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Articles 151 - 180 of 197
Full-Text Articles in Physical Sciences and Mathematics
Evidence Of Linear Lattice Expansion And Covalency Enhancement In Rutile Tio2 Nanocrystals, Guangshe Li, Juliana Boerio-Goates, Brian F. Woodfield, Liping Li
Evidence Of Linear Lattice Expansion And Covalency Enhancement In Rutile Tio2 Nanocrystals, Guangshe Li, Juliana Boerio-Goates, Brian F. Woodfield, Liping Li
Faculty Publications
Lattice variations and bonding characteristics in rutile TiO2 nanocrystals were examined by x-ray diffraction and x-ray photoelectron spectroscopy. With a reduction in the physical dimensions, rutile TiO2 nanocrystals show a linear lattice expansion and an anomalous covalency enhancement in apparent contradiction to the ionicity increase in BaTiO3 and CuO nanocrystals as reported recently by S. Tsunekawa et al. [Phys. Rev. Lett. 2000, 85, 3440] and V. R. Palkar et al. [Phys. Rev. B 1996, 53, 2167]. A surface defect dipole model is proposed to explain these physical phenomena in terms of the strong interactions among the surface dipoles that produce …
A Physiochemically Constrained Seawater Culturing System For Production Of Benthic Foraminifera, Christopher J. Hintz, G. Thomas Chandler, Jay M. Bernhardt, Daniel C. Mccorkle, Suzanne M. Havach, Jessica K. Blanks, Timothy J. Shaw
A Physiochemically Constrained Seawater Culturing System For Production Of Benthic Foraminifera, Christopher J. Hintz, G. Thomas Chandler, Jay M. Bernhardt, Daniel C. Mccorkle, Suzanne M. Havach, Jessica K. Blanks, Timothy J. Shaw
Faculty Publications
No abstract provided.
Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber
Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber
Faculty Publications
n- and p-type Ge nanowires were synthesized by a multistep process in which axial elongation, via vapor–liquid–solid (VLS) growth, and doping were accomplished in separate chemical vapor deposition steps. Intrinsic, single-crystal, Ge nanowires prepared by Au nanocluster-mediated VLS growth were surface-doped in situ using diborane or phosphine, and then radial growth of an epitaxial Ge shell was used to cap the dopant layer. Field-effect transistors prepared from these Ge nanowires exhibited on currents and transconductances up to 850 µA/µm and 4.9 µA/V, respectively, with device yields of >85%.
Identification Of An Il-17-Producing Nk1.1neg Inkt Cell Population Involved In Airway Neutrophilia, Paul B. Savage, Marie-Laure Michel, Alexandre Castro Keller, Christophe Paget, Masakazu Fujio, Francois Trottein, Chi-Huey Wong, Elke Schneider, Michael Dy, Maria C. Leite-De-Moraes
Identification Of An Il-17-Producing Nk1.1neg Inkt Cell Population Involved In Airway Neutrophilia, Paul B. Savage, Marie-Laure Michel, Alexandre Castro Keller, Christophe Paget, Masakazu Fujio, Francois Trottein, Chi-Huey Wong, Elke Schneider, Michael Dy, Maria C. Leite-De-Moraes
Faculty Publications
Invariant natural killer T (iNKT) cells are an important source of both T helper type 1 (Th1) and Th2 cytokines, through which they can exert beneficial, as well as deleterious, effects in a variety of inflammatory diseases. This functional heterogeneity raises the question of how far phenotypically distinct subpopulations are responsible for such contrasting activities. In this study, we identify a particular set of iNKT cells that lack the NK1.1 marker (NK1.1neg) and secrete high amounts of interleukin (IL)-17 and low levels of interferon (IFN)-{gamma} and IL-4. NK1.1neg iNKT cells produce IL-17 upon synthetic ({alpha}-galactosylceramide [{alpha}-GalCer] or PBS-57), as well …
Diel Activity Patterns Of The Louisiana Pine Snakes (Pituophis Ruthveni) In Eastern Texas, Marc J. Ealy, Robert R. Fleet, D. Craig Rudolph
Diel Activity Patterns Of The Louisiana Pine Snakes (Pituophis Ruthveni) In Eastern Texas, Marc J. Ealy, Robert R. Fleet, D. Craig Rudolph
Faculty Publications
This study examined the diel activity patterns of six Louisiana pine snakes in eastern Texas using radio-telemetry. snakes were monitored for 44 days on two study areas from May to October 1996. Louisana pine snakes were primarily diurnal with moderate crepuscular activity, spending the night within pocket gopher burrows or inactive on the surface. During daylight hours, snakes spent approximately 59% of their time underground within gopher burrows, burned out/rotten stumps, or nine-branded armadillo (Dasypus novemcinctus) burrows. Remaining time was spent on the surface either close to subteranean refuge, or in long distance movements that generally terminet at …
