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Articles 3301 - 3330 of 3948
Full-Text Articles in Chemistry
Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan
Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan
Faculty Publications
Exact results in any field, including statistical mechanics, are both aesthetically pleasing and very valuable in assessing theoretical approximations.
4-Hydroxyphenylretinamide (4hpr) Derivatives Regulate Aromatase Activity And Expression In Breast Cancer Cells, Bin Su, Serena M. Mershon, Laura A. Stonerock, Robert W. Curley Jr., Robert W. Brueggemeier
4-Hydroxyphenylretinamide (4hpr) Derivatives Regulate Aromatase Activity And Expression In Breast Cancer Cells, Bin Su, Serena M. Mershon, Laura A. Stonerock, Robert W. Curley Jr., Robert W. Brueggemeier
Chemistry Faculty Publications
Recent studies exhibit that 4-hydroxyphenylretinamide (4HPR) decreases aromatase activity in breast and placental cells. The effect of synthetic 4HPR analogs on aromatase and expression was examined in three breast cancer cell lines. Most derivatives did not decrease cellular aromatase activity. Two of the analogs even stimulated aromatase activity at the transcriptional level. Only one derivative significantly decreased aromatase in all three breast cancer cell lines and also suppressed CYP19 gene expression in one of the cell line. Placental microsomal aromatase assay rule out the possibility that this compound directly inhibits the aromatase enzyme. A non-genomic mechanism in suppression of cellular …
4-(4-Chlorophenyl)-5-[1-(4-Chlorophenyl)-2-Methyl-2-Nitropropyl]-1,2,3-Selenadiazole, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam Rath
4-(4-Chlorophenyl)-5-[1-(4-Chlorophenyl)-2-Methyl-2-Nitropropyl]-1,2,3-Selenadiazole, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam Rath
Chemistry & Biochemistry Faculty Works
In the title compound, C18H15Cl2N3O2Se, the selenadiazole ring makes dihedral angles of 49.87 (3) and 55.70 (3)° with the two benzene rings. The dihedral angle between the two benzene rings is 11.90 (5)°. In the crystal structure, intramolecular C-H...O and C-H...Se interactions and intermolecular C-H...O, C-H...Cl and C-H...N interactions are observed.
Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy
Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy
Faculty Publications
Relaxation of highly vibrationally excited pyrimidine (C4N2H4) by collisions with carbon dioxide has been investigated using diode laser transient absorption spectroscopy. Vibrationally hot pyrimidine (E'=40,635 cm^-1) was prepared by 248-nm excimer laser excitation, followed by rapid radiationless relaxation to the ground electronic state. The nascent rotational population distribution (J=58–80) of the 0000 ground state of CO2 resulting from collisions with hot pyrimidine was probed at short times following the excimer laser pulse. Doppler spectroscopy was used to measure the CO2 recoil velocity distribution for J=58–80 of the 0000 state. Rate constants and probabilities for collisions populating these CO2 rotational states …
Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu
Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu
Faculty Publications
Exposure to ozone, which is a major component of air pollution, induces a form of asthma that occurs in the absence of adaptive immunity. Although ozone-induced asthma is characterized by airway neutrophilia, and not eosinophilia, it is nevertheless associated with airway hyperreactivity (AHR), which is a cardinal feature of asthma. Because AHR induced by allergens requires the presence of natural killer T (NKT) cells, we asked whether ozone-induced AHR had similar requirements. We found that repeated exposure of wild-type (WT) mice to ozone induced severe AHR associated with an increase in airway NKT cells, neutrophils, and macrophages. Surprisingly, NKT cell-deficient …
