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Brigham Young University

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Articles 301 - 330 of 348

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

A New High Pressure Sapphire Nuclear Magnetic Resonance Cell, Shi Bai, Craig M. Taylor, Charles L. Mayne, Ronald J. Pugmire, David M. Grant Jan 1996

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 …

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New Optical Cell Design For Laser Flash Photolysis Studies In Supercritical Fluids, Steven R. Goates, Milton L. Lee, Qin Ji, Edward M. Eyring, Rudi Van Eldik, Kedika Bal Reddy Jan 1995

New Optical Cell Design For Laser Flash Photolysis Studies In Supercritical Fluids, Steven R. Goates, Milton L. Lee, Qin Ji, Edward M. Eyring, Rudi Van Eldik, Kedika Bal Reddy

Faculty Publications

A high-pressure optical cell has been designed that achieves an effective separation between the chemical sample and the pressurizing medium and system. This design limits possible sample contamination and catalytic effects under supercritical fluid sample conditions. Laser flash photolysis experiments were carried out on molybdenum hexacarbonyl dissolved in supercritical CO2. The thermal ring closure reaction of the species Mo(CO)5L, where L is 2,2- bipyridine was found to proceed at rates comparable to those measured previously in liquid benzene or toluene. Much larger activation volumes were found for the reaction in supercritical CO2 than in liquid toluene.

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Semiclassical Quantization Of A Nonintegrable System: Pushing The Fourier Method Into The Chaotic Regime, Karl Sohlberg, Randall B. Shirts Nov 1994

Semiclassical Quantization Of A Nonintegrable System: Pushing The Fourier Method Into The Chaotic Regime, Karl Sohlberg, Randall B. Shirts

Faculty Publications

Semiclassical Einstein–Brillouin–Keller (EBK) quantization of the nonintegrable Hénon–Heiles Hamiltonian succeeds using the Fourier transform method of Martens and Ezra. Two innovations are required for this success: (1) the use of tunneling corrected quantizing actions obtained from an approximate, one-dimensional Hamiltonian and (2) exploitation of intermediate-time approximate quasiperiodicity or "vague tori'' wherein the Fourier transform of chaotic motion over 10–100 vibrational periods allows the determination of frequencies and amplitudes which approximate motion during the time interval. Approximate tori, actions, and EBK energy levels are then straightforward. We use an interpolation method to smooth over small resonance zones that are not expected …

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The Structure And Dynamics Of The Cs2 Molecular Ion, Karl Sohlberg, Chan Yibai Sep 1994

The Structure And Dynamics Of The Cs2 Molecular Ion, Karl Sohlberg, Chan Yibai

Faculty Publications

Several common elementary methods of computing molecular properties, prerequisite to molecular dynamics studies, are tested for their validity for CS+2. Judged sufficiently accurate, these methods are then used to aid in investigating the collisionally activated dissociation of CS+2 upon impact with xenon. Rice–Ramsperger–Kassel–Marcus (RRKM) unimolecular decay rate calculations are presented and compared to experimental studies employing collisional activation. RRKM theory is shown to reproduce the experimental results for collision energies near threshold. When corrected for vibrational anharmonicity, the RRKM calculation shows agreement with the experimental results over a slightly wider range of energies. A discussion is given on the applicability …

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High-Temperature Battery Calorimeter, L. D. Hansen, R. H. Hart, D. M. Chen, H. F. Gibbard Apr 1982

High-Temperature Battery Calorimeter, L. D. Hansen, R. H. Hart, D. M. Chen, H. F. Gibbard

Faculty Publications

A battery calorimeter was built for the measurement of thermal energy generation of high-temperature lithium–aluminum/iron sulfide battery cells, which are under development for electric vehicle propulsion and other energy storage applications. The calorimeter was designed with a temperature range of 400˚–500˚C, a detection limit of 1 mW, and an upper limit of heat flow of 50 W. The results of measurements on 200-Ah LiAl/FeS cells were in excellent agreement with the predictions of thermodynamic calculations based on precise measurements of the total cell polarization and the temperature coefficient of the emf. Details of the construction and operation principles of this …

