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Comparison Between Dc-8 And Er-2 Species Measurements In The Tropical Middle Troposphere: No, NoY, O3, Co2, Ch4, And N2O, A. J. Weinheimer, D. D. Montzka, T. L. Campos, J. G. Walega, B. A. Ridley, Stephen G. Donnelly Ph.D., E. R. Keim, L. A. Del Negro, M. H. Proffitt, J. J. Margitan, K. A. Boering, A. E. Andrews, B. C. Daube, S. C. Wofsy, B. E. Anderson, J. E. Collins, G. W. Sachse, S. A. Vay, J. W. Elkins, P. R. Wamsley, E. L. Atlas, F. Flocke, S. Schauffler, C. R. Webster, R. D. May, M. Loewenstein, J. R. Podolske, T. P. Bui, K. R. Chan, S. W. Bowen, M. R. Schoeberl, L. R. Lait Sep 1998

Comparison Between Dc-8 And Er-2 Species Measurements In The Tropical Middle Troposphere: No, NoY, O3, Co2, Ch4, And N2O, A. J. Weinheimer, D. D. Montzka, T. L. Campos, J. G. Walega, B. A. Ridley, Stephen G. Donnelly Ph.D., E. R. Keim, L. A. Del Negro, M. H. Proffitt, J. J. Margitan, K. A. Boering, A. E. Andrews, B. C. Daube, S. C. Wofsy, B. E. Anderson, J. E. Collins, G. W. Sachse, S. A. Vay, J. W. Elkins, P. R. Wamsley, E. L. Atlas, F. Flocke, S. Schauffler, C. R. Webster, R. D. May, M. Loewenstein, J. R. Podolske, T. P. Bui, K. R. Chan, S. W. Bowen, M. R. Schoeberl, L. R. Lait

Chemistry Faculty Publications

We compare measurements of six species taken aboard NASA DC-8 and ER-2 aircraft during two flight legs in the tropical middle troposphere near Hawaii. NO, NOy, O3, CH4, and N2O measurements agree to within the limits set by the known systematic errors. For CO2, which can be measured with better relative precision than the other five species, differences in measured values from the two platforms are slightly larger than expected if the air masses sampled by the two aircraft were indeed similar in CO2 composition to better than 0.08%. Copyright 1998 by the American Geophysical Union.


Simultaneous Formation Of Functional Leading And Lagging Strand Holoenzyme Complexes On A Small, Defined Dna Substrate, Anthony J. Berdis, Stephen J. Benkovic Sep 1998

Simultaneous Formation Of Functional Leading And Lagging Strand Holoenzyme Complexes On A Small, Defined Dna Substrate, Anthony J. Berdis, Stephen J. Benkovic

Chemistry Faculty Publications

The biochemical characterization of leading and lagging strand DNA synthesis by bacteriophage T4 replication proteins has been addressed utilizing a small, defined primer/template. The ATP hydrolysis activity of 44/62, the clamp loading complex responsible for holoenzyme assembly, was monitored during assembly of both the leading and lagging strand holoenzyme complex. The ATPase activity of 44/62 diminishes once a functional holoenzyme is assembled on both the leading and lagging strand. The assembly of the lagging strand holoenzyme is facilitated by several factors including biotinylated streptavidin blocks at the end of the fork strands, preassembly of the leading strand holoenzyme, and by …


Chemical Signals From Submarine Fluid Advection Onto The Continental Shelf, W. S. Moore, Timothy J. Shaw Sep 1998

Chemical Signals From Submarine Fluid Advection Onto The Continental Shelf, W. S. Moore, Timothy J. Shaw

Faculty Publications

No abstract provided.


