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2003

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Articles 1471 - 1500 of 2071

Full-Text Articles in Engineering

Microscale Electrospinning Of Polymer Nanofiber Interconnections, Royal Kessick, Gary C. Tepper Jan 2003

Microscale Electrospinning Of Polymer Nanofiber Interconnections, Royal Kessick, Gary C. Tepper

Chemical and Life Science Engineering Publications

Polymer fiber interconnects were produced between microscale features on a substrate using only electrostatic forces. Electric-field-driven directed growth of nanoscale carboxymethylcellulose fibers was achieved between microscale droplets of a concentrated polymer solution. The fibers were studied using atomic force and scanning electron microscopy and were observed to emerge from the tip of conical protrusions formed at the surface of the droplets. The conical structures appear to be analogous to the characteristic Taylor cones formed in an electrospinning process and the process is interpreted as a microscale version of electrospinning requiring significantly lower driving potentials.


A Simulation Model To Characterize Photolithography Process Of A Semiconductor Wafer Fabrication, Amr Arisha, Paul Young, Mohie El Baradie Jan 2003

A Simulation Model To Characterize Photolithography Process Of A Semiconductor Wafer Fabrication, Amr Arisha, Paul Young, Mohie El Baradie

Conference papers

The pressures on semiconductor manufacturers due to cost considerations, rapid growth of process technology, quality constraints, feature size reduction, and increasingly complex devices are increasing requiring ever higher efficiency from the manufacturing facilities. The complexity of manufacturing high capacity semiconductor devices means that it is impossible to analyze the process control parameters and the production configurations using traditional analytical models. There is, therefore, an increasing need for effective models of each manufacturing process, characterising and analyzing the process in detail, allowing the effect of changes in the production environment on the process to be predicted. The photolithography process is one …


Analyzing Algorithms & Asymptotic Notation, Dan E. Krane, Michael L. Raymer Jan 2003

Analyzing Algorithms & Asymptotic Notation, Dan E. Krane, Michael L. Raymer

Computer Science and Engineering Faculty Publications

Presentation prepared for BIO/CS 471: Algorithms for Bioinformatics. The lecture comprises material from the text Fundamental Concepts of Bioinformatics.


Santa Clara Magazine, Volume 45 Number 3, Winter 2003, Santa Clara University Jan 2003

Santa Clara Magazine, Volume 45 Number 3, Winter 2003, Santa Clara University

Santa Clara Magazine

10 - ACADEMIC EXCELLENCE AT SCU By Paul Locatelli, S.J. ln an adaptation of his convocation address, SCU 's president describes the University's goal to educate "the whole person."

12 - 'BECKHAM' BOOSTS SCU SOCCER By Victoria Hendel De La O. References to SCU in the hit movie have brought international attention to the women's soccer program.

14 - SEEKING SOLUTIONS Experts vi sit campus to discuss the issue of clergy abuse and work on a book about the topic.

18 - UNEARTHING THE PAST By Connie Skipitares. SCU archaeologists, anthropologists, and students probe a site near campus to learn …


Almeria-Mars: A Web Based Robotic Simulation, John Travis Ian Wood Jan 2003

Almeria-Mars: A Web Based Robotic Simulation, John Travis Ian Wood

Theses Digitization Project

This project discusses the concepton of a web-based simulation. In particular, it will deal with the development of a robotic Mars Pathfinder simulation delivered via the World Wide Web.


A Finite Subelement Generalization Of The Variational Nodal Method, M. A. Smith, Nicholas Tsoulfanidis, E. E. Lewis, G. Palmiotti, T. A. Taiwo Jan 2003

A Finite Subelement Generalization Of The Variational Nodal Method, M. A. Smith, Nicholas Tsoulfanidis, E. E. Lewis, G. Palmiotti, T. A. Taiwo

