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Thermodynamic Data From Drug-Dna Footprinting Experiments, James C. Dabrowiak, Jerry Goodisman, Koren Kissinger Apr 1990

Thermodynamic Data From Drug-Dna Footprinting Experiments, James C. Dabrowiak, Jerry Goodisman, Koren Kissinger

Chemistry - All Scholarship

Sequence-dependent thermodynamic quantities for the antiviral agent netropsin and a related bis(N-methylimidazole) dipeptide, lexitropsin, have been determined by DNase I footprinting techniques. The primary data are autoradiographic spot intensities derived from 10 footprinting experiments carried out in the temperature range 0-45 OC. After exclusion effects due to overlapped drug sites on DNA and redistribution phenomena associated with the enzyme were accounted for, sequence-dependent binding constants for the two ligands were calculated. Our approach does not require an independent determination of the free drug concentration, which is calculated, with individual site binding constants, by using only footprinting data. The temperature dependence …


The Role Of The Voltage Gradient In The Agarose Gel Electrophoresis Of Dna, David Wheeler Apr 1990

The Role Of The Voltage Gradient In The Agarose Gel Electrophoresis Of Dna, David Wheeler

Theses and Dissertations in Biomedical Sciences

In Part I of this dissertation, empirical equations for predicting DNA mobility during agarose gel electrophoresis (AGE) from voltage gradient are developed from the data of McDonnel (36) for electrophoresis in a 1.6% agarose gel. These equations represented the data well for DNA between 2 and 10 kilobase pairs (KBp) in length. A computer program, called GELSIM, which incorporates these equations is described in Part II. GELSIM was designed to allow researchers to analyze electrophoresis data by predicting the effect on DNA migration of altering the voltage of electrophoresis. In this way, electrophoretic banding patterns produced using different voltages could …


Kinetics Of The Metal-Exchange Reaction Between Ortho-Phospho-Dl -Serinenickelate(Ii) And Copper(Ii), Jeffrey M. Peterman Apr 1990

Kinetics Of The Metal-Exchange Reaction Between Ortho-Phospho-Dl -Serinenickelate(Ii) And Copper(Ii), Jeffrey M. Peterman

Masters Theses

No abstract provided.


Chloroplast And Mitochondrial: Dna Polymerases From Cultured Soybean Cells, Sabine Heinhorst, Gordon C. Cannon, Arthur Weissbach Apr 1990

Chloroplast And Mitochondrial: Dna Polymerases From Cultured Soybean Cells, Sabine Heinhorst, Gordon C. Cannon, Arthur Weissbach

Faculty Publications

DNA polymerases were purified from chloroplasts and mitochondria of cultured Glycine max cells. The chloroplast enzyme exists in two forms which are indistinguishable from each other biochemically. All three organellar enzymes have an estimated molecular weight of 85,000 to 90,000 and prefer poly(rA)dT12-18 over activated DNA as a template in vitro. Maximum activity of the chloroplast and mitochondrial DNA polymerases requires KCI and a reducing agent, and the enzymes are completely resistant to inhibitors of DNA polymerase a. Taken together, these properties classify the soybean organellar enzymes as DNA polymerases y. A unique feature that distinguishes the plant enzymes from …


Studies Of Nitro-Pah On Ambient Air Particulate Matter, Yadan Wang Chen Jan 1990

Studies Of Nitro-Pah On Ambient Air Particulate Matter, Yadan Wang Chen

Theses

A rapid, simple method for routine trace analysis of four isomeric nitropolycyclic aromatic hydrocarbons (nitro-PAH) (1-nitropyrene, 2-nitropyrene, 2-nitrofluoranthene and 3-nitrofluoranthene) in ambient air particulate matter is described. Two types of air particle sample (TSP and IP10) were collected and particle extracts were prefractionated by thin layer chromatography and the appropriate zones of interest analyzed by reversed-phase HPLC with UV and fluorescence detection. The study of Zn/Si post-column reaction chamber and oxygen scrubber for catalytic reduction of target compounds is also described. Six nitro-PAH compounds were identified in TSP and five in IP10 air particle samples. The results of identification and …


Pleiochaeta Diseases Of Lupins, Mark Sweetingham Jan 1990

Pleiochaeta Diseases Of Lupins, Mark Sweetingham

Experimental Summaries - Plant Research

Trial 90WH20, 90SC5, 90LG8

Rates of dicarboximide fungicides for lupins.