Table Of Contents Volume Nine, Number Four, Fall 1998, Risk Editorial Board Sep 1998

Table Of Contents Volume Nine, Number Four, Fall 1998, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal RISK: Health, Safety & Environment (ISSN: 1073-8673)


Track Structure Model For Radial Distributions Of Electron Spectra And Event Spectra From High-Energy Ions, F. A. Cucinotta, Robert Katz, J. W. Wilson Sep 1998

Track Structure Model For Radial Distributions Of Electron Spectra And Event Spectra From High-Energy Ions, F. A. Cucinotta, Robert Katz, J. W. Wilson

Robert Katz Publications

An analytic method is described for evaluating the average radial electron spectrum and the radial and total frequency-event spectrum for high-energy ions. For high-energy ions, indirect events make important contributions to frequency-event spectra. The method used for evaluating indirect events is to fold the radial electron spectrum with measured frequency-event spectrum for photons or electrons. The contribution from direct events is treated using a spatially restricted linear energy transfer (LET). We find that high-energy heavy ions have a significantly reduced frequency-averaged lineal energy (YF) compared to LET, while relativistic protons have a significantly increased YF and dose-averaged lineal energy (YD) …


Ecological Evaluation For The West Ash Creek Potential Research Natural Area, Pine Ridge Ranger Unit, Nebraska National Forest, Steven B. Rolfsmeier Sep 1998

Ecological Evaluation For The West Ash Creek Potential Research Natural Area, Pine Ridge Ranger Unit, Nebraska National Forest, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The West Ash Creek Potential Research Natural Area is located within pastures 6, 7, and 11 of the Pine Ridge Unit of the Nebraska National Forest ca 18 mi. (30 km) southwest of Chadron, Nebraska. The area consists of ca 1020 acres of mostly successional pine forest burned in a 1985 wildfire, with unburned forest, some grassland, and riparian canyon bottoms. The area is within the Pine Ridge ecosystem of the White River watershed in northwestern Nebraska. The area has remained ungrazed nearly continuously since 1986.

This document was prepared to provide the Forest Service with information to determine the …


Quality Of Surface And Ground Water And Best Management Practices, Kenneth F. Steele Sep 1998

Quality Of Surface And Ground Water And Best Management Practices, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

Arkansas is fortunate to have outstanding water resources, especially in terms of water quality. However, this is not to say that there are no problems. The Arkansas Water Resources Center (AWRC) in cooperation with other state and federal agencies is characterizing our water resources and providing data important to the wise use of these resources. One wise use of our water resources is to mitigate the impact of non-point sources of pollution on water quality through the use of best management practices. These proceedings address not only the characterization of the quality of ground and surface water but also address …


The Probe, Issue 192 – September 1998 Sep 1998

The Probe, Issue 192 – September 1998

The Probe: Newsletter of the National Animal Damage Control Association

The Role of "Preventive Control" in Coyote Damage Management -- Mark Collinge, NADCA Vice-President
NADCA Member Has Syndicated Wildlife Column -- Andrea Kitay, Camarillo, California
Promoting Barn Owls to Control Rodents is Deception -- Rex E. Marsh
TWS Response to NADCA Proposal for Certification
Position Announcement: Wildlife-Communications Specialist, DEPARTMENT OF NATURAL RESOURCES, NEW YORK STATE COLLEGE OF AGRICULTURE AND LIFE SCIENCES, CORNELL UNIVERSITY
Plague Found in Captive Texas Prairie Dogs


Directory Of Water Related Courses Offered At Colleges And Universities In Arkansas As Of November 1998, Kenneth F. Steele Sep 1998

Directory Of Water Related Courses Offered At Colleges And Universities In Arkansas As Of November 1998, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

This publication lists the water and water-related courses at several universities and colleges in Arkansas as reported during the Fall of 1 998. It is anticipated that users of this directory will extend beyond college students, and will include professionals seeking continuing education, and professors desiring to exchange Information on courses. This directory is not an "absolute" source of water and water-related courses because all of the higher learning Institutions In Arkansas are not listed, and, secondly, because the definition of "water and water-related" varies from institution to institution. None-the-less this directory provides a very valuable and impressive reference on …


