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Articles 30901 - 30930 of 34557

Full-Text Articles in Physical Sciences and Mathematics

Catecholamine Secretion In Bovine Chromaffin Cells : Influence Of Immune-Derived Factors, Zhaohui Wang Jan 1993

Catecholamine Secretion In Bovine Chromaffin Cells : Influence Of Immune-Derived Factors, Zhaohui Wang

Master's Theses

No abstract provided.

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Homogeneous Nucleation In Supersaturated Vapors Of Polar Molecules: Acetonitrile, Benzonitrile, Nitromethane, And Nitrobenzene, D. Wright, R. Caldwell, C. Moxely, M. S. El-Shall Jan 1993

Homogeneous Nucleation In Supersaturated Vapors Of Polar Molecules: Acetonitrile, Benzonitrile, Nitromethane, And Nitrobenzene, D. Wright, R. Caldwell, C. Moxely, M. S. El-Shall

Chemistry Publications

The critical supersaturations (S c ) required for the homogeneous nucleation of acetonitrile, benzonitrile, nitromethane, and nitrobenzene vapors have been measured over wide temperature ranges using a thermal diffusion cloud chamber. At T r =0.44, the experimental results are higher than the predictions of the classical nucleation theory by 20% (CH3NO2), 50% (CH3CN), 57% (C6H5NO2), and 112% (C6H5CN). This trend correlates well with the dipole moments and to a lesser extent with the polarizabilities of these substances. Corresponding states of simple fluids and …

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Analysis Of Homogeneous Nucleation Data Of Polar Molecules: Vapor Association, Dipole Orientation, And Elongated Clusters, D. Wright, M. S. El-Shall Jan 1993

Analysis Of Homogeneous Nucleation Data Of Polar Molecules: Vapor Association, Dipole Orientation, And Elongated Clusters, D. Wright, M. S. El-Shall

Chemistry Publications

In this paper we present the results of several theoretical models examined in order to explain the observed systematic deviations of the homogeneous nucleation of highly polar substances from the predictions of the classical nucleation theory (CNT). It is found that molecular association in acetronitrile or nitromethane vapor cannot explain the observed higher supersaturations. Similarly, the use of virial coefficient data to obtain a size dependent surface energy correction factor does not reproduce the experimental results. It is shown that orientation of the surface dipoles within the spherical droplets results in higher supersaturations in agreement with the experimental findings. We …

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Processes For Producing Doxorubicin, Daunomycinone, And Derivatives Of Doxorubicin, Desmond M. S. Wheeler Jan 1993

Processes For Producing Doxorubicin, Daunomycinone, And Derivatives Of Doxorubicin, Desmond M. S. Wheeler

Chemistry Department: Faculty Publications

To produce doxorubicin and its analogues methyl 3alpha, 5alpha-dihydroxy-5beta-(trimethylsilylethynyl)- 2alpha-nitromethylcyclohexane-1beta-carboxylate acetonide is condensed with 1,4-dihydro-4,4,5-trimethoxy-1-oxonaphthalene in the presence of 1,8-diazabicyclo-5.4.0]undec-7-ene in an aprotic solvent to produce 3-(2beta-carbomethoxy-4-beta-ethynyl-4-alpha, 6alpha-(di-O-isopropylidenyl)cyclohexanyl-1-yl)-nitromethyl-4,4,5-trimethoxy-1-oxo-1,2,3,4-tetrahydronaphthalene; which is cyclized to produce 9beta ethynyl-12-hydroxy-7alpha, 9alpha-(di-O-iso propylidenyl)-6-nitro-4,5,5-trimethoxy-5,5a,6- 6a,7,8,9,10,10a,11-decahydro -11-naphthacenone. The decahydro-11-naphthacenone is converted to 7alpha 9alpha,(di-O-isopropyl-idenyl)-4,5-dimethoxy-9beta ethynyl-12-hydroxy-6-nitro-6,6a,7,8,9,10,10a, 11 octahydro-11, -naphthacenone. The octahydro-11 naphthacenone is oxidized to 7alpha-9alpha, (di-O-iso propyl-idenyl)-9beta-ethynyl-11-hydroxy-4-methoxy-6- nitro-7,8,9,10-tetrahydro-5,12-naphthacenedione which is converted to 6-desoxy-6-nitrodaunomycinone, daunomycinone and related 6-substituted analogues of daunomycinone.