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

The variational nodal method is generalized by dividing each spatial node into a number of triangular finite elements designated as subelements. the finite subelement trial functions allow for explicit geometry representations within each node, thus eliminating the need for nodal homogenization. the method is implemented within the Argonne National Laboratory code VARIANT and applied to two-dimensional multigroup problems. Eigenvalue and pin-power results are presented for a four-assembly Organization for Economic Cooperation and Development/Nuclear Energy Agency benchmark problem containing enriched UO2 and mixed oxide fuel pins. Our seven-group model combines spherical or simplified spherical harmonic approximations in angle with isoparametric linear …


Bit-Level Erasure Decoding Of Reed-Solomon Codes Over Gf(2/Sup M/), T.K. Moon, Scott E. Budge Jan 2003

Bit-Level Erasure Decoding Of Reed-Solomon Codes Over Gf(2/Sup M/), T.K. Moon, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

The algorithms for bit-level erasure decoding of (n,k) Reed-Solomon codes over GF(2/sup m/) beyond the design erasure decoding distance of n-k are considered. Erasure decoding takes place in the (mk, nk) binary image code. When the number of erasures exceeds n-k, then additional parity check equations must be developed. We describe how these equations are obtained and some of their properties. Decoding algorithms are discussed which tradeoff decoding performance for computational complexity. Simulation results for several families of codes are presented which provide information about good binary image codes.


Comparing Self-Efficacy And Metacognition As Indicators Of Performance, Deborah K. Smith, Jerry Cha-Jan Chang, Trevor T. Moores Jan 2003

Comparing Self-Efficacy And Metacognition As Indicators Of Performance, Deborah K. Smith, Jerry Cha-Jan Chang, Trevor T. Moores

Management, Entrepreneurship and Technology Faculty Research

We report the results of a pilot study that compared the computer self-efficacy construct with metacognition. While self-efficacy is primarily affective and refers to one’s beliefs about one’s ability to perform a task, metacognition is primarily cognitive and refers to one’s thoughts about one’s ability to perform a task. Given their similarity, both have been used as surrogate measures of knowledge or skill. We developed an instrument to measure both constructs and applied the instrument to a set of MIS students taking an Analysis and Design course. Factor analysis produced a five-factor model, with metacognition factoring out as a unidimensional …


Evaluation Of Intra-And Inter-Fraction Motion In Breast Radiotherapy Using Electronic Portal Imaging Cine Loops, Chrison Lee, Edward Yu, Tomas Kron Jan 2003

Evaluation Of Intra-And Inter-Fraction Motion In Breast Radiotherapy Using Electronic Portal Imaging Cine Loops, Chrison Lee, Edward Yu, Tomas Kron

Oncology Presentations

Parallel tangent breast irradiation is commonly used postbreast conservation surgery for early breast cancer patient without lymph node involvement to improve local disease control. Intra-fractional and inter-fractional variabilities are often presented in daily treatment setup. The present pilot study used Electronic Portal Imaging (EPI) to evaluate intra-and inter-fraction motion in patients undergoing simple breast tangent radiotherapy.


A Discrete Dimming Ballast For Linear Fluorescent Lamps, Haiyan Wang Jan 2003

A Discrete Dimming Ballast For Linear Fluorescent Lamps, Haiyan Wang

ETD Archive

No abstract provided.


Tests 2078 & 2093: Case Ih Jx 90u Diesel, Nebraska Tractor Test Lab Jan 2003

Tests 2078 & 2093: Case Ih Jx 90u Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.


A Biologic Model For Assessment Of Osseous Strain Patterns And Plating Systems In The Human Maxilla, L. Russell Alberts, Kenneth O. Phillips, Harold K. Tu, Warren W. Stinson, Andrew Friedman Jan 2003

A Biologic Model For Assessment Of Osseous Strain Patterns And Plating Systems In The Human Maxilla, L. Russell Alberts, Kenneth O. Phillips, Harold K. Tu, Warren W. Stinson, Andrew Friedman