Final Report: Future Management Of The Aquatic Charter Industry In Western Australia., Tour Operators Fishing Working Group Sep 1998

Final Report: Future Management Of The Aquatic Charter Industry In Western Australia., Tour Operators Fishing Working Group

Fisheries Management Papers

The Tour Operator's Fishing Working Group (TOFWG) was established by the Hon Monty House MLA, Minister for Fisheries, in recognition of the growing importance of this element of the tourism industy and in recognition of the need to ensure that the development of this industry occurs in an ecologically sustainable framework across the Sate. The recommendations outlined in this report establish a management framework within which the aquatic charter industry may continue to develop, and which will ensure the long-term sustainability of the natural resources on which the industry is based.


Mesures Directes Et Modélisation De La Croissance Rapide D'Un Crinoïde Pédonculé Bathyal Au Large Des Bahamas (Direct Measurement And Inferred Model Of Rapid Growth In A Bathyal Stalked Crinoid From Bahamas Islands), Jérôme David, Charles G. Messing, Tomasz K. Baumiller, Nadia Améziane, Michel Roux Sep 1998

Mesures Directes Et Modélisation De La Croissance Rapide D'Un Crinoïde Pédonculé Bathyal Au Large Des Bahamas (Direct Measurement And Inferred Model Of Rapid Growth In A Bathyal Stalked Crinoid From Bahamas Islands), Jérôme David, Charles G. Messing, Tomasz K. Baumiller, Nadia Améziane, Michel Roux

Marine & Environmental Sciences Faculty Articles

Several specimens of the isocrinid crinoid Neocrinus decorus were collected from a depth of 420 m off Bahamas Islands with the research submersible Johnson Sea Link. To study growth rates, these specimens were tagged, deployed and then recovered 250 days later. The average growth rate of stalk length is 10.8 cm.year−1 with a maximum value at 14.3 cm.year−1. These results allow us to propose a model of growth and regeneration for stalked crinoids in which the energy allocation is modulated through time to the arms and the stalk. Following arm autotomy, in order to re-establish optimum filtration …


The Prairie Naturalist Volume 30, No. 3 September 1998 Sep 1998

The Prairie Naturalist Volume 30, No. 3 September 1998

The Prairie Naturalist

GROWTH OF SPOTIED BASS IN KANSAS STREAMS AND IMPOUNDMENTS ▪ J. S. Tillma and C. S. Guy

SIZE SELECTION OF RAINBOW SMELT BY SMALL MESH GILL NETS ▪ C. E. Freiburger and W. G. Duffy

ABUNDANCE AND HABITAT AFFINITIES OF Cyclotracheius substriatus (Coleoptera: Carabidae) ON NORTHERN SHORTGRASS PRAIRIE ▪ N. E. Mcintyre 157

THE REPRODUCTIVE BIOLOGY OF CANDLE ANEMONE ▪ B. Molano-Flores and S. D. Hendrix

NOTES

Noteworthy Records of Bats from Southern Colorado ▪ E. W. Valdez

Eggshell Removal by Duck Hens Following

Partial Nest Depredation by Striped Skunk ▪ S. Lariviere and L. R. Walton

New Records of …


Center For Sustainable Agricultural Systems Newsletter, September/October 1998 Sep 1998

Center For Sustainable Agricultural Systems Newsletter, September/October 1998

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Contents:

A Broader View and Challenge for the CSAS

Highlights of Upcoming New Book: Under the Blade (Part 3)

Integrated Farm Update: Will Grazing Crop Residues Hurt Next Year's Yields?

