draper, Ming Gong, Frank X. Lee, Anyi Li, Keh-Fei Liu, Zhaofeng Liu, Michael Lujan Aug 2015

Charm And Strange Quark Masses And FDS From Overlap Fermions, Yi-Bo Yang, Ying Chen, Andrei Alexandru, Shao-Jing Dong, Terrence Draper, Ming Gong, Frank X. Lee, Anyi Li, Keh-Fei Liu, Zhaofeng Liu, Michael Lujan

Physics and Astronomy Faculty Publications

We use overlap fermions as valence quarks to calculate meson masses in a wide quark mass range on the 2 + 1-flavor domain-wall fermion gauge configurations generated by the RBC and UKQCD Collaborations. . . .

For the remainder of the abstract, please download this article or visit https://doi.org/10.1103/PhysRevD.92.034517


Infographics And Mathematics: A Mechanism For Effective Learning In The Classroom, Ivan Sudakov, Thomas Bellsky, Svetlana Usenyuk, Victoria V. Polyakova Aug 2015

Infographics And Mathematics: A Mechanism For Effective Learning In The Classroom, Ivan Sudakov, Thomas Bellsky, Svetlana Usenyuk, Victoria V. Polyakova

Physics Faculty Publications

This work discusses the creation and use of infographies in an undergraduate mathematics course. Infographies are a visualization of information combining data, formulas, and images. This article discusses how to form an infographic and uses infographics on topics within mathematics and climate as examples. It concludes with survey data from undergraduate students on both the general use of infographics and on the specific infographics designed by the authors.


Sexual Networks And Hiv Risk Among Black Men Who Have Sex With Men In 6 U.S. Cities, Hong-Van Tieu, Ting-Yuan Liu, Sophia Hussen, Matthew Connor, Lei Wang, Gregory Phillips Ii, + 11 More Aug 2015

Sexual Networks And Hiv Risk Among Black Men Who Have Sex With Men In 6 U.S. Cities, Hong-Van Tieu, Ting-Yuan Liu, Sophia Hussen, Matthew Connor, Lei Wang, Gregory Phillips Ii, + 11 More

Epidemiology Faculty Publications

Background

Sexual networks may place U.S. Black men who have sex with men (MSM) at increased HIV risk.

Methods

Self-reported egocentric sexual network data from the prior six months were collected from 1,349 community-recruited Black MSM in HPTN 061, a multi-component HIV prevention intervention feasibility study. Sexual network composition, size, and density (extent to which members are having sex with one another) were compared by self-reported HIV serostatus and age of the men. GEE models assessed network and other factors associated with having a Black sex partner, having a partner with at least two age category difference (age difference between …


Insights Into Planetesimal Evolution: Petrological Investigations Of Regolithic Howardites And Carbonaceous Chondrite Impact Melts, Nicole Gabriel Lunning Aug 2015

Insights Into Planetesimal Evolution: Petrological Investigations Of Regolithic Howardites And Carbonaceous Chondrite Impact Melts, Nicole Gabriel Lunning

Doctoral Dissertations

Asteroidal meteorites are the only available geologic samples from the early part of our solar system’s history. These meteorites contain evidence regarding how the earliest protoplanetary bodies formed and evolved. I use petrological and geochemical techniques to investigate the evolution of these early planetesimals, focusing on two meteorite types: Howardites, which are brecciated samples of a differentiated parent body (thought to be the asteroid 4 Vesta), and CV chondrites, which are primitive chondrites that have not undergone differentiation on their parent body.

Quantitative petrological analysis and characterization of paired regolithic (solar wind-rich) howardites indicate that this large sample of the …


Increasing The Sensitivity Of The Michelson Interferometer Through Multiple Reflection, Woonghee Youn Aug 2015

Increasing The Sensitivity Of The Michelson Interferometer Through Multiple Reflection, Woonghee Youn

Graduate Theses - Physics and Optical Engineering

Michelson interferometry has been one of the most famous and popular optical interference system for analyzing optical components and measuring optical metrology properties. Typical Michelson interferometer can measure object displacement with wavefront shapes to one half of the laser wavelength. As testing components and devices size reduce to micro and nano dimension, Michelson interferometer sensitivity is not suitable. The purpose of this study is to design and develop the Michelson interferometer using the concept of multiple reflections. This thesis proposes a new and novel design for a multiple reflection interferometer, where the number of reflections does not affect the quality …


Geo-Needs: Stakeholder Needs Assessment For Broadening Participation In The Geoscience Workforce, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her Aug 2015

Geo-Needs: Stakeholder Needs Assessment For Broadening Participation In The Geoscience Workforce, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs focus group meetings report from the August 5-7 and 9-11, 2015 conference at the Nothern Illinois University Conference Center in Naperville, Illinois.

