Physical Sciences and Mathematics Commons^™

Acrosome Reaction Is Subfamily Specific In Sea Star Fertilization, Mia Nakachi, Hideaki Moriyama, Motonori Hoshi, Midori Matsumoto

Hideaki Moriyama Publications

In the fertilization process of sea stars, sperm is activated to go through the acrosome reaction before cell fusion. We focused on induction of the acrosome reaction as a key process in fertilization. Six species of sea stars were used in this study: Asterias amurensis, Asterias rubens, Asterias forbesi, Aphelasterias japonica, Distolasterias nipon, and Asterina pectinifera. Acrosome reaction assays indicate that the acrosome reaction can be induced across species within Asteriinae subfamily. However, cross-fertilization assays indicate that sea stars have species specificity in fertilization. Therefore, steps after the acrosome reaction are responsible for the …

Microfabrication And Evaluation Of Planar Thin-Film Microfluidic Devices, Bridget Ann Peeni

Theses and Dissertations

Over the past 15 years, research in the field of microfluidics has rapidly gained popularity. By seeking to miniaturize and automate separation-based analysis, microfluidic research seeks to improve current methods through decreased cost, analysis time, and sources of contamination. My work has focused on developing a novel fabrication method, based on standard microfabrication techniques, to create thin-film microfluidic devices. This microfabrication format makes it possible to generate devices that provide high efficiencies, enable mass fabrication, and provide a platform capable of integrating the microfluidic and electronic components necessary for a micro-total analysis system (μ-TAS). Device fabrication combines the processes of …

Minutes: Council Meeting

Virginia Journal of Science

Minutes of the VAS Council meeting Friday May 26, 2006, 8 - 9:40 AM, at Skelton Conference Center Inn, Virginia Tech, Blacksburg VA. Minutes were edited for publication.

2004 Jeffress Research Grant Awards

Virginia Journal of Science

List of winners of the 2004 Jeffress Research Grant Awards.

Homogeneous Nucleation At High Supersaturation And Heterogeneous Nucleation On Microscopic Wettable Particles: A Hybrid Thermodynamic/Density-Functional Theory, T. V. Bykov, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Homogeneous nucleation at high supersaturation of vapor and heterogeneous nucleation on microscopic wettable particles are studied on the basis of Lennard-Jones model system. A hybrid classical thermodynamics and density-functional theory (DFT) approach is undertaken to treat the nucleation problems. Local-density approximation and weighted-density approximation are employed within the framework of DFT. Special attention is given to the disjoining pressure of small liquid droplets, which is dependent on the thickness of wetting film and radius of the wettable particle. Different contributions to the disjoining pressure are examined using both analytical estimations and numerical DFT calculation. It is shown that van der …

Chemistry & Biochemistry Newsletter, Department Of Chemistry & Biochemistry, South Dakota State University

Chemistry & Biochemistry Newsletter: 2002-2015

Inside:

Page 2-3 Grad students attend International Summer School in Green Chemistry

Page 3 Alumni News

Page 4 Alum receives brigadier general stars

Page 5 New Grad Students

Page 6 Tanaka endows undergraduate scholarship; Midwest Seeds becomes internship partner

Page 7 The 2006/2007 Burris Lecturer leader in drug discovery

Page 8 New Faculty; Perfecting the formula for the future of SDSU chemistry

Anaerobic Catalytic Oxidation Of Hydrocarbons In Moving Heat Waves. Case Simulation: Propane Oxidative Dehydrogenation In A Packed Adiabatic V-Ti Oxide Catalyst Bed, Andrey N. Zagoruiko

Andrey N Zagoruiko

The model simulation study has shown that the anaerobic process of oxidative dehydrogenation of propane under periodic alteration of feeding between propane and air may be realized in adiabatic catalyst beds in stable continuous cyclic mode in two-reactor scheme. In case of appropriate choice of process parameters (cycle duration, feeding flow rates) the process appears to be autothermal, i.e. it does not require any inlet gas preheating for stable operation. Compared to similar steady-state adiabatic process, the proposed process is characterized with much lower maximum catalyst temperatures, giving the way to process pure propane without diluting it with inert gases, …

Semicrystalline Thermoplastic Elastomeric Polyolefins: Advances Through Catalyst Development And Macromolecular Design, Atsushi Hotta, Eric W. Cochran, Janne Ruokolainen, Vikram Khann, Glenn H. Fredrickson, Edward J. Kramer, Yong-Woo Shin, Fumihiko Shimizu, Anna E. Cherian, Phillip D. Hustad, Jeffrey M. Rose, Geoffrey W. Coates

