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

Digital Commons Network™

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

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 73081 - 73110 of 78709

Full-Text Articles in Entire DC Network

Stable N-Chloraldimines And Other Chlorination Products Of Phenylalanine In Model Solutions And In A Wastewater, Barbara L. Conyers Jul 1991

Stable N-Chloraldimines And Other Chlorination Products Of Phenylalanine In Model Solutions And In A Wastewater, Barbara L. Conyers

Chemistry & Biochemistry Theses & Dissertations

Model solutions of the amino acid phenylalanine were chlorinated to seven Cl/N mole ratios. The by-products were characterized using gas chromatography, high performance liquid chromatography, GC/MS, infrared spectroscopy, and nuclear magnetic resonance spectroscopy. At the lower Cl/N ratios N-chlorophenylalanine and phenylacetaldehyde were identified as the main products while phenylacetonitrile and N-chlorophenylacetaldimine were the major products at Cl/N ratios of 2.0 and beyond. The concentration of phenylalanine in a municipal wastewater was determined. Using a radiotracer the chlorination products of phenylalanine in the wastewater at the 7 Cl/N ratios were identified as those seen in the model solutions. The distribution of …


Ua3/8/1 John Robinson Professorship Report, Wku Ogden College Of Science & Technology Jun 1991

Ua3/8/1 John Robinson Professorship Report, Wku Ogden College Of Science & Technology

WKU Administration Documents

Report by Dr. John Riley, John Robinson Professor of activities for 1990-1991 funded by Ogden Foundation.


Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes Jun 1991

Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

A fluorescent compound has been detected in proteins browned during Maillard reactions with glucose in vitro and shown to be identical to pentosidine, a pentose- derived fluorescent cross-link formed between arginine and lysine residues in collagen (Sell, D. R., and Monnier, V. M. (1989) J. Biol. Chem. 264, 21597- 2 1602). Pentosidine was the major fluorophore formed during nonenzymatic browning of ribonuclease and lysozyme by glucose, but accounted for <1% of nondisulfide cross-links in protein dimers formed during the reaction. Pentosidine was formed in greatest yields in reactions of pentoses with lysine and arginine in model systems but was also formed from glucose, fructose, ascorbate, Amadori compounds, 3-deoxyglucosone, and other sugars. Pentosidine was not formed from peroxidized polyunsaturated fatty acids or malondialdehyde. Its formation from carbohydrates was inhibited under nitrogen or anaerobic conditions and by aminoguanidine, an inhibitor of advanced glycation and browning reactions. Pentosidine was detected in human lens proteins, where its concentration increased gradually with age, but it did not exceed trace concentrations (55 Fmol/mol lysine), even in the 80-year-old lens. Although its precise carbohydrate source in vivo is uncertain and it is present in only trace concentrations in tissue proteins, pentosidine appears to be a useful biomarker for assessing cumulative damage to proteins by nonenzymatic browning reactions with carbohydrates.


Federal Regulatory Interests In Water, Patricia Sanderson Port Jun 1991

Federal Regulatory Interests In Water, Patricia Sanderson Port

Innovation in Western Water Law and Management (Summer Conference, June 5-7)

39 pages.

Contains references.


Negotiating An Indian Water Rights Settlement: The Colorado Ute Indian Experience, Lois G. Witte Jun 1991

Negotiating An Indian Water Rights Settlement: The Colorado Ute Indian Experience, Lois G. Witte

Innovation in Western Water Law and Management (Summer Conference, June 5-7)

28 pages.


Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin Jun 1991

Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin

Computer Science Technical Reports

Currently software engineering practices use relatively few formal methods. However, formal methods can be used to find errors earlier in the software cycle and hence reduce software cost. One useful formal method is program verification. The axiomatic approach to program verification uses assertions to characterize properties of program variables and relationships between them at various stages of program execution. In order to verify these assertions, axioms or inference rules are needed for each statement as well as some statement-independent inference rules. The message passing and nondeterminism of a distributed programming language present special difficulties. This paper examines and compares three …


Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin Jun 1991

Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin

Computer Science Technical Reports

Currently software engineering practices use relatively few formal methods. However, formal methods can be used to find errors earlier in the software cycle and hence reduce software cost. One useful formal method is program verification. The axiomatic approach to program verification uses assertions to characterize properties of program variables and relationships between them at various stages of program execution. In order to verify these assertions, axioms or inference rules are needed for each statement as well as some statement-independent inference rules. The message passing and nondeterminism of a distributed programming language present special difficulties. This paper examines and compares three …


Agenda: Innovation In Western Water Law And Management, University Of Colorado Boulder. Natural Resources Law Center Jun 1991

Agenda: Innovation In Western Water Law And Management, University Of Colorado Boulder. Natural Resources Law Center

Innovation in Western Water Law and Management (Summer Conference, June 5-7)

Conference organizers and/or faculty included University of Colorado School of Law professors Lawrence J. MacDonnell, David H. Getches, Charles F. Wilkinson and Richard B. Collins.

