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Improved Recovery Of A Radlolabeled Peptide With An Albumin-Treated Reversed-Phase Hplc Column, David S. Hage, Robert L. Taylor, Pai C. Kao Jan 1992

Improved Recovery Of A Radlolabeled Peptide With An Albumin-Treated Reversed-Phase Hplc Column, David S. Hage, Robert L. Taylor, Pai C. Kao

David Hage Publications

Reversed-phase high-performance liquid chromatography (RP-HPLC) is an important tool in the purification of radiolabeled peptides and proteins for immunoassay. However, for some proteins and peptides it is difficult to achieve reproducible behavior in RP-HPLC because of the low recovery of these compounds. Factors that can be varied to improve recovery include the strength or pH of the mobile phase, the chain length and spacing of groups on the reversed-phase support, and the flow rate or steepness of the elution gradient (1-5). ... In summary, we obtained better recovery and more reproducible chromatographic behavior for labeled 1-34 PTHrP with an albumin-pretreated …


Intact Parathyroid Hormone: Performance And Clinical Utility Of An Automated Assay Based On High-Performance Immunoaffinity Chromatography And Chemiluminescence Detection, David S. Hage, Bob Taylor, Pai C. Kao Jan 1992

Intact Parathyroid Hormone: Performance And Clinical Utility Of An Automated Assay Based On High-Performance Immunoaffinity Chromatography And Chemiluminescence Detection, David S. Hage, Bob Taylor, Pai C. Kao

David Hage Publications

The performance and clinical utility of an automated assay of intact parathyroid hormone (parathyrin, PTH) are evaluated. The method is based on the extraction of PTH from plasma by an HPLC column containing immobilized anti-(44-68 PTH) antibodies. The PTH retained is detected with a postcolumn reactor and use of anti-(1--34 PTH) chemiluminescent-labeled antibodies. The total cycle time of the assay is 6.5 mm per injection after a 1-h incubation.The lower limit of detection for PTH in a 66-pL plasma sample was 0.5 pmol/L based on peak heights and 0.2 pmol/L based on peak areas. Mean analytical recovery for PTH added …


Hydrogeologic Characterization Of A Discharge Wetland In Northeastern Grand Forks County, North Dakota, Dean R. Goebel Jan 1992

Hydrogeologic Characterization Of A Discharge Wetland In Northeastern Grand Forks County, North Dakota, Dean R. Goebel

Theses and Dissertations

Soil salinization associated with saline groundwater discharge results in decreased agricultural production in the central glacial Lake Agassiz plain of North Dakota. Saline discharge occurs in a belt of ephemeral wetlands in the lake plain. The physical and chemical hydrology of .the Lunby-stewart saline discharge wetland were investigated in order to provide information which could facilitate land management strategies applicable to this and other discharge wetlands.

Hydrologic data used to characterize the wetland were obtained from monitoring wells, staff gages, precipitation gages, borings, and earth electrical resistivity soundings. Temporal and spatial variations were observed in the water table, the vertical …


Projective And Non-Projective Systems Of First Order Nonlinear Differential Equations, Riad A. Rejoub Jan 1992

Projective And Non-Projective Systems Of First Order Nonlinear Differential Equations, Riad A. Rejoub

University of the Pacific Theses and Dissertations

It is well established that many physical and chemical phenomena such as those in chemical reaction kinetics, laser cavities, rotating fluids, and in plasmas and in solid state physics are governed by nonlinear differential equations whose solutions are of variable character and even may lack regularities. Such systems are usually first studied qualitatively by examining their temporal behavior near singular points of their phase portrait.

In this work we will be concerned with systems governed by the time evolution equations [see PDF for mathematical formulas]

The xi may generally be considered to be concentrations of species in a chemical …


Bioengineering For Water Cleanup: State-Of-The-Art Assessment, Judith L. Sims, Ronald C. Sims, Jon S. Ginn Jan 1992

Bioengineering For Water Cleanup: State-Of-The-Art Assessment, Judith L. Sims, Ronald C. Sims, Jon S. Ginn

Reports

No abstract provided.