Protein Adsorption Onto Organically-Modified Silica Glass Leads To A Different Structure Than Sol-Gel Encapsulation, Daryl K. Eggers, B, Menaa, C. Torres, M. Herrero, V. Rives, A. R.W Gilbert
Protein Adsorption Onto Organically-Modified Silica Glass Leads To A Different Structure Than Sol-Gel Encapsulation, Daryl K. Eggers, B, Menaa, C. Torres, M. Herrero, V. Rives, A. R.W Gilbert
Faculty Publications, Chemistry
The secondary structures of two proteins were examined by circular dichroism spectroscopy after adsorption onto a series of organically modified silica glasses. The glasses were prepared by the sol-gel technique and were varied in hydrophobicity by incorporation of 5% methyl, propyl, trifluoropropyl, or n-hexyl silane. Both cytochrome c and apomyoglobin were found to lose secondary structure after adsorption onto the modified glasses. In the case of apomyoglobin, the α-helical content of the adsorbed protein ranged from 21% to 28%, well below the 62% helix found in solution. In contrast, these same glasses led to a striking increase in apomyoglobin structure …
Flash: A Rapid Method For Prototyping Paper-Based Microfluidic Devices, Andres W. Martinez, Scott T. Phillips, Benjamin J. Wiley, Malancha Gupta, George M. Whitesides
Flash: A Rapid Method For Prototyping Paper-Based Microfluidic Devices, Andres W. Martinez, Scott T. Phillips, Benjamin J. Wiley, Malancha Gupta, George M. Whitesides
Chemistry and Biochemistry
This article describes FLASH (Fast Lithographic Activation of Sheets), a rapid method for laboratory prototyping of microfluidic devices in paper. Paper-based microfluidic devices are emerging as a new technology for applications in diagnostics for the developing world, where low cost and simplicity are essential. FLASH is based on photolithography, but requires only a UV lamp and a hotplate; no clean-room or special facilities are required (FLASH patterning can even be performed in sunlight if a UV lamp and hotplate are unavailable). The method provides channels in paper with dimensions as small as 200 μm in width and 70 μm in …
Favourable Influence Of Hydrophobic Surfaces On Protein Structure In Porous Organically-Modified Silica Glasses, Daryl K. Eggers, B. Menaa, M. Herrero, V. Rives, M. Lavrenko
Favourable Influence Of Hydrophobic Surfaces On Protein Structure In Porous Organically-Modified Silica Glasses, Daryl K. Eggers, B. Menaa, M. Herrero, V. Rives, M. Lavrenko
Faculty Publications, Chemistry
Organically-modified siloxanes were used as host materials to examine the influence of surface chemistry on protein conformation in a crowded environment. The sol–gel materials were prepared from tetramethoxysilane and a series of monosubstituted alkoxysilanes, RSi(OR′)3, featuring alkyl groups of increasing chain length in the R-position. Using circular dichroism spectroscopy in the far-UV region, apomyoglobin was found to transit from an unfolded state to a native-like helical state as the content of the hydrophobic precursor increased from 0 to 15%. At a fixed molar content of 5% RSi(OR′)3, the helical structure of apomyoglobin increased with the chain length of the R-group, …
The Tropical Forest And Fire Emissions Experiment: Laboratory Fire Measurements And Synthesis Of Campaign Data, Robert J. Yokelson, Ted J. Christian, T. G. Karl, Alex Guenther
The Tropical Forest And Fire Emissions Experiment: Laboratory Fire Measurements And Synthesis Of Campaign Data, Robert J. Yokelson, Ted J. Christian, T. G. Karl, Alex Guenther
Chemistry and Biochemistry Faculty Publications
