DOE Office of Scientific and Technical Information (OSTI.GOV)
Mohan, Sepuru K.; Rani, Sandhya G.; Kumar, Sriramoju M.
2009-03-13
Fibroblast growth factors (FGFs) are key regulators of cell proliferation, differentiation, tumor-induced angiogenesis and migration. FGFs are essential for early embryonic development, organ formation and angiogenesis. They play important roles in tumor formation, inflammation, wound healing and restenosis. The biological effects of FGFs are mediated through the activation of the four transmembrane phosphotyrosine kinase receptors (FGFRs) in the presence of heparin sulfate proteoglycans (HSPGs) and therefore require the release of FGFs into the extracellular space. However, FGF-1 lacks the signal peptide required for the releasing of these proteins through the classical endoplasmic reticulum (ER)-Golgi secretary pathway. Maciag et al. demonstratedmore » that FGF-1 is exported through a non-classical release pathway involving the formation of a specific multiprotein complex [M. Landriscina, R. Soldi, C. Bagala, I. Micucci, S. Bellum, F. Tarantini, I. Prudovsky, T. Maciag, S100A13 participates in the release of fibroblast growth factor 1 in response to heat shock in vitro, J. Biol. Chem. 276 (2001) 22544-22552; C.M. Carreira, T.M. LaVallee, F. Tarantini, A. Jackson, J.T. Lathrop, B. Hampton, W.H. Burgess, T. Maciag, S100A13 is involved in the regulation of fibroblast growth factor-1 and p40 synaptotagmin-1 release in vitro, J. Biol. Chem. 273 (1998) 22224-22231; T.M. LaValle, F. Tarantini, S. Gamble, C.M. Carreira, A. Jackson, T. Maciag, Synaptotagmin-1 is required for fibroblast growth factor-1 release, J. Biol. Chem. 273 (1998) 22217-22223; C. Bagala, V. Kolev, A. Mandinova, R. Soldi, C. Mouta, I. Graziani, I, Prudovsky, T. Maciag, The alternative translation of synaptotagmin 1 mediates the non-classical release of FGF1, Biochem. Biophys. Res. Commun. 310 (2003) 1041-1047]. The protein constituents of this complex include FGF-1, S100A13 (a Ca{sup 2+}-binding protein), and the p40 form of synaptotagmin 1 (Syt1). To understand the molecular events in the FGF-1 releasing pathway, we have studied the interactions of S100A13 with C2A by {sup 1}H-{sup 15}N HSQC titration and 3D-filtered NOESY experiments. We characterized the binary complex structure of S100A13-C2A by using a variety of multi-dimensional NMR experiments. This complex acts as a template for FGF-1 dimerization and multiprotein complex formation.« less
Interaction of S100A13 with C2 domain of receptor for advanced glycation end products (RAGE).
Rani, Sandhya G; Sepuru, Krishna Mohan; Yu, Chin
2014-09-01
S100A13 is involved in several key biological functions like angiogenesis, tumor formation and cell apoptosis. It is a homodimeric protein that belongs to the S100 protein family. S100A13 is co-expressed with acidic fibroblast growth factor (FGF1) and interleukin-1α which are key angiogenesis inducers. The S100 proteins have been shown to be involved in several cellular functions such as calcium homeostasis, cell growth and differentiation dynamic of cytoskeleton. Its biological functions are mainly mediated through the receptor for advanced glycation end products (RAGE) signaling. RAGE is involved in inflammatory processes and is associated with diabetic complications, tumor outgrowth, and neurodegenerative disorders. RAGE induces cellular signaling upon binding of different ligands, such as S100 proteins, glycated proteins, and HMGB1. RAGE signaling is complex, and it depends on the cell type and concentration of the ligand. Molecular level interactions of RAGE and S100 proteins are useful to understand the RAGE signaling diversity. In this report we focus on the molecular level interactions of S100A13 and RAGE C2 domain. The binding between RAGE C2 and S100A13 is moderately strong (Kd~1.3μM). We have solved the solution structure of the S100A13-RAGE C2 complex and pronounce the interface regions in S100A13-RAGE C2 complex which are helpful for drug development of RAGE induced diseases. Copyright © 2014 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Castellino, S.; Leo, G.C.; Sammons, R.D.
1989-05-02
The herbicidal dead-end ternary complex (E{sup S3P}{sub Glyph}) of glyphosate (N-(phosphonomethyl)glycine) with 5-enolpyruvoylshikimate-3-phosphate synthase (EPSPS) and the substrate shikimate 3-phosphate (S3P) has been characterized by {sup 31}P, {sup 15}N, and {sup 13}C NMR. The NMR spectra of EPSPS-bound glyphosate show unique chemical shifts ({delta}) for each of the three nuclei. By {sup 31}P NMR, glyphosate in the dead-end complex is a distinct species 3.5 ppm downfield from free glyphosate. The {sup 13}C signal of glyphosate in the dead-end complex is shifted 4 ppm downfield from that of free glyphosate. The {sup 15}N signal for glyphosate (99%) in the dead-end complexmore » is 5 ppm further downfield than that of any free zwitterionic species and 10 ppm downfield from that of the average free species at pH 10.1. The structures of each ionic state of glyphosate are modeled with force field calculations by using MacroModel. A correlation is made for the {sup 31}P {delta} and the C-P-O bond angle, and the {sup 13}C and {sup 15}N {delta} values are postulated to be related to C-C-O and C-N-C bond angles, respectively. The downfield {sup 31}P chemical shift perturbation for S3P in the EPSPS binary complex is consistent with ionization of the 3-phosphate of S3P upon binding. Comparison with the S3P {sup 31}P {delta} vs pH titration curve specifies predominantly the dianion of the 3-phosphate in the E{sup S3P} binary complex, while the E{sup S3P}{sub Glyph} complex indicates net protonation at the 3-phosphate. Chemical shift perturbations of this latter type may be explained by changes in the O-P-O bond angle.« less
MESA models for the evolutionary status of the epsilon Aurigae disk-eclipsed binary system
NASA Astrophysics Data System (ADS)
Stencel, Robert E.; Gibson, Justus
2018-06-01
The brightest member of the class of disk-eclipsed binary stars is the Algol-like long-period binary, epsilon Aurigae (HD 31964, F0Iap + disk, http://adsabs.harvard.edu/abs/2016SPIE.9907E..17S ). Using MESA (Modules for Experiments in Stellar Astrophysics, version 9575), we have made an evaluation of its evolutionary state. We sought to satisfy several observational constraints, including: (1) requiring evolutionary tracks to pass close to the current temperature and luminosity of the primary star; (2) obtaining a period near the observed value of 27.1 years; (3) matching a mass function of 3.0; (4) concurrent Roche lobe overflow and mass transfer; (5) an isotopic ratio 12C / 13C = 5 and, (6) matching the interferometrically determined angular diameter. A MESA model starting with binary masses of 9.85 + 4.5 solar masses, with a 100 day initial period, produces a 1.2 + 10.6 solar masses result having a 547 day period, plus a single digit 12C / 13C ratio. These values were reached near an age of 20 Myr, when the donor star comes close to the observed luminosity and temperature for epsilon Aurigae A, as a post-RGB/pre-AGB star. Contemporaneously, the accretor then appears as an upper main sequence, early B-type star. This benchmark model can provide a basis for further exploration of this interacting binary, and other long period binary stars. This report has been submitted to MNRAS, along with a parallel investigation of mass transfer stream and disk sub-structure. The authors are grateful to the estate of William Herschel Womble for the support of astronomy at the University of Denver.
Electrical Resistivity of Ten Selected Binary Alloy Systems.
1981-04-01
100 m 2 L q2 2 J 4m v 2 1 ......... 13 I Here e , m, and v are the electronic charge, mass, and velocity, q is the screening parameter, and I is the...potentiometer method E Eddy current decay method wpik* -7 25 P Van der Pauw method R Rotating magnetic field method V Voltmeter and ammeter direct...r:~ 0; tz 0 hi~~ 0*~ . 0 . 6 0 M 0 0 % -0 0 e o C M -" I- I n WT 8 L a .44 44 -44 4 %. -~~ 0 0 0 0 U0. ii S 4. 0c .2 s , Q t 04 INN ) nW V W 33
MESA models of the evolutionary state of the interacting binary epsilon Aurigae
NASA Astrophysics Data System (ADS)
Gibson, Justus L.; Stencel, Robert E.
2018-06-01
Using MESA code (Modules for Experiments in Stellar Astrophysics, version 9575), an evaluation was made of the evolutionary state of the epsilon Aurigae binary system (HD 31964, F0Iap + disc). We sought to satisfy several observational constraints: (1) requiring evolutionary tracks to pass close to the current temperature and luminosity of the primary star; (2) obtaining a period near the observed value of 27.1 years; (3) matching a mass function of 3.0; (4) concurrent Roche lobe overflow and mass transfer; (5) an isotopic ratio 12C/13C = 5 and, (6) matching the interferometrically determined angular diameter. A MESA model starting with binary masses of 9.85 + 4.5 M⊙, with a 100 d initial period, produces a 1.2 + 10.6 M⊙ result having a 547 d period, and a single digit 12C/13C ratio. These values were reached near an age of 20 Myr, when the donor star comes close to the observed luminosity and temperature for epsilon Aurigae A, as a post-RGB/pre-AGB star. Contemporaneously, the accretor then appears as an upper main-sequence, early B-type star. This benchmark model can provide a basis for further exploration of this interacting binary, and other long-period binary stars.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cho, Ching Chang, E-mail: ccjwo@yahoo.com.tw; Chou, Ruey Hwang, E-mail: rhchou@mail.cmu.edu.tw; Yu, Chin, E-mail: cyu.nthu@gmail.com
The human S100 protein family contains small, dimeric and acidic proteins that contain two EF-hand motifs and bind calcium. When S100A5 binds calcium, its conformation changes and promotes interaction with the target protein. The extracellular domain of RAGE (Receptor of Advanced Glycation End products) contain three domains: C1, C2 and V. The RAGE V domain is the target protein of S100A5 that promotes cell survival, growth and differentiation by activating several signaling pathways. Pentamidine is an apoptotic and antiparasitic drug that is used to treat or prevent pneumonia. Here, we found that pentamidine interacts with S100A5 using HSQC titration. Wemore » elucidated the interactions of S100A5 with RAGE V domain and pentamidine using fluorescence and NMR spectroscopy. We generated two binary models—the S100A5-RAGE V domain and S100A5-Pentamidine complex—and then observed that the pentamidine and RAGE V domain share a similar binding region in mS100A5. We also used the WST-1 assay to investigate the bioactivity of S100A5, RAGE V domain and pentamidine. These results indicated that pentamidine blocks the binding between S100A5 and RAGE V domain. This finding is useful for the development of new anti-proliferation drugs. - Highlights: • The interaction between mS100A5–RAGE V was investigated by fluorescence spectroscopy. • The interfacial residues on mS100A5–RAGE V and mS100A5–pentamidine contact surface were mapped by {sup 1}H-{sup 15}N HSQC experiments. • mS100A5–RAGE V and mS100A5–pentamidine complex models were generated from NMR restraints using HADDOCK program. • The bioactivity of the mS100A5–RAGE V and mS100A5–pentamidine complex was studied using WST-1 assay.« less
Espinoza-Herrera, Shirly J; Gaur, Vineet; Suo, Zucai; Carey, Paul R
2013-07-23
Y-Family DNA polymerases are known to bypass DNA lesions in vitro and in vivo. Sulfolobus solfataricus DNA polymerase (Dpo4) was chosen as a model Y-family enzyme for investigating the mechanism of DNA synthesis in single crystals. Crystals of Dpo4 in complexes with DNA (the binary complex) in the presence or absence of an incoming nucleotide were analyzed by Raman microscopy. (13)C- and (15)N-labeled d*CTP, or unlabeled dCTP, were soaked into the binary crystals with G as the templating base. In the presence of the catalytic metal ions, Mg(2+) and Mn(2+), nucleotide incorporation was detected by the disappearance of the triphosphate band of dCTP and the retention of *C modes in the crystal following soaking out of noncovalently bound C(or *C)TP. The addition of the second coded base, thymine, was observed by adding cognate dTTP to the crystal following a single d*CTP addition. Adding these two bases caused visible damage to the crystal that was possibly caused by protein and/or DNA conformational change within the crystal. When d*CTP is soaked into the Dpo4 crystal in the absence of Mn(2+) or Mg(2+), the primer extension reaction did not occur; instead, a ternary protein·template·d*CTP complex was formed. In the Raman difference spectra of both binary and ternary complexes, in addition to the modes of d(*C)CTP, features caused by ring modes from the template/primer bases being perturbed and from the DNA backbone appear, as well as features from perturbed peptide and amino acid side chain modes. These effects are more pronounced in the ternary complex than in the binary complex. Using standardized Raman intensities followed as a function of time, the C(*C)TP population in the crystal was maximal at ∼20 min. These remained unchanged in the ternary complex but declined in the binary complexes as chain incorporation occurred.
HEPATOTOXIC EVALUATION OF THE BINARY INTERACTIONS OF BROMODICHLOROMETHANE (BDCM) WITH CHLOROFORM (CHC13), CHLORODIBROMOMETHANE (CDBM) AND BROMOFORM (CHBr3). Y M Se'', C Gennings2, A McDonald', L K Teuschler3, A Hamm2and J E Simmons .'NHEERL, ORD, U.S. EPA, RTP, NC; 2MCV, VCU, Ric...
Ohyama, Ayumu; Higashi, Taishi; Motoyama, Keiichi; Arima, Hidetoshi
2017-06-01
We previously developed a tumor-selective siRNA carrier by preparing polyamidoamine dendrimer (generation 4, G4) conjugates with α-cyclodextrin and folate-polyethylene glycol (Fol-PαC (G4)). In the present study, we developed ternary complexes of Fol-PαC (G4)/siRNA with low-molecular-weight-sacrans to achieve more effective siRNA transfer activity. Among the different molecular-weight sacrans, i.e. sacran 100, 1000 and 10,000 (MW 44,889Da, 943,692Da and 1,488,281Da, respectively), sacran 100 significantly increased the cellular uptake and the RNAi effects of Fol-PαC (G4)/siRNA binary complex with negligible cytotoxicity in KB cells (folate receptor-α positive cells). In addition, the ζ-potential and particle size of Fol-PαC (G4)/siRNA complex were decreased by the ternary complexation with sacran 100. Importantly, the in vivo RNAi effect of the ternary complex after the intravenous administration to tumor-bearing BALB/c mice was significantly higher than that of the binary complex. In conclusion, Fol-PαC (G4)/siRNA/sacran 100 ternary complex has a potential as a novel tumor-selective siRNA delivery system. Copyright © 2017 Elsevier B.V. All rights reserved.
Intermolecular forces in acetonitrile + ethanol binary liquid mixtures
NASA Astrophysics Data System (ADS)
Elangovan, A.; Shanmugam, R.; Arivazhagan, G.; Mahendraprabu, A.; Karthick, N. K.
2015-10-01
FTIR spectral measurements have been carried out on the binary mixtures of acetonitrile with ethanol at 1:0 (acetonitrile:ethanol), 1:1, 1:2, 1:3 and 0:1 at room temperature. DFT and isosurface calculations have been performed. The acetonitrile + ethanol binary mixtures consist of 1:1, 1:2, 1:3 and 1:4 complexes formed through both the red and blue shifting H-bonds. Inter as well as intra molecular forces are found to exist in 1:3 and 1:4 complexes.
Tokuda, K; Okamoto, K; Konno, T
2000-01-24
The reaction of an S-bridged Co2(III)Ag3(I) pentanuclear complex, [Ag3[Co(aet)3]2][BF4]3 (aet = NH2CH2CH2S-), with paraformaldehyde in basic acetonitrile, followed by adding aqueous ammonia, produced an aza-capped Co2(III)-Ag3(I) complex, [Ag3[Co(L)]2]3+ ([1]3+) (L = N(CH2NHCH2CH2S-)3). The crystal structure of [1]3+ was determined by X-ray crystallography. [1][PF6]3 x H2O, empirical formula C18H44Ag3Co2F18N8OP3S6, crystallizes in the tetragonal space group 142m with a = 13.012(1) A, c = 24.707(2) A, and Z = 4. In [1]3+ the two aza-capped [Co(L)] units are linked by three Ag(I) atoms, such that the two Co(III) atoms are encapsulated in a macrobicyclic metallocage, [Ag3(I)(L)2]3-. [1]3+ was converted to an aza-capped Co4(III)Zn4(II) octanuclear complex, [Zn4O[Co(L)]4]6+ ([2]6+), by reaction with I- in the presence of Zn2+ and ZnO in water. The crystal structure of [2]6+ was also determined by X-ray crystallography. [2][PF6]6 x 8H2O, empirical formula C36H100Co4F36N16O9P6S12Zn4, crystallizes in the monoclinic space group P2(1/n) with a = 14.33(7) A, b = 25.67(10) A, c = 24.83(6) A, beta = 101.3(3) degrees , and Z = 4. In [2]6+ each of four [Co(L)] units is bound to each trigonal Zn3(II) face of the tetrahedral [Zn4(II)O]6+ core, such that each Co(III) atom is encapsulated in a macrobicyclic [Zn4(II)O(L)] fragment. Treatment of [2]6+ with a basic aqueous solution resulted in a cleavage of the Zn-S bonds to produce an aza-capped Co(III) mononuclear complex, [Co(L)] ([3]), from which [1]3+ is readily reproduced by the reaction with Ag+ in water. All the reactions were found to proceed with retention of the absolute configuration (delta or lambda) of the Co(III) chiral centers; deltadelta-[1]3+, deltadeltadeltadelta-[2]6+, and A-[3] were derived from deltadelta-[Ag3[Co(aet)3]2]3+. The contributions to circular dichroism (CD) from the triple helicity in [1]3+, besides from the asymmetric N and S donor atoms and the Co(III) chiral centers in [1]3+ and [2]6+, were estimated by comparing the CD spectra of deltadelta-[1]3+, deltadeltadeltadelta-[2]6+, and delta-[3].
NASA Astrophysics Data System (ADS)
Jørgensen, J. K.; van der Wiel, M. H. D.; Coutens, A.; Lykke, J. M.; Müller, H. S. P.; van Dishoeck, E. F.; Calcutt, H.; Bjerkeli, P.; Bourke, T. L.; Drozdovskaya, M. N.; Favre, C.; Fayolle, E. C.; Garrod, R. T.; Jacobsen, S. K.; Öberg, K. I.; Persson, M. V.; Wampfler, S. F.