Eric W. Cochran

We report the design, synthesis, morphology, phase behavior, and mechanical properties of semicrystalline, polyolefin-based block copolymers. By using living, stereoselective insertion polymerization catalysts, syndiotactic polypropylene-block-poly(ethylene-co-propylene)-block-syndiotactic polypropylene and isotactic poly propylene-block-regioirregular poly propylene-block- isotactic polypropylene triblock copolymers were synthesized. The volume fraction and composition of the blocks, as well as the overall size of the macromolecules, were controlled by sequential synthesis of each block of the polymers. These triblock copolymers, with semicrystalline end-blocks and mid-segments with low glass-transition temperatures, show significant potential as thermoplastic elastomers. They have low Young's moduli, large strains at break, and better than 90% elastic recovery at …

Hydrogen And Deuterium Exchange On Pt(111) And Its Poisoning By Carbon Monoxide Studied By Surface Sensitive High-Pressure Techniques, Max Montano, Kaitlin M. Bratlie, Miquel Salmeron, Gabor A. Somorjai

Kaitlin M. Bratlie

Catalytic hydrogen/deuterium exchange on a platinum (111) single crystal and its poisoning with carbon monoxide was studied using scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), sum frequency generation vibrational spectroscopy (SFG), and mass spectrometry under reaction conditions at pressures in the mTorr to atmospheric range. At 298 K and in the presence of 200 mTorr of hydrogen and 20 mTorr of deuterium the surface is catalytically active, producing HD with activation energy of 5.3 kcal/mol. Addition of 5 mTorr of CO stops the reaction completely. In situ STM images reveal an ordered surface structure of chemisorbed CO. At 353 …

Occlusion Of Grubbs' Catalysts In Active Membranes Of Polydimethylsiloxane:  Catalysis In Water And New Functional Group Selectivities, Martin T. Mwangi, M. Brett Runge, Ned B. Bowden

Martin M. Thuo

The Grubbs' first and second generation catalysts were occluded into cross-linked slabs of polydimethylsiloxane with volumes from 1 mm3 to 1 cm3 by swelling the polymer with catalyst and methylene chloride. Methylene chloride was evaporated under vacuum to yield occluded catalysts where their solvent was polydimethylsiloxane. These occluded catalysts were reacted with alkenes dissolved in H2O or H2O/MeOH mixtures that diffused into the polydimethylsiloxane to react by ring-closing metathesis and cross metathesis. Control experiments revealed that the catalysts remained occluded and metathesis did not occur in the solvent. Occlusion of these catalysts allowed commercially available Grubbs' catalysts to be used …

Sum Frequency Generation Vibrational Spectroscopic And High-Pressure Scanning Tunneling Microscopic Studies Of Benzene Hydrogenation On Pt(111), Kaitlin M. Bratlie, Max O. Montano, Lucio D. Flores, Matti Paajanen, Gabor A. Somorjai

Kaitlin M. Bratlie

Sum frequency generation (SFG) vibrational spectroscopy and high-pressure scanning tunneling microscopy (HP-STM) have been used in combination for the first time to study a catalytic reaction. These techniques have been able to identify surface intermediates in situ during benzene hydrogenation on a Pt(111) single-crystal surface at Torr pressures.

Structures And Relative Stability Of Neutral Gold Clusters: AuN (N=15–19), Satya S. Bulusu, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

We performed a global-minimum search for low-lying neutral clusters (Au_n) in the size range of n=15–19 by means of basin-hopping method coupled with density functional theory calculation. Leading candidates for the lowest-energy clusters are identified, including four for Au₁₅, two for Au₁₆, three for Au₁₇, five for Au₁₈, and one for Au₁₉. For Au₁₅ and Au₁₆ we find that the shell-like flat-cage structures dominate the population of low-lying clusters, while for Au₁₇ and Au₁₈ spherical-like hollow-cage structures dominate the low-lying population. The transition …

Additional Evidence For The Migration Of Clay Upon Heating Of Clay–Polypropylene Nanocomposites From X-Ray Photoelectron Spectroscopy (Xps), Jianwei Hao, Menachem Lewin, Charles A. Wilkie, Jiangqi Wang