United States Army: Publications

Purpose: This study was conducted to examine a biomechanical model and to help answer fundamental questions that relate to rigid plate fixation in the maxilla. Specifically, we sought to elucidate the principal strain patterns generated in the maxilla secondary to masticatory forces as well as the amount of permanent deformational changes incurred due to these loading forces.
Materials and Methods: Cadaveric heads with the mandible removed were defleshed and placed in a 2-part testing rig to hold and position the skull for testing in a standard material testing system. Rosette strain gages were attached at predefined points on the skull, …


Military Leadership: A Context Specific Review, Leonard Wong, Paul Bliese, Dennis Mcgurk Jan 2003

Military Leadership: A Context Specific Review, Leonard Wong, Paul Bliese, Dennis Mcgurk

United States Army: Publications

The purpose of this article is to review the literature on military leadership and highlight research opportunities for leadership scholars. The review uses a context specific approach and turns to a simplified version of Hunt’s (Hunt, J. G. (1991). Leadership: A new synthesis. Newbury Park, California: Sage) extended multilevel leadership model as a template to examine the many facets of military leadership. The military leadership literature is stratified into the systems, organizational, and direct levels of leadership with an examination of studies on the critical tasks and individual capabilities required at each level. Additionally, studies on organizational culture and effectiveness …


The Prevalence And Severity Of Coronary Artery Calcification On Coronary Artery Computed Tomography In Black And White Subjects, Timothy C. Lee, Patrick G. O’Malley, Irwin Feuerstein, Allen J. Taylor Jan 2003

The Prevalence And Severity Of Coronary Artery Calcification On Coronary Artery Computed Tomography In Black And White Subjects, Timothy C. Lee, Patrick G. O’Malley, Irwin Feuerstein, Allen J. Taylor

United States Army: Publications

OBJECTIVES We studied the relationship between coronary artery calcium (CAC) and race in asymptomatic, active-duty personnel in the Prospective Army Coronary Calcium (PACC) project.
BACKGROUND Valid cardiovascular risk assessments in black Americans using coronary artery computed tomography (coronary CT) require the generalizability of population-based CAC score distributions derived from primarily white patient populations.
METHODS Among 1,000 consecutive participants (mean age, 42 ± 2 years; range, 40 to 45 years), 999 participants underwent coronary CT and indicated a specific racial affiliation. This included white, non-Hispanic in 699 (69.9%) participants and black, non-Hispanic in 194 (19.4%) participants. Univariate associations between race and …


History Of Food Acceptance Research In The Us Army, Herbert L. Meiselman, Howard G. Schutz Jan 2003

History Of Food Acceptance Research In The Us Army, Herbert L. Meiselman, Howard G. Schutz

United States Army: Publications

The history of food acceptance research by the US Army in Chicago and Natick is reviewed. The review covers the staff of the two research centers, the research programs, and the significant accomplishments of the Army laboratories from the 1940s to the present. Accomplishments begin with the development of the nine-point hedonic scale, and the development of the first Food Acceptance Laboratory. Further accomplishments include studies of sensory psychophysics, food preferences, food choice and food intake. The laboratories designed methods and conducted research on the role of consumer variables in the acceptance of food products and food service systems. Recent …


Rodent Sperm Analysis In Field-Based Ecological Risk Assessment: Pilot Study At Ravenna Army Ammunition Plant, Ravenna, Ohio, Lawrence V. Tannenbaum, Matthew Bazar, Melanie S. Hawkins, Barney W. Cornaby, Elizabeth A. Ferguson, L. Chantelle Carroll, Patrick F. Ryan Jan 2003

Rodent Sperm Analysis In Field-Based Ecological Risk Assessment: Pilot Study At Ravenna Army Ammunition Plant, Ravenna, Ohio, Lawrence V. Tannenbaum, Matthew Bazar, Melanie S. Hawkins, Barney W. Cornaby, Elizabeth A. Ferguson, L. Chantelle Carroll, Patrick F. Ryan

United States Army: Publications

Ecological risk assessment (ERA) guidance recommends that field-truthing efforts proceed when modeled hazard quotients (HQs) suggest that toxicological effects are occurring to site receptors. To date, no field methods have been proposed by the regulatory community that can lead to definitive determinations of acceptable or unacceptable risk for birds and mammals, the two terrestrial classes of receptors that are commonly assessed using the HQ method. This paper describes rodent sperm analysis (RSA) as a viable method to be applied in the field at sites with historical contamination. RSA is capable of detecting biological differences that bear on reproduction, a highly …