Self-Aligned Mechanical Attachment Of Carbon Nanotubes To Silicon Dioxide Structures By Selective Silicon Dioxide Chemical-Vapor Deposition, Jed D. Whittaker, Ghaleb A. Husseini, Matthew A. Linford, Robert C. Davis, Markus Brink
Self-Aligned Mechanical Attachment Of Carbon Nanotubes To Silicon Dioxide Structures By Selective Silicon Dioxide Chemical-Vapor Deposition, Jed D. Whittaker, Ghaleb A. Husseini, Matthew A. Linford, Robert C. Davis, Markus Brink
Faculty Publications
A self-aligned thin-film deposition technique was developed to mechanically attach carbon nanotubes to surfaces for the fabrication of structurally robust nanotube-based nanomechanical devices. Single-walled carbon nanotubes were grown by thermal chemical-vapor deposition (CVD) across 150-nm-wide SiO2 trenches. The nanotubes were mechanically attached to the trench tops by selective silicon tetraacetate-based SiO2 CVD. No film was deposited on the nanotubes where they were suspended across the trenches.
Runoff And Sediment Losses From Annual And Unusual Storm Events From The Alto Experimental Watersheds, Texas: 23 Years After Silvicultural Treatments, Matthew W. Mcbroom, R Scott Beasley, Mingteh Chang, Brian Gowin, George G. Ice
Runoff And Sediment Losses From Annual And Unusual Storm Events From The Alto Experimental Watersheds, Texas: 23 Years After Silvicultural Treatments, Matthew W. Mcbroom, R Scott Beasley, Mingteh Chang, Brian Gowin, George G. Ice
Faculty Publications
Evaluating the potential impacts of intensive silvicultural practices on water quality is critical for establishing the long-term sustainability of contemporary forest management practices. From 1979 to 1985, a study involving nine small (~2.5 ha) forested watersheds was conducted near Alto, Texas in the upper western Gulf-Coastal Plain to evaluate the impacts then-current silvicultural practices on water quality. In the years following the study, silvicultural Best Management Practices (BMPs) including Streamside Management Zones (SMZs) and other erosion control practices evolved and questions arose about the applicability of earlier results to current practices. In 1999, these same watersheds were reinstrumented to evaluate …
Bacteriological Water Quality Of Forested And Pastured Streams Receiving Land-Applied Poultry Litter, Matthew W. Mcbroom, Chang Mingteh, Charles Wells
Bacteriological Water Quality Of Forested And Pastured Streams Receiving Land-Applied Poultry Litter, Matthew W. Mcbroom, Chang Mingteh, Charles Wells
Faculty Publications
Poultry production is a growing industry in East Texas, generating about 360,000 m tons of broiler litter each year as a by-product for application on pasturelands. Grab samples of fecal coliform (FC) and fecal streptococcus (FS) were collected monthly between March and December 1996 and FC and E-coli samples were collected weekly between July and October 2001 at six sites on the Waffelo and Terrapin Creeks in Nacogdoches County, Texas to assess possible impacts of poultry litter application on bacterial water quality. Sites were grouped by three pairs with each pair consisting of one upstream site in predominantly forested area …
Mercury Concentrations In Streams Of East Texas, Mingteh Chang, Mark C. Cochran, R. Scott Beasley, Matthew W. Mcbroom
Mercury Concentrations In Streams Of East Texas, Mingteh Chang, Mark C. Cochran, R. Scott Beasley, Matthew W. Mcbroom
Faculty Publications
Recent studies on potential mercury (Hg) contamination of fish from East Texas lakes and waterways have caused concern about mercury levels in East Texas waters. Historical records of Hg concentrations in 33 East Texas streams showed that median concentrations for each stream segment were no different than other U.S. streams. All the means and medians for stream segments having at least 20 recorded measurements were less than Texas (2.4 µg/L) water quality standards. Water samples collected in December 1995 and March 1996 from 6 different stream sites in Nacogdoches County had concentrations similar to historical records. Due to biological magnification, …