Characterization Of Aspartic Proteinases From The Gut Of The Tick, Rhipicephalus Appendiculatus Neuman, Waha R.M. Vundla, Michel Brossard, David J. Pearson, Victor L. Labongo Jan 1992

Characterization Of Aspartic Proteinases From The Gut Of The Tick, Rhipicephalus Appendiculatus Neuman, Waha R.M. Vundla, Michel Brossard, David J. Pearson, Victor L. Labongo

All Peer-Reviewed Publications

Two proteinases designated 1 and 2, purified from the gut of partially engorged female, Rhipicephalus appendiculatus have been characterized. Both proteinases hydrolysed denatured haemoglobin (Hb) at acid pH, with Michaelis constants (KM) of 1.19 g/100 ml (proteinase 1) and 0.71 g/100 ml (proteinase 2). Pepstatin competitively inhibited both proteinases, with a K1 of 1.7 nM (proteinase 2). Both proteinases were also inhibited by 1 mM phenylmethylsulphonyl fluoride (PMSF). The pH optimum for proteinase 1 was 3.0, with a smaller but distinct second peak at pH 4.6. For proteinase 2, peak activity was at pH 2.6 with a second smaller peak …


Missing Data In Repeated Measurement Studies, Kejian Niu Jan 1992

Missing Data In Repeated Measurement Studies, Kejian Niu

Theses and Dissertations

Repeated measurement data or longitudinal data occur often in statistical applications. For example, in a clinical trial comparing the efficacy of a new treatment with that of a standard treatment, rather than measuring the main response variable only once on each patient, or subject, we can take several measurements over time on each subject.

A Repeated measurement study differs from a longitudinal study. The latter generally refers to any study in which one or more response variables are repeatedly measured over time. The former usually imposes some restrictions on the data. One common restriction is that each response variable must …


Development And Standardization Of A Short-Term Assay For Evaluating Polluted Estuarine And Coastal Environments: The Medaka Embryo-Larval Assay, Michael Frederick Helmstetter Jan 1992

Development And Standardization Of A Short-Term Assay For Evaluating Polluted Estuarine And Coastal Environments: The Medaka Embryo-Larval Assay, Michael Frederick Helmstetter

OES Theses and Dissertations

The eggs of the Japanese medaka (Oryzias latipes) were employed in a number of studies to develop a routine, standardized assay which can assess the acute and sublethal impacts of individual toxicants and complex mixtures. The eggs of this Cyprinodont minnow were topically treated with each toxicant or mixture dissolved in membrane permeable dimethylsulfoxide (DMSO) solvent. Nine chemicals were initially evaluated with two, pentachlorophenol (PCP) and tributyltin chloride (TBTCl), subsequently selected for extensive evaluations of salinity tolerance and the accuracy of the topical exposure method for representing a typical immersion exposure. The amount of material actually penetrating the eggs was …


Ontario's Blue Box As An Agent Of Change, Robert Nathaniel Burgess Jan 1992

Ontario's Blue Box As An Agent Of Change, Robert Nathaniel Burgess

Theses and Dissertations (Comprehensive)

Ontario's blue box has elicited strong arguments from observers on both sides of a debate regarding the recycling programme‘s promotion of social change in the province. Both supporters and critics agree on our eventual need to change from a consumer to a conserver society through the 3Rs of waste management (reduce. reuse. recycle). but they disagree on whether the blue box programme ultimately encourages this change. Disagreement also exists regarding the means to achieving change. With supporters of the blue box approach favouring working within the system whereas critics tend to favour a more radical approach. Practical criticisms concern the …


Practices Of Waste Management In Iowa Public Schools, Catherine Mary Patzner Jan 1992

Practices Of Waste Management In Iowa Public Schools, Catherine Mary Patzner

Dissertations and Theses @ UNI

The purpose of this study was to describe the waste management practices utilized in randomly selected Iowa public schools overall and stratified by student enrollment. The sample consisted of 100 public schools in Iowa. All public schools with enrollments of 900 or more were chosen. The remaining schools in this sample were selected based on stratified random sampling techniques. A questionnaire was constructed to ascertain the presence and extent of waste management in Iowa public schools. This questionnaire was used as the tool for collecting data. Of the 100 questionnaires mailed in this study, 76 were returned. The questionnaire was …


1-Ferrocenyl-1-Cyclopropyl Cation: The First Long-Lived Cyclopropyl Cation, G. K.Surya Prakash, Herwig Buchholz, V. Prakash Reddy, Armin De Meijere, George A. Olah Jan 1992

1-Ferrocenyl-1-Cyclopropyl Cation: The First Long-Lived Cyclopropyl Cation, G. K.Surya Prakash, Herwig Buchholz, V. Prakash Reddy, Armin De Meijere, George A. Olah

Chemistry Faculty Research & Creative Works

No abstract provided.