Retrieval Of Subpixel Snow-Covered Area And Grain Size From Imaging Spectrometer Data, Thomas H. Painter, Jeff Dozier, Dar A. Roberts, Robert E. Davis, Robert O. Green Jan 2003

Retrieval Of Subpixel Snow-Covered Area And Grain Size From Imaging Spectrometer Data, Thomas H. Painter, Jeff Dozier, Dar A. Roberts, Robert E. Davis, Robert O. Green

United States Army: Publications

We describe and validate an automated model that retrieves subpixel snow-covered area and effective grain size from Airborne Visible/ Infrared Imaging Spectrometer (AVIRIS) data. The model analyzes multiple endmember spectral mixtures with a spectral library of snow, vegetation, rock, and soil. We derive snow spectral endmembers of varying grain size from a radiative transfer model; spectra for vegetation, rock, and soil were collected in the field and laboratory. For three AVIRIS images of Mammoth Mountain, California that span common snow conditions for winter through spring, we validate the estimates of snow-covered area with fine-resolution aerial photographs and validate the estimates …


Simultaneous Observations Of Mesospheric Gravity Waves And Sprites Generated By A Midwestern Thunderstorm, D. D. Sentman, E. M. Wescott, R. H. Picard, J. R. Winick, H. C. Stenbaek-Nielsen, E. M. Dewan, D. R. Moudry, F. T. São Sabbas, M. J. Heavner, J. Morrill Jan 2003

Simultaneous Observations Of Mesospheric Gravity Waves And Sprites Generated By A Midwestern Thunderstorm, D. D. Sentman, E. M. Wescott, R. H. Picard, J. R. Winick, H. C. Stenbaek-Nielsen, E. M. Dewan, D. R. Moudry, F. T. São Sabbas, M. J. Heavner, J. Morrill

United States Air Force: Publications

The present report investigates using simultaneous observations of coincident gravity waves and sprites to establish an upper limit on sprite-associated thermal energy deposition in the mesosphere. The University of Alaska operated a variety of optical imagers and photometers at two ground sites in support of the NASA Sprites99 balloon campaign. One site was atop a US Forest Service lookout tower on Bear Mt. in the Black Hills, in western South Dakota. On the night of 18 August 1999 we obtained from this site simultaneous images of sprites and OH airglow modulated by gravity waves emanating from a very active sprite …


Simultaneous Observations Of Mesospheric Gravity Waves And Sprites Generated By A Midwestern Thunderstorm, D.D. Sentman, E.M. Wescott, R.H. Picard, J.R. Winick, H.C. Stenbaek-Nielsen, E.M. Dewan, D.R. Moudry, F.T. São Sabbas, M.J. Heavner, J. Morrill Jan 2003

Simultaneous Observations Of Mesospheric Gravity Waves And Sprites Generated By A Midwestern Thunderstorm, D.D. Sentman, E.M. Wescott, R.H. Picard, J.R. Winick, H.C. Stenbaek-Nielsen, E.M. Dewan, D.R. Moudry, F.T. São Sabbas, M.J. Heavner, J. Morrill

United States Department of Energy: Publications

The present report investigates using simultaneous observations of coincident gravity waves and sprites to establish an upper limit on sprite-associated thermal energy deposition in the mesosphere. The University of Alaska operated a variety of optical imagers and photometers at two ground sites in support of the NASA Sprites99 balloon campaign. One site was atop a US Forest Service lookout tower on Bear Mt. in the Black Hills, in western South Dakota. On the night of 18 August 1999 we obtained from this site simultaneous images of sprites and OH airglow modulated by gravity waves emanating from a very active sprite …


Global Optical Lightning Flash Rates Determined With The Forte Satellite, Tracy E. Light, Sean M. Davis, William Boeck, Abram Jacobson, David Suszcynsky Jan 2003