Pressures of population, drought, and changing water use have provided the impetus for numerous innovations in water law and management in recent years. The Center's annual conference June 5-7, 1991, will look at innovation and change in five areas--water planning, special water management areas, negotiated settlements of tribal water rights, conjunctive use of ground and surface water, and public values in water decision making. Each session will begin with talks by experts from several western …


The Aquatic Macroinvertebrates Of The White River National Wildlife Refuge, Steve W. Chordas Iii, George L. Harp Jun 1991

The Aquatic Macroinvertebrates Of The White River National Wildlife Refuge, Steve W. Chordas Iii, George L. Harp

Arkansas Water Resources Center Technical Reports

The primary purpose of this study was to survey the diversity of the aquatic macroinvertebrates of the White River National Wildlife Refuge (WRNWR). Determining relative abundance and distributional and seasonal patterns were secondary objectives. No comprehensive investigations of the WRNWR aquatic macroinvertebrates had been conducted previously, and it was hypothesized that this relatively undisturbed area may serve as a refugium. Further, this study provides base line data by which management programs can be composed. Thirty sampling stations were established within the WRNWR. Samples were collected from north to south at a basic rate of five stations per month. Revisit collections …


Water Quality As Affected By Pesticides In Rice Production, W. G. Johnson, T. L. Lavy, J. D. Mattice, B. W. Skulman, R. E. Talbert, R. J. Smith Jun 1991

Water Quality As Affected By Pesticides In Rice Production, W. G. Johnson, T. L. Lavy, J. D. Mattice, B. W. Skulman, R. E. Talbert, R. J. Smith

Arkansas Water Resources Center Technical Reports

Studies were conducted to determine the environmental persistence of the rice pesticides triclopyr, 2,4-D, benomyl and quinclorac. Triclopyr half-lives ranged from <7 d to >100 d depending on depth within the soil profile and clay content. Triclopyr persistence increased as depth within the profile increased and clay content increased. The benomyl metabolite MBC was present at greater than 50% of the initial amount after 9 months in the field. In simulated carryover field studies quinclorac exhibited the greatest potential for injury to subsequent rotational crops. Cotton and soybean growth was reduced when planted at four weeks after quinclorac application. The adsorption of triclopyr …


Determination Of The Abient Toxicity Of The Tailwater Of Nimrod Lake, John T. Knight Jun 1991

Determination Of The Abient Toxicity Of The Tailwater Of Nimrod Lake, John T. Knight

Arkansas Water Resources Center Technical Reports

The objective of this research was to determine if ambient toxicity exists in the receiving stream below a reservoir in which water from the hypolimnion is released. The Ceriodaphnia 7-day test was utilized to determine if toxicity existed. This test is routinely used in the monitoring of municipal and industrial effluent. It has also been utilized in determining if ambient toxicity exists within receiving streams. Nimrod Lake is a flood control impoundment on the Fourche LaFave River in west central Arkansas. The literature suggest that during stratification the hypolimnetic release contains high levels of iron, manganese, ammonia and sulfide during …


The Prairie Naturalist Volume 23, No. 2. June 1991 Jun 1991

The Prairie Naturalist Volume 23, No. 2. June 1991

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Sea bloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

CONTENTS

SMALLMOUTH BASS SIZE STRUCTURE AND CATCH RATES IN FIVE SOUTH DAKOTA LAKES AS DETERMINED FROM TWO SAMPLING GEARS ▪ C. L. Milewski and D. W. Willis

REPRODUCTION BY FISHES IN A HEADWATER STREAM FLOWING INTO GRAYROCKS RESERVOIR, WYOMING ▪ W. A. Hubert and D. T O’Shea

ENVENOMATION AND ACQUISITION OF CHEMICAL INFORMATION BY PRAIRIE RATTLESNAKES ▪ D. Chiszar, C. Hobika, H. M. Smith, and J. Vidaurri