2016-11-01
Context. The inner regions of the envelopes surrounding young protostars are characterized by a complex chemistry, with prebiotic molecules present on the scales where protoplanetary disks eventually may form. The Atacama Large Millimeter/submillimeter Array (ALMA) provides an unprecedented view of these regions zooming in on solar system scales of nearby protostars and mapping the emission from rare species. Aims: The goal is to introduce a systematic survey, the Protostellar Interferometric Line Survey (PILS), of the chemical complexity of one of the nearby astrochemical templates, the Class 0 protostellar binary IRAS 16293-2422, using ALMA in order to understand the origin of the complex molecules formed in its vicinity. In addition to presenting the overall survey, the analysis in this paper focuses on new results for the prebiotic molecule glycolaldehyde, its isomers, and rarer isotopologues and other related molecules. Methods: An unbiased spectral survey of IRAS 16293-2422 covering the full frequency range from 329 to 363 GHz (0.8 mm) has been obtained with ALMA, in addition to a few targeted observations at 3.0 and 1.3 mm. The data consist of full maps of the protostellar binary system with an angular resolution of 0.5'' (60 AU diameter), a spectral resolution of 0.2 km s-1, and a sensitivity of 4-5 mJy beam-1 km s-1, which is approximately two orders of magnitude better than any previous studies. Results: More than 10 000 features are detected toward one component in the protostellar binary, corresponding to an average line density of approximately one line per 3 km s-1. Glycolaldehyde; its isomers, methyl formate and acetic acid; and its reduced alcohol, ethylene glycol, are clearly detected and their emission well-modeled with an excitation temperature of 300 K. For ethylene glycol both lowest state conformers, aGg' and gGg', are detected, the latter for the first time in the interstellar medium (ISM). The abundance of glycolaldehyde is comparable to or slightly larger than that of ethylene glycol. In comparison to the Galactic Center these two species are over-abundant relative to methanol, possibly an indication of formation of the species at low temperatures in CO-rich ices during the infall of the material toward the central protostar. Both 13C and the deuterated isotopologues of glycolaldehyde are detected, also for the first time ever in the ISM. For the deuterated species, a D/H ratio of ≈5% is found with no differences between the deuteration in the different functional groups of glycolaldehyde, in contrast to previous estimates for methanol and recent suggestions of significant equilibration between water and -OH functional groups at high temperatures. Measurements of the 13C-species lead to a 12C:13C ratio of ≈30, lower than the typical ISM value. This low ratio may reflect an enhancement of 13CO in the ice due to either ion-molecule reactions in the gas before freeze-out or to differences in the temperatures where 12CO and 13CO ices sublimate. Conclusions: The results reinforce the importance of low-temperature grain surface chemistry for the formation of prebiotic molecules seen here in the gas after sublimation of the entire ice mantle. Systematic surveys of the molecules thought to be chemically related, as well as the accurate measurements of their isotopic composition, hold strong promise for understanding the origin of prebiotic molecules in the earliest stages of young stars.
Bottenus, Brienne N; Kan, Para; Jenkins, Tyler; Ballard, Beau; Rold, Tammy L; Barnes, Charles; Cutler, Cathy; Hoffman, Timothy J; Green, Mark A; Jurisson, Silvia S
2010-01-01
A variety of (bis)thiosemicarbazone-based ligand systems have been investigated as chelating agents for Au(III) complexes with potential radiotherapeutic applications. Ligand systems containing an ethyl, propyl or butyl backbone between the two imine N donors have been synthesized to evaluate chelate ring size effects on the resultant Au(III) complex stability at the macroscopic and radiotracer levels. The Au(III) complexes were synthesized and characterized by NMR, electrospray ionization mass spectra, elemental analysis and X-ray crystallography. The (198)Au complexes were evaluated in vitro at the tracer level for stability in phosphate-buffered saline at pH 7.4 and 37 degrees C. One of these complexes [(198)Au(3,4-HxTSE)] showed high in vitro stability and was further evaluated in vivo in normal mice. [Au(ATSM)]AuCl(4).2CH(3)OH, (ATSM=diacetyl-bis(N(4)-methylthiosemicarbazone)) H(14)C(8)N(6)O(2)S(2)Cl(4)Au(2).2CH(3)OH, crystallized from methanol in the monoclinic space group P21/n with a=14.7293(13) A, b=7.7432(7) A, c=20.4363(18) A, beta=100.140(2) degrees, V=2294.4 (4) A(3), Z=4; [Au(3,4-HxTSE)]Cl.CH(3)CH(2)OH/AuCl(2), (3,4-HxTSE=3,4-hexanedione-bis(N(4)-ethylthiosemicarbazone)) H(26)C(13.6)N(6)O(0.8)S(2)Cl(1.2)Au(1.2), crystallized from ethanol in the monoclinic space group P21/c with a=10.1990(10) A, b=13.8833(14) A, c=15.1752(15) A, beta=99.353(2) degrees , V=2120.2 (4) A(3), Z=4. These studies revealed poor stability of the [(198)Au][Au(3,4-HxTSE)](+) complex; however, crystal structure data suggest potential alterations to the ligand backbone may increase stability. Copyright 2010 Elsevier Inc. All rights reserved.
CdS/C60 binary nanocomposite films prepared via phase transition of PS-b-P2VP block copolymer.
Lee, Jung-Pil; Koh, Haeng-Deog; Shin, Won-Jeong; Kang, Nam-Goo; Park, Soojin; Lee, Jae-Suk
2014-03-01
We demonstrate the well-defined control of phase transition of a polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) block copolymer from spherical micelles to lamellar structures, in which CdS and C60 nanoparticles (NPs) are selectively positioned at the P2VP domains. The CdS NPs are in situ synthesized using PS-b-P2VP block copolymer templates that are self-assembled in PS-selective solvents. The CdS-PS-b-P2VP micellar structures are transformed to lamellar phase by adjusting a solvent selectivity for both blocks. In addition, a binary system of CdS/C60 embedded in PS-b-P2VP lamellar structures (CdS/C60-PS-b-P2VP) is fabricated by embedding C60 molecules into P2VP domain though charge-transfer complexation between pyridine units of PS-b-P2VP and C60 molecules. The CdS/C60-PS-b-P2VP nanostructured films are characterized by transmission electron microscopy (TEM) and UV-Vis spectrometer. Copyright © 2013 Elsevier Inc. All rights reserved.
Dielectric properties of binary mixtures of methyl iso butyl ketone and amino silicone oil
NASA Astrophysics Data System (ADS)
Shah, K. N.; Rana, V. A.; Trivedi, C. M.; Vankar, H. P.
2017-05-01
Dielectric permittivity ɛ*(ω) = ɛ' - jɛ″ of the binary mixtures of the methyl iso butyl ketone and amino silicone oil in the frequency range 100 Hz to 2 MHz were measured using precision LCR meter at 305.15 K. Relative complex permittivity spectra in the frequency range 100 Hz to 2 MHz, of the mixture solutions of varying concentrations is reported. Determined values of the permittivity at optical frequency of all the samples are also reported. The dielectric parameters are used to gain information about the effect of concentration variation of components of the mixtures on the dielectric properties. It also provides the information about electrode polarization phenomena taking place under the low frequency A.C. electric field.
Williams, Linda A.; Guo, Neng; Motta, Alessandro; Delferro, Massimiliano; Fragalà, Ignazio L.; Miller, Jeffrey T.; Marks, Tobin J.
2013-01-01
Structural characterization of the catalytically significant sites on solid catalyst surfaces is frequently tenuous because their fraction, among all sites, typically is quite low. Here we report the combined application of solid-state 13C-cross-polarization magic angle spinning nuclear magnetic resonance (13C-CPMAS-NMR) spectroscopy, density functional theory (DFT), and Zr X-ray absorption spectroscopy (XAS) to characterize the adsorption products and surface chemistry of the precatalysts (η5-C5H5)2ZrR2 (R = H, CH3) and [η5-C5(CH3)5]Zr(CH3)3 adsorbed on Brønsted superacidic sulfated alumina (AlS). The latter complex is exceptionally active for benzene hydrogenation, with ∼100% of the Zr sites catalytically significant as determined by kinetic poisoning experiments. The 13C-CPMAS-NMR, DFT, and XAS data indicate formation of organozirconium cations having a largely electrostatic [η5-C5(CH3)5]Zr(CH3)2+···AlS− interaction with greatly elongated Zr···OAlS distances of ∼2.35(2) Å. The catalytic benzene hydrogenation cycle is stepwise understandable by DFT, and proceeds via turnover-limiting H2 delivery to surface [η5-C5(CH3)5]ZrH2(benzene)+···AlS− species, observable by solid-state NMR and XAS. PMID:23269836
Sun, Enwei; Cao, Wenwu; Han, Pengdi
2011-08-01
The frequency dispersion of ultrasonic velocity and attenuation in [001](c)-poled 0.24Pb(in(1/2)Nb(1/2))O(3)-0.45Pb(Mg(1/3)Nb(2/3))o(3)-0.31PbTio(3) (PIN-0.45PMN-0.31PT) ternary single crystal were measured by ultrasonic spectroscopy from 25 to 100 MHz for the longitudinal wave. It was found that the velocity has a linear relationship with the frequency f, but the attenuation has a quadratic relation with f. The attenuation and frequency dispersion of the ternary system are lower than that of the (1-x)Pb(Mg(1/3)Nb(2/3))O(3)-xPbTiO(3) (PMN-PT) binary system and the coercive field also increased by a factor of 2.5, hence, the ternary single system is superior to the corresponding binary single-crystal system for high-frequency and high-power transducer applications.
Free Energy Calculations of Crystalline Hard Sphere Complexes Using Density Functional Theory
Gunawardana, K. G.S.H.; Song, Xueyu
2014-12-22
Recently developed fundamental measure density functional theory (FMT) is used to study binary hard sphere (HS) complexes in crystalline phases. By comparing the excess free energy, pressure and phase diagram, we show that the fundamental measure functional yields good agreements to the available simulation results of AB, AB 2 and AB 13 crystals. Additionally, we use this functional to study the HS models of five binary crystals, Cu 5Zr(C15 b), Cu 51Zr 14(β), Cu 10Zr 7(φ), CuZr(B2) and CuZr 2 (C11 b), which are observed in the Cu-Zr system. The FMT functional gives well behaved minimum for most of themore » hard sphere crystal complexes in the two dimensional Gaussian space, namely a crystalline phase. However, the current version of FMT functional (white Bear) fails to give a stable minimum for the structure Cu 10Zr 7(φ). We argue that the observed solid phases for the HS models of the Cu-Zr system are true thermodynamic stable phases and can be used as a reference system in perturbation calculations.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takakuwa, Shigehisa; Kiyokane, Kazuhiro; Saigo, Kazuya
2015-12-01
We performed mapping observations of the Class I protostellar binary system L1551 NE in the C{sup 18}O (J = 3–2), {sup 13}CO (J = 3–2), CS (J = 7–6), and SO (J{sub N} = 7{sub 8}–6{sub 7}) lines with the Atacama Submillimeter Telescope Experiment (ASTE). The ASTE C{sup 18}O data were combined with our previous SMA C{sup 18}O data, which show a r ∼ 300 AU scale Keplerian disk around the protostellar binary system. The C{sup 18}O maps show a ∼20,000 AU scale protostellar envelope surrounding the central Keplerian circumbinary disk. The envelope exhibits a northeast (blue) to southwest (red) velocity gradient along the minor axis, which can be interpreted as amore » dispersing gas motion with an outward velocity of 0.3 km s{sup −1}, while no rotational motion in the envelope is seen. In addition to the envelope, two ≲4000 AU scale, high-velocity (≳1.3 km s{sup −1}) redshifted {sup 13}CO and CS emission components are found ∼40″ southwest and ∼20″ west of the protostellar binary. These redshifted components are most likely outflow components driven from the neighboring protostellar source L1551 IRS 5, and are colliding with the envelope in L1551 NE. The net momentum, kinetic, and internal energies of the L1551 IRS 5 outflow components are comparable to those of the L1551 NE envelope, and the interactions between the outflows and the envelope are likely to cause the dissipation of the envelope and thus suppression of further growth of the mass and mass ratio of the central protostellar binary in L1551 NE.« less
Garnero, Claudia; Chattah, Ana Karina; Aloisio, Carolina; Fabietti, Luis; Longhi, Marcela
2018-05-10
Norfloxacin, an antibiotic that exists in different solid forms, has very unfavorable properties in terms of solubility and stability. Binary complexes of norfloxacin, in the solid form C, and β-cyclodextrin were procured by the kneading method and physical mixture. Their effect on the solubility, the dissolution rate, and the chemical and physical stability of norfloxacin was evaluated. To perform stability studies, the solid samples were stored under accelerated storage conditions, for a period of 6 months. Physical stability was monitored through powder X-ray diffraction, high-resolution 13 C solid-state nuclear magnetic resonance, and scanning electron microscopy. The results showed evidence that the kneaded complex increased and modulated the dissolution rate of norfloxacin C. Furthermore, it was demonstrated that the photochemical stability was increased in the complex, without affecting its physical stability. The results point to the conclusion that the new kneading complex of norfloxacin constitutes an alternative tool to formulate a potential oral drug delivery system with improve oral bioavailability.
Blocking the interaction between S100A9 protein and RAGE V domain using S100A12 protein.
Katte, Revansiddha; Yu, Chin
2018-01-01
The proteins S100A9 and S100A12 are associated with the human S100 calcium-binding protein family. These proteins promote interaction with target proteins and alter their conformation when they bind to calcium ions in EF-hand motifs. The V domain of RAGE (Receptor for Advanced Glycation End products) is crucial for S100A9 binding. The binding of RAGE with S100 family proteins aids in cell proliferation. In this report, we demonstrate that S100A12 protein hinders the binding of S100A9 with the RAGE V-domain. We used fluorescence and NMR spectroscopy to analyze the interaction of S100A9 with S100A12. The binary complex models of S100A9-S100A12 were developed using data obtained from 1H-15N HSQC NMR titrations and the HADDOCK program. We overlaid the complex models of S100A9-S100A12 with the same orientation of S100A9 and the RAGE V-domain. This complex showed that S100A12 protein blocks the interaction between S100A9 and the RAGE V-domain. It means S100A12 may be used as an antagonist for S100A9. The results could be favorable for developing anti-cancer drugs based on S100 family proteins.
NASA Astrophysics Data System (ADS)
Habibi, N.; Rounaghi, G. H.; Mohajeri, M.
2012-12-01
The complexation reaction of macrocyclic ligand (4'-nitrobenzo-15C5) with Y3+ cation was studied in acetonitrile-methanol (AN-MeOH), acetonitrile-ethanol (AN-EtOH), acetonitrile-dimethylformamide (AN-DMF) and ethylacetate-methanol (EtOAc-MeOH) binary mixtures at different temperatures using conductometry method. The conductivity data show that in all solvent systems, the stoichiometry of the complex formed between 4'-nitrobenzo-15C5 and Y3+ cation is 1: 1 (ML). The stability order of (4'-nitrobenzo-15C5). Y3+ complex in pure non-aqueous solvents at 25°C was found to be: EtOAc > EtOH > AN ≈ DMF > MeOH, and in the case of most compositions of the binary mixed solvents at 25°C it was: AN≈MeOH ≈ AN-EtOH > AN-DMF > EtOAc-MeOH. But the results indicate that the sequence of the stability of the complex in the binary mixed solutions changes with temperature. A non-linear behavior was observed for changes of log K f of (4'-nitrobenzo-15C5 · Y3+) complex versus the composition of the binary mixed solvents, which was explained in terms of solvent-solvent interactions and also the hetero-selective solvation of the species involved in the complexation reaction. The values of thermodynamic parameters (Δ H {c/ℴ} and Δ S {c/ℴ}) for formation of the complex were obtained from temperature dependent of the stability constant using the van't Hoff plots. The results represent that in most cases, the complex is both enthalpy and entropy stabilized and the values and also the sign of thermodynamic parameters are influenced by the nature and composition of the mixed solvents.
Carbon Isotopic Compositions in Carbon Dioxide Measured By Micro-Laser Raman Spectroscopy
NASA Astrophysics Data System (ADS)
Li, J.-J.; Li, R.-X.; Dong, H.; Wang, Zh.-H.; Zhao, B.-S.; Wang, N.; Cheng, J.-H.
2017-05-01
We have prepared a series of 12CO2/13CO2 binary mixtures as standard samples at room temperature. Using microlaser Raman spectroscopy, it was found that the relationship between the 12CO2 mole fractions and the peak area ratios of 12CO2/13CO2 in the Raman spectra of CO2 binary mixtures showed a polynomial correlation. The establishment of the experimental working curve paves the way for estimating the mole fractions of each individual fluid inclusion and determining 13C/12C and δ13C u sing micro-Raman spectroscopy. The Raman spectra of 12CO2 and 13CO2 showed a characteristic peak at 1348 cm-1 with an argon laser at 785 nm, which is perhaps due to the formation of dimers.
Roth, Braden M; Godoy-Ruiz, Raquel; Varney, Kristen M; Rustandi, Richard R; Weber, David J
2016-04-01
Clostridium difficile is a bacterial pathogen and is the most commonly reported source of nosocomial infection in industrialized nations. Symptoms of C. difficile infection (CDI) include antibiotic-associated diarrhea, pseudomembranous colitis, sepsis and death. Over the last decade, rates and severity of hospital infections in North America and Europe have increased dramatically and correlate with the emergence of a hypervirulent strain of C. difficile characterized by the presence of a binary toxin, CDT (C. difficile toxin). The binary toxin consists of an enzymatic component (CDTa) and a cellular binding component (CDTb) that together form the active binary toxin complex. CDTa harbors a pair of structurally similar but functionally distinct domains, an N-terminal domain (residues 1-215; (1-215)CDTa) that interacts with CDTb and a C-terminal domain (residues 216-420; (216-420)CDTa) that harbors the intact ADP-ribosyltransferase (ART) active site. Reported here are the (1)H, (13)C, and (15)N backbone resonance assignments of the 23 kDa, 205 amino acid C-terminal enzymatic domain of CDTa, termed (216-420)CDTa. These NMR resonance assignments for (216-420)CDTa represent the first for a family of ART binary toxins and provide the framework for detailed characterization of the solution-state protein structure determination, dynamic studies of this domain, as well as NMR-based drug discovery efforts.
Ionic conductivity of binary fluorides of potassium and rare earth elements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sorokin, N. I., E-mail: nsorokin1@yandex.ru
2016-01-15
The ionic conductivity s of KYF{sub 4} and K{sub 2}RF{sub 5} single crystals (R = Gd, Ho, Er) and KNdF{sub 4} and K{sub 2}RF{sub 5} ceramic samples (R = Dy, Er) has been studied in the temperature range of 340–500°C. A comparative analysis of the σ values for these objects has been performed. Binary fluorides of potassium and rare earth elements were synthesized by the hydrothermal method (temperature 480°C, pressure 100–150 MPa) in the R{sub 2}O{sub 3}–KF–H{sub 2}O systems. The σ values of tetraf luorides are 3 × 10{sup –5} S/cm (KYF{sub 4} single crystal) and 3 × 10{sup –6}more » S/cm (KNdF{sub 4} ceramics) at 435°C. A K{sub 2}ErF{sub 5} single crystal with σ = 1.2 × 10{sup –4} S/cm at 435°C has the maximum value of ionic conductivity among pentafluorides. The anisotropy of ionic transport was found in K{sub 2}HoF{sub 5} single crystals, σ{sub ∥c}/σ{sub ⊥c} = 2.5, where σ{sub ∥c} and σ{sub ⊥c} are, respectively, the conductivities along the crystallographic c axis and in the perpendicular direction.« less
PAM-Dependent Target DNA Recognition and Cleavage by C2c1 CRISPR-Cas Endonuclease
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Hui; Gao, Pu; Rajashankar, Kanagalaghatta R.