Honeybee Populations Lowest Levels in Decade

Socrates Network in Europe

New Course: Urbanization of Rural Landscapes, Offered Spring Semester


Immunological Relationship Between The Class I Epitope Of Streptococcal M Protein And Myosin, Anthony Quinn, Kent Ward, Vincent A. Fischetti, Mark E. Hemric, Medeleine W. Cunningham Sep 1998

Immunological Relationship Between The Class I Epitope Of Streptococcal M Protein And Myosin, Anthony Quinn, Kent Ward, Vincent A. Fischetti, Mark E. Hemric, Medeleine W. Cunningham

Faculty Publications and Presentations

The class I epitope of streptococcal M protein is an epidemiological marker for acute rheumatic fever (ARF)-associated serotypes of group A streptococci and is recognized by anti-M protein monoclonal antibody (MAb) 10B6. Using MAb 10B6, we determined the relationship between the class I epitope of M protein and the a-helical coiled-coil protein myosin. MAb 10B6 reacted by enzyme-linked immunosorbent assay and Western blotting with human cardiac myosin and rabbit skeletal myosin and its heavy meromyosin (HMM) subfragment. Overlapping synthetic peptides of M5 protein were used to identify the region of M5 protein recognized by MAb 10B6. Two C repeat peptides …


Response Of Runoff Diazinon Concentration To Formulation And Post-Application Irrigation, Joshua R. Evans, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams Sep 1998

Response Of Runoff Diazinon Concentration To Formulation And Post-Application Irrigation, Joshua R. Evans, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams

Biosystems and Agricultural Engineering Faculty Publications

Pesticides used in urban environments can be transported in runoff to downstream waters and cause adverse environmental consequences. This experiment assessed the effects of post-application irrigation depth (0, 6.4, and 12.7 mm) and formulation (liquid and granular) on concentration and transport of diazinon (a pesticide commonly used for lawn insect control) in runoff from “tall” fescue (Festuca arundinacea Schreb.) plots. The post-application irrigation was applied using rainfall simulators immediately following diazinon application. The rainfall simulators were again used approximately 2 h after diazinon application to apply the equivalent of a heavy rainfall (64 mm/h for approximately 1.5 h) to generate …


Application Of Mathematical Modeling And Computer Simulation For Solving Water Quality Problems, Jacek Makinia, Scott A. Wells, David Crawford, Marian Kulbik Sep 1998

Application Of Mathematical Modeling And Computer Simulation For Solving Water Quality Problems, Jacek Makinia, Scott A. Wells, David Crawford, Marian Kulbik

Civil and Environmental Engineering Faculty Publications and Presentations

Deteriorated water resources in Central and Eastern Europe call for actions that should be undertaken to improve current conditions and to protect human and environmental health. Mathematical modeling and computer simulation is often an integral part of the decision-making process. Models and simulations allow rapid and varied evaluation of causes and effects and the principal advantage is that they enable an analysis of even long-term actions with limited investment costs. This paper provides an overview of popular models used for simulation of major elements of a water quality system: surface water quality (QUAL2E), wastewater treatment (Activated Sludge Model No.1), sewer …


Average Profile Of The Lempel-Ziv Parsing Scheme For Markovian Source, Philippe Jacquet, Wojciech Szpankowski, Jing Tang Sep 1998

Average Profile Of The Lempel-Ziv Parsing Scheme For Markovian Source, Philippe Jacquet, Wojciech Szpankowski, Jing Tang

Department of Computer Science Technical Reports

No abstract provided.


Effects Of N-Acetylcysteine And 2,3-Dimercaptosuccinic Acid On Lead Induced Oxidative Stress In Rat Lenses, Rachel Neal, Katherine Cooper, Nuran Ercal, Hande Gürer-Orhan Sep 1998

Effects Of N-Acetylcysteine And 2,3-Dimercaptosuccinic Acid On Lead Induced Oxidative Stress In Rat Lenses, Rachel Neal, Katherine Cooper, Nuran Ercal, Hande Gürer-Orhan