Tetratricopeptide Repeat Motif-Mediated Hsc70-Msti1 Interaction Molecular Characterization Of The Critical Contacts For Successful Binding And Specificity*, Odutayo O. Odunuge, Judith A. Hornby, Chrisiane Bies, Richard Zimmermann, David J. Pugh, Gregory L. Blatch
Tetratricopeptide Repeat Motif-Mediated Hsc70-Msti1 Interaction Molecular Characterization Of The Critical Contacts For Successful Binding And Specificity*, Odutayo O. Odunuge, Judith A. Hornby, Chrisiane Bies, Richard Zimmermann, David J. Pugh, Gregory L. Blatch
Faculty Publications
Murine stress-inducible protein 1 (mSTI1) is a cochaperone that is homologous with the human Hsp70/ Hsp90-organizing protein (Hop). Guided by Hop structural data and sequence alignment analyses, we have used site-directed mutagenesis, co-precipitation assays, circular dichroism spectroscopy, steady-state fluorescence, and surface plasmon resonance spectroscopy to both qualitatively and quantitatively characterize the contacts necessary for the N-terminal tetratricopeptide repeat domain (TPR1) of mSTI1 to bind to heat shock cognate protein 70 (Hsc70) and to discriminate between Hsc70 and Hsp90. We have shown that substitutions in the first TPR motif of Lys8 or Asn12 did not affect binding of mSTI1 to Hsc70, …
Shape Imprinting Due To Variable Disulfide Bonds In Polyacrylamide Gels, Andrew B. Greytak, Alexander Y. Grosberg, Toyoichi Tanaka
Shape Imprinting Due To Variable Disulfide Bonds In Polyacrylamide Gels, Andrew B. Greytak, Alexander Y. Grosberg, Toyoichi Tanaka
Faculty Publications
Through the use of variable disulfide crosslinkers, we have created polyacrylamide gels whose shape can be altered after polymerization. N,N'-bisacryloylcystamine is incorporated as a crosslinker, along with a smaller amount of a permanent crosslinker. After polymerization, the disulfide bonds are cleaved into thiols through reduction. By reoxidizing the thiols with the gel held in a new macroscopic shape, a new set of disulfide bonds is formed, and the gel is forced to adopt the new shape. Retension of the new shape improves with greater distortion from the original shape, as well as with increased concentration of variable …
Process For Immobilizing Waste Using Bagasse (Us Patent 6174275), Michael A. Janusa
Process For Immobilizing Waste Using Bagasse (Us Patent 6174275), Michael A. Janusa
Faculty Publications
No abstract provided.
Nonsteroidal Anti-Inflammatory Drugs, Acetaminophen, Cyclooxygenase 2, And Fever, Daniel L. Simmons, David Wagner, Kenneth Westover
Nonsteroidal Anti-Inflammatory Drugs, Acetaminophen, Cyclooxygenase 2, And Fever, Daniel L. Simmons, David Wagner, Kenneth Westover
Faculty Publications
Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used antipyretic agents that most probably exert their antifever effect by inhibiting cyclooxygenase (COX)–2. Thus, COX-2–selective drugs or null mutation of the COX-2 gene reduce or prevent fever. Acetaminophen is antipyretic and analgesic, as are NSAIDs, but it lacks the anti-inflammatory and anticoagulatory properties of these drugs. This has led to the speculation that a COX variant exists that is inhibitable by acetaminophen. An acetaminophen-inhibitable enzyme is inducible in the mouse J774.2 monocyte cell line. Induction of acetaminophen-inhibitable prostaglandin E2 synthesis parallels induction of COX-2. Thus, inhibition of pharmacologically distinct COX-2 enzyme activity by …
The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan
The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan
Faculty Publications
The dipolar hard sphere fluid (DHSF) is a useful model of a polar fluid. However, the DHSF lacks a vapor–liquid transition due to the formation of chain-like structures. Such chains are not characteristic of real polar fluids. A more realistic model of a polar fluid is obtained by adding a Lennard–Jones potential to the intermolecular potential. Very similar results are obtained by adding a Yukawa potential, instead of the Lennard–Jones potential. We call this fluid the dipolar Yukawa fluid (DYF). We show that an analytical solution of the mean spherical approximation (MSA) can be obtained for the DYF. Thus, the …