As part of the Tropical Forest and Fire Emissions Experiment (TROFFEE), tropical forest fuels were burned in a large. biomass-fire simulation facility and the smoke was characterized with open-path Fourier transform infrared spectroscopy (FTIR), proton-transfer reaction mass spectrometry (PTR-MS), gas chromatography (GC), GC/PTR-MS, and filter sampling of the particles. In most cases, about one-third of the fuel chlorine ended up in the particles and about one-half remained in the ash. About 50% of the mass of non-methane organic compounds (NMOC) emitted by these fires could be identified with the available instrumentation. The lab fire emission factors (EF, g compound emitted …
Open Circuit Potential Shifts Of Activated Carbon In Aqueous Solutions During Chemical And Adsorption Interactions, Mikhail M. Goldin, Vladimir A. Kolesnikov, Mogely Sh. Khubutiya, Alexander G. Volkov, Gary J. Blanchard, Anatoly K. Evseev, Mark M. Goldin
Open Circuit Potential Shifts Of Activated Carbon In Aqueous Solutions During Chemical And Adsorption Interactions, Mikhail M. Goldin, Vladimir A. Kolesnikov, Mogely Sh. Khubutiya, Alexander G. Volkov, Gary J. Blanchard, Anatoly K. Evseev, Mark M. Goldin
Faculty Publications and Presentations
Interaction of certain inorganic and organic compounds with activated carbon and the effect of such interaction on open circuit potential of activated carbon were studied. Open circuit potential shifts were observed for an overwhelming majority of the substances and brands of activated carbons investigated. Both negative and positive potential shifts were observed. It was shown that open circuit potential shifts for organic substances depend on degree of coverage of the activated carbon surface. Whereas adsorption of investigated organic compound on activated carbon led to positive potential shifts, desorption of adsorbates from the activated carbon surface led to potential shifts in …
Mutational Analysis Of The Stability Of The H2a And H2b Histone Monomers, Matthew R. Stump, Lisa M. Gloss
Mutational Analysis Of The Stability Of The H2a And H2b Histone Monomers, Matthew R. Stump, Lisa M. Gloss
Faculty Publications - Department of Biological & Molecular Science
The eukaryotic histone heterodimer H2A–H2B folds through an obligatory dimeric intermediate that forms in a nearly diffusion-limited association reaction in the stopped-flow dead time. It is unclear whether there is partial folding of the isolated monomers before association. To address the possible contributions of structure in the monomers to the rapid association, we characterized H2A and H2B monomers in the absence of their heterodimeric partner. By far-UV circular dichroism, the H2A and H2B monomers are 15% and 31% helical, respectively—significantly less than observed in X-ray crystal structures. Acrylamide quenching of the intrinsic Tyr fluorescence was indicative of tertiary structure. The …
Dms Air/Sea Flux And Gas Transfer Coefficients From The North Atlantic Summertime Coccolithophore Bloom, Christa Marandino, Warren J. De Bruyn, Scott Miller, Eric S. Saltzman
Dms Air/Sea Flux And Gas Transfer Coefficients From The North Atlantic Summertime Coccolithophore Bloom, Christa Marandino, Warren J. De Bruyn, Scott Miller, Eric S. Saltzman
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Dimethylsulfide (DMS) atmospheric and oceanic concentrations and eddy covariance air/sea fluxes were measured over the N. Atlantic Ocean during July 2007 from Iceland to Woods Hole, MA, USA. Seawater DMS levels north of 55 degrees N ranged from 3 to 17 nM, with variability related to the satellite-derived distributions of coccoliths and to a lesser extent, chlorophyll. For the most intense bloom region southwest of Iceland, DMS air/sea fluxes were as high as 300 mu mol m(-2) d(-1), larger than current model estimates. The observations imply that gas exchange coefficients in this region are significantly greater than those estimated using …