Empirical Procedure That Uses Molecular Structure To Predict Enantioselectivity Of Chiral Stationary Phases, Alain Berthod, San Chun Chang, Daniel W. Armstrong Jan 1992

Empirical Procedure That Uses Molecular Structure To Predict Enantioselectivity Of Chiral Stationary Phases, Alain Berthod, San Chun Chang, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

A total of 121 racemic compounds were separated In the normal-phase mode on a (S)-(1-naphthylethyl)carbamoylated β-cyclodextrin (S-NEC-β-CD) bonded phase and 74 on the R equivalent (-NEC) chiral stationary phase (CSP). All compounds are of the type that have four substituents on a stereogenlc center, rather than an "axis of chirality". It is shown that the binary solvent pair used as the mobile phase has a significant Influence on chiral recognition. However, the proportions of the components of a specific pair have little effect. From the results, the Individual contributions to chiral recognition by these CSPs were estimated for 81 different …


Towards The Development Of A Kantian Environmental Ethic, Sally Nelson Wiedmann Jan 1992

Towards The Development Of A Kantian Environmental Ethic, Sally Nelson Wiedmann

Dissertations and Theses @ UNI

This thesis is a response to Aldo Leopold's 1949 call for a new, wholistic environmental ethic. Leopold's call stemmed from his concern over the increasing degradation of the environment as a result of a utilitarian approach which judges nature as good only insofar as it is good for human economic and recreational benefit. This thesis is aimed at the development of a wholistic, non-utilitarian environmental ethic grounded in the philosophy. of Immanuel Kant. The thesis begins with a brief review of the utilitarian environmental ethic which Leopold opposed and some of the consequences it has wrought in the natural world. …


A Comparison Of The Effects Of Reading From A Vdu And From Paper As Measured In Terms Of Reading Speed And Comprehension, Elizabeth Payumo Jan 1992

A Comparison Of The Effects Of Reading From A Vdu And From Paper As Measured In Terms Of Reading Speed And Comprehension, Elizabeth Payumo

Theses: Doctorates and Masters

This study investigates the legibility and visual effects of eight combinations of font and colour on VDU and two different fonts on paper. Forty subjects, sixteen females and twenty-four males, were exposed to three of the ten different conditions, one in each of the set of readings, on either VDU or paper. They were asked to read different sets of stories in each condition on different days where each condition lasted for approximately two hours. Reading speed and comprehension scores were measured in every story read in the set of stories. The change of mood and physical symptoms states of …


Studies Of Ecological Factors That Affect The Population And Distribution Of The Western Gray Squirrel In Northcentral Oregon, Susan Ann Foster Jan 1992

Studies Of Ecological Factors That Affect The Population And Distribution Of The Western Gray Squirrel In Northcentral Oregon, Susan Ann Foster

Dissertations and Theses

The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and …


The Effects Of Oxygen Tension On Nitrate Reduction By Pseudomonas Isolate, Hao-Jan Hsing Dec 1991

The Effects Of Oxygen Tension On Nitrate Reduction By Pseudomonas Isolate, Hao-Jan Hsing

Theses

It is a generally accepted concept that nitrate reduction only occurs under anaerobic conditions. Oxygen inhibits denitrification. However many studies of nitrate reduction under low oxygen tension have shown what has been called aerobic denitrification. This project examines the process of aerobic denitrification.

Oxgyen affects cell growth and the amount of nitrate utilized. When oxygen is absent, the cell growth rate is lower and nitrate utlization is higher then when oxygen is present.

Nitrate is reduced to nirite under anaerobic conditions. Nitrite accumulation did not continue increase. But increased then decreased producing a "Z" shaped graph when plotted.


Measurement Of The Removal Of Selected Vocs From A Municipal Treatment Plant, Hong Yu Dec 1991

Measurement Of The Removal Of Selected Vocs From A Municipal Treatment Plant, Hong Yu

Theses

Industrial wastewater contains a variety of volatile chemical constituents. The large majority of the volatiles are organics. Many of these volatile or¬ganic compounds (VOCs) end up in the effluent to wastewater treatment plants. It is necessary to estimate the emission of the VOCs from sewerage plants in order to study the fate of these volatile organic compounds.