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Heating-Effect Minimization In Dye Lasers, Kenneth Lee Matheson, James M. Thorne Aug 1979

Heating-Effect Minimization In Dye Lasers, Kenneth Lee Matheson, James M. Thorne

Faculty Publications

Optical pumping of dye lasers deposits heat nonuniformly in the active medium. Because the refractive index of a liquid or gas is a function of temperature, gradients are created which refract the laser beam. This effect is sometimes serious enough to quench laser action. In this paper, we evaluate the effects caused by optical pumping with a coaxial flashlamp and suggest ultraviolet absorbers and wavelength shifters as materials for minimizing the problem

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An Emulsion Dye Laser, Kenneth Lee Matheson, James M. Thorne Nov 1978

An Emulsion Dye Laser, Kenneth Lee Matheson, James M. Thorne

Faculty Publications

A laser dye which is insoluble in water has been dissolved in hexane and emulsified in a water matrix. When pumped with a nitrogen laser, this mixture was observed to lase. The emulsion is superior to a simple hexane solution because the excellent thermo-optical properties of the water matrix help prevent refractive-index gradients from degrading laser performance. This is a useful characteristic for flash-pumped dye lasers, laser-pumped dye lasers, and liquid filters. Another type of solvent system, a critical solution, is also discussed. For certain dyes, a critical solution has even better thermo-optical properties because of its ability to absorb …

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The Relationship Of Reduced Levels Of Atp To Inhibited Chondrogenesis In The Production Of Limb Deformity Induced By 6-Aminonicotinamide, Val C. Sheffield May 1977

The Relationship Of Reduced Levels Of Atp To Inhibited Chondrogenesis In The Production Of Limb Deformity Induced By 6-Aminonicotinamide, Val C. Sheffield

Theses and Dissertations

6-aminonicotinamide (6-AN), an analogue and antagonist of nicotinamide, impairs cartilage formation and results in shortening of the limb when administered to chick embryos. 6-AN forms an abnormal NAD analogue (6-ANAD), which inhibits the activity of NAD-dependent enzymes associated with the production of ATP. The mechanism of action of 6-AN was studied by measuring the biosynthesis of protein and DNA, and the sulfation and glycosylation of chondroitin sulfate in control and 6-AN treated cartilage from 8-day chick embryos. The cartilage was also assayed for ATP levels. Incorporation of Na235SO4 was inhibited by 6 h treatment with 10 μg/ml 6-AN, whereas 3H-thymidine …

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Isolation, Purification, Scanning Electron Microscopy And Bacterial Dna Uptake Of Plant Protoplasts, Bronwyn G. Hughes Apr 1977

Isolation, Purification, Scanning Electron Microscopy And Bacterial Dna Uptake Of Plant Protoplasts, Bronwyn G. Hughes

Theses and Dissertations

Protoplasts were isolated from tobacco and barley leaves in sucrose or mannitol using commercially available cellulases and macerozymes. Barley growth and protoplast isolation and purification conditions were optimized so that protoplasts were obtained in high yields free of unwanted debris and organelles. A technique for processing barley and tobacco protoplasts for examination by scanning electron microscopy was developed in which protoplasts seem to have maintained their structural integrity. Barley and tobacco protoplasts took up 3H-B. subtilis DNA, 125I-B. subtilis DNA or 125I-M. luteus DNA as a linear function of time (0-6 hr) and DNA concentration (0-200 μg/ml). Up to 16 …

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Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack Feb 1977

Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Angle dependent intermolecular potential energy surfaces for the two states (2A’ and 2A”) that arise from the interaction of ground (X^2II) state NO with Ar are calculated using the electron gas model to obtain the short range interactions. The average and difference of the two interaction energies are fit to analytic forms convenient for use in scattering calculations and joined smoothly onto the long range van der Waals potential previously determined. The results, which appear to be of useful accuracy, and the applicability of the electron gas model to such open shell–closed shell interactions are discussed.