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Soluble Highly Reactive Form Of Calcium And Reagents Thereof, Reuben D. Rieke Jan 1993

Soluble Highly Reactive Form Of Calcium And Reagents Thereof, Reuben D. Rieke

Chemistry Department: Faculty Publications

A soluble highly reactive form of calcium, prepared from Ca(II) salts and a reducing agent in ethereal, polyethereal, or hydrocarbon solvents, is presented. This form of calcium can be used in the preparation of organocalcium reagents. The organocalcium reagents resulting from the reaction of the soluble highly reactive calcium with organic compounds containing either halide, cyanide, a 1,3-diene, or a polyunsaturated functionality, are stable, useful reagents for organic synthesis. The organocalcium halide reagents undergo Grignard-type reactions. They also undergo reactions with Cu(I) salts to form organocalcium cuprate reagents. The organocalcium cuprate reagents undergo a variety of cross-coupling reactions. The soluble …

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Preparation And Use Of (2-Butene-1,4-Diyl)Magnesium Complexes In Organic Synthess, Reuben D. Rieke Jan 1993

Preparation And Use Of (2-Butene-1,4-Diyl)Magnesium Complexes In Organic Synthess, Reuben D. Rieke

Chemistry Department: Faculty Publications

The magnesium complexes of cyclic hydrocarbons, such as 1,2-dimethylenecycloalkanes, are readily prepared in high yields using highly reactive magnesium. Reactions of these (2-butene-1,4-diyl)magnesium reagents with electrophiles such as dibromoalkanes, alkyl ditosylates, or bromoalkylnitriles serve as a convenient method for synthesizing spirocyclic systems. Significantly, spirocarbocycles prepared by this method contain functional groups such as the exocyclic double bond or a keto group in one of the rings which could be used for further elaboration of these molecules. Furthermore, fused bicyclic systems containing a substituted five-membered ring can be conveniently prepared at high temperatures by the reactions of (2-butene-1,4- diyl)magnesium complexes with …

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Synthesis, Characterization, And Crystal Structure Of The (Η5-C5ph5)Cr(Co)3 Radical, Ray J. Hoobler, Marc A. Hutton, Mills M. Dillard, Michael Castellani, Arnold L. Rheingold, Anne L. Rieger, Philip H. Rieger, Thomas C. Richards, William E. Geiger Jan 1993

Synthesis, Characterization, And Crystal Structure Of The (Η5-C5ph5)Cr(Co)3 Radical, Ray J. Hoobler, Marc A. Hutton, Mills M. Dillard, Michael Castellani, Arnold L. Rheingold, Anne L. Rieger, Philip H. Rieger, Thomas C. Richards, William E. Geiger

Chemistry Faculty Research

The reaction between Cr(CO)6 and Na(C5Ph5 ) in refluxing diglyme yields [Na(diglyme)3/2][(C5Ph5)Cr(CO)3], 1. Metathesis of 1 with [Ph3P=N=PPh3 ]Cl in CH2Cl2 yields [Ph3P=N=PPh3][(C5Ph5)Cr(CO)3], 2. Oxidation of 1 by AgBF4 in cold THF under an argon atmosphere produces (C5Ph5)Cr(CO)3, 3. Complexes 2 and 3 form a redox pair connected by a quasireversible one-electron process, E0 = -0.69 V vs ferrocene in CH2Cl2, …

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Preparation Of Functionalized Polymers Utilizing A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke Jan 1993