Monte Carlo Study Of The Capacitance Of The Double Layer In A Model Molten Salt, Douglas Henderson, Dezso Boda, Kwong-Yu Chan
Monte Carlo Study Of The Capacitance Of The Double Layer In A Model Molten Salt, Douglas Henderson, Dezso Boda, Kwong-Yu Chan
Faculty Publications
Monte Carlo simulations are reported for charged hard spheres at high density near a charged wall. This system is a simple model for a molten salt double layer. Unfortunately, the reduced temperatures that correspond to experiment are very small. This results in a large Boltzmann factor. As a result, we are unable to obtain meaningful results for such low values and report results only for moderately low values of the reduced temperature. Even so, our results should be a useful benchmark. Further, we are able to give a qualitative answer to an interesting question. We find that at low temperatures …
Iron-Induced Oxidative Stress In Erythrocyte Membranes Of Non-Insulin-Dependent Diabetic Nigerians, Gbolahan W. Okunade, Odutayo O. Odunuge, Olufunso O. Olorunsogo
Iron-Induced Oxidative Stress In Erythrocyte Membranes Of Non-Insulin-Dependent Diabetic Nigerians, Gbolahan W. Okunade, Odutayo O. Odunuge, Olufunso O. Olorunsogo
Faculty Publications
The presence of higher level of endogenous free radical reaction products in the erythrocyte ghost membrane (EGM) of Non-insulin-dependent diabetes mellitus (NIDDM) subjects compared with that of normal healthy controls has been demonstrated. The EGMs of NIDDM subjects were also shown to be more susceptible to exogenously generated oxidative stress than those of normal healthy individuals. The decreased level of reactive thiol groups in the EGM of NIDDM individuals supported this observation. We propose that the presence of significant levels of non-heme iron in the EGM of NIDDM subjects is an indication of the potential for iron-catalysed production of hydroxy …
Reversal Of Sodium Arsenite Inhibition Of Rat Liver Microsomal Ca2+ Pumping Atpase By Vitamin C, Odutayo O. Odunuge, Gbolahan W. Okunade, Olufunso O. Olorunsogo
Reversal Of Sodium Arsenite Inhibition Of Rat Liver Microsomal Ca2+ Pumping Atpase By Vitamin C, Odutayo O. Odunuge, Gbolahan W. Okunade, Olufunso O. Olorunsogo
Faculty Publications
Sodium arsenite (NaAsO2), at 10% of its median lethal dose, was administered to rats with and without vitamin C pretreatment. Liver microsomal fraction was isolated and the activity of Ca2+-ATPase was assayed. Sodium arsenite was found to inhibit the activity of the liver microsomal Ca2+-ATPase to 50% to that of control rats. The specific activity of the enzyme in rats administered sodium arsenite with vitamin C pretreatment was not significantly different from that of control rats.
Some Aspects Of The Adsorption Of A Lennard-Jones Gas On A Rough Surface, Douglas Henderson, Pawel Bryk, Stefan Sokolowski
Some Aspects Of The Adsorption Of A Lennard-Jones Gas On A Rough Surface, Douglas Henderson, Pawel Bryk, Stefan Sokolowski
Faculty Publications
We study the adsorption, including wetting, of a Lennard-Jones gas on a rough surface consisting of rough layer on a smooth substrate with which the gas interacts via a 9-3 potential. The rough layer is two molecular diameters thick and consists of a disordered quenched matrix of hard spheres. As well as interacting with the other matrix spheres by the hard-sphere potential, the matrix molecules interact with the gas molecules by the hard-sphere potential. Hence, on average, the degree to which the gas molecules can approach the substrate depends only on the density of the matrix layer. The density of …
Monte Carlo Simulation Of An Ion-Dipole Mixture As A Model Of An Electrical Double Layer, Douglas Henderson, Dezso Boda, Kwong-Yu Chan
Monte Carlo Simulation Of An Ion-Dipole Mixture As A Model Of An Electrical Double Layer, Douglas Henderson, Dezso Boda, Kwong-Yu Chan
Faculty Publications
Canonical Monte Carlo simulations were performed for a nonprimitive model of an electrical double layer. The ions and the solvent molecules are modeled as charged and dipolar hard spheres, respectively, while the electrode as a hard, impenetrable wall carrying uniform surface charge. We found that the ion-dipole model gives a reasonable description of the double layer for partially charged ions with small to moderate dipole moments, or equivalently for an "effective" dielectric constant. Density, polarization and mean electrostatic potential profiles are reported. Strong layering structure, and at higher charges, charge inversion in the second layer were found. With appropriate choices …