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Effect Of Altitude On The Peripheral Degradation Of Thyroxine In The Uinta Ground Squirrel (Citellus Armatus), Stuart K. Ware Dec 1976

Effect Of Altitude On The Peripheral Degradation Of Thyroxine In The Uinta Ground Squirrel (Citellus Armatus), Stuart K. Ware

Theses and Dissertations

Various methods were employed to detect changes in the peripheral degradation of thyroxine (T4) in adult Uinta ground squirrels (Citellus armatus) collected at two different altitudes (5400 and 9000 feet.) Plasma half-life of injected T4-125I (tl/2) was significantly decreased with altitude, as was T4-125I distribution space (TDS) and T4 degradation and secretion rate (TSR). In vitro deiodination of T4-125I by heart homogenates was not affected, while urinary excretion of thyroxine derived iodide was increased at high altitude 44-70 hours post-injection. Both total and free serum T4 concentrations were reduced at high altitude, although not significantly. The cause of the reduced …

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Esr Study Of Free Radicals In Irradiated Single Crystals Of Potassium Hydroxylamine Disulfonate, B. J. Wilson, Robert W. Holmberg Aug 1976

Esr Study Of Free Radicals In Irradiated Single Crystals Of Potassium Hydroxylamine Disulfonate, B. J. Wilson, Robert W. Holmberg

Faculty Publications

Two free radicals formed when single crystals of potassium hydroxylamine disulfonate are irradiated with gamma rays at 77degrees K were studied by ESR. The ESR spectra result from a predominant center (radical A) exhibiting large 14N and 1H hyperfine splittings and from lesser amounts of Fremy's radical [O-dotN(SO3)2-2]. The g and hyperfine tensors of these radicals have been evaluated and are discussed. Radical A, whose identity remains in doubt, may be regarded as the precursor to Fremy's radical; on warming its lines decay and those of Fremy's radical are formed. Lines from radical A decrease in strength and those of …

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Van Der Waals Interactions Of Carbon Monoxide, Gregory A. Parker, Russell T. Pack Mar 1976

Van Der Waals Interactions Of Carbon Monoxide, Gregory A. Parker, Russell T. Pack

Faculty Publications

Pade approximant methods and experimental frequency dependent polarizabilities are used to calculate reliable van der Waals C6 coefficients for the interaction of CO with He, Ne, Ar, Kr, Xe, H, Li, Na, K, Rb, Cs, H2, N2, O2, CO2, and CO. Error bounds are given for the C6 coefficients and for the CO oscillator strength sums.

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Van Der Waals Interactions Of Ii-State Linear Molecules With Atoms. C6 For No(X 2Π) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack Mar 1976

Van Der Waals Interactions Of Ii-State Linear Molecules With Atoms. C6 For No(X 2Π) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Formulas are derived for the van der Waals Cn coefficients for the interaction of a diatomic molecule in a II electronic state with an S-state atom. Two triatomic states arise from the degenerate IIstate. The average of the two energies has the usual Legendre polynomial (PL) angular dependence, but the difference in energies of the two states is shown to have associated Legendre polynomial (PML with M=2) angular dependence. Procedures for including spin orbit coupling are included, and the extension to interactions of Delta- and Phi-state molecules is discussed. Values of the spherical part of the C6 coefficients for the …

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Comment On ''Inelastic Scattering In Atom-Diatomic Molecule Collisions. I. Rotational Transitions In The Sudden Approximation'', Russell T. Pack Feb 1976

Comment On ''Inelastic Scattering In Atom-Diatomic Molecule Collisions. I. Rotational Transitions In The Sudden Approximation'', Russell T. Pack

Faculty Publications

It is argued that conflicting approximations in a recent paper [J. R. Stallcop, J. Chem. Phys. 61, 5085 (1974)] render the resulting theory invalid.