C2c1 is a newly identified guide RNA-mediated type V-B CRISPR-Cas endonuclease that site-specifically targets and cleaves both strands of target DNA. We have determined crystal structures of Alicyclobacillus acidoterrestris C2c1 (AacC2c1) bound to sgRNA as a binary complex and to target DNAs as ternary complexes, thereby capturing catalytically competent conformations of AacC2c1 with both target and non-target DNA strands independently positioned within a single RuvC catalytic pocket. Moreover, C2c1-mediated cleavage results in a staggered seven-nucleotide break of target DNA. crRNA adopts a pre-ordered five-nucleotide A-form seed sequence in the binary complex, with release of an inserted tryptophan, facilitating zippering upmore » of 20-bp guide RNA:target DNA heteroduplex on ternary complex formation. Notably, the PAM-interacting cleft adopts a “locked” conformation on ternary complex formation. Structural comparison of C2c1 ternary complexes with their Cas9 and Cpf1 counterparts highlights the diverse mechanisms adopted by these distinct CRISPR-Cas systems, thereby broadening and enhancing their applicability as genome editing tools.« less
PREDICTING GAIA’S PARALLAX DISTANCE TO THE CYGNUS OB2 ASSOCIATION WITH ECLIPSING BINARIES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiminki, Daniel C.; Kobulnicky, Henry A.; Álvarez, Carlos A. Vargas
2015-10-01
The Cygnus OB2 Association is one of the nearest and largest collections of massive stars in the Galaxy. Situated at the heart of the “Cygnus X” complex of star-forming regions and molecular clouds, its distance has proven elusive owing to the ambiguous nature of kinematic distances along this ℓ ≃ 80° sightline and the heavy, patchy extinction. In an effort to refine the three-dimensional geometry of key Cygnus X constituents, we have measured distances to four eclipsing double-lined OB-type spectroscopic binaries that are probable members of Cyg OB2. We find distances of 1.33 ± 0.17, 1.32 ± 0.07, 1.44 ±more » 0.18, and 1.32 ± 0.13 kpc toward MT91 372, MT91 696, CPR2002 A36, and Schulte 3, respectively. We adopt a weighted average distance of 1.33 ± 0.06 kpc. This agrees well with spectrophotometric estimates for the Association as a whole and with parallax measurements of protostellar masers in the surrounding interstellar clouds, thereby linking the ongoing star formation in these clouds with Cyg OB2. We also identify Schulte 3C (O9.5V), a 4″ visual companion to the 4.75 day binary Schulte 3(A+B), as a previously unrecognized Association member.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Modeste Nguimdo, Romain, E-mail: Romain.Nguimdo@vub.ac.be; Tchitnga, Robert; Woafo, Paul
We numerically investigate the possibility of using a coupling to increase the complexity in simplest chaotic two-component electronic circuits operating at high frequency. We subsequently show that complex behaviors generated in such coupled systems, together with the post-processing are suitable for generating bit-streams which pass all the NIST tests for randomness. The electronic circuit is built up by unidirectionally coupling three two-component (one active and one passive) oscillators in a ring configuration through resistances. It turns out that, with such a coupling, high chaotic signals can be obtained. By extracting points at fixed interval of 10 ns (corresponding to a bitmore » rate of 100 Mb/s) on such chaotic signals, each point being simultaneously converted in 16-bits (or 8-bits), we find that the binary sequence constructed by including the 10(or 2) least significant bits pass statistical tests of randomness, meaning that bit-streams with random properties can be achieved with an overall bit rate up to 10×100 Mb/s =1Gbit/s (or 2×100 Mb/s =200 Megabit/s). Moreover, by varying the bias voltages, we also investigate the parameter range for which more complex signals can be obtained. Besides being simple to implement, the two-component electronic circuit setup is very cheap as compared to optical and electro-optical systems.« less
Rietzler, Barbara; Laus, Gerhard; Kahlenberg, Volker; Schottenberger, Herwig
2015-12-01
The title salt, [Ag(C5H8N2O2)2]PF6, was obtained by deprotonation and metalation of 1,3-di-meth-oxy-imidazolium hexa-fluorido-phosphate using silver(I) oxide in methanol. The C-Ag-C angle in the cation is 178.1 (2)°, and the N-C-N angles are 101.1 (4) and 100.5 (4)°. The meth-oxy groups adopt an anti conformation. In the crystal, anions (A) are sandwiched between cations (C) in a layered arrangement {C…A…C} n stacked along [001]. Within a C…A…C layer, the hexafluoridophosphate anions accept several C-H⋯F hydrogen bonds from the cationic complex.
Development of sputtered CuSbS2 thin films grown by sequential deposition of binary sulfides
NASA Astrophysics Data System (ADS)
Medina-Montes, M. I.; Vieyra-Brito, O.; Mathews, N. R.; Mathew, X.
2018-05-01
In this work, CuSbS2 thin films were developed by annealing binary precursors deposited sequentially by rf magnetron sputtering. The recrystallization process was optimized and the films were extensively characterized using a number of tools such as XRD, Raman, SEM, energy dispersive x-ray spectroscopy, atomic force microscopy, Hall, UV–vis spectroscopy, Ellipsometry, Seebeck, and photoresponse. The influence of annealing temperature on the structure, morphology, elemental composition, optical and electrical properties are reported. Annealing below 350 °C resulted in famatinite (Cu3SbS4) and chalcostibite (CuSbS2) ternaries as well as binary phases. Phase-pure chalcostibite was obtained in the range of 350 °C–375 °C. At 400 °C, although CuSbS2 was predominant, tetrahedrite phase (Cu12Sb4S13) appeared as an additional phase. The elemental composition of the films was slightly sulfur deficient, and the atomic percentages of Cu, Sb and S showed a dependence on annealing temperature. The material properties of the phase-pure CuSbS2 thin films are: optical band gap in the range of 1.5–1.62 eV, absorption coefficient close to 105 cm‑1, atomic ratios of Cu/Sb ∼1 and (Cu + Sb)/S ∼1.2, crystal size 18.3–24.5 nm and grain size 50–300 nm. The films were photo-sensitive, showed p-type semiconductor behavior. Electrical resistivity, carrier density and hole mobility were 94–459 Ω cm, 1.6–7.0 × 1015 cm‑3 and 8.4–9.5 cm2 V‑1 s respectively.
Eagle, A A; Tiekink, E R; George, G N; Young, C G
2001-08-27
The complexes TpWO2X react with sulfiding agents such as B2S3 or P4S10 to give the oxothio- and bis(thio)tungsten(VI) complexes TpWOSX (X = Cl(-)) and TpWS2X [X = Cl(-), S2PPh2(-); Tp = hydrotris(3,5-dimethylpyrazol-1-yl)borate]. The reaction of TpWS2Cl with (i) PPh3 in pyridine and (ii) dimethyl sulfoxide affords TpWOSCl in good overall yield. The chloro complexes undergo metathesis with alkali metal salts to yield species of the type TpWOSX and TpWS2X [X = OPh(-), SPh(-), SePh(-), (-)-mentholate]. The diamagnetic complexes exhibit NMR spectra indicative of C(1) (TpWOSX) or C(s) (TpWS2X) symmetry and IR spectra consistent with terminal oxo and thio ligation (nu(W=O), 940-925 cm(-1); nu(W=S) or nu(WS2), 495-475 cm(-1)). Crystals of (R,S)-TpWOS[(-)-mentholate] are monoclinic, space group P2(1), with a = 11.983(2) A, b = 18.100(3) A, c = 13.859(3) A, beta = 91.60(2) degrees, V = 3004.6(8) A(3), and Z = 4. Crystals of TpWS2(OPh)-CH2Cl2 are orthorhombic, space group Pbca, with a = 16.961(4) A, b = 33.098(7) A, c = 9.555(2) A, V = 5364(2) A(3), and Z = 8. The mononuclear, distorted-octahedral tungsten centers are coordinated by a tridentate Tp ligand, an alkoxy or aryloxy ligand, and two terminal chalcogenide ligands. The average W=O and W=S distances are 1.726(7) and 2.125(2) A, respectively, and the O=W=S and S=W=S angles 102.9(3) and 102.9(1) degrees, respectively. The tungsten and sulfur X-ray absorption spectra of TpWOSCl and TpWS2Cl are consistent with the presence of terminal pi-bonded thio ligands in both complexes. The thio complexes generally undergo a reversible one-electron reduction at potentials significantly more positive than their oxo analogues. The chemical, spectroscopic, and electrochemical properties of the complexes are heavily influenced by the presence of W=S pi frontier orbitals.
Multi-objective experimental design for (13)C-based metabolic flux analysis.
Bouvin, Jeroen; Cajot, Simon; D'Huys, Pieter-Jan; Ampofo-Asiama, Jerry; Anné, Jozef; Van Impe, Jan; Geeraerd, Annemie; Bernaerts, Kristel
2015-10-01
(13)C-based metabolic flux analysis is an excellent technique to resolve fluxes in the central carbon metabolism but costs can be significant when using specialized tracers. This work presents a framework for cost-effective design of (13)C-tracer experiments, illustrated on two different networks. Linear and non-linear optimal input mixtures are computed for networks for Streptomyces lividans and a carcinoma cell line. If only glucose tracers are considered as labeled substrate for a carcinoma cell line or S. lividans, the best parameter estimation accuracy is obtained by mixtures containing high amounts of 1,2-(13)C2 glucose combined with uniformly labeled glucose. Experimental designs are evaluated based on a linear (D-criterion) and non-linear approach (S-criterion). Both approaches generate almost the same input mixture, however, the linear approach is favored due to its low computational effort. The high amount of 1,2-(13)C2 glucose in the optimal designs coincides with a high experimental cost, which is further enhanced when labeling is introduced in glutamine and aspartate tracers. Multi-objective optimization gives the possibility to assess experimental quality and cost at the same time and can reveal excellent compromise experiments. For example, the combination of 100% 1,2-(13)C2 glucose with 100% position one labeled glutamine and the combination of 100% 1,2-(13)C2 glucose with 100% uniformly labeled glutamine perform equally well for the carcinoma cell line, but the first mixture offers a decrease in cost of $ 120 per ml-scale cell culture experiment. We demonstrated the validity of a multi-objective linear approach to perform optimal experimental designs for the non-linear problem of (13)C-metabolic flux analysis. Tools and a workflow are provided to perform multi-objective design. The effortless calculation of the D-criterion can be exploited to perform high-throughput screening of possible (13)C-tracers, while the illustrated benefit of multi-objective design should stimulate its application within the field of (13)C-based metabolic flux analysis. Copyright © 2015 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Johnson, T. J.; Wood, K. S.; Ray, P. S.; Ferrara, E. C.; Kerr, M. T.; Cheung, C. C.
2017-11-01
Using data from the Large Area Telescope (LAT), one of the two instruments on board the Fermi Gamma-ray Space Telescope, we have detected a > 100 MeV flare from PSR B1259-63 over the time interval 2017-11-02 01:47:25 UTC to 2017-11-03 06:29:13 UTC with a significance of approximately 10 sigma, a preliminary photon flux (from 100 MeV to 300 GeV) of (3.1 +/- 0.4) x 10^-6 ph/cm^2/s, and a power-law photon index of 2.6 +/- 0.1, quoted uncertainties are statistical only.
Synthesis and X-ray crystal structures of heavy-metal complexes of 1,5,9,13-tetrathiacyclohexadecane
DOE Office of Scientific and Technical Information (OSTI.GOV)
Setzer, W.N.; Tang, Yaping; Grant, G.J.
1991-09-18
Heavy-metal complexes of the macrocyclic tetrathioether 1,5,9,13-tetrathiacyclohexadecane (16S4) have been prepared by reaction of the ligand with the appropriate heavy-metal salts. The complexes [Hg(16S4)](ClO[sub 4])[sub 2], [Cd(16S4)](ClO[sub 4])[sub 2], and (16S4)(HgCl[sub 2])[sub 2] have been synthesized and characterized. Single-crystal X-ray structural studies have been carried out on [Hg(16S4)](ClO[sub 4])[sub 2] and [Cd(16S4)](ClO[sub 4])[sub 2]. Crystal data for [Hg(16S4)](ClO[sub 4])[sub 2]: C[sub 12]H[sub 24]S[sub 4]HgCl[sub 2]O[sub 8]; monoclinic space group C2/c; a = 10.033 (3), b = 13.421 (4), c = 15.960 (4) [angstrom]; [beta] = 96.48 (2)[degree]; Z = 4; R = 0.051. Crystal data for [Cd(16S4)](ClO[sub 4])[sub 2]: C[submore » 12]H[sub 24]S[sub 4]CdCl[sub 2]O[sub 8]; triclinic space group P[bar I]; a = 8.346 (2), b = 8.349 (3), c = 8.688 (2) [angstrom]; [alpha] = 69.87 (2), [beta] = 68.97 (2), [gamma] = 82.33 (2)[degree]; Z = 1; R = 0.043. Molecular mechanics calculations have been carried out on the 16S4 ligand, and the lowest energy conformation is a quadrangular [4444] conformation with the sulfur atoms occupying the corners (exodentate) of the quadrangle.« less
Pazhanisamy, S; Pratt, R F
1989-08-22
The steady-state kinetics of the Enterobacter cloacae P99 beta-lactamase-catalyzed aminolysis of the depsipeptide m-[[(phenylacetyl)glycyl]oxy]benzoic acid by D-phenylalanine were consistent with an ordered sequential mechanism with D-phenylalanine binding first [Pazhanisamy, S., Govardhan, C. P., & Pratt, R. F. (1989) Biochemistry (first of three papers in this issue)]. In terms of this mechanism, the kinetics data required that in 20 mM MOPS buffer, pH 7.5, the dissociation constant of the initially formed enzyme/D-phenylalanine complex be around 1.3 mM; at pH 9.0 in 0.1 M carbonate buffer, the complex should be somewhat more stable. Attempts to detect this complex in a binary mixture by spectroscopic methods (fluorescence, circular dichroic, and nuclear magnetic resonance spectra) failed. Kinetic methods were also unsuccessful--the presence of 20 mM D-phenylalanine did not appear to affect beta-lactamase activity nor inhibition of the enzyme by phenylmethanesulfonyl fluoride, phenylboronic acid, or (3-dansylamidophenyl)boronic acid. Equilibrium dialysis experiments appeared to indicate that the dissociation constant of any binary enzyme/D-phenylalanine complex must be somewhat higher than the kinetics allowed (greater than 2 mM). Since the kinetics also required that, at high depsipeptide concentrations, and again with the assumption of the ordered sequential mechanism, the reaction of the enzyme/D-phenylalanine complex to aminolysis products be faster than its reversion to enzyme and D-phenylalanine, a double-label isotope-trapping experiment was performed.(ABSTRACT TRUNCATED AT 250 WORDS)
NASA Astrophysics Data System (ADS)
Chandrasekhar, Sosale; Chopra, Deepak; Gopalaiah, Kovuru; Guru Row, Tayur N.
2007-06-01
Evidence for the generalized anomeric effect (GAE) in the N-acyl-1,3-thiazolidines, an important structural motif in the penicillins, was sought in the crystal structures of N-(4-nitrobenzoyl)-1,3-thiazolidine and its (2:1) complex with mercuric chloride, N-acetyl-2-phenyl-1,3-thiazolidine, and the (2:1) complex of N-benzoyl-1,3-thiazolidine with mercuric bromide. An inverse relationship was generally observed between the C2- N and C2- S bond lengths of the thiazolidine ring, supporting the existence of the GAE. (Maximal bond length changes were ˜0.04 Å for C2- N3, S1- C2, and ˜0.08 Å for N3- C6.) Comparison with N-acylpyrrolidines and tetrahydrothiophenes indicates that both the nitrogen-to-sulphur and sulphur-to-nitrogen GAE's operate simultaneously in the 1,3-thiazolidines, the former being dominant. (This is analogous to the normal and exo-anomeric effects in pyranoses, and also leads to an interesting application of Baldwin's rules.) The nitrogen-to-sulphur GAE is generally enhanced in the mercury(II) complexes (presumably via coordination at the sulphur); a 'competition' between the GAE and the amide resonance of the N-acyl moiety is apparent. There is evidence for a 'push-pull' charge transfer between the thiazolidine moieties in the mercury(II) complexes, and for a 'back-donation' of charge from the bromine atoms to the thiazolidine moieties in the HgBr 2 complex. (The sulphur atom appears to be sp 2 hybridised in the mercury(II) complexes, possibly for stereoelectronic reasons.) These results are apparently relevant to the mode of action of the penicillins.
Visualization of the significance of Receiver Operating Characteristics based on confidence ellipses
NASA Astrophysics Data System (ADS)
Sarlis, Nicholas V.; Christopoulos, Stavros-Richard G.
2014-03-01
The Receiver Operating Characteristics (ROC) is used for the evaluation of prediction methods in various disciplines like meteorology, geophysics, complex system physics, medicine etc. The estimation of the significance of a binary prediction method, however, remains a cumbersome task and is usually done by repeating the calculations by Monte Carlo. The FORTRAN code provided here simplifies this problem by evaluating the significance of binary predictions for a family of ellipses which are based on confidence ellipses and cover the whole ROC space. Catalogue identifier: AERY_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AERY_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 11511 No. of bytes in distributed program, including test data, etc.: 72906 Distribution format: tar.gz Programming language: FORTRAN. Computer: Any computer supporting a GNU FORTRAN compiler. Operating system: Linux, MacOS, Windows. RAM: 1Mbyte Classification: 4.13, 9, 14. Nature of problem: The Receiver Operating Characteristics (ROC) is used for the evaluation of prediction methods in various disciplines like meteorology, geophysics, complex system physics, medicine etc. The estimation of the significance of a binary prediction method, however, remains a cumbersome task and is usually done by repeating the calculations by Monte Carlo. The FORTRAN code provided here simplifies this problem by evaluating the significance of binary predictions for a family of ellipses which are based on confidence ellipses and cover the whole ROC space. Solution method: Using the statistics of random binary predictions for a given value of the predictor threshold ɛt, one can construct the corresponding confidence ellipses. The envelope of these corresponding confidence ellipses is estimated when ɛt varies from 0 to 1. This way a new family of ellipses is obtained, named k-ellipses, which covers the whole ROC plane and leads to a well defined Area Under the Curve (AUC). For the latter quantity, Mason and Graham [1] have shown that it follows the Mann-Whitney U-statistics [2] which can be applied [3] for the estimation of the statistical significance of each k-ellipse. As the transformation is invertible, any point on the ROC plane corresponds to a unique value of k, thus to a unique p-value to obtain this point by chance. The present FORTRAN code provides this p-value field on the ROC plane as well as the k-ellipses corresponding to the (p=)10%, 5% and 1% significance levels using as input the number of the positive (P) and negative (Q) cases to be predicted. Unusual features: In some machines, the compiler directive -O2 or -O3 should be used to avoid NaN’s in some points of the p-field along the diagonal. Running time: Depending on the application, e.g., 4s for an Intel(R) Core(TM)2 CPU E7600 at 3.06 GHz with 2 GB RAM for the examples presented here References: [1] S.J. Mason, N.E. Graham, Quart. J. Roy. Meteor. Soc. 128 (2002) 2145. [2] H.B. Mann, D.R. Whitney, Ann. Math. Statist. 18 (1947) 50. [3] L.C. Dinneen, B.C. Blakesley, J. Roy. Stat. Soc. Ser. C Appl. Stat. 22 (1973) 269.
Alizadeh, Nina
2011-01-01
Lithium-7 NMR measurements were used to investigate the stoichiometry and stability of Li+ complexes with 15-crown-5 (15C5), benzo-15-crown-5 (B15C5), dibenzo-15-crown-5 (DB15C5) and 12-crown-4 (12C4) in a number of nitromethane (NM)-acetonitrile (AN) binary mixtures. In all cases, the exchange between the free and complexed lithium ion was fast on the NMR time scale and a single population average resonance was observed. While all crown ethers form 1:1 complexes with Li+ ion in the binary mixtures used, both 1:1 and 2:1 (sandwich) complexes were observed between lithium ion and 12C4 in pure nitromethane solution. Stepwise formation constants of the 1:1 and 2:1 (ligand/metal) complexes were evaluated from computer fitting of the NMR-mole ratio data to equations which relate the observed metal ion chemical shifts to formation constants. There is an inverse linear relationship between the logarithms of the stability constants and the mole fraction of acetonitrile in the solvent mixtures. The stability order of the 1:1 complexes was found to be 15C5·Li+>B15C5·Li+>DB15C5·Li+>12C4·Li+. The optimized structures of the free ligands and their 1:1 and 2:1 complexes with Li+ ion were predicted by ab initio theoretical calculations using the Gaussian 98 software, and the results are discussed. Copyright © 2010 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Sathiyaraj, E.; Thirumaran, S.; Selvanayagam, S.; Sridhar, B.; Ciattini, Samuele
2018-05-01
New bis(N-benzyl-N-substituted benzyldithiocarbamato-S,S‧)nickel(II) (1-3) and (N-benzyl-N-substituted benzyldithiocarbamato-S,S‧)(isothiocyanato-N)- (triphenylphosphane)nickel(II) (4-6) [where substituted benzyl = 2-HOsbnd C6H4sbnd CH2sbnd (1,4), 3-HOsbnd C6H4sbnd CH2sbnd (2,5), 4-Fsbnd C6H4sbnd CH2sbnd (3,6)] were synthesized and characterized using IR, electronic, and NMR (1H and 13C) spectra. X-ray structural analysis of homoleptic complex (1) and heteroleptic complexes (5 and 6) confirmed the presence of four coordinated nickel in a distorted square planar arrangement with NiS4 and NiS2PN chromophores, respectively. The νC-S stretching vibrations are observed around 990 cm-1 without any splitting supporting the bidentate coordination of the dithiocarbamate ligand. Electronic spectral studies of all the complexes (1-6) indicate that the geometry of the nickel atom is probably square planar. NMR spectra of all homoleptic and heteroleptic complexes (1-6) reveal a weak signal associated with the backbone carbon (N13CS2) in the region 204.0-210.0 ppm with a weak intensity characteristic of the quaternary carbon signals. The greater trans influence of triphenylphosphine in complexes 5 and 6 is supported by the long Nisbnd S distance compared to other Nisbnd S distance which is opposite to the NCS- ligand. In the structure of complex 5, C-H⋯π(chelate) interactions results in polymeric chain. Both structures show intramolecular Ni⋯H interactions but that on 6 is the strongest. C-H⋯π interactions are also found in 1, 5 and 6. Hirshfeld surface analysis and the associated 2D fingerprint plots of 1, 5 and 6 have been studied to evaluate intermolecular interactions. The molecular geometries of complexes 1, 5 and 6 have been optimized by abinitio HF method using LANL2DZ program.
