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Articles 3691 - 3720 of 3982
Full-Text Articles in Chemistry
Speciation Of Selenium In Serum, Alice Tsapayi-Musapatike
Speciation Of Selenium In Serum, Alice Tsapayi-Musapatike
Chemistry & Biochemistry Theses & Dissertations
We investigated the separation of selenoprotein P and extracellular (serum) glutathione peroxidase using a concanavalin A affinity column. We were able to show that the method does not adequately separate serum glutathione peroxidase from selenoprotein P because human glutathione peroxidase binds strongly to the column. We also found that albumin can interfere with measurement serum of glutathione peroxidase activity when hydrogen peroxide is used as the substrate. When t-butyl hydroperoxide was used as the substrate, less than 10% of the measured activity was due to the presence of albumin. We also found that the pH of the elution buffer plays …
Comparison Of The Dichlorination Of Organic N-Chloramines By Caroate And By Bisulfite: A Kinetic Study, Said H. Lubbad
Comparison Of The Dichlorination Of Organic N-Chloramines By Caroate And By Bisulfite: A Kinetic Study, Said H. Lubbad
Chemistry & Biochemistry Theses & Dissertations
Bisulfite is commonly used to dechlorinate chlorinated municipal wastewater. However, several studies suggest that bisulfite is not effective in dechlorinating N-chlorinated amino components of wastewater. The purpose of this study was to investigate the effectiveness of an alternate dechlorinating agent, caroate (peroxysulfate), and to compare its rate of dechlorination of three different types of chloramines with that of bisulfite.
Four N-chlorinated amino compounds were investigated: N-chlorodiethylamine, N chloroalanylphenylalanine, N-chloroglycylphenylalanine, and N-[2-(N'-chloroimino) propanoyl]phenylalanine. These compounds were selected from different families of N chloramines to study the effect of structure on dechlorination by both caroate and bisulfite. At pH …
Grand Canonical Monte Carlo And Modified Singlet Integral Equations For The Density Profile Of A Yukawa Fluid Near A Planar Wall, Douglas Henderson, Wilmer Olivares-Rivas, Leo Degreve, Jacqueline Quintana
Grand Canonical Monte Carlo And Modified Singlet Integral Equations For The Density Profile Of A Yukawa Fluid Near A Planar Wall, Douglas Henderson, Wilmer Olivares-Rivas, Leo Degreve, Jacqueline Quintana
Faculty Publications
Results for the density profile for Yukawa molecules near a hard wall and an exponential attractive wall are presented for Grand Canonical Monte Carlo (GCMC) simulations, for the singlet hypernetted chain (HNC) integral equation and for a modified version of the Lovett–Mou–Buff–Wertheim (LMBW-1) which uses the exact contact value theorem. The results of the standard singlet HNC are quite poor. If the LMBW equation is modified (but still using the bulk direct correlation function) the results at high temperature become reasonable. However, the results at low temperatures, close to the bulk coexistence curve, are only a partial improvement. The contact …
Celluloid Blackness : Race, Modernity, And The Conflicted Roots Of American Cinema (1915-1939), Lincoln Farr
Celluloid Blackness : Race, Modernity, And The Conflicted Roots Of American Cinema (1915-1939), Lincoln Farr
Honors Theses
Introduction: "The Problem of the Twentieth Century" In a full page interview in the New York Times on May 29, 1912, the Swiss psychiatrist Dr. Carl G. Jung told the American people, "It seems to me that you are about to discover yourselves. You have discovered everything else-all the land of this continent; all the resources, all the hidden things of nature."Jung used the interview to address the American people, at a moment which he somehow recognized as crucial in the development of human civilization. America, the "tragic" country which he struggled to comprehend, would soon become the harbinger of …