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Studies Of N⁵, N¹⁰-Methylene Tetrahydrofolate Reductase From Porcine Kidney And Mouse L1210-Induced Tumor Tissues, Purification And Interaction With Antifolates, David W. Jayme Dec 1975

Studies Of N⁵, N¹⁰-Methylene Tetrahydrofolate Reductase From Porcine Kidney And Mouse L1210-Induced Tumor Tissues, Purification And Interaction With Antifolates, David W. Jayme

Theses and Dissertations

Methylene tetrahydrofolate reductase has been purified 1000-fold from porcine kidney and 400-fold from mouse L1210-induced tumor tissue by classical methods. The enzyme preparations have been demonstrated to be essentially free of contaminating methionine synthetase and serine transhydroxymethylase activity. Studies of the kinetic properties of the kidney and tumor enzymes, with respect to the reverse reaction using N5-methyl tetrahydrofolate as the variable substrate, have indicated Km values of 2.0 and 2.4 x 10-4 M, respectively. Inhibition of this key branch point enzyme in folate metabolism by a number of antimetabolites indicates that several of these antifolate compounds exhibit enzyme inhibition superior …

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The Effect Of Altitude On Thyroid Function Of The Uinta Ground Squirrel (Citellus Armatus), Wendell Lee Wells Aug 1975

The Effect Of Altitude On Thyroid Function Of The Uinta Ground Squirrel (Citellus Armatus), Wendell Lee Wells

Theses and Dissertations

Thyroid uptake and distribution of 125I, concentrations of T4 and T3 in serum and thyroids and concentrations of TSH in serum and pituitaries were measured to determine thyroid function of Uinta Ground Squirrels (Citellus armatus) native to 5,400 and 9,000 feet elevations to evaluate alterations in the state of the thyroid due to increased altitude. Uptake of 125I was 60 percent lower by squirrels from 9,000 feet. Incorporation of 125I into T3 was greater at the higher elevation, but absolute thyroid T3 concentrations were similar at both elevations. No significant differences were found in serum T3 concentrations, but squirrels living …

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Close Coupling Test Of Classical And Semiclassical Cross Sections For Rotationally Inelastic Ar-N2 Collisions, Russell T. Pack Apr 1975

Close Coupling Test Of Classical And Semiclassical Cross Sections For Rotationally Inelastic Ar-N2 Collisions, Russell T. Pack

Faculty Publications

Accurate quantum mechanical close coupling (CC) integral cross sections are reported for rotationally inelastic Ar-N2 collisions at room temperature using an empirical intermolecular potential. These cross sections are used to test the infinite order sudden (IOS) approximation and the results of several methods [classical trajectories (CT), full sudden (SA), generalized phase shift (GPS), and classical limit generalized phase shift (CGPS)] as reported in the preceding paper by Pattengill. The IOS approximation works very well for cross sections involving low rotational states. The CT method works well for all the cross sections examined, justifying the popular belief that the rotational motion …

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Erratum: On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack Nov 1974

Erratum: On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack

Faculty Publications

In Eqs. (28) and (29) p should be changed to t.

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Absorption Of Caffeine Through Isolated Rat Small Intestine, William James Hatch Aug 1974

Absorption Of Caffeine Through Isolated Rat Small Intestine, William James Hatch

Theses and Dissertations

Intestines of fifty-six albino rats of the Holtzman strain were removed and perfused with Krebs bicarbonate buffered solutions containing caffeine. After one hour of absorbtion, caffeine was extracted from the serosal fluids in chloroform and concentrations were determined spectrophotometrically. It was found that all portions of the small intestine transported caffeine against a concentration gradient. This transport mechanism demonstrated saturation kinetics and was inhibited by ouabain. It was concluded that the movement of caffeine from the mucosa to the serosa of the small intestine cannot be the result of simple diffusion. Possible mechanisms by which the absorption of caffeine takes …

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Rotationally Inelastic Molecular Scattering. Computational Tests Of Some Simple Solutions Of The Strong Coupling Problem, Thomas P. Tsien, Gregory A. Parker, Russell T. Pack Nov 1973

Rotationally Inelastic Molecular Scattering. Computational Tests Of Some Simple Solutions Of The Strong Coupling Problem, Thomas P. Tsien, Gregory A. Parker, Russell T. Pack

Faculty Publications

Partial cross sections (opacity functions) for rotational transitions in atom-diatom collisions are computed in the infinite-order sudden (IOS) approximation and compared with accurate close-coupling (CC) calculations. Agreement is good in the dominant coupling (small total angular momentum J) region. Simple methods for calculating integral inelastic cross sections are discussed, and it is found that accurate cross sections can often be computed very simply, even when large numbers of channels are coupled together, by using IOS or first-order sudden (FOS) approximations for small J and CC or exponential Born (EBDW) methods for large J.