Carbon Isotope Discrimination in C3 Land Plants is Independent of Atmospheric PCO2
NASA Astrophysics Data System (ADS)
Kohn, M. J.
2015-12-01
The δ13C of terrestrial C3 plant tissues and soil organic matter is important for understanding the carbon cycle, inferring past climatic and ecological conditions, and predicting responses of vegetation to future climate change. Plant δ13C depends on the δ13C of atmospheric CO2 and mean annual precipitation (MAP), but an unresolved decades-long debate centers on whether terrestrial C3 plant δ13C responds to pCO2. Here, the pCO2-dependence of C3 land plant δ13C was tested using isotopic records from low- and high-pCO2 times spanning historical through Eocene data. Historical data do not resolve a clear pCO2-effect (-1.2±1.0 to 0.59±0.34‰/100 ppmv), and organic carbon records of the Pleistocene-Holocene transition implicate changes in MAP and ecosystems, rather than pCO2, as the major driver of δ13C changes. Fossil collagen and tooth enamel data constrain pCO2-effects most tightly to -0.03±0.13 and -0.03±0.24‰/100 ppmv between 200 and 700 ppmv. Combining all constraints yields a preferred value of 0.0±0.2‰/100 ppmv (2 s.e.), i.e. there is effectively no pCO2 effect. Recent models of pCO2-dependence imply unrealistic MAP for Cenozoic records.
Nestorovich, Ekaterina M.; Karginov, Vladimir A.; Popoff, Michel R.; Bezrukov, Sergey M.; Barth, Holger
2011-01-01
Background Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin are binary exotoxins, which ADP-ribosylate actin in the cytosol of mammalian cells and thereby destroy the cytoskeleton. C2 and iota toxin consists of two individual proteins, an enzymatic active (A-) component and a separate receptor binding and translocation (B-) component. The latter forms a complex with the A-component on the surface of target cells and after receptor-mediated endocytosis, it mediates the translocation of the A-component from acidified endosomal vesicles into the cytosol. To this end, the B-components form heptameric pores in endosomal membranes, which serve as translocation channels for the A-components. Methodology/Principal Findings Here we demonstrate that a 7-fold symmetrical positively charged ß-cyclodextrin derivative, per-6-S-(3-aminomethyl)benzylthio-ß-cyclodextrin, protects cultured cells from intoxication with C2 and iota toxins in a concentration-dependent manner starting at low micromolar concentrations. We discovered that the compound inhibited the pH-dependent membrane translocation of the A-components of both toxins in intact cells. Consistently, the compound strongly blocked transmembrane channels formed by the B-components of C2 and iota toxin in planar lipid bilayers in vitro. With C2 toxin, we consecutively ruled out all other possible inhibitory mechanisms showing that the compound did not interfere with the binding of the toxin to the cells or with the enzyme activity of the A-component. Conclusions/Significance The described ß-cyclodextrin derivative was previously identified as one of the most potent inhibitors of the binary lethal toxin of Bacillus anthracis both in vitro and in vivo, implying that it might represent a broad-spectrum inhibitor of binary pore-forming exotoxins from pathogenic bacteria. PMID:21887348
NASA Astrophysics Data System (ADS)
Shebl, Magdy; Adly, Omima M. I.; Taha, A.; Elabd, N. N.
2017-11-01
The compound in the title (L) was synthesized and reacted with Cu(II) metal ion with different anions (OAc-, NO3-, SO42-, ClO4-, Cl- and Br-) in absence and presence of auxiliary ligands (L‧); N,O-donor; or N,N-donor; to form binary and ternary Cu(II)-chelates. The metal complexes were fully characterized by analytical and spectral techniques in addition to thermal, conductivity and magnetic susceptibility measurements. The obtained results showed that the ligand behaves as a neutral bidentate, forming chelates with molar ratios: 1:1, 1:2 and 1:3; M:L for binary and 1:2:1 and 1:1:1; M:L:L‧ for ternary complexes, which can be formulated as: [LmCuXn(H2O)y]·zH2O, m = 1 or 2, n = 0, 1 or 2, X = OAc-, SO42-, Cl- or Br-, y = 0 or 2, z = 0 or 0.5; [LmCu(H2O)n]X2·zMeOH, m = 2 or 3, n = 0 or 2, X = ClO4- or NO3-, z = 0 or 1 and [Lm L'Cu(H2O)n](NO3)x·yS, m = 1 or 2, n = 0 or 2, X = 1 or 2, y = 0.5 or 4, S = H2O or MeOH. The ESR spin Hamiltonian parameters of some complexes were calculated. Kinetic parameters (Ea, A, ΔH, ΔS and ΔG) of the thermal decomposition stages have been evaluated using Coats-Redfern equations. The structural parameters of the ligand and its metal complexes have been calculated and correlated with the experimental data. The metal complexes exhibited octahedral and square planar geometrical arrangements according to the nature of the anion. The ligand and its metal complexes showed antibacterial activity towards Gram-positive bacteria, Gram-negative bacteria, yeast and fungus.
Yan, Qi-Long; Xiao-Jiang, Li; La-Ying, Zhang; Ji-Zhen, Li; Hong-Li, Li; Zi-Ru, Liu
2008-12-30
The compatibility of trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin (TNAD) with some energetic components and inert materials of solid propellants was studied by using the pressure DSC method where, cyclotetramethylenetetranitroamine (HMX), cyclotrimethylenetrinitramine (RDX), 1,4-dinitropiperazine (DNP), 1.25/1-NC/NG mixture, lead 3-nitro-1,2,4-triazol-5-onate (NTO-Pb), aluminum powder (Al, particle size=13.6microm) and N-nitrodihydroxyethylaminedinitrate (DINA) were used as energetic components and polyethylene glycol (PEG), polyoxytetramethylene-co-oxyethylene (PET), addition product of hexamethylene diisocyanate and water (N-100), 2-nitrodianiline (2-NDPA), 1,3-dimethyl-1,3-diphenyl urea (C2), carbon black (C.B.), aluminum oxide (Al2O3), cupric 2,4-dihydroxy-benzoate (beta-Cu), cupric adipate (AD-Cu) and lead phthalate (phi-Pb) were used as inert materials. It was concluded that the binary systems of TNAD with NTO-Pb, RDX, PET and Al powder are compatible, and systems of TNAD with DINA and HMX are slightly sensitive, and with 2-NDPA, phi-Pb, beta-Cu, AD-Cu and Al2O3 are sensitive, and with PEG, N-100, C2 and C.B. are incompatible. The impact and friction sensitivity data of the TNAD and TNAD in combination with the other energetic materials under present study was also obtained, and there was no consequential affiliation between sensitivity and compatibility.
Li, Li; Wang, Lecai; Zhang, Xiaoxiao; Xie, Man; Wu, Feng; Chen, Renjie
2015-10-07
In this study, a facile nanoetching-template route is developed to synthesize porous nanomicrohierarchical LiNi1/3Co1/3Mn1/3O2 microspheres with diameters below 1.5 μm, using porous CoMnO3 binary oxide microspheres as the template. The unique morphology of CoMnO3 template originates from the contraction effect during the oxidative decomposition of Ca0.2Mn0.4Co0.4CO3 precursors and is further improved by selectively removing calcium carbonate with a nanoetching process after calcination. The as-synthesized LiNi1/3Co1/3Mn1/3O2 microsphere, composed of numerous primary particles and pores with size of dozens of nanometers, illustrates a well-assembled porous nanomicrohierarchical structure. When used as the cathode material for lithium-ion batteries, the as-synthesized microspheres exhibit remarkably enhanced electrochemical performances with higher capacity, excellent cycling stability, and better rate capability, compared with the bulk counterpart. Specifically, hierarchical LiNi1/3Co1/3Mn1/3O2 achieves a high discharge capacity of 159.6 mA h g(-1) at 0.2 C with 98.7% capacity retention after 75 cycles and 133.2 mA h g(-1) at 1 C with 90% capacity retention after 100 cycles. A high discharge capacity of 135.5 mA h g(-1) even at a high current of 750 mA g(-1) (5 C) is also achieved. The nanoetching-template method can provide a general approach to improve cycling stability and rate capability of high capacity cathode materials for lithium-ion batteries.
Exploration of phase transition in Th2C under pressure: An Ab-initio investigation
NASA Astrophysics Data System (ADS)
Sahoo, B. D.; Joshi, K. D.; Kaushik, T. C.
2018-05-01
With the motivation of searching for new compounds in the Th-C system, we have performed ab initio evolutionary searches for all the stable compounds in this binary system in the pressure range of 0-100 GPa. We have found previously unknown, thermodynamically stable, composition Th2C along with experimentally known ThC, ThC2 and Th2C3 phases at 0 GPa. Interestingly at pressure of 13 GPa the predicted ground state orthorhombic (SG no. 59, Pmmn) phase of Th2C transforms to trigonal (SG no. 164, P-3m1) phase. We also find the mechanical and dynamical stability of both the phases. Further, the theoretically determined equation of state has been utilized to derive various physical quantities such as zero pressure equilibrium volume, bulk modulus, and pressure derivative of bulk modulus of Pmmn phase at ambient conditions.
NASA Astrophysics Data System (ADS)
Shah, N. S.; Vankar, H. P.; Rana, V. A.
2017-05-01
The complex relative dielectric function ɛ*(ω)=ɛ'-jɛ″ of the binary mixture of 2-chloroaniline(2-CA) and methanol (MeOH) were measured using precision LCR meter in the frequency range of 10 KHz to 2 MHz The measurements were carried out at eight different temperatures and five different concentrations of 2-CA and MeOH. The loss tangent peaks were observed in the studied frequency range for all the binary mixtures. From the loss tangent peaks electrode polarization relaxation time were evaluated. In the plot of real part of complex permittivity against frequency, at different temperatures for 2-CA (54.54%) + MeOH (45.45%) and 2-CA (27.27%) + MeOH (72.72%)and 100% MeOH systems permittivity inversion effect was observed.
CD44 Promotes intoxication by the clostridial iota-family toxins.
Wigelsworth, Darran J; Ruthel, Gordon; Schnell, Leonie; Herrlich, Peter; Blonder, Josip; Veenstra, Timothy D; Carman, Robert J; Wilkins, Tracy D; Van Nhieu, Guy Tran; Pauillac, Serge; Gibert, Maryse; Sauvonnet, Nathalie; Stiles, Bradley G; Popoff, Michel R; Barth, Holger
2012-01-01
Various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. Separate binding/translocation (B) components bind to a protein receptor on the cell surface, assemble with enzymatic (A) component(s), and mediate endocytosis of the toxin complex. Ultimately there is translocation of A component(s) from acidified endosomes into the cytosol, leading to destruction of the actin cytoskeleton. Our results revealed that CD44, a multifunctional surface protein of mammalian cells, facilitates intoxication by the iota family of clostridial binary toxins. Specific antibody against CD44 inhibited cytotoxicity of the prototypical Clostridium perfringens iota toxin. Versus CD44(+) melanoma cells, those lacking CD44 bound less toxin and were dose-dependently resistant to C. perfringens iota, as well as Clostridium difficile and Clostridium spiroforme iota-like, toxins. Purified CD44 specifically interacted in vitro with iota and iota-like, but not related Clostridium botulinum C2, toxins. Furthermore, CD44 knockout mice were resistant to iota toxin lethality. Collective data reveal an important role for CD44 during intoxication by a family of clostridial binary toxins.
CD44 Promotes Intoxication by the Clostridial Iota-Family Toxins
Wigelsworth, Darran J.; Ruthel, Gordon; Schnell, Leonie; Herrlich, Peter; Blonder, Josip; Veenstra, Timothy D.; Carman, Robert J.; Wilkins, Tracy D.; Van Nhieu, Guy Tran; Pauillac, Serge; Gibert, Maryse; Sauvonnet, Nathalie; Stiles, Bradley G.; Popoff, Michel R.; Barth, Holger
2012-01-01
Various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. Separate binding/translocation (B) components bind to a protein receptor on the cell surface, assemble with enzymatic (A) component(s), and mediate endocytosis of the toxin complex. Ultimately there is translocation of A component(s) from acidified endosomes into the cytosol, leading to destruction of the actin cytoskeleton. Our results revealed that CD44, a multifunctional surface protein of mammalian cells, facilitates intoxication by the iota family of clostridial binary toxins. Specific antibody against CD44 inhibited cytotoxicity of the prototypical Clostridium perfringens iota toxin. Versus CD44+ melanoma cells, those lacking CD44 bound less toxin and were dose-dependently resistant to C. perfringens iota, as well as Clostridium difficile and Clostridium spiroforme iota-like, toxins. Purified CD44 specifically interacted in vitro with iota and iota-like, but not related Clostridium botulinum C2, toxins. Furthermore, CD44 knockout mice were resistant to iota toxin lethality. Collective data reveal an important role for CD44 during intoxication by a family of clostridial binary toxins. PMID:23236484
NASA Astrophysics Data System (ADS)
Powers, H.; McDowell, N.; Breecker, D. O.
2010-12-01
We test the hypothesis that soils collected near dead and living pinus edulous (piñon pine) trees should show a difference in their capacities to decompose complex carbon compounds. Since soils near dead trees have a large amount of cellulose and other complex carbon, the soil microbial community should be selected to metabolize cellulose. We collected soils from both live and dead piñon trees, added cellulose to half of the replicates, and placed them in microcosms for incubation. The microcosms were periodically sampled by a trace gas analyzer (TGA100, Campbell Scientific, USA) for CO2 concentration and δ13C and δ18O analysis. We found that CO2 evolution rates from live soils were significantly higher than rates from dead soils (1.1 and 0.6 ug CO2 g-1 soil s-1 respectively); soils with added cellulose displayed higher rates (1.1 and 0.8 and ug CO2 g-1 soil s-1). We did not see any significant differences in δ13C values between treatments, but there was a difference in δ18O between soils treated with cellulose and soils with no cellulose. Soils from both dead and live trees showed an increase in CO2 efflux when cellulose was added; however there was no distinguishable difference in efflux rate between live and dead soils in the cellulose added treatments.
Eta Carinae: A Box of Puzzles...Some Solved, Others Await
NASA Technical Reports Server (NTRS)
Gull, Theodore
2010-01-01
In the l840's, Eta Carinae brightened to rival Sirius, then faded. Today we see a marginally naked-eye binary with an expanding, very dusty bipolar Homunculus. The energetics of the ejected mass (>l2 to 40 solar masses at 500-700 km/s plus outer bullets/strings up to 3000 km/s} approach that of a supernova. Extragalactic SN surveys detect near-supernovae thought to be like the Great Eruption of the 1840's. Eta Carinae presents an abundance of puzzles: rich in N, but 1/100th the solar C and O abundances; Ti, V, Sr, Sc persist in atomic states.... yet an abundance of molecules and dust exists in the Homunculus. How did molecules and dust form with low C and O? A near supernova occurred in the l840m, yet both binary companions, with total mass > 120 solar masses, survive in a very eccentric orbit. What is the near future of this system: a GRB? a SN? or just two WR stars that ultimately become two SNs? These and other puzzles will be presented
DOE Office of Scientific and Technical Information (OSTI.GOV)
Esclapez, Julia; Britton, K. Linda; Baker, Patrick J.
2005-08-01
Single crystals of binary and ternary complexes of wild-type and D38C mutant H. mediterranei glucose dehydrogenase have been obtained by the hanging-drop vapour-diffusion method. Haloferax mediterranei glucose dehydrogenase (EC 1.1.1.47) belongs to the medium-chain alcohol dehydrogenase superfamily and requires zinc for catalysis. In the majority of these family members, the catalytic zinc is tetrahedrally coordinated by the side chains of a cysteine, a histidine, a cysteine or glutamate and a water molecule. In H. mediterranei glucose dehydrogenase, sequence analysis indicates that the zinc coordination is different, with the invariant cysteine replaced by an aspartate residue. In order to analyse themore » significance of this replacement and to contribute to an understanding of the role of the metal ion in catalysis, a range of binary and ternary complexes of the wild-type and a D38C mutant protein have been crystallized. For most of the complexes, crystals belonging to space group I222 were obtained using sodium/potassium citrate as a precipitant. However, for the binary and non-productive ternary complexes with NADPH/Zn, it was necessary to replace the citrate with 2-methyl-2,4-pentanediol. Despite the radical change in conditions, the crystals thus formed were isomorphous.« less
Huang, Dan; Yang, Yan; Sun, Jian; Dong, Xiaorong; Wang, Jiao; Liu, Hongchen; Lu, Chengquan; Chen, Xueyu; Shao, Jing; Yan, Jinsong
2017-09-01
Aberrant expression of annexin A2-S100A10 heterotetramer (AIIt) associated with PML/RARα fusion protein causes lethal hyperfibrinolysis in acute promyelocytic leukemia (APL), but the mechanism is unclear. To facilitate the investigation of regulatory association between ANXA2 and promyelocytic leukemia/retinoic acid receptor a (PML/RARα) fusion protein, this work was performed to determine the transcription start site of ANXA2 promoter with rapid amplification of 5'-cDNA ends analysis. Zinc-induced U937/PR9 cells expressed PML/RARα fusion protein, and resultant increases in ANXA2 transcripts and translational expressions of both ANXA2 and S100A10, while S100A10 transcripts remained constitutive. The transactivation of ANXA2 promoter by PML/RARα fusion protein was 3.29 ± 0.13 fold higher than that by control pSG5 vector or wild-type RARα. The overexpression of ANXA2 in U937 transfected with full-length ANXA2 cDNA was associated with increased S100A10 subunit, although S100A10 transcripts remained constitutive. The tPA-dependent initial rate of plasmin generation (IRPG) in zinc-treated U937/PR9 increased by 2.13-fold, and cell invasiveness increased by 27.6%. Antibodies against ANXA2, S100A10, or combination of both all remarkably inhibited the IRPG and invasiveness in U937/PR9 and NB4. Treatment of zinc-induced U937/PR9 or circulating APL blasts with all-trans retinoic acid (ATRA) significantly reduced cell surface ANXA2 and S100A10 and associated reductions in IRPG and invasiveness. Thus, PML/RARα fusion protein transactivated the ANXA2 promoter to upregulate ANXA2 and accumulate S100A10. Increased AIIt promoted IRPG and invasiveness, both of which were partly abolished by antibodies against ANXA2 and S100A10 or by ATRA.