Global Optical Lightning Flash Rates Determined With The Forte Satellite, Tracy E. Light, Sean M. Davis, William Boeck, Abram Jacobson, David Suszcynsky

United States Department of Energy: Publications

Using FORTE photodiode detector (PDD) observations of lightning, we have determined the geographic distribution of nighttime flash rate density. We estimate the PDD flash detection efficiency to be 62% for total lightning through comparison to lightning observations by the TRMM satellite's Lightning Imaging Sensor (LIS), using cases in which FORTE and TRMM viewed the same storm. We present here both seasonal and total flash rate maps. We examine some characteristics of the optical emissions of lightning in both high and low flash rate environments, and find that while lightning occurs less frequently over ocean, oceanic lightning flashes are somewhat more …


Transformation Of 2-Line Ferrihydrite To 6-Line Ferrihydrite Under Oxic And Anoxic Conditions, Ravi K. Kukkadapu, John M. Zachara, James K. Fredrickson, Steven C. Smith, Alice C. Dohnalkova, Colleen K. Russel Jan 2003

Transformation Of 2-Line Ferrihydrite To 6-Line Ferrihydrite Under Oxic And Anoxic Conditions, Ravi K. Kukkadapu, John M. Zachara, James K. Fredrickson, Steven C. Smith, Alice C. Dohnalkova, Colleen K. Russel

United States Department of Energy: Publications

Mineralogical transformations of 2-line ferrihydrite were studied under oxic and Fe3+-reducing conditions to establish the role, if any, of 6-line ferrihydrite (“well” organized ferrihydrite) in the reaction pathway and as a final product. In oxic experiments, concentrated suspensions (0.42 mol/L Fe3+ in 0.1 mol/L NaClO4) of freshly synthesized 2-line ferrihydrite, with and without 3% Ni2+, were aged at an initial pH = 7.2 (unbuffered and unadjusted) and 25°C for more than three years. X-ray diffraction, transmission electron microscopy, and Mössbauer spectroscopy measurements were performed on the solids after different aging periods. The primary mineralogical products …


Microbial Reduction Of Structural Fe(Iii) In Illite And Goethite, Hailiang Dong, Ravi K. Kukkadapu, James K. Fredrickson, John M. Zachara, David W. Kennedy, Heather M. Kostandarithes Jan 2003

Microbial Reduction Of Structural Fe(Iii) In Illite And Goethite, Hailiang Dong, Ravi K. Kukkadapu, James K. Fredrickson, John M. Zachara, David W. Kennedy, Heather M. Kostandarithes

United States Department of Energy: Publications

Microbial reduction of Fe(III) in illite was studied to evaluate the possibility of microbial utilization of Fe(III) in sedimentary clays and to determine the effects of bioreduction on clay composition and structure. A subsurface bacterium (Shewanella putrefaciens CN32) and illite separates (


Mossbauer And Optical Spectroscopic Study Of Temperature And Redox Effects On Iron Local Environments In A Fe-Doped (0.5 Mol% Fe2o3)18na2o–72sio2 Glass, Ravi K. Kukkadapu, Hong Li, Gary L. Smith, J.D. Crum, Jun-Sik Jeoung, W. Howard Poisl, Michael C. Weinberg Jan 2003

Mossbauer And Optical Spectroscopic Study Of Temperature And Redox Effects On Iron Local Environments In A Fe-Doped (0.5 Mol% Fe2o3)18na2o–72sio2 Glass, Ravi K. Kukkadapu, Hong Li, Gary L. Smith, J.D. Crum, Jun-Sik Jeoung, W. Howard Poisl, Michael C. Weinberg