Location: Wongan Hills Research Station, South Carrabin Research Station, East Hyden.

To compare the disease control and yield response of Rovral and Sumisclex seed treatments at a range of rates.

Trial 90M11, 90BA17

Rates of dicarboxide fungicides for lupins.

Location: Merredin Research Station, Badgingarra Research Station.

To compare the disease control and yield response of Rovral and Sumisclex seed treatments at a range of rates,


Isoprenylation Is Required For The Processing Of The Lamin A Precursor, Michael Sinensky, L. A. Beck, T. J. Hosick Jan 1990

Isoprenylation Is Required For The Processing Of The Lamin A Precursor, Michael Sinensky, L. A. Beck, T. J. Hosick

Faculty Publications, Biological Sciences

The nuclear lamina proteins, prelamin A, lamin B, and a 70-kD lamina-associated protein, are posttranslationally modified by a metabolite derived from mevalonate. This modification can be inhibited by treatment with (3-R,S)-3-fluoromevalonate, demonstrating that it is isoprenoid in nature. We have examined the association between isoprenoid metabolism and processing of the lamin A precursor in human and hamster cells. Inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase by mevinolin (lovastatin) specifically depletes endogenous isoprenoid pools and inhibits the conversion of prelamin A to lamin A. Prelamin A processing is also blocked by mevalonate starvation of Mev-1, a CHO cell line auxotrophic for mevalonate. …


Geochemistry Of Selected Maine Peat Deposits, Stephen A. Norton Jan 1990

Geochemistry Of Selected Maine Peat Deposits, Stephen A. Norton

Maine Collection

Geochemistry of Selected Maine Peat Deposits

by Steven Allen Norton

Maine Geological Survey, Department of Conservation, Augusta, Maine, 1990.

Contents: Introduction / Purpose of Study / Location of Study Sites / Methods / Acknowledgements / Results / Water Chemistry / Dating of Short Cores / Chemistry of Short Cores / Core Interpretations / Summary / References Cited


Telomere Structure In Euplotes Crassus: Characterization Of Dna-Protein Interactions And Isolation Of A Telomere-Binding Protein, Carolyn M. Price Jan 1990

Telomere Structure In Euplotes Crassus: Characterization Of Dna-Protein Interactions And Isolation Of A Telomere-Binding Protein, Carolyn M. Price

Department of Chemistry: Faculty Publications

The nucleoprotein structure of telomeres from Euplotes crassus was studied by using nuclease and chemical footprinting. The macronuclear telomeres were found to exist as DNA-protein complexes that are resistant to micrococcal nuclease digestion. Each complex encompassed 85 to 130 base pairs of macronuclear DNA and appeared to consist of two structural domains that are characterized by dissimilar DNA-protein interactions. Dimethyl sulfate footprinting demonstrated that very sequence-specific and salt-stable interactions occur in the most terminal region of each complex. DNase I footprinting indicated that DNA in the region 30 to 120 base-pairs from the 5' end lies on a protein surface; …


A Survey Using 14n:15n Natural Abundance Of The N Fixation By Pasture Legumes In The Field And Of Factors Affecting Fixation, P. Sanford Jan 1990

A Survey Using 14n:15n Natural Abundance Of The N Fixation By Pasture Legumes In The Field And Of Factors Affecting Fixation, P. Sanford

Experimental Summaries - Plant Research

Trial 89AL43, 90AL50, 90KO16

A preliminary survey using 14N:15N natural abundance to assess N2 fixation by pasture legumes in the field.