This study focuses on the estimation and comparison of the emission of 28 volatile organic compounds from the water and air in four operation units of Linden Roselle Sewerage Authority (LRSA) wastewater treatment plant. The removal rates of these target compounds have been …


User Authentication And Related Topics: An Annotated Bibliography, Eugene H. Spafford, Stephen A. Weeber Dec 1991

User Authentication And Related Topics: An Annotated Bibliography, Eugene H. Spafford, Stephen A. Weeber

Department of Computer Science Technical Reports

No abstract provided.


Resolution Of Enantiomeric Hydrocarbon Biomarkers Of Geochemical Importance, Daniel W. Armstrong, Yubing Tang, Janusz Zukowski Dec 1991

Resolution Of Enantiomeric Hydrocarbon Biomarkers Of Geochemical Importance, Daniel W. Armstrong, Yubing Tang, Janusz Zukowski

Chemistry Faculty Research & Creative Works

Chlral isoprenoid and hydroaromatic compounds occur in all crude oils, coals, shales, and most sediments. Many of these compounds are referred to as biological markers since they are thought to be derived from biological sources and their presence, relative concentrations, or stereochemistry can provide information as to a geological deposit's age, maturity, diagenetic history, and so forth. Because of the previous lack of effective and efficient analytical methodologies for resolving hydrocarbon enantiomers, the stereochemical information encoded in these molecules is largely untouched. A series of derivatized α-, β-, and γ-cyclodextrin chiral stationary phases (CSPs) were used for the gas chromatographic …


The Probe, Issue 117 - December 1991 Dec 1991

The Probe, Issue 117 - December 1991

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
DECEMBER 1991
Evaluating Performance of the Soft-Catch® Coyote Trap
Calendar of Upcoming Events
President Bush Has Unique Style Of Animal Damage Control
Soft-Catch® Traps...
Animal Damage Control in the News:
It’s the “Gull War” at Kennedy International
Cyanide Baits May Be Allowed on BLM Land
Pocket Gopher Control Evaluation at Rogue River National Forest
“USA” Today Lists Predator Protection Tips
International Resolution Supports Regulated Trapping
Over Forty NADCA Members Attend 5th Eastern Wildlife Damage Control Conference
USDA Is Helping to Limit Rabies Outbreak In Texas
Wildlife Veterinarians Adopt Position Statement on Oral Rabies …


Ccis Networking - December 1991, Nova University Dec 1991

Ccis Networking - December 1991, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.


Recycling: Knowledge, Demographic & Motivational Factors Which Differentiate Behavior, David Ducoff Dec 1991

Recycling: Knowledge, Demographic & Motivational Factors Which Differentiate Behavior, David Ducoff

Masters Theses & Specialist Projects

This study focuses on motivation -Involved in recycling behavior among residents of Muhlenberg County, Kentucky. Knowledge of recycling and how it was acquired, and the variables of environmental concern, economic incentive and the peer pressure were compared so that behavior could be distinguished that separated recyclers from nonrecyclers. Talcott Parsons' work in action theory and George Homans' work in exchange theory provide the theoretical foundation for my study. The research was approached in a qualitatively based design with interviews of twenty area residents. Demographic factors of age, sex, religious affiliation, church attendance, education and income of respondents were solicited. In …


Water Current, Volume 23, December 1991 Dec 1991

Water Current, Volume 23, December 1991

Water Current Newsletter

Massengale Presents Challenges at University Water Policy Forum
Governor Nelson Discusses Environmental Concerns at Nebraska Groundwater Foundation Luncheon
Report from the Director: Education and Research High Priorities
Surveys of Water-Related College-Education and Employment in Nebraska
California's Water Problems Explained at NGF Symposium
Cancer and Water Quality, Topic of Seminar
Wetlands Topic for 1992 Nebraska Water Conference
Environmental Cleanup Liabilities Farmers Should Consider
Eight States Evaluated in Groundwater Quality Research
Hungarian Students, Researchers to Collaborate in Environmental Degradation Studies


The Calendar - December 1991, Nova University Dec 1991

The Calendar - December 1991, Nova University

The Calendar

No abstract provided.