United States Department of Energy: Publications

Local environments of ferric and ferrous irons were systematically studied with Mössbauer (at liquid helium temperature)and ultraviolet–visible–near infrared spectroscopic methods for various 18Na2O–72SiO2 glasses doped with 0.5 mol% Fe2O3. These were prepared at temperatures of 1300–1600 °C in ambient air or at 1500 °C under reducing conditions with oxygen partial pressures from 12.3 to 0.27 x 10-7 atmospheres. The Mössbauer spectroscopic method identified three types of local environments, which were represented by the Fe3+ sextet, the Fe3+ doublet, and the Fe2+ doublet. The Fe3+ sextet ions were assigned …


Influence Of Electron Donor/Acceptor Concentrations On Hydrous Ferric Oxide (Hfo) Bioreduction, James K. Fredrickson, Sreenivas Kota, Ravi K. Kukkadapu, Chongxuan Liu, John M. Zachara Jan 2003

Influence Of Electron Donor/Acceptor Concentrations On Hydrous Ferric Oxide (Hfo) Bioreduction, James K. Fredrickson, Sreenivas Kota, Ravi K. Kukkadapu, Chongxuan Liu, John M. Zachara

United States Department of Energy: Publications

Dissimilatory metal-reducing bacteria (DMRB) facilitate the reduction of Fe and Mn oxides in anoxic soils and sediments and play an important role in the cycling of these metals and other elements such as carbon in aqueous environments. Previous studies investigating the reduction of Fe(III) oxides by DMRB focused on reactions under constant initial electron donor (lactate) and electron acceptor (Fe oxide) concentrations. Because the concentrations of these reactants can vary greatly in the environment and would be expected to influence the rate and extent of oxide reduction, the influence of variable electron acceptor and donor concentrations on hydrous ferric oxide …


Effect Of Temperature On Cs+ Sorption And Desorption In Subsurface Sediments At The Hanford Site, U.S.A., Chongxuan Liu, John M. Zachara, Odeta Qafoku, Steve Smith Jan 2003

Effect Of Temperature On Cs+ Sorption And Desorption In Subsurface Sediments At The Hanford Site, U.S.A., Chongxuan Liu, John M. Zachara, Odeta Qafoku, Steve Smith

United States Department of Energy: Publications

The effects of temperature on Cs+ sorption and desorption were investigated in subsurface sediments from the U.S. Department of Energy Hanford Site. The site has been contaminated at several locations by the accidental leakage of high-level nuclear waste (HLW) containing 137Cs+. The high temperature of the self-boiling, leaked HLW fluid and the continuous decay of various radionuclides carried by the waste supernatant have resulted in elevated vadose temperatures (currently up to 72 °C) below the Hanford S-SX tank farm that have dissipated slowly from the time of leakage (1970). The effect of temperature on Cs+ …


Nonlocal Bacterial Electron Transfer To Hematite Surfaces, Kevin Rosso, John M. Zachara, James K. Fredrickson, Yuri Gorby, Steven Smith Jan 2003

Nonlocal Bacterial Electron Transfer To Hematite Surfaces, Kevin Rosso, John M. Zachara, James K. Fredrickson, Yuri Gorby, Steven Smith

United States Department of Energy: Publications

Mechanisms by which dissimilatory iron-reducing bacteria utilize iron and manganese oxide minerals as terminal electron acceptors for respiration are poorly understood. In the absence of exogenous electron shuttle compounds, extracellular electron transfer is generally thought to occur through the interfacial contact area between mineral surfaces and attached cells. Possible alternative reduction pathways have been proposed based on the discovery of a link between an excreted quinone and dissimilatory reduction. In this study, we utilize a novel experimental approach to demonstrate that Shewanella putrefaciens reduces the surface of crystalline iron oxides at spatial locations that are distinct from points of attachment.