Laser-Initiated Decomposition Products Of Indocyanine Green (Icg) And Carbon Black Sensitized Biological Tissues, John M. Kokosa, Andrzej Przyjazny, Kenneth Eugene Bartels, Massoud Motamedi, Donald J. Hayes, David B. Wallace, Christopher J. Frederickson
Laser-Initiated Decomposition Products Of Indocyanine Green (Icg) And Carbon Black Sensitized Biological Tissues, John M. Kokosa, Andrzej Przyjazny, Kenneth Eugene Bartels, Massoud Motamedi, Donald J. Hayes, David B. Wallace, Christopher J. Frederickson
Chemistry & Biochemistry Publications
Organic dyes have found increasing use a s sensitizers in laser surgical procedures, due to their high optical absorbances. Little is known, however, about the nature of the degradation products formed when these dyes are irradiated with a laser. Previous work in our laboratories has shown that irradiation of polymeric and biological tissues with CO2 and Nd:YAG lasers produces a host of volatile and semivolatile by-products, some of which are known to be potential carcinogens. This work focuses on the identification of the chemical by-products formed by diode laser and Nd:YAG laser irradiation of indocyanine green (ICG) and carbon black …
Binding Of Cobalt (Iii) To Nucleic Acids Via Reaction With [Co(Nh3)5(Oh2)]3+, David M. Calderone
Binding Of Cobalt (Iii) To Nucleic Acids Via Reaction With [Co(Nh3)5(Oh2)]3+, David M. Calderone
Seton Hall University Dissertations and Theses (ETDs)
No abstract provided.
Synthesis And Characterization Of Modified Silica Gel As An Intermediate In The Generation Of Gaseous Standard Mixtures, M. Prokopowicz, K. Lewandowska, A. Skwierawska, Andrzej Przyjazny, Jan F. Biernat, J. Namiesnik
Synthesis And Characterization Of Modified Silica Gel As An Intermediate In The Generation Of Gaseous Standard Mixtures, M. Prokopowicz, K. Lewandowska, A. Skwierawska, Andrzej Przyjazny, Jan F. Biernat, J. Namiesnik
Chemistry & Biochemistry Publications
A possibility of extending analytical applications of chemically modified silica gels is described. This involves their utilization for the generation of gaseous standard mixtures consisting of methyl chloride as the analyte and nitrogen as a carrier gas to be used for the calibration of the GC-FID system. N-methylmorpholine was chemically bonded to the propylsilylated surface of silica gel forming chloride of an appropriate immobilized compound which, under certain conditions, undergoes thermal decomposition yielding a single, volatile component (methyl chloride). Such a method of generating specific amounts of a standard substance can be used both for a single point calibration and …
Identification Of The Adp-L-Glycero-D-Manno-Heptose-6-Epimerase (Rfad) And Heptosyltransferase Ii (Rfaf) Biosynthesis Genes From Nontypeable Haemophilus Influenzae 2019, W A. Nichols, B W. Gibson, William Melaugh, N G. Lee, M Sunshine, M A. Apicella
Identification Of The Adp-L-Glycero-D-Manno-Heptose-6-Epimerase (Rfad) And Heptosyltransferase Ii (Rfaf) Biosynthesis Genes From Nontypeable Haemophilus Influenzae 2019, W A. Nichols, B W. Gibson, William Melaugh, N G. Lee, M Sunshine, M A. Apicella
Chemistry Faculty Publications
Haemophilus influenzae is an important human pathogen. The lipooligosaccharide (LOS) of H. influenzae has been implicated as a virulence determinant. To better understand the assembly of LOS in nontypeable H. influenzae (NtHi), we have cloned and characterized the rfaD and rfaF genes of NtHi 2019, which encode the ADP-L-glycero-D-manno-heptose-6-epimerase and heptosyltransferase II enzymes, respectively. This cloning was accomplished by the complementation of Salmonella typhimurium lipopolysaccharide (LPS) biosynthesis gene mutants. These deep rough mutants are novobiocin susceptible until complemented with the appropriate gene. In this manner, we are able to use novobiocin resistance to select for specific NtHi LOS inner core …