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I. An Isothermal Titration Microcalorimeter. Ii. Importance Of Micronutrients In Nutrition. Iii. Zinc Bibliography, John Willard Gardner Aug 1973

I. An Isothermal Titration Microcalorimeter. Ii. Importance Of Micronutrients In Nutrition. Iii. Zinc Bibliography, John Willard Gardner

Theses and Dissertations

I. An isothermal titration microcalorimeter having a colume of 4 ml and capable of temerature control to ±2 x 10-5°C is described. Major components include a constant temperature water bath controlled to ±3 x 10-4°C, a platinum reation vessel, and an isothermal control circuit consisting of constant Peltier thermoelectric cooling and variable Joule heating controlled by a thermistor in an AC Wheatstone bridge circuit. The calorimeter was tested by measuring the heat of ionization of water and was found to produce data accurate to ± 0.1% where small samples are used such as in the investigation of many biological systems.

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The Effects Of Deficiencies Of Certain Mineral Nutrients On The Activity And Various Properties Of Ribulose-1,5-Diphosphate Carboxylase From Barley (Hordeum Vulgare L.), Philip Alan Harrison Aug 1973

The Effects Of Deficiencies Of Certain Mineral Nutrients On The Activity And Various Properties Of Ribulose-1,5-Diphosphate Carboxylase From Barley (Hordeum Vulgare L.), Philip Alan Harrison

Theses and Dissertations

Barley plants grown in Mg, Mn, Zn and Cu deficient media were analyzed for specific activity, total activity and amount of RuDPCase present. Percent dry weight, as well as chlorophyll and soluble protein content were determined. All deficiencies caused lower chlorophyll and RuDPCase concentrations than occurred in the control. Soluble protein content, however, was higher in all deficient plants than in the control, either on a dry or a fresh weight basis. The addition of 18 μM Mn^2+ increased the activity of Mg^2+ containing RuDPCase preparations as much as 133% above normal. The specific activity of RuDPCase from Mg, Mn, …

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The Effects Of Thiamin Deficiency And Thiamin Antagonists On Cardiac Function In The Rat, D. James B. Sutherland Apr 1973

The Effects Of Thiamin Deficiency And Thiamin Antagonists On Cardiac Function In The Rat, D. James B. Sutherland

Theses and Dissertations

A study was made to determine what biochemical changes were involved in the slowing of the rat heart rate during thiamin deprivation, pyrithiamin or oxythiamin treatment. The appearance of bradycardia during progressive thiamin deficiency was shown to be related to the reduction in myocardial enzymatic activity of pyruvate (PDH) and 2-ketoglutarate (2-KGDH) dehydrogenase, and not due to inanition alone since pair-fed control rats did not show bradycardia until the agonal stage. Bradycardia was not the result of reduced energy since CP, ATP, ADP, and AMP levels remained normal even though PDH and 2-KGDH activity dropped to 20% of normal by …

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Transforming Ability Of Bacillus Subtilis Dna Taken Up By Barley Embryos, Christine Tolman Ence Apr 1973

Transforming Ability Of Bacillus Subtilis Dna Taken Up By Barley Embryos, Christine Tolman Ence

Theses and Dissertations

Purified Bacillus subtilis DNA taken up by one-day-old barley embryos and permanently fixed within the barley cell is shown to have maintained its biological activity in B. subtilis transformation. Cesuim chloride density gradient centrifugation of DNA isolated from the roots of barley embryos after the uptake and incorporation of radioactive, bromouracil-labelled B. subtilis DNA indicates the presence of the bacterial DNA in several discreet bands of well-defined density, whose density is changed by sonication. These preliminary findings concerning the fate of bacterial DNA taken up by barley roots are discussed in terms of the recombination model of Ledoux and Huart …

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On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack Dec 1972

On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack

Faculty Publications

An improvement to the WKB quantum condition for the rotation-vibration levels of diatomic molecules, known empirically to give RKR potentials of increased accuracy and to account for the Dunham correction Y00, is derived using uniform asymptotic methods. The role of the Langer transformation in this problem is also discussed.