MOVEMENTS AND HABITAT USE BY WILD TURKEY HENS WITH BROODS IN A GRASSLAND-WOODLAND MOSAIC IN THE NORTHERN …


The Probe, Issue 111 - June 1991 Jun 1991

The Probe, Issue 111 - June 1991

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
JUNE 1991
Animal Damage Control: Are We Prepared for the Next Century?
Animal Damage Control in the News
Jack Rabbit Population Fluctuates in Cyclical Patterns
Recovery Efforts for Ohio Warblers
Viscachas – New Garden Pests
Great Blue Heron Wipes Out Bass Brood Fish in Louisiana
48 Lambs Lost to Coyote Predation in Marin County, California
Measures Suggested to Prevent Gopher Damge to Underground Optic Cables
Wildlife Pamphlets to Display APHIS Logo
Rat Rodenticide Tested at DWRC, Hawaii Field Station
Prevention and Control Tips: Opossums
Registration Data Call-in For Zinc Phosphide
EPA Approves Quarterly …


Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes Jun 1991

Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes

Faculty Publications

Glycation, oxidation, and nonenzymatic browning of protein have all been implicated in the development of diabetic complications. The initial product of glycation of protein, fructoselysine (FL), undergoes further reactions, yielding a complex mixture of browning products, including the fluorescent lysine-arginine cross-link, pentosidine. Alternatively, FL may be cleaved oxidatively to form N(epsilon)-(carboxymethyl)lysine (CML), while glycated hydroxylysine, an amino-acid unique to collagen, may yield N(epsilon)-(carboxymethyl)hydroxylysine (CMhL). We have measured FL, pentosidine, fluorescence (excitation = 328 nm, emission = 378 nm), CML, and CMhL in insoluble skin collagen from 14 insulin-dependent diabetic patients before and after a 4-mo period of intensive therapy to …


Water Current, Volume 23, June 1991 Jun 1991

Water Current, Volume 23, June 1991

Water Current Newsletter

NGF Awards Received by Spaldings at Banquet
Water-Related Action in the 1991 Session of the Nebraska Legislature
From the Director: There's Good News and Bad News
Water Topics Included in New Acquisitions
Bob Volk Receives Award
All Wells in Basin Should be Regulated
News to Use
Center Pivot Industry in Nebraska Recognized with Awards
Water Quality Research Site in Nebraska Differs
More Emphasis on Water Quality Research, Federal Official
Colorado, Wyoming, Nebraska Irrigation Tour Destinations
Projects Funded Here with USGS Grants
York Recharge Project Dedicated by Dignataries and Guests
Nearly 4,500 Chemigation Applicators Certified in Two Years
Nitrate-Groundwater Contamination a …


Time Delay Neural Networks And Speech Recognition: Context Independence Of Stops In Different Vowel Environments, Gregory Andrew Makowski Jun 1991

Time Delay Neural Networks And Speech Recognition: Context Independence Of Stops In Different Vowel Environments, Gregory Andrew Makowski

Masters Theses

A series of speech recognition experiments was conducted to investigate time-dynamic speech recognition of stop consonants invariant of vowel environment using data from six talkers. The speech preprocessing was based on previous studies investigating acoustic characteristics which correlate to the place of articulation (Blumstein and Stevens 1979). The place of articulation features were statistically abstracted using four moments and the energy level of the speech sample.

Both statistical and neural network pattern recognition methods were used. Statistical methods included linear and quadratic discriminant functions, maximum likelihood estimator (MLE) and K-nearest neighbors (KNN). The neural network approach used was Time Delay …


Nonlinear Optical Properties Of Bacteriorhodopsin: Assignment Of The Third-Order Polarizability Based On Two-Photon Absorption Spectroscopy, Robert R. Birge, Mark Masthay, Jeffery A. Stuart, Jack R. Tallent, Chian-Fan Zhang Jun 1991

Nonlinear Optical Properties Of Bacteriorhodopsin: Assignment Of The Third-Order Polarizability Based On Two-Photon Absorption Spectroscopy, Robert R. Birge, Mark Masthay, Jeffery A. Stuart, Jack R. Tallent, Chian-Fan Zhang

Chemistry Faculty Publications

The third-order (pi) -electron polarizability, (gamma) (pi), of bacteriorhodopsin in the 0.0 - 1.2 eV optical region is assigned based on an analysis of the experimental two-photon properties of the low-lying singlet state manifold. The following selected values of (gamma) (pi) (units of 10-36 esu) are observed: (gamma) (0;0,0,0) equals 2482 +/- 327; (gamma) (-3(omega) ;(omega) ,(omega) ,(omega) ) equals 2976 +/- 385 ((omega) equals 0.25 eV), 5867 +/- 704 ((omega) = 0.5 eV), 14863 +/- 1614 ((omega) = 0.66 eV), 15817 +/- 2314 ((omega) equals 1.0 eV), 10755 +/- 1733 ((omega) equals 1.17 eV). The third-order polarizability of this …