Chemistry Faculty Research and Publications

The explanation for reduction in the peak heat release rate of polymer–clay nanocomposites which is normally accepted is that clay accumulates at the surface, forming a thermal shield which is also a barrier to mass transport. The process by which this clay arrives at the surface has never been described in print but the common assumption is that pyrolysis is required for clay accumulation to occur. In this work, X-ray photoelectron spectroscopy, a tool much more sensitive in surface analysis than conventional techniques, is used to probe the surface of polypropylene–clay nanocomposites that have been annealed at relatively low temperatures, …

A New Colorimetric Assay For Methionyl Aminopeptidases: Examination Of The Binding Of A New Class Of Pseudopeptide Analog Inhibitors, Sanghamitra Mitra, Anna M. Dygas-Holz, Jiri Jiracek, Miroslava Zertova, Lenka Zakova, Richard C. Holz

Chemistry Faculty Research and Publications

A direct and convenient spectrophotometric assay has been developed for methionine aminopeptidases (MetAPs). The method employs the hydrolysis of a substrate that is a methionyl analogue of p-nitroaniline (l-Met-p-NA), which releases the chromogenic product p-nitroaniline. This chromogenic product can be monitored continuously using a UV–Vis spectrophotometer set at 405 nm. The assay was tested with the type I MetAP from Escherichia coli (EcMetAP-I) and the type II MetAP from Pyrococcus furiosus (PfMetAP-II). Using l-Met-p-NA, the kinetic constants k_cat and K_m were determined for EcMetAP-I and PfMetAP-II …

Afci Quarterly Input – Unlv July 1 Through September 30, 2006, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division

Transmutation Research Program Reports (TRP)

Quarterly report highlighting research projects, activities and objectives of the Transmutation Research Program at the Nuclear Science & Technology Division, Harry Reid Research Center.

The University of Nevada, Las Vegas supports the AFCI through research and development of technologies for economic and environmentally sound refinement of spent nuclear fuel. The UNLV program has four components: infrastructure, international collaboration, student-based research, and management and program support.

Sequence-Specific Recognition And Cooperative Dimerization Of N-Terminal Aromatic Peptides In Aqueous Solution By A Synthetic Host, Lisa M. Heitmann, Alexander B. Taylor, P John Hart, Adam R. Urbach

Chemistry Faculty Research

This article describes the selective recognition and noncovalent dimerization of N-terminal aromatic peptides in aqueous solution by the synthetic host compound, cucurbit[8]uril (Q8). Q8 is known to bind two aromatic guests simultaneously and, in the presence of methyl viologen, to recognize N-terminal tryptophan over internal and C-terminal sequence isomers. Here, the binding of Q8 to aromatic peptides in the absence of methyl viologen was studied by isothermal titration calorimetry (ITC), ¹H NMR spectroscopy, and X-ray crystallography. The peptides studied were of sequence X-Gly-Gly, Gly-X-Gly, and Gly-Gly-X (X = Trp, Phe, Tyr, and His). Q8 selectively binds and dimerizes Trp-Gly-Gly …

Studies On Cyclooxygenase-1, Its Structure And Splice Variants, And Modulation Of Cyclooxygenase-2 By Inducible Nitric Oxide Synthase And Novel Phytochemicals., Yibing Xu

Theses and Dissertations

Cyclooxygenases (COXs) are of important therapeutic value as they are the target site of aspirin-like drugs. Here I report nine new COX-1 splice variants in chapter 1, which I characterized with regard to heme-binding and other properties. Inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) are co-inducible in many tissues following mitogenic and proinflammatory stimulation. In chapter 2, I investigate the physical and enzymatic properties of human COX-2 and iNOS and demonstrate that, despite reports to the contrary by another laboratory, they do not interact. The only reported COX-1 splice variant to exhibit cyclooxygenase activity has been isolated from …

A 2:1 Complex Of 1,3-Bis­(9h-Carbazol-9-Yl)Propane And Tetra­Chloro-P-Benzoquinone (P-Chloranil), Mustafa Arslan, Randolph B. Krafcik, John Masnovi, Ronald J. Baker

Chemistry Faculty Publications

In the title electron donor–acceptor complex, C₂₇H₂₂N₂·0.5C₆Cl₄O₂, the p-chloranil mol­ecule lies on a crystallographic inversion center, which is located at the center of the benzene ring. In the crystal structure, one p-chloranil mol­ecule lies above and below the central rings of each donor group of two neighboring 1,3-bis­(9H-carbazol-9-yl)propane mol­ecules, with a ring-centroid separation of 3.444 (1) Å. The angle between the planes of the stacking rings of the carbazole and p-chloranil mol­ecules is 3.4 (2)°.