Characterization Of A Transposon Tn916-Generated Mutant Of Haemophilus Ducreyi 35000 Defective In Lipooligosaccharide Biosynthesis, B W. Gibson, A A. Campagnari, William Melaugh, M A. Apicella, S Grass, Jing Wang, Katherine L. Palmer, R S. Munson
Characterization Of A Transposon Tn916-Generated Mutant Of Haemophilus Ducreyi 35000 Defective In Lipooligosaccharide Biosynthesis, B W. Gibson, A A. Campagnari, William Melaugh, M A. Apicella, S Grass, Jing Wang, Katherine L. Palmer, R S. Munson
Chemistry Faculty Publications
To define the role of the surface lipooligosaccharide (LOS) of Haemophilus ducreyi in the pathogenesis of chancroid, Tn916 mutants of H. ducreyi 35000 defective in expression of the murine monoclonal antibody (MAb) 3F11 epitope on H. ducreyi LOS were identified by immunologic screening. One mutant, designated 1381, has an LOS which lacks the MAb 3F11 epitope and migrates with an increased mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The gene disrupted by the Tn916 element in strain 1381 was identified by cloning the sequences flanking the Tn916 element. The sequences were then used to probe a lambda DASHII genomic library. …
Complexes Between Nascent Polypeptides And Their Molecular Chaperones In The Cytosol Of Mammalian Cells, Daryl K. Eggers, W. J. Welch, W. J. Hansen
Complexes Between Nascent Polypeptides And Their Molecular Chaperones In The Cytosol Of Mammalian Cells, Daryl K. Eggers, W. J. Welch, W. J. Hansen
Faculty Publications, Chemistry
Folding of newly synthesized proteins in vivo is believed to be facilitated by the cooperative interaction of a defined group of proteins known as molecular chaperones. We investigated the direct interaction of chaperones with nascent polypeptides in the cytosol of mammalian cells by multiple methods. A new approach using a polyclonal antibody to puromycin allowed us to tag and capture a population of truncated nascent polypeptides with no bias as to the identity of the bound chaperones. In addition, antibodies that recognize the cytosolic chaperones hsp70, CCT (TRiC), hsp40, p48 (Hip), and hsp90 were compared on the basis of their …
Sodium Nitrite Alone Protects The Brain O _I_ Microsomal Ca -Atpase Against Potassium Cyanide-Induced Neurotoxicity In Rats, Odutayo O. Odunuge, G.. A. Adenuga
Sodium Nitrite Alone Protects The Brain O _I_ Microsomal Ca -Atpase Against Potassium Cyanide-Induced Neurotoxicity In Rats, Odutayo O. Odunuge, G.. A. Adenuga
Faculty Publications
The effect of a short-term oral administration of potassium cyanide (KCN) (200 ppm in diet) with or without sodium nitrite (NaNO2) pretreatment on rat brain microsomal Ca2* ATPase was investigated. The specific activity value of the enzyme significantly decreased (p<0.05) by 50% compared with control and by 63% for KCN-treated rats compared with KCN-treated rats pretreated with NaNO;,. There was no significant difference at the h = 0.05 level between the values obtained for the control and KCN-treated rats pretreated with NaNO,. These results show both that feeding lowers brain microsomal Ca2f-ATPase activity and that NaNO, has a protective role (antidote function) in that respect.
Molecular Engineering Of Side-Chain Liquid Crystalline Polymers By Living Polymerizations, Coleen Pugh, Alan L. Kiste
Molecular Engineering Of Side-Chain Liquid Crystalline Polymers By Living Polymerizations, Coleen Pugh, Alan L. Kiste
Chemistry and Biochemistry
“Living” anionic, cationic, metalloporphyrin and ring-opening metathesis polymerizations have been used to prepare well-defined side-chain liquid crystalline homopolymers, block and graft copolymers and statistical copolymers. This paper analyzes their successes and failures by reviewing the mechanistic aspects and experimental conditions of each type of polymerization, and identifies other classes of mesogenic monomers that could be polymerized in a controlled manner in the future. The emerging structure/property relationships are then identified using well-defined SCLCPs in which only one structural feature is varied while all others remain constant.