The Role Of T Cells In The Pathogenesis Of Periapical Lesions, John B. Wallstrom Jun 1991

The Role Of T Cells In The Pathogenesis Of Periapical Lesions, John B. Wallstrom

Loma Linda University Electronic Theses, Dissertations & Projects

The pulps of mandibular molars of 15 athymic and 15 conventional rats were surgically exposed and left open to their oral flora. Each group was divided into 3 subgroups of 5 animals each. The rats were sacrificed after their pulps were exposed for 2, 4, or 8 weeks. After fixing, decalcifying, and embedding, the specimens were sectioned and stained with H and E. They were then examined under a microscopic grid and quantified by percentages of surface areas of bone, connective tissue, bone marrow, intrabony spaces, periapical lesions, and numbers of osteoclasts. This was done using a DataVoice computerized data …


The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman Jun 1991

The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman

Loma Linda University Electronic Theses, Dissertations & Projects

Radiation due to x-ray exposure is a concern, and the development of the Dolphin™ DigiGraph represents an attempt to limit this exposure. The purpose of this paper was to compare measurements (using Ricketts analysis) obtained from conventional radiographic cephalometric tracings with those obtained by computerized digitizing with the DigiGraph. Forty-six patients from the Loma Linda University School of Dentistry graduate orthodontic clinic were digitized, and the results were compared to the x-ray tracings of these patients. The results showed that seven of the twenty-one variables examined exhibited a statistical similarity between the two methods (DigiGraph and x-ray tracing). An examination …


Water Resources Review - June 1991 Vol 4 No 2, Annis Water Resources Institute Jun 1991

Water Resources Review - June 1991 Vol 4 No 2, Annis Water Resources Institute

AWRI Reviews

No abstract provided.


Miscellaneous Publication 17/91 - Mudas - Model Of An Uncertain Dryland Agricultural System: A Description, R. S. Kingwell, A. D. Bathgate Jun 1991

Miscellaneous Publication 17/91 - Mudas - Model Of An Uncertain Dryland Agricultural System: A Description, R. S. Kingwell, A. D. Bathgate

Farm Systems and Economics research reports

In the early 1980s, the Department of Agriculture developed a mixed integer whole-farm mathematical programming model of the dryland farming system in the eastern wheatbelt of Western Australia (Morrison et al. 1986). The model named MIDAS (Model of an Integrated Dryland Agricultural System) was constructed, tested and scrutinised by a multi-disciplinary team of researchers, advisers, farm management consultants and farmers (Kingwell 1987a). The model described in some detail the biology and finances of the dryland farming system in an average season and calculated profit-maximising farm plans.

MIDAS remains an often used tool in research and extension, being applied to many …


Biological Coal Desulfurization, Ming Le May 1991

Biological Coal Desulfurization, Ming Le

Theses

Sulfur removal from coal before combustion is of considerable interest to avoid emission of oxides of sulfur(SOx). Chemical and physical methods have been developed for removing the inorganic sulfur component in coal. This component is generally associated with pyrites(FeS2). However, no commerical methods have been developed for the removal of the organic sulfur conponent. This study describes microbial methods for removing organically bound sulfur from coal. The specific goals of this study were to ascertain whether a robust biologically active population such as activated sludge biomass can remove organic sulfur from coal and to devise sulfur analytical methods …


Isolation And Characterization Of A Crude Extracellular Phenol Oxidase From A Recirculation Bioreactor, Yun Tang May 1991

Isolation And Characterization Of A Crude Extracellular Phenol Oxidase From A Recirculation Bioreactor, Yun Tang

Theses

The study of phenol biodegradation has been performed using calcium alginate entrapped activated sludge in a recirculation reactor. An effective recirculation reactor system may be used on the laboratory scale to produce phenol oxidase, Phenol oxidase was isolated and concentrated from the degradation solution of phenol by ultrafiltration and freeze-drying respectively,

The effects of various concentrations of phenol, pH, temperature, ionic strength, cations, anions and 2- chlorophenol were studied on the oxidation reaction of enzyme. The optimal conditions of activated sludge phenol oxidase are [phenol] = 100 ppm; pH = 6.0; temperature 37°C; ionic strength equivalent to 0.1 M Na …


Experiments In Aerobic And Anaerobic Biodegradation Of Methylene Chloride Using Activated Sludge, Vivek Chandrakant Sinkar May 1991

Experiments In Aerobic And Anaerobic Biodegradation Of Methylene Chloride Using Activated Sludge, Vivek Chandrakant Sinkar

Theses

Biological removal of methylene chloride was studied under aerobic and anaerobic conditions using activated sludge cultures. Shaker flask experiments were conducted to test the ability of the microorganisms to degrade methylene chloride under aerobic conditions. Hydrogen peroxide was used a as source of dissolved oxygen to minimize physical removal of methylene chloride due to aeration. The effect of secondary substrates like glucose, cellulose acetate, ammonium acetate and nutrient broth on biodegradation of methylene chloride was studied. Biodegradation in the presence of surfactant and alkaline stress was also investigated.