Transport Of Multiple Tracers In Variably Saturated Humid Region Structured Soils And Semi-Arid Region Laminated Sediments, M.A. Mayes, P.M. Jardine, T.L. Mehlhorn, B.N. Bjornstad, J.L. Ladd, John M. Zachara Jan 2003

Transport Of Multiple Tracers In Variably Saturated Humid Region Structured Soils And Semi-Arid Region Laminated Sediments, M.A. Mayes, P.M. Jardine, T.L. Mehlhorn, B.N. Bjornstad, J.L. Ladd, John M. Zachara

United States Department of Energy: Publications

The processes governing physical nonequilibrium (PNE)—coupled preferential flow and matrix diffusion—are diverse between humid and semi-arid regions, and are directly related to climate and rock/sediment type, and indirectly related to subsequent soil profile development. The fate and transport of contaminants in these variably saturated undisturbed media is largely a function of the influence of PNE processes. Large cores of laminated silts and sands were collected from the US Department of Energy Pacific Northwest National Laboratory (PNNL) in semi-arid south central Washington. Additional cores of weathered, fractured interbedded limestone and shale saprolite were collected from the Oak Ridge National Laboratory (ORNL) …


Murdock, Nebraska, Groundwater Flow And Transport Modeling In Support Of Long-Term Monitoring, Applied Geosciences And Environmental Management Section Environmental Research Division, Argonne National Laboratory Jan 2003

Murdock, Nebraska, Groundwater Flow And Transport Modeling In Support Of Long-Term Monitoring, Applied Geosciences And Environmental Management Section Environmental Research Division, Argonne National Laboratory

United States Department of Energy: Publications

Fall 2002 Assignments:
• Update all models to MODFLOW-2000
• Re-calibrate original Murdock steady-state groundwater flow model to November 25, 1998 observed water levels (Phase 1 hydrology)
• Determine time when climatological/hydrolic regime changed in eastern Nebraska. Groundwater levels observed in 2002 are significantly lower than all values observed previously (1997-1999). Palmer Hydrologic Drought Index.
• Determine appropriate groundwater level data for calibration of new (Phase 2) groundwater flow model representing current hydrologic regime (avg. of 2002 observations)
• Re-evaluate/recalculate initial CCl4 concentrations for MT3D-99 solute transport model calibration – 1996/97 concentration data. Too much CCl4 mass …


Quantitation Of Aberrant Interlocus T-Cell Receptor Rearrangements In Mouse Thymocytes And The Effect Of The Herbicide 2,4-Dichlorophenoxyacetic Acid, Geremy Knapp, R. Woodrow Setzer, James Fuscoe Jan 2003

Quantitation Of Aberrant Interlocus T-Cell Receptor Rearrangements In Mouse Thymocytes And The Effect Of The Herbicide 2,4-Dichlorophenoxyacetic Acid, Geremy Knapp, R. Woodrow Setzer, James Fuscoe

United States Environmental Protection Agency: Publications

Small studies in human populations have suggested a correlation between the frequency of errors in antigen receptor gene assembly and lymphoid malignancy risk. In particular, agricultural workers exposed to pesticides have both an increased risk for lymphoma and an increased frequency of errors in antigen receptor gene assembly. In order to further investigate the potential of such errors to serve as a mechanistically based biomarker of lymphoid cancer risk, we have developed a sensitive PCR assay for quantifying errors of V(D)J recombination in the thymocytes of mice. This assay measures interlocus rearrangements between two T-cell receptor loci, V-gamma and Jbeta, …


Quantitative Soil Descriptions For Ecoregions Of The United States, Mostafa A. Shirazi, Colleen Burch Johnson, James M. Omernik, Denis White, Patricia K. Haggerty, Glenn E. Griffith Jan 2003

Quantitative Soil Descriptions For Ecoregions Of The United States, Mostafa A. Shirazi, Colleen Burch Johnson, James M. Omernik, Denis White, Patricia K. Haggerty, Glenn E. Griffith

United States Environmental Protection Agency: Publications

Researchers have defined and mapped ecological regions of the United States based on similar patterns of ecosystems such as deserts, forests, and croplands. These studies are useful in regional research, monitoring, and environmental management because data can be more readily extrapolated within the same ecoregion and to regions with similar characteristics. The description of ecoregions is largely holistic and qualitative. Conversely, quantitative information for soil are abundant and soil is an important ecosystem component related to many ecoregion properties. We used the nationwide State Soil Geographic database(STATSGO) to describe the soils of 84 Level III ecoregions in the United States. …