Polyaniline Nanofiber-Based Gas Sensors, Zhe-Fei Li, Frank D. Blum, Massimo F. Bertino, Chang-Soo Kim
Polyaniline Nanofiber-Based Gas Sensors, Zhe-Fei Li, Frank D. Blum, Massimo F. Bertino, Chang-Soo Kim
Chemistry Faculty Research & Creative Works
There has been recent interest in conducting polymers that have very promising chemical and electrical applications. Some of these polymers have shown great potential for use in sensors.1 Polyaniline is one particular example of a prospective material. In our laboratory, we have studied the synthesis of polyaniline nanofibers. We have carried out one-pot syntheses to obtain polyaniline nanofibers in aqueous solutions where the polymerization was influenced by γ-radiation2 or UV-radiation.3 This polymer can also be patterned with an appropriate photo mask. In our present report, polyaniline nanofiber thin film sensors have been fabricated in one step by employing UV-irradiation and …
Naturally Present Fatty Acids As Internal Calibrants For Fourier Transform Mass Spectra Of Dissolved Organic Matter, Rachel L. Sleighter, Georgina A. Mckee, Zhanfei Liu, Patrick G. Hatcher
Naturally Present Fatty Acids As Internal Calibrants For Fourier Transform Mass Spectra Of Dissolved Organic Matter, Rachel L. Sleighter, Georgina A. Mckee, Zhanfei Liu, Patrick G. Hatcher
Chemistry & Biochemistry Faculty Publications
The analysis of dissolved organic matter ( DOM) by Fourier transform ion cyclotron resonance mass spectrometry ( FTICR- MS) has gained wide interest recently, driven primarily by its ultrahigh resolving power and mass accuracy. Accurate calibration of mass spectra is a key step to successfully decipher the DOM components. We propose a simple and accurate method to internally calibrate the peaks in the complex spectra without the need to add a calibrant. Mass spectra of DOM samples from the Dismal Swamp, Virginia, and the lower Chesapeake Bay display the presence of naturally occurring fatty acids which can be readily recognized …
Salt Marshes As A Source Of Chromophoric Dissolved Organic Matter (Cdom) To Southern California Coastal Waters, Catherine D. Clark, Liannea P. Litz, Stanley B. Grant
Salt Marshes As A Source Of Chromophoric Dissolved Organic Matter (Cdom) To Southern California Coastal Waters, Catherine D. Clark, Liannea P. Litz, Stanley B. Grant
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
To determine chromophoric dissolved organic matter (CDOM) sources in Southern California coastal waters, optical properties of a river outlet and adjacent tidally flushed salt marshes were monitored (dry season; June July 2001). Average absorption coefficients doubled at ebb vs. flood tides (4.8 +/- 1.5 vs. 2.1 +/- 0.9 m(-1); 300 nm), suggesting significant salt marsh CDOM inputs into coastal waters. Average spectral slopes were not statistically different for any sites or tides (0.010 +/- 0.002 nm(-1)), consistent with salt marsh CDOM dominating coastal waters. Three-dimensional fluorescence excitation-emission matrices (EEMs) at ebb tide showed contributions from terrestrial, protein, and marine humic-like …
7Β-HydroxyArtemisinin, Paulo B. Carvalho, Bo Liu, Yunshan Wu, John S. Williamson, Mitchell A. Avery
7Β-HydroxyArtemisinin, Paulo B. Carvalho, Bo Liu, Yunshan Wu, John S. Williamson, Mitchell A. Avery
Office for Research Publications and Presentations
Crystals of the title compound [systematic name: (3R,6R,7S,8aR,9R,12aR)-7-hydroxy-3,6,9-trimethyloctahydro-3,12-epoxy[1,2]dioxepino[4,3-i]isochromen-10(3H)-one], C15H22O6, were obtained from microbial transformation of artemisinin by a culture of Cunninghamella elegans. The stereochemistry of the compound is consistent with the spectroscopic findings in previously published works. A weak O—H⋯O hydrogen bond occurs in the crystal structure, together with intermolecular C—H⋯O hydrogen bonds.