The thermal transitions of liquid crystalline polymethacrylates, polynorbomenes and poly(viny1 ether)s reach their limiting …
Protein-Protein And Protein-Dna Interactions At The Bacteriophage T4 Dna Replication Fork. Characterization Of A Fluorescently Labeled Dna Polymerase Sliding Clamp, Daniel J. Sexton, Theodore E. Carver, Anthony J. Berdis, Stephen J. Benkovic
Protein-Protein And Protein-Dna Interactions At The Bacteriophage T4 Dna Replication Fork. Characterization Of A Fluorescently Labeled Dna Polymerase Sliding Clamp, Daniel J. Sexton, Theodore E. Carver, Anthony J. Berdis, Stephen J. Benkovic
Chemistry Faculty Publications
The T4 DNA polymerase holoenzyme is composed of the polymerase enzyme complexed to the sliding clamp (the 45 protein), which is loaded onto DNA by an ATP-dependent clamp loader (the 44/62 complex). This paper describes a new method to directly investigate the mechanism of holoenzyme assembly using a fluorescently labeled cysteine mutant of the 45 protein. This protein possessed unaltered function yet produced substantial changes in probe fluorescence intensity upon interacting with other components of the holoenzyme. These fluorescence changes provide insight into the role of ATP hydrolysis in holoenzyme assembly. Using either ATP or the non-hydrolyzable ATP analog, adenosine …
The Carboxyl Terminus Of The Bacteriophage T4 Dna Polymerase Is Required For Holoenzyme Complex Formation, Anthony J. Berdis, Patrice Soumillion, Stephen J. Benkovic
The Carboxyl Terminus Of The Bacteriophage T4 Dna Polymerase Is Required For Holoenzyme Complex Formation, Anthony J. Berdis, Patrice Soumillion, Stephen J. Benkovic
Chemistry Faculty Publications
To further elucidate the mechanism and dynamics of bacteriophage T4 holoenzyme formation, a mutant polymerase in which the last six carboxyl-terminal amino acids are deleted, was constructed, overexpressed, and purified to homogeneity. The mutant polymerase, designated ΔC6 exo−, is identical to wild-type exo− polymerase with respect to kcat, kpol, and dissociation constants for nucleotide and DNA substrate. However, unlike wild-type exo− polymerase, the ΔC6 exo− polymerase is unable to interact with the 45 protein to form the stable holoenzyme. A synthetic polypeptide corresponding to the carboxyl terminus of the wild-type exo− polymerase was tested as an in vitro inhibitor of …
Fisheries Research Report No 107 - Chemical Composition Of Yabbies (Cherax Albidus Clark 1936) From Western Australian Farm Dams, Kevin A. Francesconi, Noel M. Morrissy
Fisheries Research Report No 107 - Chemical Composition Of Yabbies (Cherax Albidus Clark 1936) From Western Australian Farm Dams, Kevin A. Francesconi, Noel M. Morrissy
Fisheries Research Reports
Proximate analyses, amino acid and fatty acid profiles, mineral composition and heavy metal and pesticide residues have been determined for tail muscle from Cherax albidus Clark 1936 (the yabby), sampled from Western Australian farm dams. The proximate analysis values for water, protein, ash, carbohydrate and energy content and the amino acid and fatty acid profiles of yabby tail muscle were similar to those reported for other decapods. Fat levels were low and, hence, cholesterol was very low in tail meat. Organochlorine pesticides were undetectable and heavy metal residues were well below maximum permitted concentrations for human consumption.