No significant degradation was observed in all aerobic experiments.

Anaerobic sludge was …


Acid Recovery Of Cadmium And Lead From Immobilized Activated Sludge Used To Biosorb Metals, Chandrakanth Hartman May 1991

Acid Recovery Of Cadmium And Lead From Immobilized Activated Sludge Used To Biosorb Metals, Chandrakanth Hartman

Theses

A study of the adsorption and subsequent desorption of heavy metals using various concentrations of hydrochloric acids has been performed.

To accomplish this task, the following areas were investigated : immobilization of the sludge, adsorption of heavy metals, various concentrations of acid used as stripping agents, examination of the relative fractions of heavy metals obtained using various stripping agents, and the actual concentration of the acid at a particular fraction.

It was observed that water helps in extraction of cadmium to a certain extent, but lead cannot be extracted with water. Also, water mixed with dilute hydrochloric acid is more …


Biodegradation Of Styrene In A Recirculation Reactor Using Immobilized Activated Sludge, Shreyans Dilip Shah May 1991

Biodegradation Of Styrene In A Recirculation Reactor Using Immobilized Activated Sludge, Shreyans Dilip Shah

Theses

The performance of immobilized cells in the biological treatment of hazardous waste was investigated using a recirculating flow reactor in batch mode. A mixed culture activated sludge from a municipal waste water treatment plant was immobilized in calcium alginate gel, The bio-oxidation ability of these microbes towards a model toxin (styrene) was studied under closed system using dilute H2O2 solution as an oxygen source.
The process parameters studied were as follows:

  1. Effect of flow rate of recycle stream,
  2. Effect of biomass loading,
  3. Effect of spiking concentration of styrene, and
  4. Flow pattern and average residence time within the …


The Performance Of Training Pattern Sets In A New Art-Based Neural Architecture For Image Enhancement, Fu-Chun Chang May 1991

The Performance Of Training Pattern Sets In A New Art-Based Neural Architecture For Image Enhancement, Fu-Chun Chang

Theses

Neural network can be applied on the image enhancement after adding another two layers into the Adaptive Resonance Theory architectures (ART 1). The analysis for selecting a nice training pattern set associate the appropriate vigilance values is the main concerns in this thesis. For a single training pattern ,the network can act as a mathematical morphology operators such as erosion , dilation, opening and closing. With more than one training patterns in the network, 16 experiments are tested and are compared to each other in order to find the best selection for doing the image enhancement work. With both the …


Methods Development For Determination Of Trace Polar Volatile Organics In Environmental Samples, Qingchu Peng May 1991

Methods Development For Determination Of Trace Polar Volatile Organics In Environmental Samples, Qingchu Peng

Theses

The determination of trace levels of organic compounds in water samples is well developed for the less polar compounds, but the polar compounds are more difficult. The development of reliable and reproducible methods for such compounds as volatile alcohols and ketones is necessary if environmental monitoring is to be extended to these compounds.

The purge-and-trap method is frequently used for determination of volatiles in water samples. The method has problems when hydrophylic substances are being analyzed, since these are less easy to purge from the solution and more difficult to trap and desorb quantitatively. The high amount of water carried …


Give Saxon The Ax!, Calvin Jongsma May 1991

Give Saxon The Ax!, Calvin Jongsma

Faculty Work Comprehensive List

No abstract provided.


Cystic Fibrosis: Cluster Analysis Of Microbiology And Pulmonary Function, Lori Lee M. Larson '91 May 1991

Cystic Fibrosis: Cluster Analysis Of Microbiology And Pulmonary Function, Lori Lee M. Larson '91

Honors Projects

In an attempt to find a relationship between pulmonary infection and pulmonary function in cystic fibrosis (CF) patients, microbiology data and pulmonary function test (PFT) data for clinic patients' visits were obtained from the University of Minnesota Relational Database. The two files were merged, totaling 12,193 cases, and then analyzed using a quick cluster subroutine of SPSSX on the University of Illinois IBM Mainframe System. QUICK CLUSTER analysis showed a relationship between the virulence of the microorganisms, the amount of growth of the microorganisms, and the pulmonary function test scores of CF patients