Chemistry Faculty Research & Creative Works

Lead (Pb) is known to disrupt the pro-oxidant/anti-oxidant balance of tissues which leads to biochemical and physiological dysfunction. The present study investigated the previous termeffectsnext term of exposure on the redox status of the lenses of Fisher 344 rats and examined whether antioxidant or chelator administration reversed these changes. Animals were given 5 weeks of 2000 ppm Pb exposure followed by 1 week of either antioxidant, chelator or distilled water administration. Glutathione (GSH) and cysteine (CYS) levels decreased in the Pb-exposed group. N-previous termacetylcysteinenext term or 2,3-dimercaptopsuccinic previous termacidnext term (Succimer) supplementation following Pb intoxication resulted in increases in the …


Localization Of Sodium, Potassium-Adenosine Triphosphatase In The Cerebral Cortex Of Developing Rats, Maki Ujiie Sep 1998

Localization Of Sodium, Potassium-Adenosine Triphosphatase In The Cerebral Cortex Of Developing Rats, Maki Ujiie

Loma Linda University Electronic Theses, Dissertations & Projects

Active transport via Na+, K+-ATPase plays an important role in establishing and maintaining proper ionic gradient across all mammalian cell membranes. A strict regulation of Na+, and K+ ion levels is especially important in excitable cells such as neurons and myocytes. Inhibition of the enzyme is associated with several pathological conditions and has serious detrimental effects on cerebral cortical cells. Yet the enzyme appears to be limited in amount and distribution in newborn rats. In this study, Na+, K+- ATPase expression and distribution in early postnatal rats were studied …


Protein Fragmentation Due To Slow Highly Charged Ion Impact, Christiane Ruehlicke, Dieter Schneider, Markus Schneider, Robert D. Dubois, Rod Balhorn Sep 1998

Protein Fragmentation Due To Slow Highly Charged Ion Impact, Christiane Ruehlicke, Dieter Schneider, Markus Schneider, Robert D. Dubois, Rod Balhorn

Physics Faculty Research & Creative Works

We present first results of experiments on the fragmentation of biomolecules using highly charged heavy ions. Fragmentation and modification of oligopeptides, such as dimerization and attachment of ionic salt components, have been observed by means of mass spectrometry. Plasmid DNA molecules were imaged with an atomic force microscope after ion irradiation and profound molecular damage was found.


Direct Voltammetric Observation Of Redox Driven Changes In Axial Coordination And Intramolecular Rearrangement Of The Phenylalanine-82-Histidine Variant Of Yeast Iso-1-Cytochrome C, Benjamin A. Feinberg, Xiangjun Liu, Michael D. Ryan, Abel Schejter, Chongyao Zhang, Emanuel Margoliash Sep 1998

Direct Voltammetric Observation Of Redox Driven Changes In Axial Coordination And Intramolecular Rearrangement Of The Phenylalanine-82-Histidine Variant Of Yeast Iso-1-Cytochrome C, Benjamin A. Feinberg, Xiangjun Liu, Michael D. Ryan, Abel Schejter, Chongyao Zhang, Emanuel Margoliash

Chemistry Faculty Research and Publications

Direct square-wave and cyclic voltammetric electrochemical examination of the yeast iso-1-cytochrome c Phe82His/Cys102Ser variant revealed the intricacies of redox driven changes in axial coordination, concomitant with intramolecular rearrangement. Electrochemical methods are ideally suited for such a redox study, since they provide a direct and quantitative visualization of specific dynamic events. For the iso-1-cytochrome c Phe82His/Cys102Ser variant, square-wave voltammetry showed that the primary species in the reduced state is the Met80-Fe2+-His18 coordination form, while in the oxidized state the His82-Fe3+-His18 form predominates. The addition or removal of an electron to the …


Radial Distribution Of Electron Spectra From High-Energy Ions, Francis A. Cucinotta, Robert Katz, John W. Wilson Sep 1998

Radial Distribution Of Electron Spectra From High-Energy Ions, Francis A. Cucinotta, Robert Katz, John W. Wilson