Despite a significant investment of resources, underrepresented minorities constitute ~8% of the geoscience-related workforce, making the geosciences one of the least diverse of all science, technology, engineering, and math (STEM) disciplines. While this pattern of underrepresentation has been attributed to numerous factors, the Geo-Needs project is focused on lack of access to undergraduate courses and programs of study at two-year technical and community colleges (2YCs) and minority-serving institutions (MSIs). Based on our analysis, only about 2.5% of …


The Edge Group Coloring Problem With Applications To Multicast Switching, Jonathan Turner Aug 2015

The Edge Group Coloring Problem With Applications To Multicast Switching, Jonathan Turner

All Computer Science and Engineering Research

This paper introduces a natural generalization of the classical edge coloring problem in graphs that provides a useful abstraction for two well-known problems in multicast switching. We show that the problem is NP-hard and evaluate the performance of several approximation algorithms, both analytically and experimentally. We find that for random χ-colorable graphs, the number of colors used by the best algorithms falls within a small constant factor of χ, where the constant factor is mainly a function of the ratio of the number of outputs to inputs. When this ratio is less than 10, the best algorithms produces solutions that …


Enantiospecific Stereospecific Strategy For The Total Synthesis Of Sarpagine And Macroline Related Oxindole Alkaloids: First Total Synthesis Of Affinisine Oxindole, Isoalstonisine, Alstofoline, Macrogentine, N(1)-Demethylalstonisine, Alstonoxine A And Second Generation Synthesis Of Alstonisine, German Oscar Fonseca Cabrera Aug 2015

Enantiospecific Stereospecific Strategy For The Total Synthesis Of Sarpagine And Macroline Related Oxindole Alkaloids: First Total Synthesis Of Affinisine Oxindole, Isoalstonisine, Alstofoline, Macrogentine, N(1)-Demethylalstonisine, Alstonoxine A And Second Generation Synthesis Of Alstonisine, German Oscar Fonseca Cabrera

Theses and Dissertations

The (7R)-sarpagine/macroline related oxindole alkaloids (-)-isoalstonisine (27) and (-)-macrogentine (31) together with the (7S)-sarpagine/macroline related oxindole alkaloids (-)-affinisine oxindole (24), (-)-alstonoxine A (19), (+)-alstonisine (8, second generation total synthesis), (+)-Na-demethylalstonisine (17) and (+)-alstofoline (18) were concisely synthesized during these studies.

These oxindole alkaloids were isolated from plants of the genus Alstonia which is characterized by the preponderance of sarpagine/macroline-type indole and oxindole alkaloids. Plants that belong to this genus are mainly distributed over tropical regions of Central America, Africa, and Asia where they are used locally in traditional medicine, for example, in the treatment of malaria and dysentery. The main …


Smooth Representation Of Functions On Non-Periodic Domains By Means Of The Fourier Continuation Method, Nicholas Rubel, David Bilyeu, Justin Koo Aug 2015

Smooth Representation Of Functions On Non-Periodic Domains By Means Of The Fourier Continuation Method, Nicholas Rubel, David Bilyeu, Justin Koo

STAR Program Research Presentations

This report examines a new methodology in solving Partial Differential Equations (PDEs) numerically. The report also studies the accuracy of this new method as a PDE solver. This new Fourier Continuation (FC) method is one of a few that avoids the well-known Gibbs Phenomenon, which is the overestimation or underestimation of a function. These estimations are oscillations around a “jump” when a non-periodic function is expressed in terms of sines and cosines. Instead, the FC algorithm creates a smooth, periodic extension of a function over a general domain, as demonstrated by the many examples presented here. The FC algorithm was …


Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman Aug 2015

Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman

STAR Program Research Presentations

The primary purpose of this study is to better understand how climate affects river dynamics. It is also important to understand the relationship between glaciers and the transportation of sediments, as this allows us to study changes in transport through time. The studied sediments were gathered from outcrops located in Fresno Ca, off of Friant road. The origin of these sediments are the Sierra Nevada Mountains. Mesozoic metasedimentary and metavolcanic sediments are derived from the foothills, while the granitic sediments are derived from higher up in the mountains. The sediments are characterized by both their degree of rounding, and their …


Using Bromide Tracer To Measure Uranium Diffusivity In Ground Water Sediments, Francis Michael Tee, Morris E. Jones, Megan K. Dustin, Sharon Bone, John Bargar Aug 2015

Using Bromide Tracer To Measure Uranium Diffusivity In Ground Water Sediments, Francis Michael Tee, Morris E. Jones, Megan K. Dustin, Sharon Bone, John Bargar

STAR Program Research Presentations

More than 129 million liters of groundwater are contaminated with uranium at Old Rifle, Colorado – a former uranium-processing site that operated until 1958. The original Department of Energy (DOE) strategy for remediation, involving natural flushing of U from the groundwater through mixing with surface water, has not proven successful. Thin pockets of silt-, clay-, and organic-rich sediments referred to as naturally reduced zones (NRZs) act both as sinks and sources of U to the aquifer, contribute to plume persistence, and appear to be diffusion limited controlled.