Klementyeva, Svetlana V; Gamer, Michael T; Schmidt, Anna-Corina; Meyer, Karsten; Konchenko, Sergey N; Roesky, Peter W
2014-10-13
The reaction of decamethylytterbocene [(η(5) -C5 Me5 )2 Yb(THF)2 ] with SO2 at low temperature gave two new compounds, namely, the Yb(III) dithionite/sulfinate complex [{(η(5) -C5 Me5 )2 Yb(μ3 ,1κ(2) O(1,3) ,2κ(3) O(2,2',4) -S2 O4 )}2 {(η(5) -C5 Me5 )Yb(μ,1κO,2κO'-C5 Me5 SO2 )}2 ] (1) and the Yb(III) dithionite complex [{(η(5) -C5 Me5 )2 Yb}2 (μ,1κ(2) O(1,3) ,2κ(2) O(2,4) -S2 O4 )] (2). After extraction of 1, the mixture was heated to give the dinuclear tetrasulfinate complex [{(η(5) -C5 Me5 )Yb}2 (μ,κO,κO'-C5 Me5 SO2 )4 ] (3 a). In contrast, from the reaction of [(η(5) -C5 Me5 )2 Eu(THF)2 ] with SO2 only the tetrasulfinate complex [{(η(5) -C5 Me5 )Eu}2 (μ,κO,κO'-C5 Me5 SO2 )4 ] (3 b) was isolated. Two major reaction pathways were observed: 1) reductive coupling of two SO2 molecules to form the dithionite anion S2 O4 (2-) ; and 2) nucleophilic attack of one metallocene C5 Me5 ligand on the sulfur atom of SO2 . The compounds presented are the first dithionite and sulfinate complexes of the f-elements. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The fourfold way of the genetic code.
Jiménez-Montaño, Miguel Angel
2009-11-01
We describe a compact representation of the genetic code that factorizes the table in quartets. It represents a "least grammar" for the genetic language. It is justified by the Klein-4 group structure of RNA bases and codon doublets. The matrix of the outer product between the column-vector of bases and the corresponding row-vector V(T)=(C G U A), considered as signal vectors, has a block structure consisting of the four cosets of the KxK group of base transformations acting on doublet AA. This matrix, translated into weak/strong (W/S) and purine/pyrimidine (R/Y) nucleotide classes, leads to a code table with mixed and unmixed families in separate regions. A basic difference between them is the non-commuting (R/Y) doublets: AC/CA, GU/UG. We describe the degeneracy in the canonical code and the systematic changes in deviant codes in terms of the divisors of 24, employing modulo multiplication groups. We illustrate binary sub-codes characterizing mutations in the quartets. We introduce a decision-tree to predict the mode of tRNA recognition corresponding to each codon, and compare our result with related findings by Jestin and Soulé [Jestin, J.-L., Soulé, C., 2007. Symmetries by base substitutions in the genetic code predict 2' or 3' aminoacylation of tRNAs. J. Theor. Biol. 247, 391-394], and the rearrangements of the table by Delarue [Delarue, M., 2007. An asymmetric underlying rule in the assignment of codons: possible clue to a quick early evolution of the genetic code via successive binary choices. RNA 13, 161-169] and Rodin and Rodin [Rodin, S.N., Rodin, A.S., 2008. On the origin of the genetic code: signatures of its primordial complementarity in tRNAs and aminoacyl-tRNA synthetases. Heredity 100, 341-355], respectively.
Tang, Rowena Pui-Ling; Wong, Keith Man-Chung; Zhu, Nianyong; Yam, Vivian Wing-Wah
2009-05-28
A series of dinuclear platinum(ii) terpyridyl and terpyridyl-crown complexes with 2,2-dicyano-1,1-ethylenedithiolate (i-mnt), 1,3-benzenedithiolate (SC(6)H(4)S-1,3) and N,N-diethyldithiocarbamate (dtc) bridging ligands have been synthesized and characterized. Their photophysical and electrochemical properties, together with that of the related mononuclear platinum(ii) terpyridyl-crown complex and its crown-free analogue, have been studied. The ion-binding properties of the terpyridyl-crown complexes have been determined by electronic absorption spectroscopy and ESI-mass spectrometry. The X-ray crystal structures of [Pt(trpyC[triple bond, length as m-dash]C-benzo-15-crown-5)Cl]PF(6), [{Pt(trpy)}(2)(micro-SC(6)H(4)S-1,3)](PF(6))(2) and [{Pt(trpy)}(2){micro-(i-mnt)}](PF(6))(2) have also been determined.
NASA Astrophysics Data System (ADS)
Semenov, K. N.; Ivanova, N. M.; Charykov, N. A.; Keskinov, V. A.; Kalacheva, S. S.; Duryagina, N. N.; Garamova, P. V.; Kulenova, N. A.; Nabieva, A.
2017-02-01
Concentration dependences of the density of aqueous solutions of bisadducts of light fullerene C60 and essential amino acids are studied by pycnometry. Concentration dependences of the average molar volumes and partial volumes of components (H2O and corresponding bisadducts) are calculated for C60(C6H13N2O2)2-H2O, C60(C4H8NO3)2-H2O, and C60(C5H9NO2)2-H2O binary systems at 25°C. Concentration dependences of the indices of refraction of C60(C6H13N2O2)2-H2O, C60(C4H8NO3)2-H2O, and C60(C5H9NO2)2-H2O binary systems are determined at 25°C. The concentration dependences of specific refraction and molar refraction of bisadducts and aqueous solutions of them are calculated.
Dubey, Pooja; Gupta, Sonu; Singh, Ajai K
2018-03-12
The condensation of anthracene-9-carbaldehyde with 2-(phenylthio/seleno)ethylamine results in Schiff bases [PhS(CH 2 ) 2 C[double bond, length as m-dash]N-9-C 14 H 9 ](L1) and [PhSe(CH 2 ) 2 C[double bond, length as m-dash]N-9-C 14 H 9 ] (L2). On their reaction with [(η 5 -Cp*)IrCl(μ-Cl)] 2 and CH 3 COONa at 50 °C followed by treatment with NH 4 PF 6 , iridacycles, [(η 5 -Cp*)Ir(L-H)][PF 6 ] (1: L = L1; 2: L = L2), result. The same reaction in the absence of CH 3 COONa gives complexes [(η 5 -Cp*)Ir(L)Cl][PF 6 ] (3-4) in which L = L1(3)/L2(4) ligates in a bidentate mode. The ligands and complexes were authenticated with HR-MS and NMR spectra [ 1 H, 13 C{ 1 H} and 77 Se{ 1 H} (in the case of L2 and its complexes only)]. Single crystal structures of L2 and half sandwich complexes 1-4 were established with X-ray crystallography. Three coordination sites of Ir in each complex are covered with η 5 -Cp* and on the remaining three, donor atoms present are: N, S/Se and C - /Cl - , resulting in a piano-stool structure. The moisture and air insensitive 1-4 act as efficient catalysts under mild conditions for base free N-alkylation of amines with benzyl alcohols and transfer hydrogenation (TH) of aldehydes/ketones. The optimum loading of 1-4 as a catalyst is 0.1-0.5 mol% for both the activations. The best reaction temperature is 80 °C for transfer hydrogenation and 100 °C for N-alkylation. The mercury poisoning test supports a homogeneous pathway for both the reactions catalyzed by 1-4. The two catalytic processes are most efficient with 3 followed by 4 > 1 > 2. The mechanism proposed on the basis of HR-MS of the reaction mixtures of the two catalytic processes taken after 1-2 h involves the formation of an alkoxy and hydrido species. The real catalytic species proposed in the case of iridacycles results due to the loss of the Cp* ring.
Crystal Structures of MEK1 Binary and Ternary Complexes with Nucleotides and Inhibitors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fischmann, Thierry O.; Smith, Catherine K.; Mayhood, Todd W.
MEK1 is a member of the MAPK signal transduction pathway that responds to growth factors and cytokines. We have determined that the kinase domain spans residues 35-382 by proteolytic cleavage. The complete kinase domain has been crystallized and its X-ray crystal structure as a complex with magnesium and ATP-{gamma}S determined at 2.1 {angstrom}. Unlike crystals of a truncated kinase domain previously published, the crystals of the intact domain can be grown either as a binary complex with a nucleotide or as a ternary complex with a nucleotide and one of a multitude of allosteric inhibitors. Further, the crystals allow formore » the determination of costructures with ATP competitive inhibitors. We describe the structures of nonphosphorylated MEK1 (npMEK1) binary complexes with ADP and K252a, an ATP-competitive inhibitor (see Table 1), at 1.9 and 2.7 {angstrom} resolution, respectively. Ternary complexes have also been solved between npMEK1, a nucleotide, and an allosteric non-ATP competitive inhibitor: ATP-{gamma}S with compound 1 and ADP with either U0126 or the MEK1 clinical candidate PD325089 at 1.8, 2.0, and 2.5 {angstrom}, respectively. Compound 1 is structurally similar to PD325901. These structures illustrate fundamental differences among various mechanisms of inhibition at the molecular level. Residues 44-51 have previously been shown to play a negative regulatory role in MEK1 activity. The crystal structure of the integral kinase domain provides a structural rationale for the role of these residues. They form helix A and repress enzymatic activity by stabilizing an inactive conformation in which helix C is displaced from its active state position. Finally, the structure provides for the first time a molecular rationale that explains how mutations in MEK may lead to the cardio-facio-cutaneous syndrome.« less
NASA Astrophysics Data System (ADS)
Ansari, Istikhar A.; Sama, Farasha; Raizada, Mukul; Shahid, M.; Rajpoot, Ravi Kant; Siddiqi, Zafar A.
2017-01-01
A series of four homo-dinuclear transition metal complexes with stoichiometry [M2(HL)2(H2O)2] [M = Fe (1), Co (2), Ni (3) and Cu (4); H3L = 2-((2-hydroxybenzylidene)amino)-2-methylpropane-1,3-diol] has been prepared. Ligand (H3L) was obtained by the condensation of 2-amino-2-methyl-1,3-propanediol (H2ampd) with salicylaldehyde. The complexes (1-4) are characterized employing elemental analysis, FTIR, ESI mass, 1H &13C NMR, EPR, UV Visible, TGA, cyclic voltammetry, and magnetic studies. Spectral data ascertained the bonding features and the geometry of the complexes and revealed that all the complexes adopt distorted octahedral geometry with high spin state of metal ions. Thermal and ESI mass data confirmed the proposed stoichiometry of the complexes. Cyclic voltammetric (CV) studies ascertain the formation of MII/MIII quasi-reversible redox couples in solution. The antimicrobial activities of the present complexes have been examined against few bacteria (E. coli, B. subtilis, S. aureus and S. typhymurium) and fungi (C. albicans, A. fumigatus and P. marneffeiin) suggesting that the present compounds show moderate to high antimicrobial properties. Among all the compounds tested, complex (4) exhibited highest antibacterial as well as antifungal activity. Molecular docking studies of the free ligand and the complexes are performed with BDNA.
NASA Astrophysics Data System (ADS)
Kannan, P. P.; Karthick, N. K.; Mahendraprabu, A.; Shanmugam, R.; Elangovan, A.; Arivazhagan, G.
2017-07-01
FTIR spectra of neat acetonitrile (AN), dimethyl sulphoxide (DMSO) and their binary solutions at various mole fractions have been recorded at room temperature. Theoretical calculations have also been carried out on acetonitrile (monomer, dimer), dimethyl sulphoxide (monomer, dimer) and AN - DMSO complex molecules. 1:2 (AN:DMSO) and 2:1 complexation through the red shifting (AN) C - H ⋯ O = S(DMSO) and blue shifting (DMSO) C - H ⋯ N ≡ C(AN) hydrogen bonds has been identified. The experimental and theoretical studies favour the presence of both the monomer and dimer in liquid AN, but only closed dimers in DMSO. The dipole-dipole interactions existed in AN and DMSO dimers disappear in the complex molecules. Partial π bond between S and O atoms, and three lone pair of electrons on oxygen atom of DMSO have been noticed theoretically.
The structure of Ca2+-loaded S100A2 at 1.3-Å resolution.
Koch, Michael; Fritz, Günter
2012-05-01
S100A2 is an EF-hand calcium ion (Ca(2+))-binding protein that activates the tumour suppressor p53. In order to understand the molecular mechanisms underlying the Ca(2+) -induced activation of S100A2, the structure of Ca(2+)-bound S100A2 was determined at 1.3 Å resolution by X-ray crystallography. The structure was compared with Ca(2+) -free S100A2 and with other S100 proteins. Binding of Ca(2+) to S100A2 induces small structural changes in the N-terminal EF-hand, but a large conformational change in the C-terminal EF-hand, reorienting helix III by approximately 90°. This movement is accompanied by the exposure of a hydrophobic cavity between helix III and helix IV that represents the target protein interaction site. This molecular reorganization is associated with the breaking and new formation of intramolecular hydrophobic contacts. The target binding site exhibits unique features; in particular, the hydrophobic cavity is larger than in other Ca(2+)-loaded S100 proteins. The structural data underline that the shape and size of the hydrophobic cavity are major determinants for target specificity of S100 proteins and suggest that the binding mode for S100A2 is different from that of other p53-interacting S100 proteins. Database Structural data are available in the Protein Data Bank database under the accession number 4DUQ © 2012 The Authors Journal compilation © 2012 FEBS.
Ung VÂ, V&acaron;n Ân; Cargill Thompson, Alexander M. W.; Bardwell, David A.; Gatteschi, Dante; Jeffery, John C.; McCleverty, Jon A.; Totti, Federico; Ward, Michael D.
1997-07-30
The magnetic properties of two series of dinuclear complexes, and one trinuclear complex, have been examined as a function of the bridging pathway between the metal centers. The first series of dinuclear complexes is [{Mo(V)(O)(Tp)Cl}(2)(&mgr;-OO)], where "OO" is [1,4-O(C(6)H(4))(n)O](2)(-) (n = 1, 1; n = 2, 3), [4,4'-O(C(6)H(3)-2-Me)(2)O](2)(-) (4), or [1,3-OC(6)H(4)O](2)(-) (2) [Tp = tris(3,5-dimethylpyrazolyl)hydroborate]. The second series of dinuclear complexes is [{Mo(I)(NO)(Tp)Cl}(2)(&mgr;-NN)], where "NN" is 4,4'-bipyridyl (5), 3,3'-dimethyl-4,4'-bipyridine (6), 3,8-phenanthroline (7), or 2,7-diazapyrene (8). The trinuclear complex is [{Mo(V)(O)(Tp)Cl}(3)(1,3,5-C(6)H(3)O(3))] (9), whose crystal structure was determined [9.5CH(2)Cl(2): C(56)H(81)B(3)Cl(13)Mo(3)N(18)O(6); monoclinic, P2(1)/n; a = 13.443, b = 41.46(2), c = 14.314(6) Å; beta = 93.21(3) degrees; V = 7995(5) Å(3); Z = 4; R(1) = 0.106]. In these complexes, the sign and magnitude of the exchange coupling constant J is clearly related to both the topology and the conformation of the bridging ligand [where J is derived from H = -JS(1)().S(2)() for 1-8 and H = -J(S(1)().S(2)() + S(2)().S(3)() + S(1)().S(3)()) for 9]. The values are as follows: 1, -80 cm(-)(1); 2, +9.8 cm(-)(1); 3, -13.2 cm(-)(1); 4, -2.8 cm(-)(1); 5, -33 cm(-)(1); 6, -3.5 cm(-)(1); 7, -35.6 cm(-)(1); 8, -35.0 cm(-)(1); 9, +14.4 cm(-)(1). In particular the following holds: (1) J is negative (antiferromagnetic exchange) across the para-substituted bridges ligands of 1 and 3-8 but positive (ferromagnetic exchange) across the meta-substituted bridging ligands of 2 and 9. (2) J decreases in magnitude dramatically as the bridging ligand conformation changes from planar to twisted (compare 3 and 4, or 6 and 8). These observations are consistent with a spin-polarization mechanism for the exchange interaction, propagated across the pi-system of the bridging ligand by via overlap of bridging ligand p(pi) orbitals with the d(pi) magnetic orbitals of the metals. The EPR spectrum of 9 is characteristic of a quartet species and shows weak Deltam(s) = 2 and Deltam(s) = 3 transitions at one-half and one-third, respectively, of the field strength of the principal Deltam(s) = 1 component.
NASA Astrophysics Data System (ADS)
Derayea, Sayed M.; Omar, Mahmoud A.; Abu-hassan, Ahmed A.
2018-03-01
A simple, sensitive and non-extractive spectrofluorimetric method has been developed and validated for the determination of two psychoanaleptic drugs, atomoxetine and fluvoxamine, in pure forms and pharmaceutical dosage forms. The proposed method is based on the formation of binary complexes between eosin Y and the studied drugs in the presence of a Teorell-Stenhagen buffer. The quenching of the native fluorescence of eosin Y due to complex formation with the studied drugs was measured spectrofluorimetrically at 545 nm after excitation at 302 nm. At the optimum reaction conditions, the fluorescence quenching values (ΔF) and concentrations were rectilinear over the concentration ranges of 0.2-2.2 and 0.3-2.2 µg ml-1 for atomoxetine and fluvoxamine, respectively. The developed method was successfully applied for the determination of the studied drugs in their pharmaceutical formulations with average percentage recoveries of 100.13 ± 0.66 and 99.69 ± 0.44 for atomoxetine and fluvoxamine, respectively (n = 5), without interference from common excipients.
Omar, Mahmoud A.; Abu-hassan, Ahmed A.
2018-01-01
A simple, sensitive and non-extractive spectrofluorimetric method has been developed and validated for the determination of two psychoanaleptic drugs, atomoxetine and fluvoxamine, in pure forms and pharmaceutical dosage forms. The proposed method is based on the formation of binary complexes between eosin Y and the studied drugs in the presence of a Teorell–Stenhagen buffer. The quenching of the native fluorescence of eosin Y due to complex formation with the studied drugs was measured spectrofluorimetrically at 545 nm after excitation at 302 nm. At the optimum reaction conditions, the fluorescence quenching values (ΔF) and concentrations were rectilinear over the concentration ranges of 0.2–2.2 and 0.3–2.2 µg ml−1 for atomoxetine and fluvoxamine, respectively. The developed method was successfully applied for the determination of the studied drugs in their pharmaceutical formulations with average percentage recoveries of 100.13 ± 0.66 and 99.69 ± 0.44 for atomoxetine and fluvoxamine, respectively (n = 5), without interference from common excipients. PMID:29657744
NASA Astrophysics Data System (ADS)
Chakraborty, Shibalik; Boolchand, Punit
2014-03-01
Binary GexS100-x glasses reveal elastic and chemical phase transitions driven by network topology. With increasing Ge content x, well defined rigidity (xc(1) =19.3%) and stress(xc(2) =24.85%) transitions and associated optical elasticity power-laws are observed in Raman scattering. Calorimetric measurements reveal a square-well like minimum with window walls that coincide with the two elastic phase transitions. Molar volumes show a trapezoidal-like minimum with edges that nearly coincide with the reversibility window. These results are signatures of the isostatically rigid nature of the elastic phase formed between the rigidity and stress transitions. Complex Cp measurements show melt fragility index, m(x) to also show a global minimum in the reversibility window, underscoring that melt dynamics encode the elastic behavior of the glass formed at Tg. The strong nature of melts formed in the IP has an important practical consequence; they lead to slow homogenization of non-stoichiometric batch compositions reacted at high temperatures. Homogenization of chalcogenides melts/glasses over a scale of a few microns is a pre-requisite to observe the intrinsic physical properties of these materials. Supported by NSF Grant DMR 0853957.