Robert Katz Publications

The average track model describes the response of physical and biological systems using radial dose distribution as the key physical descriptor. We report on an extension of this model to describe the average distribution of electron spectra as a function of radial distance from an ion. We present calculations of these spectra for ions of identical linear energy transfer (LET), but dissimilar charge and velocity to evaluate the differences in electron spectra from these ions. To illustrate the usefulness of the radial electron spectra for describing effects that are not described by electron dose, we consider the evaluation of the …


Supercritical Fluid Extraction (Sfe) And High Performance Liquid Chromotography (Hplc) Analysis Of Polycyclic Aromatic Hydrocarbon (Pah) Contaminated Soil, Marie Renee Gargas Aug 1998

Supercritical Fluid Extraction (Sfe) And High Performance Liquid Chromotography (Hplc) Analysis Of Polycyclic Aromatic Hydrocarbon (Pah) Contaminated Soil, Marie Renee Gargas

Theses

Methods for the extraction and analysis of polycyclic aromatic hydrocarbons (PAHs) from contaminated soil were evaluated for use in a treatability study. Candidate procedures were selected from EPA SW-846 (Third Edition) methods. Soxhlet extraction (3540B) was selected to determine initial PAH concentrations. Supercritical fluid extraction with carbon dioxide (SFE: 3561) and high performance liquid chromatography (HPLC: 8310) were evaluated for use as the extraction and analysis methods. Experimental soil was obtained from a petroleum product refinery site; a Certified Reference Material (CRM) was also studied.

Experiments focused on determining concentrations of anthracene, chrysene, fluoranthene, phenanthrene, and pyrene in untreated experimental …


Determination Of Electron Donors In The Reductive Dechlorination Of Tetrachloroethene, Samantha L. Marasigan-Bernal Aug 1998

Determination Of Electron Donors In The Reductive Dechlorination Of Tetrachloroethene, Samantha L. Marasigan-Bernal

Theses

Several substrates, namely fatty acids and alcohols, were used to enhance the reductive microbial dechlorination of PCE to ethene. All of the microcosms amended with the volatile fatty acids (butyrate, succinate, lactate, formate, butyrate/formate mixture and butyrate/succinate mixture) demonstrated complete reductive dechlorination of PCE to ethane. The cultures amended with the butyrate/succinate mixture was the quickest to completely dechlorinate PCE to ethene (49 days). Those amended with butyrate, succinate, formate and the butyrate/formate mixture exhibited complete reductive, dechlorination at 77 days. Microcosms amended with lactate exhibited complete reductive dechlorination at 160 days.

The microcosms amended with the alcohols (ethanol, propanol, …


The Feasibility Of Transferring Clean Technology From The United States To China : A Case Study From The Paper Industry, He Ning Aug 1998

The Feasibility Of Transferring Clean Technology From The United States To China : A Case Study From The Paper Industry, He Ning

Theses

In their pursuit of economic development, many developing countries are causing pollution at an alarming rate. One solution to the problem is the use of clean technology. Some developed countries have created various manufacture technologies which result in pollution prevention. There is a need for the transfer of clean technology from the developed countries to developing countries. It is beneficial to study the feasibility of such transfer.

The manufacturing processes of the paper industry are selected for this study. An investigation and comparison was conducted in order to evaluate the feasibility of clean technology transfer from the United States to …


Applications Of Parallel I/O, Ron Oldfield, David Kotz Aug 1998

Applications Of Parallel I/O, Ron Oldfield, David Kotz

Computer Science Technical Reports

Scientific applications are increasingly being implemented on massively parallel supercomputers. Many of these applications have intense I/O demands, as well as massive computational requirements. This paper is essentially an annotated bibliography of papers and other sources of information about scientific applications using parallel I/O. It will be updated periodically.