(E,E)-1,3-Bis[9,10-Dihydro-9-Nitro-10-(Trinitro­Meth­Yl)-9-Anthr­Yl]Propane, Mustafa Arslan, Erol Asker, John Masnovi, Ronald J. Baker

Chemistry Faculty Publications

The title compound, C₃₃H₂₄N₈O₁₆, was obtained as a product of the photoreaction between 1,3-di-9-anthrylpropane and tetra­nitro­methane. The mol­ecule occupies a special position on a twofold axis. The trinitro­methyl and nitro substituents on the 9,10-dihydro­acridine system are E oriented.

Cleavage Of Phosphate Ester Bonds By Use Of Novel Group 13 Chelate Compounds, David A. Atwood

Chemistry Faculty Patents

A novel chemical compound has a general formula (LX)_nY wherein X is selected from a group consisting of a group 13 element other than boron, Y is selected from a group consisting of a halide, a chlorate, a sulfate and a nitrate and L is a chelating ligand containing two nitrogen and two oxygen donor groups where n=1 or 2.

Novel Mesoscale Defect Structure On Nio(1 0 0) Surfaces By Atomic Force Microscopy, S. C. Petitto, Cindy L. Berrie, Marjorie Langell

Marjorie A. Langell Publications

Cleaved NiO(1 0 0) surfaces were imaged with atomic force microscopy (AFM) to determine defect concentrations and morphology. Random (0 1 0) and (0 0 1) oriented steps, which have been previously characterized, were the most common defect observed on the cleaved surface and formed with step heights in multiples of 2.1 Å, the Ni–O nearest-neighbor distance, and terrace widths in the range of 25–100 nm. In addition, the surface showed novel mesoscale (~0.5–2 μm) square pyramidal defects with the pyramid base oriented along (1 0 0) symmetry related directions. Upon etching, the pyramidal defects converted to more stable cubic …

Absorption Properties Of A Porous Organic Crystalline Apohost Formed By A Self-Assembled Bis-Urea Macrocycle, Mahender B. Dewal, Michael W. Lufaso, Andrew D. Hughes, Stevan A. Samuel, Perry J. Pellechia, Linda S. Shimizu

Faculty Publications

We report herein the characterization and binding properties of a microporous crystalline host formed by the self assembly of a bis-urea macrocycle 1. Bis-urea macrocycle 1 has been designed to crystallize into stacked hollow columns. The self-assembly process is guided primarily by hydrogen bonding and aromatic stacking interactions that yield crystals of filled host 1âacetic acid (AcOH). The AcOH guests are bound in the cylindrical cavities of the crystal. The guest AcOH can be removed by heating to form a stable crystalline apohost 1. Apohost 1 displays a type I gas adsorption isotherm with CO₂ that is consistent with …

Tau-Tubulin Kinase 1 (Ttbk1), A Neuron-Specific Tau Kinase Candidate, Is Involved In Tau Phosphorylation And Aggregation, Shinji Sato, Ronald Cerny, James L. Buescher, Tsuneya Ikezu

Ronald Cerny Publications

Neurofibrillary tangles, which are major pathological hallmarks of Alzheimer’s disease (AD), are composed of paired helical filaments (PHFs) containing hyperphosphorylated tau. Specific kinases regulate tau phosphorylation and are closely linked to the pathogenesis of AD. We have characterized a human tau-tubulin kinase 1 (TTBK1) gene located on chromosome 6p21.1. TTBK1 is a serine/threonine/tyrosine kinase that is conserved among species and belongs to the casein kinase 1 superfamily. It is specifically expressed in the brain, especially in the cytoplasm of cortical and hippocampal neurons. TTBK1 phosphorylates tau proteins in both a Mg²⁺- and a Mn²⁺-dependent manner. Phosphopeptide …

Single-Crystal, Polarized, Raman Scattering Study Of The Molecular And Lattice Vibrations For The Energetic Material Cyclotrimethylene Trinitramine, James C. Haycraft, Lewis L. Stevens, Craig J. Eckhardt

Craig J. Eckhardt Publications

The single-crystal, polarized, Raman spectra for cyclotrimethylene trinitramine (RDX) have been studied at room temperature and pressure over the region of 5–3400 cm^-1. While the observed Raman bands agree well with a previous Raman study, this work provides a consistent interpretation of the Raman spectra by assignment of fundamental modes, overtones, and combination bands. A total of 56 internal vibrations were observed, 36 of which were labeled as fundamental molecular vibrations. In addition, all 24 lattice optical phonons are identified. All six possible polarizations were probed to obtain the A_g, B_1g, B_{2 …}