HCV-like IRESs displace eIF3 to gain access to the 40S subunit
Hashem, Yaser; des Georges, Amedee; Dhote, Vidya; Langlois, Robert; Liao, Hstau Y.; Grassucci, Robert A.; Pestova, Tatyana V.; Hellen, Christopher U.T.; Frank, Joachim
2014-01-01
Hepatitis C virus (HCV) and Classical swine fever virus (CSFV) mRNAs contain related (HCV-like) internal ribosome entry sites (IRESs) that promote 5’-end independent initiation of translation, requiring only a subset of the eukaryotic initiation factors (eIFs) needed for canonical initiation on cellular mRNAs1. Initiation on HCV-like IRESs relies on their specific interaction with the 40S subunit2–8, which places the initiation codon into the P site, where it directly base-pairs with eIF2-bound Met-tRNAiMet to form a 48S initiation complex. However, all HCV-like IRESs also specifically interact with eIF32,5–7,9–12, but the role of this interaction in IRES-mediated initiation has remained unknown. During canonical initiation, eIF3 binds to the 40S subunit as a component of the 43S pre-initiation complex, and comparison of the ribosomal positions of eIF313 and the HCV IRES8 revealed that they overlap, so that their rearrangement would be required for formation of ribosomal complexes containing both components13. Here, we present a cryo-electron microscopy reconstruction of a 40S ribosomal complex containing eIF3 and the CSFV IRES. Strikingly, although the position and interactions of the CSFV IRES with the 40S subunit in this complex are similar to those of the HCV IRES in the 40S/IRES binary complex8, eIF3 is completely displaced from its ribosomal position in the 43S complex, and instead interacts through its ribosome-binding surface exclusively with the apical region of domain III of the IRES. Our results suggest a role for the specific interaction of HCV-like IRESs with eIF3 in preventing ribosomal association of eIF3, which could serve two purposes: relieving the competition between the IRES and eIF3 for a common binding site on the 40S subunit, and reducing formation of 43S complexes, thereby favoring translation of viral mRNAs. PMID:24185006
Orbit of the young very low-mass spectroscopic binary CHXR 74
NASA Astrophysics Data System (ADS)
Joergens, V.; Janson, M.; Müller, A.
2012-01-01
The pre-main sequence star CHXR 74 (M4.25) in Chamaeleon I was found a few years ago to be a very low-mass spectroscopic binary. A determination of its mass would provide a valuable dynamical mass measurement at young ages in the poorly constrained mass regime of <0.3 M⊙. We carried out follow-up radial velocity monitoring with UVES/VLT between 2008 and 2011 and high-resolution adaptive-optic-assisted imaging with NACO/VLT in 2008 with the aim of constraining the binary orbit. We present an orbital solution of the system based on the combined radial velocity data set, which spans more than eleven years of UVES monitoring for CHXR 74. The best-fit Kepler model has an orbital period of 13.1 years, zero eccentricity, and a radial velocity semi-amplitude of 2.2 km s-1. A companion mass M2sini (which is a lower limit due to the unknown orbital inclination i) of 0.08 M⊙ is derived by using a model-dependent mass estimate for the primary of 0.24 M⊙. The binary separation (a1sini + a2) for an inclination of 90° is 3.8 AU, which corresponds to 23 mas. Complementary NACO/VLT images of CHXR 74 were taken with the aim to directly resolve the binary. While there are marginal signs of an extended point spread function (PSF), we have detected no convincing companion to CHXR 74 in the NACO images. From the non-detection of the companion together with a prediction of the binary separation at the time of the NACO observations, we derive an upper limit for the K-band brightness ratio of the two binary components of 0.5. This allows us to estimate an upper limit of the companion mass of 0.14 M⊙ by applying evolutionary models. Thus, we confirm that CHXR 74 is a very low-mass spectroscopic binary and constrain the secondary mass to lie within the range of about 0.08 and 0.14 M⊙. We predict an astrometric signal of the primary between 0.2 and 0.4 mas when taking into account the luminosity of the companion. The Gaia astrometric mission might well be able to solve the astrometric orbit of the primary and in combination with the presented radial velocity data determine an absolute companion mass. Based on observations obtained at the Very Large Telescope of the European Southern Observatory at Paranal, Chile with UVES in program 65.I-0011(A), 72.C-0653(A), 75.C-0851(C), 77.C-0831(A+D), 380.C-0596(A), 082.C-0023(A), 087.C-0962(B), and with NACO in program 380.C-0596(B).
NASA Astrophysics Data System (ADS)
Puls, Angela; Näther, Christian; Kiebach, Ragnar; Bensch, Wolfgang
2006-09-01
The five new thioantimonates(III) ( iprH) 2[Sb 8S 13] ( I), (1,2-dapH) 2[Sb 8S 13] ( II), (1,3-dapH 2)[Sb 8S 13] ( III), (dienH 2)[Sb 8S 13]ṡ1.5H 2O ( IV), and (C 6H 9N 2)[Sb 8S 13]ṡ2.5H 2O ( V) were synthesised under solvothermal conditions ( ipr = iso-propylamine; 1,2-dap = 1,2-diaminopropane; 1,3-dap = 1,3-diaminopropane; dien = diethylentriamine; C 6H 9N 2 = 3-(aminoethyl)-pyridine). The structures of compounds I and II are topological very similar and a central motif is a Sb 10S 10 ring. On both sides of this ring Sb 5S 5 rings are condensed. These rings are connected via Sb 4S 4 rings leading to the sequence Sb 10S 10-Sb 5S 5-Sb 4S 4-Sb 5S 5-Sb 10Sb 10 in the [010] direction. Further interconnection into the two-dimensional [Sb 8S 13] 2- anion produces a large central Sb 18S 18 ring with dimensions of 11ṡ11 Å in both compounds. The two atoms thick layers are linear and stacked along the a axis generating large channels running along [010]. The layered anion of compound III is constructed by interconnection of the SbS 3 and SbS 4 units yielding Sb 19S 19, Sb 14S 14, Sb 13S 13, and Sb 8S 8 rings. The linear layers are two atoms thick and are stacked perpendicular to [001] to form channels running along the same direction. The last two compounds IV and V show a similar network topology. The layered anion is constructed by SbS 3 trigonal pyramids and SbS 4 units. The layer contains a Sb 12S 12 rings as the main structural motif. The corrugated layers extending in the (100) plane are two atoms thick and are stacked in a manner that large tunnels run along [100]. The total potential solvent areas are large and range from 20.7% for III to 35% for II.
Smiderle, Fhernanda R; Sassaki, Guilherme L; van Arkel, Jeroen; Iacomini, Marcello; Wichers, Harry J; Van Griensven, Leo J L D
2010-08-25
An alpha-glucan was isolated from the culinary medicinal mushroom A. bisporus by hot water extraction, ethanol precipitation and DEAE-cellulose chromatography. The resulting material showed a single HMW peak excluded from a Sephadex G50 column that could completely be degraded by alpha-amylase treatment. After heating in 1% SDS a small additional peak of low MW eluted from the G50 column. The monosaccharide composition of the main peak was evaluated by HPLC, and was found to consist of a majority of glucose (97.6%), and a minor proportion of galactose (2.4%). Methylation analysis and degradation by alpha-amylase indicated the presence of an alpha-glucan with a main chain consisting of (1(R)4)-linked units, substituted at O-6 by alpha-D-glucopyranose single-units in the relation 1:8. Mono- (13C-, 1H-NMR) and bidimensional [1H (obs.),13C-HSQC] spectroscopy analysis confirmed the alpha-configuration of the Glcp residues by low frequency resonances of C-1 at delta 100.6, 100.2, and 98.8 ppm and H-1 high field ones at delta 5.06, 5.11, and 4.74 ppm. The DEPT-13C-NMR allowed assigning the non-substituted and O-substituted -CH(2) signals at delta 60.3/60.8 and 66.2 ppm, respectively. Other assignments were attributed to C-2, C-3, C-4, C-5 and C-6 of the non-reducing ends at delta 71.8; 72.8; 70.0; 71.3 and 60.3/60.8 ppm, respectively. The minor proportion of galactose that was demonstrated was probably derived from a complex between the alpha-glucan and a low molecular weight galactan.
Electrical and Magnetic Properties of Binary Amorphous Transition Metal Alloys.
NASA Astrophysics Data System (ADS)
Liou, Sy-Hwang
The electrical, superconductive and magnetic properties of several binary transition metal amorphous and metastable crystalline alloys, Fe(,x)Ti(,100-x) (30 (LESSTHEQ) x (LESSTHEQ) 100), Fe(,x)Zr(,100-x) (20 (LESSTHEQ) x (LESSTHEQ) 93), Fe(,x)Hf(,100-x) (20 (LESSTHEQ) x (LESSTHEQ) 100), Fe(,x)Nb(,100 -x) (22 (LESSTHEQ) x (LESSTHEQ) 85), Ni(,x)Nb(,100-x) (20 (LESSTHEQ) x (LESSTHEQ) 80), Cu(,x)Nb(,100-x) (10 (LESSTHEQ) x (LESSTHEQ) 90) were studied over a wide composition range. Films were made using a magnetron sputtering system, and the structure of the films was investigated by energy dispersive x-ray diffraction. The composition region of each amorphous alloys system was determined and found in good agreement with a model proposed by Egami and Waseda. The magnetic properties and hyperfine interactions in the films were investigated using a conventional Mossbauer spectrometer and a ('57)Co in Rh matrix source. In all Fe-early transition metal binary alloys systems, Fe does not retain its moment in the low iron concentration region and the result is that the critical concentration for magnetic order (x(,c)) is much larger than anticipated from percolation considerations. A direct comparison between crystalline alloys and their amorphous counterparts of the same composition illustrate no clear correlation between crystalline and amorphous states. Pronounced discontinuities in the magnetic properties with variation in Fe content of all Fe-early transition metal alloys at phase boundaries separating amorphous and crystalline states have been observed. This is caused by the differences in the atomic arrangement and the electronic structure between crystalline and amorphous solids. The temperature dependence of resistivity, (rho)(T), of several binary amorphous alloys of Fe-TM (where TM = Ti, Zr, Hf, Nb etc.) has been studied from 2K to 300K. The Fe-poor (x < x(,c)) samples and the Fe-rich (x > x(,c)) samples have distinctive differences in (rho)(T) at low temperature (below 30K). All the magnetic samples show a logarithmic dependence at low temperature that can be described by Kondo scattering. In addition, there is a change in slope of (rho)(T) at a temperature close to the magnetic ordering temperature, indicating a contribution attributed to magnetic ordering. Several Nb-based amorphous alloys (Fe-Nb, Ni-Nb, Cu-Nb) have also been systematically studied. The effect of the magnetic species on superconductivity is investigated. The value of superconducting transition temperature (T(,s)) increases linearly with increasing Nb concentration. (Abstract shortened with permission of author.).
Structural characterization of the mitomycin 7-O-methyltransferase
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Shanteri; Chang, Aram; Goff, Randal D.
2014-10-02
Mitomycins are quinone-containing antibiotics, widely used as antitumor drugs in chemotherapy. Mitomycin-7-O-methyltransferase (MmcR), a key tailoring enzyme involved in the biosynthesis of mitomycin in Streptomyces lavendulae, catalyzes the 7-O-methylation of both C9{beta}- and C9{alpha}-configured 7-hydroxymitomycins. We have determined the crystal structures of the MmcR-S-adenosylhomocysteine (SAH) binary complex and MmcR-SAH-mitomycin A (MMA) ternary complex at resolutions of 1.9 and 2.3 {angstrom}, respectively. The study revealed MmcR to adopt a common S-adenosyl-L-methionine-dependent O-methyltransferase fold and the presence of a structurally conserved active site general acid-base pair is consistent with a proton-assisted methyltransfer common to most methyltransferases. Given the importance of C7 alkylationmore » to modulate mitomycin redox potential, this study may also present a template toward the future engineering of catalysts to generate uniquely bioactive mitomycins.« less
Lead(II) complex formation with l-cysteine in aqueous solution
Jalilehvand, Farideh; Sisombath, Natalie S.; Schell, Adam C.; ...
2015-02-19
The lead(II) complexes formed with the multidentate chelator l-cysteine (H 2Cys) in an alkaline aqueous solution were studied using 207Pb, 13C, and 1H NMR, Pb L III-edge X-ray absorption, and UV–vis spectroscopic techniques, complemented by electrospray ion mass spectrometry (ESI-MS). The H 2Cys/Pb II mole ratios were varied from 2.1 to 10.0 for two sets of solutions with C PbII = 0.01 and 0.1 M, respectively, prepared at pH values (9.1–10.4) for which precipitates of lead(II) cysteine dissolved. At low H 2Cys/Pb II mole ratios (2.1–3.0), a mixture of the dithiolate [Pb(S,N-Cys) 2] 2– and [Pb(S,N,O-Cys)(S-HCys)] – complexes with averagemore » Pb–(N/O) and Pb–S distances of 2.42 ± 0.04 and 2.64 ± 0.04 Å, respectively, was found to dominate. At high concentration of free cysteinate (>0.7 M), a significant amount converts to the trithiolate [Pb(S,N-Cys)(S-HCys) 2] 2–, including a minor amount of a PbS 3-coordinated [Pb(S-HCys) 3] – complex. The coordination mode was evaluated by fitting linear combinations of EXAFS oscillations to the experimental spectra and by examining the 207Pb NMR signals in the chemical shift range δ Pb = 2006–2507 ppm, which became increasingly deshielded with increasing free cysteinate concentration. One-pulse magic-angle-spinning (MAS) 207Pb NMR spectra of crystalline Pb(aet) 2 (Haet = 2-aminoethanethiol or cysteamine) with PbS 2N 2 coordination were measured for comparison (δ iso = 2105 ppm). The UV–vis spectra displayed absorption maxima at 298–300 nm (S – → Pb II charge transfer) for the dithiolate PbS 2N(N/O) species; with increasing ligand excess, a shoulder appeared at ~330 nm for the trithiolate PbS 3N and PbS 3 (minor) complexes. Finally, the results provide spectroscopic fingerprints for structural models for lead(II) coordination modes to proteins and enzymes.« less
Electrical properties of binary mixtures of amino silicone oil and methyl iso butyl ketone
NASA Astrophysics Data System (ADS)
Shah, K. N.; Rana, V. A.; Vankar, H. P.
2018-05-01
The real and imaginary parts of the dielectric function of the binary mixtures of the methyl iso butyl ketone and amino silicone oil in the frequency range 100 Hz to 2 MHz were measured using precision LCR meter at 305.15 K. The electrical properties such as electrical modulus M*(ω), electrical conductivity σ*(ω) and complex impedance Z*(ω) were calculated using the dielectric function ɛ*(ω). The ionic polarization relaxation time (Τσ) and D.C. conductivity (σdc) were also calculated using electrical properties. The ionic behavior of methyl iso butyl ketone and non-ionic behavior of amino silicone oil are also explained. The electrical parameters are used to gain information about the effect of concentration variation of components of the mixtures on the electrical properties.
30+ New & Known SB2s in the SDSS-III/APOGEE M Dwarf Ancillary Science Project Sample
NASA Astrophysics Data System (ADS)
Skinner, Jacob; Covey, Kevin; Bender, Chad; De Lee, Nathan Michael; Chojnowski, Drew; Troup, Nicholas; Badenes, Carles; Mahadevan, Suvrath; Terrien, Ryan
2018-01-01
Close stellar binaries can drive dynamical interactions that affect the structure and evolution of planetary systems. Binary surveys indicate that the multiplicity fraction and typical orbital separation decrease with primary mass, but correlations with higher order architectural parameters such as the system's mass ratio are less well constrained. We seek to identify and characterize double-lined spectroscopic binaries (SB2s) among the 1350 M dwarf ancillary science targets with APOGEE spectra in the SDSS-III Data Release 13. We quantitatively measure the degree of asymmetry in the APOGEE pipeline cross-correlation functions (CCFs), and use those metrics to identify a sample of 44 high-likelihood candidate SB2s. Extracting radial velocities (RVs) for both binary components from the CCF, we then measure mass ratios for 31 SB2s; we also use Bayesian techniques to fit orbits for 4 systems with 8 or more distinct APOGEE observations. The (incomplete) mass ratio distribution of this sample rises quickly towards unity. Two-sided Kolmogorov-Smirnov (K-S) tests find probabilities of 13.8% and 14.2% that the M dwarf mass ratio distribution is consistent with those measured by Pourbaix et al. (2004) and Fernandez et al. (2017), respectively. The samples analyzed by Pourbaix et al. and Fernandez et al. are dominated by higher-mass solar type stars; this suggests that the mass ratio distribution of close binaries is not strongly dependent on primary mass.
Close Binaries in the η Chamaeleontis Cluster
NASA Astrophysics Data System (ADS)
Köhler, Rainer; Petr-Gotzens, Monika G.
2002-11-01
We have used speckle interferometry and adaptive optics observations to search for multiple systems among 13 stars in the η Chamaeleontis cluster. We discovered two previously unknown subarcsecond binaries. Placing the components in infrared color-magnitude diagrams shows that most members of η Cha are coeval. Repeated observations of the binary RECX 1 allow us to determine a preliminary orbit and derive a system mass of about 2 Msolar. Based on observations obtained at the European Southern Observatory, La Silla, proposals 56.E-0197, 62.I-0399, 65.I-0350, 65.I-0086, 67.C-0354, and 68.C-0539.
Synthesis and molecular structure of a spheroidal binary nanoscale copper sulfide cluster.
Bestgen, Sebastian; Fuhr, Olaf; Roesky, Peter W; Fenske, Dieter
2016-09-27
The reaction of copper(4-(tert-butyl)phenyl)methanethiolate [CuSCH 2 C 6 H 4 t Bu] with bis(trimethylsilyl)sulfide S(SiMe 3 ) 2 in the presence of triphenylphosphine PPh 3 afforded the binary 52 nuclear copper cluster [Cu 52 S 12 (SCH 2 C 6 H 4 t Bu) 28 (PPh 3 ) 8 ]. The molecular structure of this intensely red coloured nanoscale Cu 2 S mimic was established by single crystal X-ray diffraction.
Dissolution of nontronite in chloride brines and implications for the aqueous history of Mars
NASA Astrophysics Data System (ADS)
Steiner, M. H.; Hausrath, E. M.; Elwood Madden, M. E.; Tschauner, O.; Ehlmann, B. L.; Olsen, A. A.; Gainey, S. R.; Smith, J. S.