Solute-Solvent Pair Distribution Functions In Highly Asymmetric Additive Hard Sphere Mixtures, Douglas Henderson, Kwong-Yu Chan
Solute-Solvent Pair Distribution Functions In Highly Asymmetric Additive Hard Sphere Mixtures, Douglas Henderson, Kwong-Yu Chan
Faculty Publications
Contact values for the solute-solvent pair distribution function in an additive hard sphere mixture, as computed from the Henderson-Chan (HC) formulas, are compared with the recent Monte Carlo (MC) data and formula of Matyushov and Ladanyi (ML) [J. Chem. Phys. 107, 5815 (1997)]. The agreement is found to be excellent. The negative finding of ML is due to a misprint in one of the HC publications. We find the HC formula to be superior to the ML formula when compared to our MC data [Mol. Phys. 91, 1137 (1997)] for the case where the ratio of diameters is large and …
A Fluid In Contact With A Semipermeable Surface: Second-Order Integral Equation Approach, Douglas Henderson, Pawel Bryk, Stefan Sokolowski
A Fluid In Contact With A Semipermeable Surface: Second-Order Integral Equation Approach, Douglas Henderson, Pawel Bryk, Stefan Sokolowski
Faculty Publications
An integral equation approach for a binary hard-sphere mixture interacting with a planar semipermeable wall (membrane) is formulated by using the second-order nonuniform or pair Ornstein–Zernike equation as well as the usual singlet Ornstein–Zernike equation. The results of the pair theory are compared with those obtained from the singlet theory and with computer simulation data. The pair approach is more accurate than the singlet theory.
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 …
234Th And 210Pb Evidence For Rapid Ingestion Of Settling Particles By Mobile Epibenthic Megafauna In The Abyssal Ne Pacific, L. M. L. Lauerman, J. M. Smoak, Timothy J. Shaw, W. S. Moore, K. L. Smith Jr.
234Th And 210Pb Evidence For Rapid Ingestion Of Settling Particles By Mobile Epibenthic Megafauna In The Abyssal Ne Pacific, L. M. L. Lauerman, J. M. Smoak, Timothy J. Shaw, W. S. Moore, K. L. Smith Jr.
Faculty Publications
No abstract provided.
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.
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 …
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
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.
Semiclassical Quantization Of A Nonintegrable System: Pushing The Fourier Method Into The Chaotic Regime, Karl Sohlberg, Randall B. Shirts
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 …
The Structure And Dynamics Of The Cs2 Molecular Ion, Karl Sohlberg, Chan Yibai
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 …
Comparison Of Dietary Overlap Between Allopatric And Sympatric Geckos, Paul D. Klawinski, R. Kathryn Vaughan, Daniel Saenz, William Godwin
Comparison Of Dietary Overlap Between Allopatric And Sympatric Geckos, Paul D. Klawinski, R. Kathryn Vaughan, Daniel Saenz, William Godwin
Faculty Publications
Two gecko species, Hemidactylus turcicus and Cyrtopodion scabrum, have been introduced into the Port of Galveston, Texas. While H. turcicus has been established for a longer period of time, the relatively recent introduction of C. scabrum near the entrance of the Port has apparently led to the displacement of H. turcicus in that area. This has resulted in a distribution in which the two populations’ are largely allopatric except for a narrow band of sympatry at the periphery of each of their ranges. We examined stomach contents of both species in allopatry and sympatry in order to determine if …
Sequence Alignment With Matched Sections, Jerrold R. Griggs, Philip J. Hanlon, Michael S. Waterman
Sequence Alignment With Matched Sections, Jerrold R. Griggs, Philip J. Hanlon, Michael S. Waterman
Faculty Publications
In molecular biology, two finite sequences are compared by displaying one sequence written over another in an alignment. The number of alignments of two sequences is related to the Stanton-Cowan numbers. This paper gives asymptotics for the number of alignments of two sequences of length n with matching sections of size at least b.