Location: Albany.

1. Develop a sampling methodology for the 1990 farm survey.
2. An initial assessment of nitrogen fixation by pasture legumes in the field.

Trial 90MT70

Using 14N:15N natural abundance to assess N2-fixation by subterranean clover.

Location Mount Barker Research Station

To examine symbiotic nitrogen fixation by subterranean clover, in detail, through one season in a productive pasture. To better assess the point in the season at which as one time sampling would most accurately determine the proportion …


Biological Markers In Lower Jurassic Synrift Lacustrine Black Shales, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, Jay F. Akes, Paul E. Meriney Jan 1990

Biological Markers In Lower Jurassic Synrift Lacustrine Black Shales, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, Jay F. Akes, Paul E. Meriney

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The East Berlin Formation (Lower Jurassic, Hartford basin, Connecticut, U.S.A.) is distinctive for its six cyclic units of lacustrine black shale and gray mudstone. separated by playa and fluvial redbeds. The black shales arc each about a meter thick and were deposited in subtropical, thermally stratified, oligomictic lakes, the youngest of which (lakes 3 through 6) were large enough to flood most of the basin and attained depths of several tens of meters.

The saturate fractions of solvent extracts of organic-rich black shales from each of the six lakes, collected at fresh roadcuts near East Berlin, arc dominated by extended …


Organic Geochemistry Of A Lower Jurassic Synrift Lacustrine Sequence, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, David F. Bensley, John C. Crelling, R Jay Akes, Paul E. Meriney Jan 1990

Organic Geochemistry Of A Lower Jurassic Synrift Lacustrine Sequence, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, David F. Bensley, John C. Crelling, R Jay Akes, Paul E. Meriney

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Synrift terrestrial strata of the Lower Jurassic East Berlin Formation (Hartford basin, Connecticut, U.S.A.) record cyclical expansion and contraction of major lakes, six of which were deep enough to develop anoxic bottom waters. We have studied one representative lacustrine sequence in detail, sampling a new roadcut near the village of East Berlin. The section examined is 4 m thick, with a gray siltstone at the base, deposited in shallow water, overlain by an organic-rich black shale (deep water), succeeded in turn by another gray siltstone, deposited as the lake waters gradually receded. The upper gray siltstone is chemically distinct from …


4-(Phenylsulfonyl) Butanoic Acid: Preparation, Dianion Generation, And Application To Four Carbon Chain Extension ; Studies Of Organophosphorus Compounds Derived From Serine, Jeffrey A. Frick Jan 1990

4-(Phenylsulfonyl) Butanoic Acid: Preparation, Dianion Generation, And Application To Four Carbon Chain Extension ; Studies Of Organophosphorus Compounds Derived From Serine, Jeffrey A. Frick

Dissertations

No abstract provided.


¹⁷O And ³³S Nuclear Magnetic Resonance Studies Of Some Selected Sulfonates: Concentration And Solvent Dependence, Telitha M. Murray Jan 1990

¹⁷O And ³³S Nuclear Magnetic Resonance Studies Of Some Selected Sulfonates: Concentration And Solvent Dependence, Telitha M. Murray

Dissertations

No abstract provided.


Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin Jan 1990

Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin

Faculty Publications

A water-soluble carbodiimide has been used to end-graft aminated poly (ethylene oxide)(PEO) chemically onto colloidal polystyrene particles. Two particle sizes (115 and 347 nm diameter) and two PEO molecular weights (112 000 and 615 000 g mol–1) were combined to give suspensions with four different ratios of polymer layer thickness to particle radius. Electrophoresis demonstrated that the PEO was grafted, not just adsorbed. Dynamic light scattering showed that the adsorbed and grafted layers had similar structures and that non-ionic surfactant perturbed the PEO configurations. Steady shear and oscillatory rheometry indicated that long-ranged polymeric forces between particles governed the …


Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton Jan 1990

Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton

Chemistry Faculty Publications

Insects have been major pests of humankind at least since the beginning of recorded history. To this day insects continue to cause problems in domestic, agricultural, and health situations. It is no wonder that people have continually sought new solutions to controlling insect pests. Even when new control methods are discovered and established, insects evolve into resistant species so that the method is only of real value for a few brief years. Modern science and technology are now enabling scientists to tear away the fabric that has so long masked physiological and biochemical events critical to insects. Armed with this …


Coatings And Surface Modification By Methane Plasma Polymerization, Chung‐Peng ‐P Ho, H. Yasuda Jan 1990

Coatings And Surface Modification By Methane Plasma Polymerization, Chung‐Peng ‐P Ho, H. Yasuda

Chemistry Faculty Research & Creative Works

Polymers formed from plasma‐polymerized methane were employed to modify the surface properties of silicone rubber membrane. Polymers were evaluated based on the energy input parameter W/FM, where W is the discharge power, F is the monomer flow rate, and M is the molecular weight of the monomer. Dealing with the characteristics of plasma polymerization and the deposited polymer film, the effect of pumping rate on deposition rate and the coating thickness, surface energy, and gas permeabilities of methane‐plasma‐polymer‐coated silicone rubber membrane were investigated in three plasma regions. Because more reactive species are expelled at high pumping rates, the monomer‐deficient region …


Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf Jan 1990

Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf

Chemistry Faculty Research & Creative Works

We Determined the Prevalence of Dementia in 927 Patients with Acute Ischemic Stroke Aged ≥60 Years in the Stroke Data Bank Cohort based on the Examining Neurologist's Best Judgment Diagnostic Agreement among Examiners Was 68% (K=0.34). of 726 Testable Patients, 116 (16%) Were Demented. Prevalence of Dementia Was Related to Age But Not to Sex, Race, Handedness, Educational Level, or Employment Status Before the Stroke. Previous Stroke and Previous Myocardial Infarction Were Related to Prevalence of Dementia Although Hypertension, Diabetes Mellitus, Atrial Fibrillation, and Previous Use of Antithrombotic Drugs Were Not Prevalence of Dementia Was Most Frequent in Patients with …


Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer Jan 1990

Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer

Dissertations, Theses, and Capstone Projects

Nikkomycins and polyoxins are peptidyl nucleoside antibiotics produced by Streptomyces species. They are potent inhibitors of chitin synthetases from pathogenic fungi, and polyoxins have been used in Japan for many years as agricultural fungicides and for insect control. Since chitin synthetase is not found in mammals and both families of antibiotics are not toxic, these inhibitors are potentially attractive for clinical use. Unfortunately these compounds seem to have only a fungistatic action, and they are not used clinically at present.

A procedure for efficiently obtaining nikkomycins X and Z of very high purity from crude antibiotic is described. These nikkomycins …


The Effects Of Crosslinking On The Stability And Autoxidation Rate Of Human Hemoglobin A, Thao Yang Jan 1990

The Effects Of Crosslinking On The Stability And Autoxidation Rate Of Human Hemoglobin A, Thao Yang

Dissertations

No abstract provided.


Ua66/7/2 Hilltopper News, Wku Chemistry Oct 1989

Ua66/7/2 Hilltopper News, Wku Chemistry

WKU Administration Documents

Newsletter created by and about the WKU Chemistry department.