2016-12-01
Increasing evidence suggests the presence of recent liquid water, including brines, on Mars. Brines have therefore likely impacted clay minerals such as the Fe-rich mineral nontronite found in martian ancient terrains. To interpret these interactions, we conducted batch experiments to measure the apparent dissolution rate constant of nontronite at 25.0 °C at activities of water (aH2O) of 1.00 (0.01 M CaCl2 or NaCl), 0.75 (saturated NaCl or 3.00 mol kg-1 CaCl2), and 0.50 (5.00 mol kg-1 CaCl2). Experiments at aH2O = 1.00 (0.01 M CaCl2) were also conducted at 4.0 °C, 25.0 °C, and 45.0 °C to measure an apparent activation energy for the dissolution of nontronite. Apparent dissolution rate constants at 25.0 °C in CaCl2-containing solutions decrease with decreasing activity of water as follows: 1.18 × 10-12 ± 9 × 10-14 mol mineral m-2 s-1 (aH2O = 1.00) > 2.36 × 10-13 ± 3.1 × 10-14 mol mineral m-2 s-1 (aH2O = 0.75) > 2.05 × 10-14 ± 2.9 × 10-15 mol mineral m-2 s-1 (aH2O = 0.50). Similar results were observed at 25.0 °C in NaCl-containing solutions: 1.89 × 10-12 ± 1 × 10-13 mol mineral m-2 s-1 (aH2O = 1.00) > 1.98 × 10-13 ± 2.3 × 10-14 mol mineral m-2 s-1 (aH2O = 0.75). This decrease in apparent dissolution rate constants with decreasing activity of water follows a relationship of the form: log kdiss = 3.70 ± 0.20 × aH2O - 15.49, where kdiss is the apparent dissolution rate constant, and aH2O is the activity of water. The slope of this relationship (3.70 ± 0.20) is within uncertainty of that of other minerals where the relationship between dissolution rates and activity of water has been tested, including forsteritic olivine (log R = 3.27 ± 0.91 × aH2O - 11.00) (Olsen et al., 2015) and jarosite (log R = 3.85 ± 0.43 × aH2O - 12.84) (Dixon et al., 2015), where R is the mineral dissolution rate. This result allows prediction of mineral dissolution as a function of activity of water and suggests that with decreasing activity of water, mineral dissolution will decrease due to the role of water as a ligand in the reaction. Apparent dissolution rate constants in the dilute NaCl solution (1.89 × 10-12 ± 1 × 10-13 mol mineral m-2 s-1) are slightly greater than those in the dilute CaCl2 solutions (1.18 × 10-12 ± 9 × 10-14 mol mineral m-2 s-1). We attribute this effect to the exchange of Na with Ca in the nontronite interlayer. An apparent activation energy of 54.6 ± 1.0 kJ/mol was calculated from apparent dissolution rate constants in dilute CaCl2-containing solutions at temperatures of 4.0 °C, 25.0 °C, and 45.0 °C: 2.33 × 10-13 ± 1.3 × 10-14 mol mineral m-2 s-1 (4.0 °C), 1.18 × 10-12 ± 9 × 10-14 mol mineral m-2 s-1 (25.0 °C), and 4.98 × 10-12 ± 3.8 × 10-13 mol mineral m-2 s-1 (45.0 °C). The greatly decreased dissolution of nontronite in brines and at low temperatures suggests that any martian nontronite found to be perceptibly weathered may have experienced very long periods of water-rock interaction with brines at the low temperatures prevalent on Mars, with important implications for the paleoclimate and long-term potential habitability of Mars.
NASA Astrophysics Data System (ADS)
Rounaghi, G. H.; Dolatshahi, S.; Tarahomi, S.
2014-12-01
The stoichiometry, stability and the thermodynamic parameters of complex formation between cerium(III) cation and cryptand 222 (4,7,13,16,21,24-hexaoxa-1,10-diazabycyclo[8.8.8]-hexacosane) were studied by conductometric titration method in some binary solvent mixtures of dimethylformamide (DMF), 1,2-dichloroethane (DCE), ethyl acetate (EtOAc) and methyl acetate (MeOAc) with methanol (MeOH), at 288, 298, 308, and 318 K. A model based on 1: 1 stoichiometry has been used to analyze the conductivity data. The data have been fitted according to a non-linear least-squares analysis that provide the stability constant, K f, for the cation-ligand inclusion complex. The results revealed that the stability order of [Ce(cryptand 222)]3+ complex changes with the nature and composition of the solvent system. A non-linear relationship was observed between the stability constant (log K f) of [Ce(cryptand 222)]3+ complex versus the composition of the binary mixed solvent. Standard thermodynamic values were obtained from temperature dependence of the stability constant of the complex, show that the studied complexation process is mainly entropy governed and are influenced by the nature and composition of the binary mixed solvent solutions.
Brown, Louise J.; Sale, Ken L.; Hills, Ron; Rouviere, Clement; Song, Likai; Zhang, Xiaojun; Fajer, Piotr G.
2002-01-01
Site-directed spin labeling EPR (SDSL-EPR) was used to determine the structure of the inhibitory region of TnI in the intact cardiac troponin ternary complex. Maeda and collaborators have modeled the inhibitory region of TnI (skeletal 96–112: the structural motif that communicates the Ca2+ signal to actin) as a kinked α-helix [Vassylyev, D., Takeda, S., Wakatsuki, S., Maeda, K. & Maeda, Y. (1998) Proc. Natl. Acad. Sci. USA 95, 4847–4852), whereas Trewhella and collaborators have proposed the same region to be a flexible β-hairpin [Tung, C. S., Wall, M. E., Gallagher, S. C. & Trewhella, J. (2000) Protein Sci. 9, 1312–1326]. To distinguish between the two models, residues 129–145 of cardiac TnI were mutated sequentially to cysteines and labeled with the extrinsic spin probe, MTSSL. Sequence-dependent solvent accessibility was measured as a change in power saturation of the spin probe in the presence of the relaxation agent. In the ternary complex, the 129–137 region followed a pattern characteristic of a regular 3.6 residues/turn α-helix. The following region, residues 138–145, showed no regular pattern in solvent accessibility. Measurements of 4 intradomain distances within the inhibitory sequence, using dipolar EPR, were consistent with an α-helical structure. The difference in side-chain mobility between the ternary (C⋅I⋅T) and binary (C⋅I) complexes revealed a region of interaction of TnT located at the N-terminal end of the inhibitory sequence, residues 130–135. The above findings for the troponin complex in solution do not support either of the computational models of the binary complex; however, they are in very good agreement with a preliminary report of the x-ray structure of the cardiac ternary complex [Takeda, S. Yamashita, A., Maeda, K. & Maeda, Y. (2002) Biophys. J. 82, 832]. PMID:12239350
NASA Astrophysics Data System (ADS)
Farazandeh, R.; Rounaghi, G. H.; Ebrahimi, M.; Basafa, S.
2017-04-01
The complexation reaction of Cd2+ cation with 2-hydroxy-1,4-naphthoquinone (HNQ) was studied in acetonitrile (AN), 2-PrOH, ethyl acetate (EtOAc), EtOH, dimethylformamide (DMF) and in binary solutions AN-2-PrOH, AN-DMF, AN-EtOH, and AN-EtOAc using conductometric method at 15-45°C. The conductance data show that the stoichiometry of the Cd2+ complex with HNQ in all solvent systems is 1 : 1. In the pure solvents the stability of the complex changes in the order AN > 2-PrOH > EtOH > DMF. The stability of the complex at 25°C in the studied mixtures changes in the following order : AN-EtOAc > AN-2-PrOH > AN-EtOH > AN-DMF. These orders are affected by the nature and composition of the solvent systems and by the temperature. From the temperature dependence data, the thermodynamic functions values (Δ H° and Δ S°) for the complex formation were calculated.
NASA Technical Reports Server (NTRS)
Marchis, F.; Enriquez, J. E.; Emery, J. P.; Mueller, M.; Baek, M.; Pollock, J.; Assafin, M.; Matins, R. Vieira; Berthier, J.; Vachier, F.;
2012-01-01
We collected mid-IR spectra from 5.2 to 38 microns using the Spitzer Space Telescope Infrared Spectrograph of 28 asteroids representative of all established types of binary groups. Photometric light curves were also obtained for 14 of them during the Spitzer observations to provide the context of the observations and reliable estimates of their absolute magnitudes. The extracted mid-IR spectra were analyzed using a modified standard thermal model (STM) and a thermophysical model (TPM) that takes into account the shape and geometry of the large primary at the time of the Spitzer observation. We derived a reliable estimate of the size, albedo, and beaming factor for each of these asteroids, representing three main taxonomic groups: C, S, and X. For large (volume-equivalent system diameter Deq > 130 km) binary asteroids, the TPM analysis indicates a low thermal inertia (Lambda < or = approx.100 J/1/2 s/K/sq m2) and their emissivity spectra display strong mineral features, implying that they are covered with a thick layer of thermally insulating regolith. The smaller (surface-equivalent system diameter Deff < 17 km) asteroids also show some emission lines of minerals, but they are significantly weaker, consistent with regoliths with coarser grains, than those of the large binary asteroids. The average bulk densities of these multiple asteroids vary from 0.7-1.7 g/cu cm (P-, C-type) to approx. 2 g/cu cm (S-type). The highest density is estimated for the M-type (22) Kalliope (3.2 +/- 0.9 g/cu cm). The spectral energy distributions (SEDs) and emissivity spectra, made available as a supplement document, could help to constrain the surface compositions of these asteroids.
Vamsikrishna, Narendrula; Kumar, Marri Pradeep; Tejaswi, Somapangu; Rambabu, Aveli; Shivaraj
2016-07-01
A series of novel bivalent metal complexes M(L1)2 and M(L2)2 where M = Cu(II), Ni(II), Co(II) and L1 = 2-((benzo [d] thiazol-6-ylimino)methyl)-4-bromophenol [BTEMBP], L2 = 1-((benzo [d] thiazol-6-ylimino)methyl) naphthalen-2-ol [BTEMNAPP] were synthesized. All the compounds have been characterized by elemental analysis, SEM, Mass, (1)H NMR, (13)C NMR, UV-Vis, IR, ESR, spectral data and magnetic susceptibility measurements. Based on the analytical and spectral data four-coordinated square planar geometry is assigned to all the complexes. DNA binding properties of these complexes have been investigated by electronic absorption spectroscopy, fluorescence and viscosity measurements. It is observed that these binary complexes strongly bind to calf thymus DNA by an intercalation mode. DNA cleavage efficacy of these complexes was tested in presence of H2O2 and UV light by gel electrophoresis and found that all the complexes showed better nuclease activity. Finally the compounds were screened for antibacterial activity against few pathogens and found that the complexes have potent biocidal activity than their free ligands.
Brown Dwarf Binaries from Disintegrating Triple Systems
NASA Astrophysics Data System (ADS)
Reipurth, Bo; Mikkola, Seppo
2015-04-01
Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi-Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to 15,894 at 100 Myr (˜8%). The total binary fraction among freefloating BDs is 0.43, higher than indicated by current observations, which, however, are still incomplete. Also, the gradual breakup of higher-order multiples leads to many more singles, thus lowering the binary fraction. The main threat to newly born triple systems is internal instabilities, not external perturbations. At 1 Myr there are 1325 BD binaries still bound to a star, corresponding to 0.66% of the simulations, but only 253 (0.13%) are stable on timescales >100 Myr. These simulations indicate that dynamical interactions in newborn triple systems of stellar embryos embedded in and accreting from a cloud core naturally form a population of freefloating BD binaries, and this mechanism may constitute a significant pathway for the formation of BD binaries.
The Rotational Spectrum of Ketene Isotopomers with 18O and 13C Revisited
NASA Astrophysics Data System (ADS)
Guarnieri, A.; Huckaufa, A.
2003-06-01
The pure rotational spectra of [18O]ketene, H2C=C18O, [1-13C]ketene, H2C=13CO, and [2-13C]ketene, H213C=CO, have been revisited in the frequency region 200 - 350 GHz in the ground vibrational state. From more than 100 R-branch transitions for each isotopomer a set of rotational and centrifugal distortion constants could be derived using the Watson S-reduction formalism. The values obtained for the rotational constants B and C agree very well with results of former investigations. The agreement is worse with respect to the A constants, but our newly determined A values agree well with the corresponding values of the main species and the 17O isotopomer.
A 100-Gb/s noncoherent silicon receiver for PDM-DBPSK/DQPSK signals.
Klamkin, Jonathan; Gambini, Fabrizio; Faralli, Stefano; Malacarne, Antonio; Meloni, Gianluca; Berrettini, Gianluca; Contestabile, Giampiero; Potì, Luca
2014-01-27
An integrated noncoherent silicon receiver for demodulation of 100-Gb/s polarization-division multiplexed differential quadrature phase-shift keying and polarization-division multiplexed differential binary phase-shift keying signals is demonstrated. The receiver consists of a 2D surface grating coupler, four Mach-Zehnder delay interferometers and four germanium balanced photodetectors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rinker, E.B.; Oelschlager, D.W.; Colussi, A.T.
1994-04-01
Aqueous solutions of N-methyldiethanolamine (MDEA) and diethanolamine (DEA) are widely used in the industrial treatment of acid gas streams containing H[sub 2]S and CO[sub 2]. The density and viscosity of aqueous solutions of N-methyldiethanolamine were measured over the temperature range 60--100 C. The density and viscosity of aqueous solutions of diethanolamine and diethanolamine + N-methyldiethanolamine were measured over the temperature range 20--100 C. The surface tension of aqueous solutions of the above mixtures was measured over the temperature range 20--80 C. The concentration ranges were 10--50 mass % N-methyldiethanolamine, 10--30 mass % diethanolamine, and 50 mass % total amine concentrationmore » with mass ratios of 0.0441--0.5883 (diethanolamine to N-methyldiethanolamine). The measured quantities were found to be in agreement with the literature where data were available.« less
The strength and ductility of polycrystalline NiAl in tension
NASA Technical Reports Server (NTRS)
Schulson, E. M.
1982-01-01
Experiments at temperatures from 20 C to 400 C at two strain rates (.0001/s and .000005/s) establish that: (1) at room temperatures, binary and microalloyed ( 1000 ppm La, Y, Mo, Ti) NiAl shows negligible ductility, independent of grain size over the range 5 to 140 micrometers; (2) at 295 C the tensile elongation of binary 51 Ni/49 Al increases from 1% to about 5% upon decreasing the grain size to below approximately 10 micrometers; (3) similarly, at 400 C the ductility increases from about 2% to 15% upon decreasing the grain size to below 15 micrometers; (4) the ductility of fine grained (7 micrometer) binary aggregates deformed at 295 C increases from approximately 5% to 12% upon decreasing the strain rate from .0001/s to .000005/s; (5) partial recrystallization (10% to 20%) of warm extruded binary and microalloyed material imparts 1% to 2% ductility at room temperature where fully recrystallized material is brittle; (6) the yield strength obeys a Hall-Petch relationship; and (7) when ductility is not observed, fracture coincides with yielding. The mechanisms underlying the flow and fracture of NiAl are discussed in terms of the nucleation and growth of microcracks. The concept of a critical grain size is considered in the light of the results.
Binary dislocation junction formation and strength in hexagonal close-packed crystals
Wu, Chi -Chin; Aubry, Sylvie; Arsenlis, Athanasios; ...
2015-12-17
This work examines binary dislocation interactions, junction formation and junction strengths in hexagonal close-packed ( hcp ) crystals. Through a line-tension model and dislocation dynamics (DD) simulations, the interaction and dissociation of different sets of binary junctions are investigated involving one dislocation on the (011¯0) prismatic plane and a second dislocation on one of the following planes: (0001) basal, (11¯00) prismatic, (11¯01) primary pyramidal, or (2¯112) secondary pyramidal. Varying pairs of Burgers vectors are chosen from among the common types the basal type < a > 1/3 < 112¯0 >, prismatic type < c > <0001>, and pyramidal type
Im, Ha Na; Kim, Hyoun Sook; An, Doo Ri; Jang, Jun Young; Kim, Jieun; Yoon, Hye-Jin; Yang, Jin Kuk; Suh, Se Won
2016-03-01
The Mycobacterium tuberculosis Rv2258c protein is an S-adenosyl-L-methionine (SAM)-dependent methyltransferase (MTase). Here, we have determined its crystal structure in three forms: a ligand-unbound form, a binary complex with sinefungin (SFG), and a binary complex with S-adenosyl-L-homocysteine (SAH). The monomer structure of Rv2258c consists of two domains which are linked by a long α-helix. The N-terminal domain is essential for dimerization and the C-terminal domain has the Class I MTase fold. Rv2258c forms a homodimer in the crystal, with the N-terminal domains facing each other. It also exists as a homodimer in solution. A DALI structural similarity search with Rv2258c reveals that the overall structure of Rv2258c is very similar to small-molecule SAM-dependent MTases. Rv2258c interacts with the bound SFG (or SAH) in an extended conformation maintained by a network of hydrogen bonds and stacking interactions. Rv2258c has a relatively large hydrophobic cavity for binding of the methyl-accepting substrate, suggesting that bulky nonpolar molecules with aromatic rings might be targeted for methylation by Rv2258c in M. tuberculosis. However, the ligand-binding specificity and the biological role of Rv2258c remain to be elucidated due to high variability of the amino acid residues defining the substrate-binding site. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Yoshida, Koji; Sato, Toyoto; Unemoto, Atsushi; Matsuo, Motoaki; Ikeshoji, Tamio; Udovic, Terrence J.; Orimo, Shin-ichi
2017-03-01
In the present work, we developed highly sodium-ion conductive Na2B10H10-Na2B12H12 pseudo-binary complex hydride via mechanically ball-milling admixtures of the pure Na2B10H10 and Na2B12H12 components. Both of these components show a monoclinic phase at room temperature, but ball-milled mixtures partially stabilized highly ion-conductive, disordered cubic phases, whose fraction and favored structural symmetry (body-centered cubic or face-centered cubic) depended on the conditions of mechanical ball-milling and molar ratio of the component compounds. First-principles molecular-dynamics simulations demonstrated that the total energy of the closo-borane mixtures and pure materials is quite close, helping to explain the observed stabilization of the mixed compounds. The ionic conductivity of the closo-borane mixtures appeared to be correlated with the fraction of the body-centered-cubic phase, exhibiting a maximum at a molar ratio of Na2B10H10:Na2B12H12 = 1:3. A conductivity as high as log(σ/S cm-1) = -3.5 was observed for the above ratio at 303 K, being approximately 2-3 orders of magnitude higher than that of either pure material. A bulk-type all-solid-state sodium-ion battery with a closo-borane-mixture electrolyte, sodium-metal negative-electrode, and TiS2 positive-electrode demonstrated a high specific capacity, close to the theoretical value of NaTiS2 formation and a stable discharge/charge cycling for at least eleven cycles, with a high discharge capacity retention ratio above 91% from the second cycle.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reipurth, Bo; Mikkola, Seppo, E-mail: reipurth@ifa.hawaii.edu, E-mail: Seppo.Mikkola@utu.fi
Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi–Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stuntedmore » growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to 15,894 at 100 Myr (∼8%). The total binary fraction among freefloating BDs is 0.43, higher than indicated by current observations, which, however, are still incomplete. Also, the gradual breakup of higher-order multiples leads to many more singles, thus lowering the binary fraction. The main threat to newly born triple systems is internal instabilities, not external perturbations. At 1 Myr there are 1325 BD binaries still bound to a star, corresponding to 0.66% of the simulations, but only 253 (0.13%) are stable on timescales >100 Myr. These simulations indicate that dynamical interactions in newborn triple systems of stellar embryos embedded in and accreting from a cloud core naturally form a population of freefloating BD binaries, and this mechanism may constitute a significant pathway for the formation of BD binaries.« less
Cycling of Volatiles and Stable Isotopes During High-P Subduction Dehydration of Serpentinite
NASA Astrophysics Data System (ADS)
Alt, J.; Garrido, C. J.; Shanks, W. C.; Turchyn, A. V.; López-Sánchez-Vizcaíno, V.; Gómez-Pugnaire, M.
2009-12-01
We present volatile contents and stable isotope compositions of high-P antigorite serpentinites and their chlorite-harzburgite dehydration products from the Cerro del Almirez complex, Spain. The serpentinites are former Tethyan seafoor consisting of antigorite with olivine, diopside, chlorite, magnetite, tremolite, and Ti-clinohumite, dehydrated to chlorite-harzburites comprising spinifex-like olivine + orthopyroxene, with chlorite, tremolite, and magnetite, at T> 650°C and P>2 GPa. The serpentinites have elevated H2O, S, and C contents, averaging (n=10) 1000 ppm S and 10 wt% H2O, and with 180-1280 ppm total C. Bulk δ18O values of 7.9-9.1‰ and δD= -49 to -61‰ are consistent with serpentinization by seawater at 50-100°C. The high sulfide contents and preliminary δ34S analyses of ~10‰ likely reflect microbial reduction of seawater sulfate, and δ13C (total C) values of -10.9 to -20.2‰ are consistent with the presence of an organic carbon component. These data and processes are similar to those for modern seafloor serpentinites. High-P dehydration of the serpentinites resulted in loss of about half of their H2O and S: chlorite-harzburgites (n=11) average 5.7 wt% H2O and 610 ppm S. The δ34S (-5.1 to 10.2‰) and δ18O (6.4-9.5‰) of the metamorphic harzburgites are unchanged from serpentinite, but hydrogen isotopes are fractionated during dehydration, from serpentinite δD values around -55‰ to chlorite-harzburgite values of ~ -70 to -90‰. Carbon contents and δ13C values of the two rock types overlap, with a broad trend of decreasing C contents and δ13C, from ~1200 to 200 ppm and -9.6 to -20.3‰, perhaps reflecting loss of CO2. Our results indicate: 1) significant uptake of H2O, S and C during serpentinization on the seafloor; 2) that recycling of serpentinites to high P and T results in loss of isotopically fractionated sulfur, water and possibly carbon to the sub-arc mantle; and 3) that fractionated sulfur, water and carbon in serpentinite dehydration products can be recycled into the mantle where they can contribute to isotope heterogeneities.