Preparation Of Functionalized Polymers Utilizing A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke

Chemistry Department: Faculty Publications

Calcium-substituted polymeric reagents are provided. These reagents can be prepared via the oxidative addition of a soluble highly reactive calcium species to organic and inorganic polymers containing alkyl, aryl, or alkylaryl pendent groups substituted with halide atoms, cyanide molecules, 1,3-dienes, or any conjugated poly unsaturated system. Preferably, the polymer is a cross linked p-bromopolystyrene, p-chloropolystyrene, p-fluoropolystyrene, or chloromethylated polystyrene. Preferably, the soluble highly reactive calcium species is prepared from the reduction of Ca(II) salts with an alkali metal arene, such as lithium biphenylide. These calcium-substituted polymeric reagents react with a variety of electrophiles to yield functionalized polymers. Reaction with Cu(I) …

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Investigation Of The Structural Heterogeneity Of Lipooligosaccharides From Pathogenic Haemophilus And Neisseria Species And Of R-Type Lipopolysaccharides From Salmonella Typhimurium By Electrospray Mass Spectrometry, B W. Gibson, William Melaugh, Nancy J. Phillips, M A. Apicella, A A. Campagnari, J M. Griffiss Jan 1993

Investigation Of The Structural Heterogeneity Of Lipooligosaccharides From Pathogenic Haemophilus And Neisseria Species And Of R-Type Lipopolysaccharides From Salmonella Typhimurium By Electrospray Mass Spectrometry, B W. Gibson, William Melaugh, Nancy J. Phillips, M A. Apicella, A A. Campagnari, J M. Griffiss

Chemistry Faculty Publications

Heterogeneity in the lipooligosaccharides (LOS) of pathogenic Haemophilus and Neisseria species is evident from the multiplicity of components observed with electrophoretic analyses. Knowledge of the precise structures that make up these diverse LOS molecules is clearly the key to reaching an understanding of pathogenic processes such as phase variation and molecular mimicry. Except for a few cases, little is known about the specific structural features of LOS that underlie phase variation and molecular mimicry, partly because of the inherent difficulties in the structural elucidation of these complex glycolipids. In the lipopolysaccharides (LPS) from Salmonella typhimurium and Escherichia coli, rough, or …

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Polynuclear Mixed-Valence Complexes, David A. Rockcliffe Jan 1993

Polynuclear Mixed-Valence Complexes, David A. Rockcliffe

Dissertations

No abstract provided.

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Solid-State Deuterium Nmr Spectroscopy Of D5-Phenol In White Portland Cement: A New Method For Assessing Solidification/Stabilization, Michael A. Janusa Jan 1993

Solid-State Deuterium Nmr Spectroscopy Of D5-Phenol In White Portland Cement: A New Method For Assessing Solidification/Stabilization, Michael A. Janusa

Faculty Publications

We have developed a new NMR-based procedure for studying waste/cement interactions. This is the first use of deuterium NMR spectroscopy to study waste solidification/ stabilization (S/S). The main feature of deuterium NMR spectroscopy is the ability to monitor molecular reorientations over a wide range of reorientation rates. This technique allows one to determine if a particular deuterated organic waste is effectively solidified/ stabilized and to determine the lower limit of the bond strength between the waste and the cement matrix. Comparison of the predicted and experimental deuterium NMR spectra show that phenol is mainly dissolved in pore waters and, thus, …

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Tables Of Coincidence Orientations For Ordered Tetragonal L Lo Alloys For A Range Of Axial Ratios, Abha Singh, Alexander H. King Jan 1993

Tables Of Coincidence Orientations For Ordered Tetragonal L Lo Alloys For A Range Of Axial Ratios, Abha Singh, Alexander H. King