Environmental Radiocesium In Subarctic And Arctic Alaska Following Chernobyl, M. Baskaran, J. J. Kelley, A. S. Naidu, D. F. Holleman Dec 1991

Environmental Radiocesium In Subarctic And Arctic Alaska Following Chernobyl, M. Baskaran, J. J. Kelley, A. S. Naidu, D. F. Holleman

Environmental Science and Geology Faculty Research Publications

Radiocesium (¹³⁴ Cs and ¹³⁷ Cs) concentrations were measured in soil, plant and wildlife samples from subarctic to arctic Alaska. Concentrations of ¹³⁷ Cs ranged from below detectable or low levels in whale and fish samples to as high as 242 Bq/kg in lichen. For all potential human food items, the radiocesium concentrations measured in this study were below accepted permissible levels for human consumption. Chernobyl-derived radiocesium concentrations ranged from below detectable or low levels in all arctic samples (soil, sediment, lichen, whale, fish and caribou) to 32 Bq/kg in subarctic moss. Therefore the distribution and subsequent deposition of Chernobyl-derived …


Preliminary Epidemiological Interpretation Of The Intrinsic And Extrinsic Factors Contributing To The Coverage And Participation Rates Of The Vaccination Program In Arssi, Ethiopia, Muchie Kidanu Dec 1991

Preliminary Epidemiological Interpretation Of The Intrinsic And Extrinsic Factors Contributing To The Coverage And Participation Rates Of The Vaccination Program In Arssi, Ethiopia, Muchie Kidanu

Electronic Theses and Dissertations

Many immunization programs in developing countries arr now undergoing a period of rapid utilization. Innovative strategies, such as immunization holidays, are being tried. Political commitment and enthusiasm are high. There is a strong desire by health professionals to protect the lives of many children from the untimely death and/or disability resulting from infectious diseases preventable by vaccination.

Evaluation of an immunization program can benefit other elements of the health system, particularly those that are not amenable to objective evaluation as immunization. In this case, immunization can serve as an indicator of the overall performance of the health system. The problems …


Selected Studies On Certain Iron Sandwich Complexes, Mashitah M. Yusoff Dec 1991

Selected Studies On Certain Iron Sandwich Complexes, Mashitah M. Yusoff

Masters Theses

In these studies, the synthesis of [2.3](1,3)cyclopentadiendoparacyclophane was attempted. Like ferrocene and [2.2]paracyclophane, it is expected to exhibit transannular π-electronic interaction throughout its molecular structure and therefore, one dimensional semiconductivity.

The preparation of dialkylferrocenes had resulted in complex inseparable mixtures. Due to the fluxional nature of its intermediates, their conversion to stable Diels-Alder adducts would facilitate analysis. In this project, certain Diels-Alder adducts of bis-cyclopentadienyliron dicarbonyl intermediates were prepared for analysis.

Very few transition metal complexes of pyrrole are currently known. [2.2](2,5)Pyrroloparacyclophane was perceived to be stable especially as a part of an iron sandwich complex. The final phase …


State Of The Fisheries Report 1991, Fisheries Department Of Western Australia Dec 1991

State Of The Fisheries Report 1991, Fisheries Department Of Western Australia

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries is published annually by the Fisheries Department as part of the statutory reporting process required under the Fisheries Act. This report covers developments and production in the State's fisheries up to the end of December 1991. Full details of the department's operations for this period are published separately in the department's annual reports for the financial years ending June 1991 and 1992. Figures provided in the tables are derived from catch returns completed by fishermen which are processed by the Australian Bureau of Statistics up to June 1991. Other information provided in the text comes …


An Expert System Advisor For Medical Evaluation Boards, Jerry S. G. Harrington Dec 1991

An Expert System Advisor For Medical Evaluation Boards, Jerry S. G. Harrington

Theses and Dissertations

Expert system technology has proven itself to be able to improve productivity and decision making in a variety of fields of endeavor. The purpose of this study was to determine if an expert system for medical evaluation boards (MEBs) could improve upon the processing of medical evaluation board cases. Research was conducted to develop an expert system and measure the capabilities of the system, both in terms of accuracy and timeliness of case completion of the medical evaluation administrators/clerks who were assisted by the system. The research methodology involved a three - phase approach. The objective of phase one was …


Performance Analysis Of The Speckle Holography Image Reconstruction Technique, Rudolf N. Vonniederhausern Dec 1991

Performance Analysis Of The Speckle Holography Image Reconstruction Technique, Rudolf N. Vonniederhausern

Theses and Dissertations

In speckle holography, short exposures frames along with wave front measurements allow post processing image reconstruction. With speckle holography the amplitude of high spatial frequencies is boosted to allow resolution out to the diffraction limit of the telescope. To provide system parameters for the wave front sensor design, a software analysis program has been developed that provides the system transfer function as a function of the number and size of sensor subapertures and sensor noise. Trends in the ratio of the atmospheric coherence diameter to wave front subaperture size and the effect on the system transfer function have been obtained. …