Detergent-Salt Resistance Of Lap2Α In Interphase Nuclei And Phosphorylation-Dependent Association With Chromosomes Early In Nuclear Assembly Implies Functions In Nuclear Structure Dynamics, Thomas Dechat, Josef Gotzmann, Andreas Stockinger, Crafford A. Harris, Mary Ann Talle, John Siekierka, Roland Foisner Aug 1998

Detergent-Salt Resistance Of Lap2Α In Interphase Nuclei And Phosphorylation-Dependent Association With Chromosomes Early In Nuclear Assembly Implies Functions In Nuclear Structure Dynamics, Thomas Dechat, Josef Gotzmann, Andreas Stockinger, Crafford A. Harris, Mary Ann Talle, John Siekierka, Roland Foisner

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Lamina-associated polypeptide (LAP) 2 of the inner nuclear membrane (now LAP2β) and LAP2α are related proteins produced by alternative splicing, and contain a common 187 amino acid N-terminal domain. We show here that, unlike LAP2β, LAP2α behaved like a nuclear non-membrane protein in subcellular fractionation studies and was localized throughout the nuclear interior in interphase cells. It co-fractionated with LAP2β in nuclear lamina/matrix-enriched fractions upon extraction of nuclei with detergent, salt and nucleases. During metaphase LAP2α dissociated from chromosomes and became concentrated around the spindle poles. Furthermore, LAP2α was mitotically phosphorylated, and phosphorylation correlated with increased LAP2α solubility upon extraction …


Production Of Energy-Dependent Time Delays In Impulsive Solar Flare Hard X-Ray Emission By Short-Duration Spectral Index Variations, Ted N. La Rosa, Steven N. Shore Aug 1998

Production Of Energy-Dependent Time Delays In Impulsive Solar Flare Hard X-Ray Emission By Short-Duration Spectral Index Variations, Ted N. La Rosa, Steven N. Shore

Faculty Articles

Cross-correlation techniques have been used recently to study the relative timing of solar flare hard X-ray emission at different energies. These studies find that for the majority of the impulsive flares observed with BATSE there is a systematic time delay of a few tens of milliseconds between low (approximate to 50 keV) and higher energy emission (approximate to 100 keV). These time delays have been interpreted as energy-dependent time-of-flight differences for electron propagation from the corona, where they are accelerated, to the chromosphere, where the bulk of the hard X-rays are emitted. We show in this paper that crosscorrelation methods …


Highly Enantioselective Hplc Separations Using The Covalently Bonded Macrocyclic Antibiotic, Ristocetin A, Chiral Stationary Phase, K. Helen Ekborg-Ott, Youbang Liu, Daniel W. Armstrong Aug 1998

Highly Enantioselective Hplc Separations Using The Covalently Bonded Macrocyclic Antibiotic, Ristocetin A, Chiral Stationary Phase, K. Helen Ekborg-Ott, Youbang Liu, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

The macrocyclic glycopeptide, ristocetin A, was covalently bonded to a silica gel support and evaluated as a liquid chromatographic (LC) chiral stationary phase (CSP). Over 230 racemates were resolved in either the reversed-phase mode, the normal-phase mode, or the polar-organic mode. The retention behavior and selectivity of this CSP were examined in each mode. Optimization of separations on this column is discussed. The ristocetin A CSP appeared to be complimentary to other glycopeptide CSPs (i.e., vancomycin and teicoplanin). Column stability was excellent. The CSP was not irreversibly altered when going from one mobile phase mode to another.


Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith Aug 1998

Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith

AAES Research Reports and Research Bulletins

Agriculture is the largest use of soil and water resources in eastern Arkansas. This bulletin summarized the recent historical use of soil and water by agriculture and the impact of irrigation on yields of rice, soybeans and cotton. The experiments conducted in the field to quantitatively schedule irrigations of crops are summarized. The results show the close relationship between the irrigation of crops and the extraction of water from the Alluvial Aquifer. The implications of this relationaship for the future are discussed.