Alexander H. King

In this paper we develop and apply techniques for computation of CSL, DSCL and step-vector data for grain boundaries in tetragonal materials for a range of axial ratios. This has application to L10 alloys including TiA1, which is a candidate for lightweight high-temperature structural applications. Our results are compared with others and found to be more accurate and complete. We provide data for a wider range of axial ratios than those considered by previous workers. We have also derived equivalent quaternions for tetragonal crystals in tetragonal-crystal coordinates and listed conditions for selecting a unique reduced rotation in tetragonal-crystal coordinates so …

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A Geometrical Rationalization Of The Special Properties Of The 14° [001] Grain Boundary In Yba2cu3o7−Δ, Alexander H. King, Abha Singh Jan 1993

A Geometrical Rationalization Of The Special Properties Of The 14° [001] Grain Boundary In Yba2cu3o7−Δ, Alexander H. King, Abha Singh

Alexander H. King

14° [001] tilt grain boundaries in YBa2Cu3O7−δ have been found to exhibit anomalously good superconducting critical currents, associated with magnetic flux pinning, although no special interfacial structure has heretofore been associated with this misorientation. We present an analysis of the geometry of the grain boundary in question and show that it can correspond to a special interface, within the definition of constrained lattice coincidence, which may lead to new understanding of the superconducting behavior of grain boundaries. Our analysis shows that the tetragonal‐to‐orthorhombic phase transformation may have important effects upon grain boundary structure and properties, indicating new approaches to producing …

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A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver Jan 1993

A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver

Faculty Publications and Presentations

Giant salvinia (Salviniaceae) is a potentially serious aquatic weed that is native to Brazil. It has been reported in more than 20 countries, but is not established in the U.S. at this time. Mitchell and Tur (1975) reported that three years after the formation of the Kariba Reservoir in Africa, giant salvinia blanketed 21.5% or 1003 km2 of the reservoir surface area. Creagh (199111992) wrote, "A single small plant may grow to form a thick mat covering more than 100 sq. km. in just three months - choking lakes and waterways, reducing populations of aquatic plants and animals and in …

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Effect Of Solvent On 1,3-Dipolar Cycloaddition Transition States, Sheila Louise Celsor Jan 1993

Effect Of Solvent On 1,3-Dipolar Cycloaddition Transition States, Sheila Louise Celsor

Dissertations

No abstract provided.

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Provo Pollution Prevention Program, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Theresa Hosick Jan 1993

Provo Pollution Prevention Program, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Theresa Hosick

Fuel Efficiency Automobile Test Publications

No abstract provided.

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Fullerene Derivatives And Fullerene Superconductors, H. H. Wang, J. A. Schlueter, A. C. Cooper, J. L. Smart, M. E. Whitten, U. Geiser, K. D. Carlson, J. M. Williams, U. Welp, J. D. Dudek, M. A. Caleca Jan 1993

Fullerene Derivatives And Fullerene Superconductors, H. H. Wang, J. A. Schlueter, A. C. Cooper, J. L. Smart, M. E. Whitten, U. Geiser, K. D. Carlson, J. M. Williams, U. Welp, J. D. Dudek, M. A. Caleca

Faculty Publications - Department of Biological & Molecular Science

A series of 1:1 Cgo cycloaddition adducts, CgoA (A = anthracene, butadiene, cyclopentadiene, and methylcyclopentadiene), has been synthesized. The products are cleanly separated and characterized by use of TGA, iH-NMR, IR, and mass spectrometry. Among these adducts, Cgodaethylcyclopentadiene) showed the highest thermal stability and was doped with three equivalents of rubidium. The resulting Rb3C6o(MeCp) is a semiconductor but can be thermally converted to the superconducting Rb3C6O through a retro-Diels-Alder reaction. A one-step doping process to prepare Rb3Ceo crystals has been developed. The optimal doping condition occurs at ~300°C. High superconducting shielding fractions: between 60 and 90% and sharp transition widths …