Open-Path Fourier Transform Infrared Studies Of Large-Scale Laboratory Biomass Fires, Robert J. Yokelson, David W. T. Griffith, Darold E. Ward
Open-Path Fourier Transform Infrared Studies Of Large-Scale Laboratory Biomass Fires, Robert J. Yokelson, David W. T. Griffith, Darold E. Ward
Chemistry and Biochemistry Faculty Publications
A series of nine large-scale, open fires was conducted in the Intermountain Fire Sciences Laboratory (IFSL) controlled-environment combustion facility. The fuels were pure pine needles or sagebrush or mixed fuels simulating forest-floor, ground fires; crown fires; broadcast burns; and slash pile burns. Mid-infrared spectra of the smoke were recorded throughout each fire by open path Fourier transform infrared (FTIR) spectroscopy at 0.12 cm−1 resolution over a 3 m cross-stack pathlength and analyzed to provide pseudocontinuous, simultaneous concentrations of up to 16 compounds. Simultaneous measurements were made of fuel mass loss, stack gas temperature, and total mass flow up the …
High-Power Broadly Tunable Picosecond Ir Laser System For Use In Nonlinear Spectroscopic Applications, D. E. Gragson, B. M. Mccarty, G. L. Richmond, D. S. Alavi
High-Power Broadly Tunable Picosecond Ir Laser System For Use In Nonlinear Spectroscopic Applications, D. E. Gragson, B. M. Mccarty, G. L. Richmond, D. S. Alavi
Chemistry and Biochemistry
We developed a high-power tunable picosecond IR laser system suitable for nonlinear spectroscopic investigations. We employ a Ti:sapphire regenerative amplifier that produces 1.9-ps, 17-cm−1, 800-nm pulses at 1 kHz as a pump source. White-light generation in ethylene glycol and optical parametric amplification in potassium titanyl phosphate are used to produce the IR pulses. The tuning range extends from 2.4 to 3.8 μm in the idler and 1.0 to 1.2 μm in the signal. A total efficiency (signal plus idler) as high as 20% was achieved. The spatial, spectral, and temporal characteristics of the IR beam are presented along …
Comparison Of Positive Screening And Confimatory Results From Federally Mandated Drug Testing Of Urine, Mary M. Stuck
Comparison Of Positive Screening And Confimatory Results From Federally Mandated Drug Testing Of Urine, Mary M. Stuck
Community & Environmental Health Theses & Dissertations
The purpose of this study was to analyze the accuracy of FDA approved immunoassays for the detection of drug positive urine samples.
Federal civilian employees are tested under the strict protocol of the Department of Health and Human Services mandatory guidelines for federal workplace drug testing programs. The guidelines provide for a two instrument testing protocol for the analysis of urine samples. The first is an FDA approved immunoassay. Samples which test positive on this screening immunoassay are then submitted for confirmatory testing with the "gold standard" gas chromatography/mass spectrometry.
Agency monthly drug testing summaries, required under the DHHS guidelines …
Isolation From Soil Microorganisms That Are Inhibitory To Wheat Seeding Pathogens, Kynita Wilson-Humphrey
Isolation From Soil Microorganisms That Are Inhibitory To Wheat Seeding Pathogens, Kynita Wilson-Humphrey
McCabe Thesis Collection
Many diseases caused by bacteria, viruses, or fungi are responsible for the ruin of a great number of crops annually. At present, many of these crops are being treated for diseases by synthetic or man-made chemicals. Some of the chemicals have been proved to have adverse effects on the environment, including humans and animals. Very few non-chemical means are available to farmers at this time to control these pathogens. This is due to the fact that many of the means of control have little effect against the pathogens or diseases. This research attempts to isolate microorganisms from the soil which …
Reconnecting The Sciences, John Eggebrecht, Raymond Dagenais, Don Dosch, Norman J. Merczak, Margaret N. Park, Susan C. Styer, David Workman
Reconnecting The Sciences, John Eggebrecht, Raymond Dagenais, Don Dosch, Norman J. Merczak, Margaret N. Park, Susan C. Styer, David Workman
Faculty Publications & Research
During the last three years at the Illinois Mathematics and Science Academy, we have been working on a partial reconstruction of Whitehead's "one subject matter," a course reconnecting biology, chemistry, earth and space sciences, and physics into an Integrated Science program.