In-Vivo Delivery Of Dna Vaccines Using Metallo-Lipid Nanoparticles, Clarissa Sara Gomez
In-Vivo Delivery Of Dna Vaccines Using Metallo-Lipid Nanoparticles, Clarissa Sara Gomez
Open Access Theses & Dissertations
There has been a rapidly growing area of research in the design and synthesis of molecules that self-organize in water to form functional nanosystems and due to the high interest in the area metal ligand complexes were tested as drug delivery systems with a Leishmania vaccine. Herein, we present the design, synthesis and functional activity of Cu(II) and Zn(II) complexes that self-assemble in water to form spherical nanoscale structures that exhibit an affinity to bind DNA and deliver it into eukaryotic cells with a high percent efficiency in-vitro. In order to assess the effectiveness of these nanoparticles to deliver DNA …
Editorial, First Science And Policy Issue, Jscas
Editorial, First Science And Policy Issue, Jscas
Journal of the South Carolina Academy of Science
No abstract provided.
A Call For A Statewide Bioinformatics Institute, John R. Rose
A Call For A Statewide Bioinformatics Institute, John R. Rose
Journal of the South Carolina Academy of Science
No abstract provided.
With The Help Of South Carolina Research Universities, Scra Demonstrates Leadership In Applied Research And Commercialization Within Sc, Bill Mahoney
Journal of the South Carolina Academy of Science
No abstract provided.
Sc Inbre: A Catalyst For Biomedical Research Development In South Carolina, Lucia A. Pirisi-Creek M.D, Scott Little, Ph.D.
Sc Inbre: A Catalyst For Biomedical Research Development In South Carolina, Lucia A. Pirisi-Creek M.D, Scott Little, Ph.D.
Journal of the South Carolina Academy of Science
No abstract provided.
Inflammation: The Key To Health And Disease, Prakash Nagarkatti Ph. D, Donald J. Dipette M. D.
Inflammation: The Key To Health And Disease, Prakash Nagarkatti Ph. D, Donald J. Dipette M. D.
Journal of the South Carolina Academy of Science
No abstract provided.
Thermoelectric Applications For Imaging Infrared Focal Plane Arrays, Roy T. Littleton
Thermoelectric Applications For Imaging Infrared Focal Plane Arrays, Roy T. Littleton
Journal of the South Carolina Academy of Science
No abstract provided.
Solution Chemical Synthesis Of Nanostructured Thermoelectric Materials, Xiaohua Ji, Terry M. Tritt, Xinbing Zhao, Joe W. Kolis
Solution Chemical Synthesis Of Nanostructured Thermoelectric Materials, Xiaohua Ji, Terry M. Tritt, Xinbing Zhao, Joe W. Kolis
Journal of the South Carolina Academy of Science
No abstract provided.
Phonon Scattering Effects On Thermal Conductivity Of Tinisn-Based Half-Heusler Alloys, S. Bhattacharya, T. M. Tritt, M. J. Skove, M. Russell, S. J. Poon, V. Ponnambalam, Y. Xia, N. Thadhani
Phonon Scattering Effects On Thermal Conductivity Of Tinisn-Based Half-Heusler Alloys, S. Bhattacharya, T. M. Tritt, M. J. Skove, M. Russell, S. J. Poon, V. Ponnambalam, Y. Xia, N. Thadhani
Journal of the South Carolina Academy of Science
No abstract provided.
Chiral Recognition Of Amino Acids By Use Of A Fluorescent Resorcinarene, Gerald I. Richard, Hadi M. Marwani, Shan Jiang, Sayo O. Fakayode, Mark Lowry, Robert M. Strongin, Isiah M. Warner
Chiral Recognition Of Amino Acids By Use Of A Fluorescent Resorcinarene, Gerald I. Richard, Hadi M. Marwani, Shan Jiang, Sayo O. Fakayode, Mark Lowry, Robert M. Strongin, Isiah M. Warner
Chemistry Faculty Publications and Presentations
The spectroscopic properties of a chiral boronic acid based resorcinarene macrocycle employed for chiral analysis were investigated. Specifically, the emission and excitation characteristics of tetraarylboronate resorcinarene macrocycle (TBRM) and its quantum yield were evaluated. The chiral selector TBRM was investigated as a chiral reagent for the enantiomeric discrimination of amino acids using steady-state fluorescence spectroscopy. Chiral recognition of amino acids in the presence of the macrocycle was based on diastereomeric complexes. Results demonstrated that TBRM had better chiral discrimination ability for lysine as compared to the other amino acids. Partial least squares regression modeling (PLS-1) of spectral data for macrocycle-lysine …
Adsorption Studies Of Cytochrome C On A Silica Nanoparticle Surface, Carrie Ann Hedge
Adsorption Studies Of Cytochrome C On A Silica Nanoparticle Surface, Carrie Ann Hedge
Undergraduate Honors Thesis Collection
This honors thesis investigated the conformational changes in cytochrome c when it is adsorbed to silica nanoparticle surfaces before denaturant as well as when it is exposed to denaturant and then allowed to adsorb to silica nanoparticles.