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Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell Aug 1972

Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell

Theses and Dissertations

The lipids of the spores of the Basidiomycetes: Ustilago bullata, Lycoperdon perlatum and Calvatia gigantea were investigated. The spores of U. bullata were found to have hydrocarbons ranging from C_9 to C_24, methyl esters of fatty acids ranging from C_14 to C_24, and free fatty acids from C_14 to C_24. The spores of L. perlatum were found to have few hydrocarbons (C_22 being the predominent one); no methyl esters were detected and the fatty acids were from C_15 to C_18. Long chain aldehydes (C_30) were also detected in low concentration. At the ultrastructural level the Lycoperdon spores were found to …

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Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Bronwyn Geraldine Hughes Jul 1972

Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Bronwyn Geraldine Hughes

Theses and Dissertations

A possible method for the synthesis of ordered oligoribonucleotides involves primer-dependent polynucleotide phosphorylase (PNPase) synthesis using the RNase A or T1 resistant N-cyclohexyl-N'-β(4-methylmorpholinium)ethylcarbodiimide chloride (CMC-Cl) derivatives of uridine or guanosine containing primers. Thus, CMC-UpA, CMC-GpA, CMC-UpCpC, CMC-GpApC, and ApApApApU-CMC were prepared and studied as primers for PNPase in 15 min 14C-ADP polymerization reactions and also in 6-10 hr synthesis reactions. The CMC-primers were not suitable primers for PNPase catalyzed synthesis reactions for either time. The PNPases used in such studies were contaminated with nuclease that showed the following order of susceptibility: UpA > CpC, GpA > ApU, ApA. Even a highly purified …

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On The Mechanism Of Low-Temperature Termolecular Atomic Recombination, Russell T. Pack, Richard L. Snow, Wesley D. Smith Jan 1972

On The Mechanism Of Low-Temperature Termolecular Atomic Recombination, Russell T. Pack, Richard L. Snow, Wesley D. Smith

Faculty Publications

A simple theory of gas-phase termolecular atomic recombination kinetics is presented which treats the bound-complex (BC) mechanism in a fashion which parallels the Roberts, Bernstein, and Curtiss resonance theory of the energy-transfer (ET) mechanism. The ET rate constant has a low temperature maximum, but the BC rate constant does not. The contributions of the two mechanisms to the low-temperature recombination of hydrogen atoms, with He, Ar, and H2 as third bodies, are estimated and compared. The presence (absence) of a low-temperature maximum in the observable total rate constant is determined by absence (presence) of bound vibrational levels of the hydrogen-third …

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Autoradiographic Studies Of The Distribution Of Serotonin In The Rat Brain, Brent D. Wagstaff Aug 1971

Autoradiographic Studies Of The Distribution Of Serotonin In The Rat Brain, Brent D. Wagstaff

Theses and Dissertations

Serotonin (5-hydroxytryptamine, 5-HT), considered to be a synaptic transmitter within the central nervous system, has been shown to be localized mainly in the paleocortex of the brain. Others have shown disturbances of normal 5-HT metabolism to be associated with mental illness and disease. Attempts to inject tritium labelled 5-HT into cerebrospinal fluid of the rat brain for anatomical localization studies were·made. The following observations were noted, (1) there exists a perivascular space in which fluid flows and distribution is relatively uninhibited as compared to subarachnoid space, (2) the labelled 5-HT penetration of brain tissue parenchyma is restricted and radioactivity is …

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