Identification And Quantitation Of Volatile Amines In Marine Sediments, Chuen Mei Huang Oct 1989

Identification And Quantitation Of Volatile Amines In Marine Sediments, Chuen Mei Huang

Chemistry & Biochemistry Theses & Dissertations

Pore waters which were taken from sediments of the Chesapeake Bay were analyzed to determine the presence of volatile amines. A purge-and-trap technique was used to concentrate the amines. Then, following derivatization with heptaflourobutyric anhydride, the HFBA-amines were analyzed by gas chromatography with electron capture detection and with mass spectrometric detection. One secondary amine, diethylamine with a concentration of 0.3-0.6 uM, was found in a total of three pore water samples from cores collected on two different dates. A primary amine, sec-butylamine with a concentration of O. 05 AIM, was also found in one of these same samples. Another primary …


Study Of Acetone Extractable Organic Matter From Airborne Particulate Matter From An Urban Site, Wenhui Wu Sep 1989

Study Of Acetone Extractable Organic Matter From Airborne Particulate Matter From An Urban Site, Wenhui Wu

Theses

Two seasonal periods (Winter 1988; Summer 1988) of daily Newark urban air samples were collected on glass fiber filters. Each filter was first extracted with dichloromethane and subsequently with acetone. Quarterly composites of each were then tested for mutagenicity. The results of the analysis of the less polar dichloromethane extracts were reported in the thesis of Junghen Lwo. A modified fractionation scheme involving acid-base partitioning and silica gel column chromatography has been used as the first step in the bioassay-directed search for significant levels of mutagenic compounds in extracts of inhalable (IP 10) ambient air particulates. The biologically "hot" fractions …


Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak Aug 1989

Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

The theory for measuring ligand binding constants from footprinting autoradiographic data associated with a single binding site is derived. If the ligand and DNA cleavage agent compete for a common site, the spot intensities are not proportional to the amount of DNA not blocked by ligand. The analysis of a single site is experimentally illustrated by using results for the anticancer drug actinomycin D interacting with the duplex d(TAGCGCTA)2 as probed with the hydrolytic enzyme DNase I.


Photocycloaddition Of 4,5',8-Trimethylpsoralen And Oleic Acid Methyl Ester: Product Structures And Reaction Mechanism, Kathleen G. Specht, W. Robert Midden, Miles R. Chedekel Aug 1989

Photocycloaddition Of 4,5',8-Trimethylpsoralen And Oleic Acid Methyl Ester: Product Structures And Reaction Mechanism, Kathleen G. Specht, W. Robert Midden, Miles R. Chedekel

Chemistry Faculty Publications

The stereochemical structures of the four adducts formed between oleic acid methyl ester (OAME) and 4,5',8-trimethylpsoralen (tmPso) have been determined. Assignment of the tmPso 'H NMR spectrum was accomplished by analogy to two coumarin model compounds and with the use of homonuclear decoupling and resonance enhancement. Assignment of the lH NMR spectra for the OAME-tmPso adducts was made by analogy to the spectra of OAME and tmPso and using 2D &resolved and COSY analyses. The configurations of the cyclobutyl rings in these adducts was determined by The stereochemical structures of the four adducts formed between oleic acid methyl ester (OAME) …


Mounting Sex Pheromone: A Novel Pheromone Responsible For Mate Recognition In The Ixodidae, Jgc Hamilton Jul 1989

Mounting Sex Pheromone: A Novel Pheromone Responsible For Mate Recognition In The Ixodidae, Jgc Hamilton

Theses and Dissertations in Biomedical Sciences

Cholesterol oleate was demonstrated to be the cuticular contact sex pheromone of Dermacentor variabilis. This pheromone which has been termed the Mounting Sex Pheromone (MSP) was also demonstrated to be present on the surface of D. andersoni, Amblyomma maculatum and A. americanum. This contact sex pheromone enables males excited and attracted by 2,6-dichlorophenol to identify the female as a potential mating partner. The MSP is the second in the series of three sex pheromones guiding the hierarchy of behavioral responses which constitute tick courtship behavior. Tests with D. variabilis and D. andersoni showed that this pheromone …


Simultaneous Determination Of 3-Methoxy-4-Hydroxyphenyl-Glycol, Homovanillic Acid, And 5-Hydroxyindoleacetic Acid In Plasma By High Performance Liquid Chromatography, Yung-Te Tseng Jul 1989