Critical Pressures In Multicomponent Lipid Monolayers, John P. Hagen, Harden M. Mcconnell
Critical Pressures In Multicomponent Lipid Monolayers, John P. Hagen, Harden M. Mcconnell
Chemistry and Biochemistry
Epifluorescence microscopy has been used previously to study coexisting liquid phases in lipid monolayers of dihydrocholesterol and dimyristoylphosphatidylcholine at the air/water interface. This binary mixture has a critical point at room temperature (22°C), a monolayer pressure of approx. 10 mN/m, and a composition in the vicinity of 20-30 mol% dihydrocholesterol. It is reported here that this critical pressure can be lowered, raised, or maintained constant by systematically replacing molecules of this phosphatidylcholine with molecules of a phosphatidylethanolamine, or an unsaturated phosphatidylcholine, or mixtures of the two, while maintaining the dihydrocholesterol concentration at 20 mol%. Thus, even complex mixtures of lipids …
The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson
The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson
Chemistry Faculty Publications
The major lipooligosaccharides of the sexually transmitted pathogen Haemophilus ducreyi 35000 have been previously found to terminate in N-acetyllactosamine and sialyl-N-acetyllactosamine, Neu5Ac alpha 2-->3Gal beta 1-->4GlcNAc (W. Melaugh, N. J. Phillips, A. A. Campagnari, M. V. Tullius, and B. W. Gibson, Biochemistry 33: 13070-13078, 1994). In this study, mass spectrometry and composition analyses have shown that the lipooligosaccharides from three other H. ducreyi strains also contain N-acetyllactosamine and are highly sialylated (approximately 30 to 50%), although one African strain was found to contain neither of these structural features.
Space-Based Genetic Cryoconservation Of Endangered Species, Michael Noah Mautner
Space-Based Genetic Cryoconservation Of Endangered Species, Michael Noah Mautner
Chemistry Publications
Genetic materials of endangered species must be maintained, for cryoconservation, permanently near liquid nitrogen temperatures below 77 K. Due to the instability of human institutions, permanent safety is best provided at storage sites that maintain passively the needed low temperatures, and provide barriers to access. The required conditions are available in permanently shaded polar lunar craters with equilibrium temperatures of 8 to 40 K, on the moons of Saturn, and unshielded storage satellites. A genetic depository can be incorporated readily into planned lunar programmes.
An Improved Synthesis Of 2-(Hydroxymethyl)Indene, Hasan Palandoken, William T. Mcmillen, Michael H. Nantz
An Improved Synthesis Of 2-(Hydroxymethyl)Indene, Hasan Palandoken, William T. Mcmillen, Michael H. Nantz
Chemistry and Biochemistry
No abstract provided.
An Nmr Investigation Of The Effect Of Hydrogen Bonding On The Rates Of Rotation About The C-N Bonds In Urea And Thiourea, Karl A. Haushalter, Janice Lau, John D. Roberts
An Nmr Investigation Of The Effect Of Hydrogen Bonding On The Rates Of Rotation About The C-N Bonds In Urea And Thiourea, Karl A. Haushalter, Janice Lau, John D. Roberts
All HMC Faculty Publications and Research
The interaction between urea and tetrabutylammonium acetate was investigated in dimethylformamide/ dimethyl sulfoxide solutions using ¹H and 15^N NMR. The chemical-shift behavior of the urea protons is consistent with a urea-acetate hydrogen-bonded complex involving both carboxylate oxygens and the urea hydrogens trans to the carbonyl oxygen with K_assoc = 120 ± 10. Line shape analysis of the temperature-dependent ¹H NMR spectra show that ∆G^‡ for rotation about the C-N bond of urea changes only slightly from 11.0 ± 0.1 to 11.2 ± 0.1 kcal/mol on 1:1 molar addition of tetrabutylammonium acetate to a dilute solution of urea. A parallel investigation …
A New High Pressure Sapphire Nuclear Magnetic Resonance Cell, Shi Bai, Craig M. Taylor, Charles L. Mayne, Ronald J. Pugmire, David M. Grant
A New High Pressure Sapphire Nuclear Magnetic Resonance Cell, Shi Bai, Craig M. Taylor, Charles L. Mayne, Ronald J. Pugmire, David M. Grant
Faculty Publications