Absorption Spectral Slopes And Slope Ratios As Indicators Of Molecular Weight, Source, And Photobleaching Of Chromophoric Dissolved Organic Matter, John R. Helms, Aron Stubbins, Jason D. Ritchie, Elizabeth C. Minor, David J. Kieber, Kenneth Mopper
Absorption Spectral Slopes And Slope Ratios As Indicators Of Molecular Weight, Source, And Photobleaching Of Chromophoric Dissolved Organic Matter, John R. Helms, Aron Stubbins, Jason D. Ritchie, Elizabeth C. Minor, David J. Kieber, Kenneth Mopper
Chemistry & Biochemistry Faculty Publications
A new approach for parameterizing dissolved organic matter ( DOM) ultraviolet-visible absorption spectra is presented. Two distinct spectral slope regions ( 275-295 nm and 350-400 nm) within log-transformed absorption spectra were used to compare DOM from contrasting water types, ranging from wetlands (Great Dismal Swamp and Suwannee River) to photobleached oceanic water ( Atlantic Ocean). On the basis of DOM size-fractionation studies ( ultrafiltration and gel filtration chromatography), the slope of the 275-295- nm region and the ratio of these slopes (SR; 275-295- nm slope : 350-400- nm slope) were related to DOM molecular weight ( MW) and …
Effects, Uptake, And Fate Of 2,4,6-Trinitrotoluene Aged In Soil In Plants And Worms, Elly Ph Best, Henry E. Tatem, Kaaren N. Geter, Melissa L. Wells, Brian K. Lane
Effects, Uptake, And Fate Of 2,4,6-Trinitrotoluene Aged In Soil In Plants And Worms, Elly Ph Best, Henry E. Tatem, Kaaren N. Geter, Melissa L. Wells, Brian K. Lane
United States Army Corps of Engineers, Omaha District
The present study was aimed at providing data to be used at predicting exposure-based effects of 2,4,6-trinitrotoluene (TNT) aged in soil on endpoint organisms representing two trophic levels. These data can be used to define criteria or reference values for environmental management and conducting specific risk assessment. Long-term exposure tests were conducted to evaluate sublethal toxicity and uptake of aged soil-based explosives, with TNT as the main contaminant. In these tests, plants were exposed for 55 d, and biomass and explosives residues were determined. Worms were exposed for 28 and 42 d, and biomass, number, and tissue residues were determined. …
An Embarrassment Of Riches: The Enzymology Of Rna Modification, Dirk Iwata-Reuyl
An Embarrassment Of Riches: The Enzymology Of Rna Modification, Dirk Iwata-Reuyl
Chemistry Faculty Publications and Presentations
The maturation of transfer RNA (tRNA) involves extensive chemical modification of the constituent nucleosides and results in the introduction of significant chemical diversity to tRNA. Many of the pathways to these modified nucleosides are characterized by chemically complex transformations, some of which are unprecedented in other areas of biology. To illustrate the scope of the field, recent progress in understanding the enzymology leading to the formation of two distinct classes of modified nucleosides, the thiouridines and queuosine, a 7-deazaguanosine, is reviewed. In particular, recent data validating the involvement of several proposed intermediates in the formation of thiouridines are discussed, including …