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Synthesis, Superconductivity And Esr Characterization Of Rb3c60 Crystals, J. A. Schlueter, U. Welp, H. H. Wang, U. Geiser, J. M. Williams, M. J. Bauer, J. M. Cho, James L. Smart, S. A. Taha Jan 1993

Synthesis, Superconductivity And Esr Characterization Of Rb3c60 Crystals, J. A. Schlueter, U. Welp, H. H. Wang, U. Geiser, J. M. Williams, M. J. Bauer, J. M. Cho, James L. Smart, S. A. Taha

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

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Preparation Of Functionalized Polymers Utilizng A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke Jan 1993

Preparation Of Functionalized Polymers Utilizng A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke

Chemistry Department: Faculty Publications

Calcium-substituted polymeric reagents are provided. These reagents can be prepared via the oxidative addition of a soluble highly reactive calcium species to organic and inorganic polymers containing alkyl, aryl, or alkylaryl pendent groups substituted with halide atoms, cyanide molecules, 1,3-dienes, or any conjugated poly unsaturated system. Preferably, the polymer is a cross linked p-bromopolystyrene, p-chloropolystyrene, p fluoropolystyrene, or chloromethylated polystyrene. Preferably, the soluble highly reactive calcium species is prepared from the reduction of Ca(II) salts with an alkali metal arene, such as lithium biphenylide. These calcium-substituted polymeric reagents react with a variety of electrophiles to yield functionalized polymers. Reaction with …

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Infarct Topography And Hemiparesis Profiles With Cerebral Convexity Infarction: The Stroke Data Bank, J. P. Mohr, M. A. Foulkes, A. T. Polis, D. (Daniel) B. Hier, C. S. Kase, T. R. Price, T. K. Tatemichi, P. A. Wolf Jan 1993

Infarct Topography And Hemiparesis Profiles With Cerebral Convexity Infarction: The Stroke Data Bank, J. P. Mohr, M. A. Foulkes, A. T. Polis, D. (Daniel) B. Hier, C. S. Kase, T. R. Price, T. K. Tatemichi, P. A. Wolf

Chemistry Faculty Research & Creative Works

For the 183 of 1276 Patients in the NINDS Stroke Data Bank with Convexity Infarction in the Middle Cerebral Artery Territory, the Size of the Infarct Did Not Differ between the Two Sides But the Location of the Main Site of the Infarct Differed: on the Left Side, It Was Centered in the Inferior Parietal Region, and Was Mid-Frontal on the Right. There Was a Good Correlation between Infarct Size and Weakness Severity Whether Estimated by overall Motor Function on One Side, Arm, or Hand Alone. There Was a Poor Correlation, However, for Lesion Location (Lower Third, Middle Third or …

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Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna Jan 1993

Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna

Chemistry Faculty Research & Creative Works

Seven activated esters of indole-3-acetic acid (IAA) [4-oxo-l,2,3-benzotriazin-3-yl indole-3-acetate (IAA-3HBO), succinimido indole-3-acetate (IAA-NHS), 5-norbornene-1,3-dicarboximido indole-3-acetate (IAA-NHND), phthalimido indole-3-acetate (IAA-NHP), naphthalimido indole-3-acetate (IAA-NHN), 4-nitrophenyl indole-3-acetate (IAA-4NP), 8-quinolyl indole-3-acetate (IAA-8HQ)] were prepared and characterized. Their kinetics of aminolysis with butylamine, piperidine, and pyrrolidine in acetonitrile were investigated. In general, the observed pseudo-first-order rate constants, kobs, fit the two-term rate equation kobs = k1[amine] + k2[amine]2. For the aminolysis of six of the esters with piperidine there was no measurable k2 term. The 8-hydroxyquinoline ester and N-hydroxy-naphthalimide ester of indole-3-acetic acid had no measurable k2 term for aminolysis with either pyrrolidine or piperidine. …

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Tetrabutylammonium Benzoate‐Initiated Polymerization Of Propylene Oxide, Xuemin Chen, Michael R. Van De Mark Jan 1993