“Reductive Ozonolysis” Via A New Fragmentation Of Carbonyl Oxides, Chris Schwartz, Joseph Raible, Kyle Mott, Patrick Dussault

Patrick Dussault Publications

This account describes the development of methodologies for ‘reductive’ ozonolysis, the direct ozonolytic conversion of alkenes into carbonyl groups without the intermediacy of 1,2,4-trioxolanes (ozonides). Ozonolysis of alkenes in the presence of DMSO produces a mixture of aldehyde and ozonide. The combination of DMSO and Et₃N results in improved yields of carbonyls but still leaves unacceptable levels of residual ozonides; similar results are obtained using secondary or tertiary amines in the absence of DMSO. The influence of amines is believed to result from conversion to the corresponding N-oxides; ozonolysis in the presence of amine N-oxides efficiently …

Structure Effects Of Benzene Hydrogenation Studied With Sum Frequency Generation Vibrational Spectroscopy And Kinetics On Pt(111) And Pt(100) Single-Crystal Surfaces, Kaitlin M. Bratlie, Christopher J. Kliewer, Gabor A. Somorjai

Kaitlin M. Bratlie

Sum frequency generation (SFG) surface vibrational spectroscopy and kinetic measurements using gas chromatography have identified at least two reaction pathways for benzene hydrogenation on the Pt(100) and Pt(111) single-crystal surfaces at Torr pressures. Kinetic studies at low temperatures (310-370 K) show that benzene hydrogenation does not proceed through cyclohexene. A Langmuir-Hinshelwood-type rate law for the low-temperature reaction pathway is identified. The rate-determining step for this pathway is the addition of the first hydrogen atom to adsorbed benzene for both single-crystal surfaces, which is verified by the spectroscopic observation of adsorbed benzene at low temperatures on both the Pt(100) and Pt(111) …

Posterminaries: The Scales Of Judgement, Alexander H. King

Alexander H. King

Materials scientists are generally well-versed in physics, and physics, above all, is a science of measurements. The first instinct of a physicist is to parse a problem in terms of its measurables in the dimensions of mass, length, and time, and it is the shifting of attention down the scale of length that particularly characterizes our present times as the Nano Age.

N-(2-Aminobenzyl)-N,N-Bis(Quinolin- 2-Ylmethyl)Amine, Abhijit Mitra, Pamela J. Seaton, Kraig A. Wheeler

Kraig A. Wheeler

The title new diquinaldine derivative, C27H24N4, forms mol­ecular assemblies organized by inter­molecular quinoline π–π stacking [3.356 (3) and 3.440 (3) Å] and both inter- and intra­molecular N—H⋯N hydrogen bonds [3.039 (3)–3.104 (3) Å and 129 (2)–172 (2)°]. The combination of such inter­actions provides readily definable contacts that propagate along each crystallographic axis.

Significance Of Polycyclic Aromatic Hydrocarbons (Pahs) And Petroleum Biomarker Compounds In Contaminated Passaic River Sediments, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The lower Passaic River (northeastern New Jersey) flows through one of the most densely populated regions of the United States. The area’s long history of industrial activity is reflected in the complex and variable hydrocarbon composition of the river sediments. Sediments from river bottom grab samples at Newark and a 30 cm deep core at Kearny were subjected to thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). This technique offers a practical alternative for rapid, inexpensive analysis, simply employing milligram quantities of dry, disaggregated sediment, avoiding the use of hazardous organic solvents. For each sample, a total of 181 hydrocarbons and organosulfur compounds …

N-(2-Aminobenzyl)-N,N-Bis(Quinolin- 2-Ylmethyl)Amine, Abhijit Mitra, Pamela J. Seaton, Kraig A. Wheeler

Faculty Research and Creative Activity

The title new diquinaldine derivative, C27H24N4, forms mol­ecular assemblies organized by inter­molecular quinoline π–π stacking [3.356 (3) and 3.440 (3) Å] and both inter- and intra­molecular N—H⋯N hydrogen bonds [3.039 (3)–3.104 (3) Å and 129 (2)–172 (2)°]. The combination of such inter­actions provides readily definable contacts that propagate along each crystallographic axis.