Simultaneous Determination Of 3-Methoxy-4-Hydroxyphenyl-Glycol, Homovanillic Acid, And 5-Hydroxyindoleacetic Acid In Plasma By High Performance Liquid Chromatography, Yung-Te Tseng

Chemistry & Biochemistry Theses & Dissertations

A rapid, reliable, and sensitive method for simultaneous determination of 3-methoxy-4-hydroxyphenylglycol (MHPG), Homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5- HIAA) in plasma is described. The method is based on high performance liquid chromatography with electrochemical detection. Samples were filtered with Amicon Centrifree micropartition systems and extracted with organic solvent before chromatography. Chromatographic separation of sample components was achieved isocratically in a C18 reverse-phase column. Quantitation was performed by measuring the peak height ratios of the sample components to an internal standard. Analytical recoveries ranged from 50.78 (SD 4.2%) to 67.94 (SD 3.28). Within-run coefficient of variations (CVs) ranged from 3.78 …


Determination Of Benzo(A)Pyrene Metabolites In The Bile Of Winter Flounder From The New York Bight, Xingmin Liu May 1989

Determination Of Benzo(A)Pyrene Metabolites In The Bile Of Winter Flounder From The New York Bight, Xingmin Liu

Theses

A method for detecting the concentration of BaP Metabolites in fish tissues has been developed. The analytical procedure includes extraction of PAH and BaP Metabolites from fish bile, liver extract and muscle extract; reduction of metabolites to BaP using hydriodic acid; and subsequent analysis of the BaP by thin layer chromatography with fluorescence detection. The method is applied to tissues from fish collected from polluted as well as clean reference waters and experimental tanks with dilutions of treated industrial wastewater. Experimental results on one kind of bottom-dwelling fish, winter flounder, which comes from the Hudson-Raritan Estuary, NY, where the water …


Synthesis Of Site Specific 1, N^2-Ethenodeoxyguanosine In A Small Oligonucleotide, Kathryn A. Carolin May 1989

Synthesis Of Site Specific 1, N^2-Ethenodeoxyguanosine In A Small Oligonucleotide, Kathryn A. Carolin

Wayne State University Theses

Malondiadehyde (MDA) is a known carcinogen and mutagen produced by lipid peroxidation and prostaglandin synthesis in vivo. MDA is unique from structurally related compounds, methyl glyoxal and acrolein, because it produces frameshift mutations whereas the latter compounds induce base-pair substitutions. MDA forms several adducts with deoxyguanosine but it is not certain which one causes the frameshift mutations. Ideally, a single adduct on a replicating genome could simulate the in vivo process by which MDA mutagenesis would occur. This technique is known as site-specific mutagenesis. The approach of choice for site-specific mutagenesis experiment is the gapped heteroduplex method which requires the …


Origins Of The Quantum Efficiency Duality In The Primary Photochemical Event Of Bacteriorhodopsin, Robert R. Birge, Leonore A. Findsen, Albert F. Lawrence, Mark Masthay, Chian-Fan Zhang May 1989

Origins Of The Quantum Efficiency Duality In The Primary Photochemical Event Of Bacteriorhodopsin, Robert R. Birge, Leonore A. Findsen, Albert F. Lawrence, Mark Masthay, Chian-Fan Zhang

Chemistry Faculty Publications

Experimental and theoretical evidence is presented which suggests that two distinct forms of light-adapted bacteriorhodopsin may exist. We propose that these two forms have characteristic photocycles with significantly different primary quantum yields. INDO-PSDCI molecular orbital procedures and semiempirical molecular dynamics simulations predict that one ground state geometry of bR undergoes photochemistry with a primary quantum yield, Φ1, of ~ 0.27, and that a second ground state geometry, with a slightly displaced counterion, yields Φ1 ~ 0.74. This theoretical model is supported by the observation that literature measurements of Φ1 tend to fall into one of two categories- those that observe …