Tetrabutylammonium Benzoate‐Initiated Polymerization Of Propylene Oxide, Xuemin Chen, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

The polymerization of propylene oxide by the benzoate anion was aided through the use of the tetrabutylammonium counterion. The effect of the tetrabutylammonium ion was to increase the solubility of the salt and to increase the ion separation. The polymerization was carried out in a pressure reactor at temperatures from 40 to 108°C, producing polymer yields of 2–78%. The study addressed the general effects of solvent, temperature, and ratio of initiator to monomer. © 1993 John Wiley & Sons, Inc. Copyright © 1993 John Wiley & Sons, Inc.

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A-Helical Polypeptide Monolayers, Erwin P. Enriquez Jan 1993

A-Helical Polypeptide Monolayers, Erwin P. Enriquez

Chemistry Faculty Publications

In efforts to utilize the a-helical structural motif as a basic building block in the formation of supramolecular assemblies, a study of the self-assembly of a-helical poly(glutamate)s from dilute solution onto a solid support was initiated. In particular, poly(y-benzyl-L-glutamate) [PBLG], which has an unusually robust a-helical conformation, was functionalized at the amino terminus with a disulfide-containing moiety (lipoic acid), which in turn has a specific and strong chemisorptive interaction with gold surfaces. The same end group functionalization was used with the /i-alkyl side chain analogs of PBLG. The resulting self-assembled monolayers were characterized by grazing angle reflection infrared (GIR-IR) spectroscopy, …

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S-H Stretching Frequencies In Ruthenium Mercaptan Complexes And The Crystal And Molecular Structures Of [Cpru(Pph3)2(S-C4h, Haengsoon Park, David Minick, Mark Draganjac, Joey W. Crump, A. W. Cordes, Elizabeth M. Holt Jan 1993

S-H Stretching Frequencies In Ruthenium Mercaptan Complexes And The Crystal And Molecular Structures Of [Cpru(Pph3)2(S-C4h, Haengsoon Park, David Minick, Mark Draganjac, Joey W. Crump, A. W. Cordes, Elizabeth M. Holt

Journal of the Arkansas Academy of Science

No abstract provided.

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A Comparative 2-Dimensional Gel Protein Database Of The Intact And Regenerating Newt Limbs, Panagiotis A. Tsonis Jan 1993

A Comparative 2-Dimensional Gel Protein Database Of The Intact And Regenerating Newt Limbs, Panagiotis A. Tsonis

Biology Faculty Publications

In this paper we describe a two-dimensional gel database of the regenerating newt limb. Protein synthesis was compared in the intact limb, in the 1-week regenerating limb, representing the dedifferentiation stage, and in the 2-week regenerating limb, representing the formation of the blastema. This comparative database provided data on differential expression of about 800 proteins during the process of limb regeneration. In addition, a map has been generated for these proteins for future guidance in characterizing further new, unknown proteins. The overall expression patterns of the proteins indicated that the dedifferentiation stage was marked by down-regulation of most proteins, while …

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Rapamycin-Induced Inhibition Of P34(Cdc2) Kinase Activation Is Associated With G1/S-Phase Growth Arrest In T Lymphocytes, W. G. Morice, Gregory J. Brunn, Gregory Wiederrecht, John Siekierka, R. T. Abraham Jan 1993

Rapamycin-Induced Inhibition Of P34(Cdc2) Kinase Activation Is Associated With G1/S-Phase Growth Arrest In T Lymphocytes, W. G. Morice, Gregory J. Brunn, Gregory Wiederrecht, John Siekierka, R. T. Abraham