To better understand how the NRZs are diffusion limited controlled, a bromide tracer …


Wet Chemical Synthesis And Characterization Of Nanomaterials For Solar Cell Applications, Krystle N. Sy, Ramprasad Gandhiraman, Jessica E. Koehne Aug 2015

Wet Chemical Synthesis And Characterization Of Nanomaterials For Solar Cell Applications, Krystle N. Sy, Ramprasad Gandhiraman, Jessica E. Koehne

STAR Program Research Presentations

During long term space missions, it is necessary to have a reliable source of energy. Solar cells are an easy and reliable way to convert energy from the sun to electrical energy. NASA has used solar cells manufactured on Earth as an energy source for many of its missions. In order to develop technologies that will enable high efficiency solar cells, we are synthesizing nanostructured materials. A range of nanostructured materials, such as titanium dioxide nanowires, nickel nanoparticles, copper nanoparticles, and silver nanoparticles/nanowires, are synthesized. In this work, we are reporting on the synthesis of these nanomaterials and the electron …


Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman Aug 2015

Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman

STAR Program Research Presentations

Tropical forest soils have an important role in global carbon (C) stocks. Small changes in the cycling of C could drastically affect atmospheric carbon dioxide (CO2) concentrations and active cycling of carbon in a forest community. Currently, little is understood of how tropical forest soils will respond to the increasing global temperatures. To examine the effects of warming/ drought on losses of older versus younger soil C pools, we implemented radiocarbon (14C) isotopic characterization of various soil plot samples and depths from the Luquillo Experimental Forest, Puerto Rico. 14C was measured using Accelerated Mass Spectrometry (AMS) from catalytically condensed carbon …


Resolving Emission Lines Of Sodiumlike Fe Xvi Using Ebit, Sandi Lavito Aug 2015

Resolving Emission Lines Of Sodiumlike Fe Xvi Using Ebit, Sandi Lavito

STAR Program Research Presentations

High resolution crystal spectrometers on sounding rockets and orbiting satellites, such as the Solar Maximum Mission, show strong X-ray emission from the n= 3 to 2 transitions in neon-like Fe XVII. Two of the strongest lines are the 3d to 2p resonance and inter combination lines at 15.01 Å (3C) and 15.26 Å (3D).

Intensity ratios of these solar lines range from ~ 1.6 to 2.8. The lower ratios are a result of a line from Na-like Fe XVI inner shell satellite line blending with the Fe XVII inter combination line, 3D. The wavelength of the Na-like line is not …


Temperature Distribution And Thermal Anomalies Along A Flowline Of The Greenland Ice Sheet, Joel A. Harrington, Neil F. Humphrey, Joel T. Harper Aug 2015

Temperature Distribution And Thermal Anomalies Along A Flowline Of The Greenland Ice Sheet, Joel A. Harrington, Neil F. Humphrey, Joel T. Harper

Geosciences Faculty Publications

Englacial and basal temperature data for the Greenland ice sheet (GrIS) are sparse and mostly limited to deep interior sites and ice streams, providing an incomplete representation of the thermal state of ice within the ablation zone. Here we present 11 temperature profiles at five sites along a 34km east-west transect of West Greenland. These profiles depict ice temperatures along a flowline and local temperature variations between closely spaced boreholes. A temperate basal layer is present in all profiles, increasing in thickness in the flow direction, where it expands from about 3% of ice height furthest inland to 100% at …


Heun Polynomials In The Construction Of Vector Valued Slepian Functions On A Spherical Cap, Thomas Anthony Ventimiglia Aug 2015

Heun Polynomials In The Construction Of Vector Valued Slepian Functions On A Spherical Cap, Thomas Anthony Ventimiglia

Theses and Dissertations

I summarize the existing work on the problem of finding vector valued Slepian functions on the unit sphere: separable vector fields whose energy is concentrated within a compact region; in this case, a spherical cap. The radial and tangential components are independent for an appropriate choice of basis, and for each component the problem is recast as that of finding real eigenfunctions of an integral operator. There exist Sturm-Liouville differential operators that commute with these integral operators and hence share their eigenfunctions. Therefore, the radial and tangential eigenfunctions are solutions to second order linear ODEs. After introducing the Heun differential …