A new version of a single-crystal sapphire high pressure nuclear magnetic resonance (NMR) cell is described that is capable of controlling the sample pressure independent of the temperature. A movable piston inside the cell adjusts and controls the sample pressure from ambient conditions to 200 atm within plus or minus 0.3 atm. The linewidth at half-height for a 13C spectrum of carbon dioxide at 15degrees C and 57.8 atm is found to be 0.5 Hz. The carbon dioxide gas/liquid phase transition is clearly observed by measuring 13C chemical shifts as the sample pressure approaches equilibrium. The time required for this …
Mile-A-Minute Weed, (Polygonum Perfoliatum L.), An Invasive Vine In Natural And Disturbed Sites, J. Douglas Oliver
Mile-A-Minute Weed, (Polygonum Perfoliatum L.), An Invasive Vine In Natural And Disturbed Sites, J. Douglas Oliver
Faculty Publications and Presentations
Polygonum perfoliatum L. (Polygonaceae) or mile-a-minute weed, from eastern Asia, has been spreading through wild and disturbed areas of the mid-Atlantic United States. It has a wide ecological amplitude and is found on stream banks, moist thickets, roadsides, nurseries, wood-piles, clearings, and ditches. Polygonum perfoliatum presents serious problems for reforestation because it thrives where forests are clear-cut. A southward direction of spread indicates that the species will probably proliferate in at least some southern states. Mechanical control is not likely to be completely effective because seeds are often left behind. No appropriate biocontrols are known. The plant poses a threat …
Acidic Marine Biotoxins Implicated In Diarrhetic Shellfish Poisoning, Eoin P. Carmody
Acidic Marine Biotoxins Implicated In Diarrhetic Shellfish Poisoning, Eoin P. Carmody
Theses
An okadaic acid (OA) etiology has been demonstrated for most outbreaks of diarrhetic shellfish poisoning (DSP) in Europe, An isomer of OA, dinophysistoxin-2 (DTX-2), has recently been found in Irish waters and, in 1991 and 1994, was the major toxin during prolonged infestations in cultivated mussels (Mytilus edulis) along the south-west coast of Ireland.
The OA class of DSP toxins have been analysed by HPLC using modified versions of three established fluorescent derivatisation methods. A ‘dual tag’ method for the confirmation of specific toxins has also been developed.
Survey work has been carried out over the past four years on …
Mechanistic Studies On Malate Dehydrogenase From Escherichia Coli, S. Kirk Wright
Mechanistic Studies On Malate Dehydrogenase From Escherichia Coli, S. Kirk Wright
Masters Theses
Kinetic studies and chemical modification studies were performed on malate dehydrogenase from Escherichia coli (eMDH). Chemical modification studies using diethylpyrocarbonate and iodoacetic acid, along with log V/K profiles indicate that one ionizing group with a pKa between 7.9 and 8.5 acts as a general acid/base in the catalytic mechanism. Log V profiles suggest that malate binds to the correctly protonated form of the enzyme. These results imply that a histidine residue is required for catalysis.
A primary deuterium kinetic isotope effect of 1.43 (±0.14) was observed on V/K using malate-2-d, while no isotope effect was measured on Vmax …
Effects Of Ammonium Perchlorate On The Thyroid Hormone Levels Of The Sprague-Dawley Rat, James H. King Jr.
Effects Of Ammonium Perchlorate On The Thyroid Hormone Levels Of The Sprague-Dawley Rat, James H. King Jr.
Theses and Dissertations
The purpose of this research was to determine the threshold dose for ammonium perchlorate (AP) in the Sprague-Dawley rat. No dose response data exist for AP and the EPA has studied literature on the subject of perchlorates to determine a provisional reference dose. The Perchiorate Group, a consortium of DoD and industry representatives, believes this provisional reference dose is too conservative. This experiment was executed to provide dose response data on which to base a more accurate reference dose. The study consisted of eight groups of 12 Sprague-Dawley rats, six male and six female, which were exposed to incremental doses …