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

The macrolide rapamycin (RAP) is a potent inhibitor of interleukin-2 (IL- 2)-induced T-cell proliferation. Current models suggest that RAP, when complexed to its intracellular receptor, FK506-binding protein, interferes with an IL-2 receptor-coupled signaling pathway required for cell-cycle progression from G1- to S-phase. Here we show that RAP treatment inhibits the growth of an IL-2-dependent cytotoxic T-cell line, CTLL-2, in late G1- phase, just prior to entry of the cells into S-phase. In contrast, RAP- treated CTLL-2 cells retained the ability to respond to IL-2 with enhanced cytolytic activity, indicating that RAP was not a general suppressant of cellular responsiveness to …

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Enantiomeric Separation Of Chiral Components Reported To Be In Coffee, Tea, Or Cocoa, Apryll M. Stalcup, K. Helen Ekborg, Mary P. Gasper, Daniel W. Armstrong Jan 1993

Enantiomeric Separation Of Chiral Components Reported To Be In Coffee, Tea, Or Cocoa, Apryll M. Stalcup, K. Helen Ekborg, Mary P. Gasper, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

Literally hundreds of volatile compounds have been identified in coffee, tea, and cocoa. A significant proportion of these compounds are known to be chiral. The enantiomeric composition of most of these compounds is unknown, and until recently there were no efficient analytical procedures for their identification. The advent of cyclodextrin-based chiral stationary phases for capillary gas chromatography provides effective means for the enantioselectivity analysis of many of these compounds. Some of these are known to be flavor and fragrance components that occur naturally or are produced from the manufacturing process (e.g., fermentation, drying, and roasting). © 1993, American Chemical Society. …

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Aspects Of Gold Recovery From An Indigenous Ore, Cormac Patrick Mcnamee Jan 1993

Aspects Of Gold Recovery From An Indigenous Ore, Cormac Patrick Mcnamee

Masters

This project involved the investigation into the basic electrochemistry of the thiourea-formamidine disulphide redox couple and an estimation of the formal potential, Eo1 for the couple. By carrying out optimisation experiments on the leaching of gold from an ore sample from the Avoca mine in Co. Wicklow, the optimum leaching conditions were determined for maximum gold extraction. The effects of various organic and inorganic species on the adsorption of gold onto activated carbon and modified peat were investigated with the use of factorial designed experiments. The Langmuir Isotherm model was applied to estimate the capacity of the carbon for these …

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Nuclear Magnetic Resonance Study Of Antigen-Antibody Complexes, Including Sequence Specific Assignments And Structural Analysis Of Neurophysin As An Antigen Model, Elisar Jamil Barbar Jan 1993

Nuclear Magnetic Resonance Study Of Antigen-Antibody Complexes, Including Sequence Specific Assignments And Structural Analysis Of Neurophysin As An Antigen Model, Elisar Jamil Barbar

Dissertations and Theses

The interaction between molecules is essential in a wide range of biological processes. A detailed knowledge of these interactions is necessary for understanding these processes. Among the systems that involve important interactions is the immune system. NMR spectroscopy has a large number of spectral parameters that were used in this work to study antibody-antigen interactions. These same parameters were also used to begin a structural analysis of a medium-sized protein, neurophysin, that has important interactions with neurohormones, and served here as a model antigen. A set of ligands differing in size and charge was designed and used to probe the …

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Determination Of Hammett Pyridine 3-Aza And 4-Aza Replacement Constants By 1h Nmr Studies Of Amide Systems, Frank L. Setliff, Nikhil G. Soman, Alan D. Toland Jan 1993

Determination Of Hammett Pyridine 3-Aza And 4-Aza Replacement Constants By 1h Nmr Studies Of Amide Systems, Frank L. Setliff, Nikhil G. Soman, Alan D. Toland

Journal of the Arkansas Academy of Science

Values for Hammett pyridine 3-aza and 4-aza replacement constants were obtained by correlation of the amide proton chemical shifts (in DMSO) of some N-(3-pyridyl)-and N-(4-pyridyl)-dichloronicotinamides, benzamides and acetamides with those of their N-(substituted phenyl) amide analogs using standard Hammett a values

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