Kaocharoen, Sirada; Ngamskulrungroj, Popchai; Firacative, Carolina; Trilles, Luciana; Piyabongkarn, Dumrongdej; Banlunara, Wijit; Poonwan, Natteewan; Chaiprasert, Angkana; Meyer, Wieland; Chindamporn, Ariya
2013-01-01
To gain a more detailed picture of cryptococcosis in Thailand, a retrospective study of 498 C. neoformans and C. gattii isolates has been conducted. Among these, 386, 83 and 29 strains were from clinical, environmental and veterinary sources, respectively. A total of 485 C. neoformans and 13 C. gattii strains were studied. The majority of the strains (68.9%) were isolated from males (mean age of 37.97 years), 88.5% of C. neoformans and only 37.5% of C. gattii strains were from HIV patients. URA5-RFLP and/or M13 PCR-fingerprinting analysis revealed that the majority of the isolates were C. neoformans molecular type VNI regardless of their sources (94.8%; 94.6% of the clinical, 98.8% of the environmental and 86.2% of the veterinary isolates). In addition, the molecular types VNII (2.4%; 66.7% of the clinical and 33.3% of the veterinary isolates), VNIV (0.2%; 100% environmental isolate), VGI (0.2%; 100% clinical isolate) and VGII (2.4%; 100% clinical isolates) were found less frequently. Multilocus Sequence Type (MLST) analysis using the ISHAM consensus MLST scheme for the C. neoformans/C. gattii species complex identified a total of 20 sequence types (ST) in Thailand combining current and previous data. The Thai isolates are an integrated part of the global cryptococcal population genetic structure, with ST30 for C. gattii and ST82, ST83, ST137, ST141, ST172 and ST173 for C. neoformans being unique to Thailand. Most of the C. gattii isolates were ST7 = VGIIb, which is identical to the less virulent minor Vancouver island outbreak genotype, indicating Thailand as a stepping stone in the global spread of this outbreak strain. The current study revealed a greater genetic diversity and a wider range of major molecular types being present amongst Thai cryptococcal isolates than previously reported. PMID:23861989
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jalilehvand, Farideh; Sisombath, Natalie S.; Schell, Adam C.
The lead(II) complexes formed with the multidentate chelator l-cysteine (H 2Cys) in an alkaline aqueous solution were studied using 207Pb, 13C, and 1H NMR, Pb L III-edge X-ray absorption, and UV–vis spectroscopic techniques, complemented by electrospray ion mass spectrometry (ESI-MS). The H 2Cys/Pb II mole ratios were varied from 2.1 to 10.0 for two sets of solutions with C PbII = 0.01 and 0.1 M, respectively, prepared at pH values (9.1–10.4) for which precipitates of lead(II) cysteine dissolved. At low H 2Cys/Pb II mole ratios (2.1–3.0), a mixture of the dithiolate [Pb(S,N-Cys) 2] 2– and [Pb(S,N,O-Cys)(S-HCys)] – complexes with averagemore » Pb–(N/O) and Pb–S distances of 2.42 ± 0.04 and 2.64 ± 0.04 Å, respectively, was found to dominate. At high concentration of free cysteinate (>0.7 M), a significant amount converts to the trithiolate [Pb(S,N-Cys)(S-HCys) 2] 2–, including a minor amount of a PbS 3-coordinated [Pb(S-HCys) 3] – complex. The coordination mode was evaluated by fitting linear combinations of EXAFS oscillations to the experimental spectra and by examining the 207Pb NMR signals in the chemical shift range δ Pb = 2006–2507 ppm, which became increasingly deshielded with increasing free cysteinate concentration. One-pulse magic-angle-spinning (MAS) 207Pb NMR spectra of crystalline Pb(aet) 2 (Haet = 2-aminoethanethiol or cysteamine) with PbS 2N 2 coordination were measured for comparison (δ iso = 2105 ppm). The UV–vis spectra displayed absorption maxima at 298–300 nm (S – → Pb II charge transfer) for the dithiolate PbS 2N(N/O) species; with increasing ligand excess, a shoulder appeared at ~330 nm for the trithiolate PbS 3N and PbS 3 (minor) complexes. Finally, the results provide spectroscopic fingerprints for structural models for lead(II) coordination modes to proteins and enzymes.« less
Small molecule inhibitors of Ca 2+-S100B reveal two protein conformations
Cavalier, Michael C.; Ansari, Mohd. Imran; Pierce, Adam D.; ...
2016-01-04
The drug pentamidine inhibits calcium-dependent complex formation with p53 ( CaS100B·p53) in malignant melanoma (MM) and restores p53 tumor suppressor activity in vivo. However, off-target effects associated with this drug were problematic in MM patients. Structure–activity relationship (SAR) studies were therefore completed in this study with 23 pentamidine analogues, and X-ray structures of CaS100B·inhibitor complexes revealed that the C-terminus of S100B adopts two different conformations, with location of Phe87 and Phe88 being the distinguishing feature and termed the “FF-gate”. For symmetric pentamidine analogues ( CaS100B· 5a, CaS100B· 6b) a channel between sites 1 and 2 on S100B was occluded bymore » residue Phe88, but for an asymmetric pentamidine analogue ( CaS100B· 17), this same channel was open. Finally, the CaS100B· 17 structure illustrates, for the first time, a pentamidine analog capable of binding the “open” form of the “FF-gate” and provides a means to block all three “hot spots” on CaS100B, which will impact next generation CaS100B·p53 inhibitor design.« less
Small molecule inhibitors of Ca 2+-S100B reveal two protein conformations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cavalier, Michael C.; Ansari, Mohd. Imran; Pierce, Adam D.
The drug pentamidine inhibits calcium-dependent complex formation with p53 ( CaS100B·p53) in malignant melanoma (MM) and restores p53 tumor suppressor activity in vivo. However, off-target effects associated with this drug were problematic in MM patients. Structure–activity relationship (SAR) studies were therefore completed in this study with 23 pentamidine analogues, and X-ray structures of CaS100B·inhibitor complexes revealed that the C-terminus of S100B adopts two different conformations, with location of Phe87 and Phe88 being the distinguishing feature and termed the “FF-gate”. For symmetric pentamidine analogues ( CaS100B· 5a, CaS100B· 6b) a channel between sites 1 and 2 on S100B was occluded bymore » residue Phe88, but for an asymmetric pentamidine analogue ( CaS100B· 17), this same channel was open. Finally, the CaS100B· 17 structure illustrates, for the first time, a pentamidine analog capable of binding the “open” form of the “FF-gate” and provides a means to block all three “hot spots” on CaS100B, which will impact next generation CaS100B·p53 inhibitor design.« less
Dennehy, Mariana; Amo-Ochoa, Pilar; Freire, Eleonora; Suárez, Sebastián; Halac, Emilia; Baggio, Ricardo
2018-02-01
Among the potential applications of coordination polymers, electrical conductivity ranks high in technological interest. We report the synthesis, crystal structure and spectroscopic analysis of an Ag I -thiosaccharinate one-dimensional coordination polymer {systematic name: catena-poly[[[aquatetrakis(μ 3 -1,1-dioxo-1,2-benzisothiazole-3-thiolato-κ 3 N:S 3 :S 3 )tetrasilver(I)]-μ 2 -4,4'-(propane-1,3-diyl)dipyridine-κ 2 N:N'] dimethyl sulfoxide hemisolvate]}, {[Ag 4 (C 7 H 4 NO 2 S 2 ) 4 (C 13 H 14 N 2 )(H 2 O)]·0.5C 2 H 6 OS} n , with the 4,4'-(propane-1,3-diyl)dipyridine ligand acting as a spacer. A relevant feature of the structure is the presence of an unusually short Ag...Ag distance of 2.8306 (9) Å, well within the range of argentophilic interactions, confirmed experimentally as such by a Raman study on the low-frequency spectrum, and corroborated theoretically by an Atoms in Molecules (AIM) analysis of the calculated electron density. Electrical conductivity measurements show that this complex can act as a semiconductor with moderate conductivity.
Molecular basis for the interaction between stress-inducible phosphoprotein 1 (STIP1) and S100A1.
Maciejewski, Andrzej; Prado, Vania F; Prado, Marco A M; Choy, Wing-Yiu
2017-05-16
Stress-inducible phosphoprotein 1 (STIP1) is a cellular co-chaperone, which regulates heat-shock protein 70 (Hsp70) and Hsp90 activity during client protein folding. Members of the S100 family of dimeric calcium-binding proteins have been found to inhibit Hsp association with STIP1 through binding of STIP1 tetratricopeptide repeat (TPR) domains, possibly regulating the chaperone cycle. Here, we investigated the molecular basis of S100A1 binding to STIP1. We show that three S100A1 dimers associate with one molecule of STIP1 in a calcium-dependent manner. Isothermal titration calorimetry revealed that individual STIP1 TPR domains, TPR1, TPR2A and TPR2B, bind a single S100A1 dimer with significantly different affinities and that the TPR2B domain possesses the highest affinity for S100A1. S100A1 bound each TPR domain through a common binding interface composed of α-helices III and IV of each S100A1 subunit, which is only accessible following a large conformational change in S100A1 upon calcium binding. The TPR2B-binding site for S100A1 was predominately mapped to the C-terminal α-helix of TPR2B, where it is inserted into the hydrophobic cleft of an S100A1 dimer, suggesting a novel binding mechanism. Our data present the structural basis behind STIP1 and S100A1 complex formation, and provide novel insights into TPR module-containing proteins and S100 family member complexes. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.
NASA Astrophysics Data System (ADS)
Dagousset, Laure; Pognon, Grégory; Nguyen, Giao T. M.; Vidal, Frédéric; Jus, Sébastien; Aubert, Pierre-Henri
2017-08-01
Electrochemical properties in mesoporous media of three different ionic liquids (1-propyl-1-methylpyrrolidinium-bis(fluorosulfonyl)imide - Pyr13FSI, 1-butyl-1-methylpyrrolidinium-bis(trifluoromethanesulfonyl)imide - Pyr14TFSI and 1-ethyl-3-methylimidazolium-bis(trifluoromethanesulfonyl)imide - EMITFSI) are investigated from -50 °C to 100 °C and compared with binary mixtures with γ-butyrolactone (GBL). Buckypaper composed of Single-Wall Carbon Nanotubes (SWCNTs) are used to prepare and study coin-cell supercapacitors. Supercapacitor using Pyr13FSI/GBL present a rapid loss of capacitance after only a thousand cycles at 100 °C. On the contrary, EMITFSI/GBL and Pyr14TFSI/GBL prove to be very promising at high temperature (the capacitance loss after 10,000 cycles is 9% and 10%). More drastic ageing tests such as floating are also carried out for these two mixtures at 100 °C and -50 °C. 23% and 15% capacitance losses have been recorded after 500 h of floating at 100 °C for EMITFSI/GBL and Pyr14TFSI/GBL. The capacitance of supercapacitors based on Pyr14TFSI/GBL dropped by 20% after 200 h of floating at -50 °C rather than EMITFSI/GBL show a remarkable stability during floating at -50 °C, with 6.6% capacitance loss after 500 h (3 V at -50 °C). These results show that the mixture EMITFSI/GBL works properly all along the broad range of temperature [-50 °C to +100 °C] and thus proved that our approach is very promising for the development of high performances supercapacitors specifically adapted for extreme environment.
Bennett, Chris J; Jamieson, Corey S; Kaiser, Ralf I
2009-06-07
Binary ice mixtures of two carbon monoxide isotopomers, (13)C(16)O and (12)C(18)O, were subjected at 10 K to energetic electrons to investigate the interaction of ionizing radiation with extraterrestrial, carbon monoxide bearing ices. The chemical modifications were monitored on line and in situ via absorption-reflection-absorption Fourier transform infrared spectroscopy as well as in the gas-phase via a quadrupole mass spectrometer. Detected products include two newly formed carbon monoxide isotopomers ((12)C(16)O and (13)C(18)O), carbon dioxide ((12)C(16)O(2), (12)C(18)O(16)O, (12)C(18)O(2), (13)C(16)O(2), (13)C(18)O(16)O, and (13)C(18)O(2)), and dicarbon monoxide ((12)C(13)C(16)O and (13)C(13)C(16)O). Kinetic profiles of carbon monoxide and of carbon dioxide were extracted and fit to derive reaction mechanisms and information on the decomposition of carbon monoxide and on the formation of carbon dioxide in extraterrestrial ice analog samples.
Detection of variable VHE γ-ray emission from the extra-galactic γ-ray binary LMC P3
NASA Astrophysics Data System (ADS)
HESS Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Angüner, E. O.; Arakawa, M.; Armand, C.; Arrieta, M.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Caroff, S.; Carosi, A.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Colafrancesco, S.; Condon, B.; Conrad, J.; Davids, I. D.; Decock, J.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Donath, A.; Drury, L. O.'C.; Dyks, J.; Edwards, T.; Egberts, K.; Emery, G.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Funk, S.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Garrigoux, T.; Gaté, F.; Giavitto, G.; Glawion, D.; Glicenstein, J. F.; Gottschall, D.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Malyshev, D.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Ndiyavala, H.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poireau, V.; Prokhorov, D. A.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Rauth, R.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Rinchiuso, L.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Shiningayamwe, K.; Simoni, R.; Sol, H.; Spanier, F.; Spir-Jacob, M.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Steppa, C.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsirou, M.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zorn, J.; Żywucka, N.
2018-03-01
Context. Recently, the high-energy (HE, 0.1-100 GeV) γ-ray emission from the object LMC P3 in the Large Magellanic Cloud (LMC) has been discovered to be modulated with a 10.3-day period, making it the first extra-galactic γ-ray binary. Aim. This work aims at the detection of very-high-energy (VHE, >100 GeV) γ-ray emission and the search for modulation of the VHE signal with the orbital period of the binary system. Methods: LMC P3 has been observed with the High Energy Stereoscopic System (H.E.S.S.); the acceptance-corrected exposure time is 100 h. The data set has been folded with the known orbital period of the system in order to test for variability of the emission. Results: VHE γ-ray emission is detected with a statistical significance of 6.4 σ. The data clearly show variability which is phase-locked to the orbital period of the system. Periodicity cannot be deduced from the H.E.S.S. data set alone. The orbit-averaged luminosity in the 1-10 TeV energy range is (1.4 ± 0.2) × 1035 erg s-1. A luminosity of (5 ± 1) × 1035 erg s-1 is reached during 20% of the orbit. HE and VHE γ-ray emissions are anti-correlated. LMC P3 is the most luminous γ-ray binary known so far.
Detection of variable VHE γ -ray emission from the extra-galactic γ -ray binary LMC P3
Abdalla, H.; Abramowski, A.; Aharonian, F.; ...
2018-02-01
Context. Recently, the high-energy (HE, 0.1–100 GeV) γ-ray emission from the object LMC P3 in the Large Magellanic Cloud (LMC) has been discovered to be modulated with a 10.3-day period, making it the first extra-galactic γ-ray binary. Aim. This work aims at the detection of very-high-energy (VHE, >100 GeV) γ-ray emission and the search for modulation of the VHE signal with the orbital period of the binary system. Methods. LMC P3 has been observed with the High Energy Stereoscopic System (H.E.S.S.); the acceptance-corrected exposure time is 100 h. The data set has been folded with the known orbital period ofmore » the system in order to test for variability of the emission. Results. VHE γ-ray emission is detected with a statistical significance of 6.4 σ. The data clearly show variability which is phase-locked to the orbital period of the system. Periodicity cannot be deduced from the H.E.S.S. data set alone. The orbit-averaged luminosity in the 1–10 TeV energy range is (1.4 ± 0.2) × 1035 erg s -1. A luminosity of (5 ± 1) × 1035 erg s -1 is reached during 20% of the orbit. HE and VHE γ-ray emissions are anti-correlated. In conclucion, LMC P3 is the most luminous γ-ray binary known so far.« less
Detection of variable VHE γ -ray emission from the extra-galactic γ -ray binary LMC P3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abdalla, H.; Abramowski, A.; Aharonian, F.
Context. Recently, the high-energy (HE, 0.1–100 GeV) γ-ray emission from the object LMC P3 in the Large Magellanic Cloud (LMC) has been discovered to be modulated with a 10.3-day period, making it the first extra-galactic γ-ray binary. Aim. This work aims at the detection of very-high-energy (VHE, >100 GeV) γ-ray emission and the search for modulation of the VHE signal with the orbital period of the binary system. Methods. LMC P3 has been observed with the High Energy Stereoscopic System (H.E.S.S.); the acceptance-corrected exposure time is 100 h. The data set has been folded with the known orbital period ofmore » the system in order to test for variability of the emission. Results. VHE γ-ray emission is detected with a statistical significance of 6.4 σ. The data clearly show variability which is phase-locked to the orbital period of the system. Periodicity cannot be deduced from the H.E.S.S. data set alone. The orbit-averaged luminosity in the 1–10 TeV energy range is (1.4 ± 0.2) × 1035 erg s -1. A luminosity of (5 ± 1) × 1035 erg s -1 is reached during 20% of the orbit. HE and VHE γ-ray emissions are anti-correlated. In conclucion, LMC P3 is the most luminous γ-ray binary known so far.« less
A Collaboration Network Model Of Cytokine-Protein Network
NASA Astrophysics Data System (ADS)
Zou, Sheng-Rong; Zhou, Ta; Peng, Yu-Jing; Guo, Zhong-Wei; Gu, Chang-Gui; He, Da-Ren
2008-03-01
Complex networks provide us a new view for investigation of immune systems. We collect data through STRING database and present a network description with cooperation network model. The cytokine-protein network model we consider is constituted by two kinds of nodes, one is immune cytokine types which can be regarded as collaboration acts, the other one is protein type which can be regarded as collaboration actors. From act degree distribution that can be well described by typical SPL (shifted power law) functions [1], we find that HRAS, TNFRSF13C, S100A8, S100A1, MAPK8, S100A7, LIF, CCL4, CXCL13 are highly collaborated with other proteins. It reveals that these mediators are important in cytokine-protein network to regulate immune activity. Dyad in the collaboration networks can be defined as two proteins and they appear in one cytokine collaboration relationship. The dyad act degree distribution can also be well described by typical SPL functions. [1] Assortativity and act degree distribution of some collaboration networks, Hui Chang, Bei-Bei Su, Yue-Ping Zhou, Daren He, Physica A, 383 (2007) 687-702
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warner, Thomas; Jalilehvand, Farideh
Mercury(II) ions precipitate from aqueous cysteine (H 2Cys) solutions containing H 2Cys/Hg(II) mole ratio ≥ 2.0 as Hg( S-HCys) 2. In absence of additional cysteine, the precipitate dissolves at pH ~12 with the [Hg( S, N-Cys) 2] 2- complex dominating. With excess cysteine (H 2Cys/Hg(II) mole ratio ≥ 4.0), higher complexes form and the precipitate dissolves at lower pH values. Previously, we found that tetrathiolate [Hg( S-Cys) 4] 6- complexes form at pH = 11.0; in this work we extend the investigation to pH values of physiological interest. We examined two series of Hg(II)-cysteine solutions in which C Hg(II) variedmore » between 8 – 9 mM and 80 – 100 mM, respectively, with H 2Cys/Hg(II) mole ratios from 4 to ~20. The solutions were prepared in the pH range 7.1 – 8.8, at the pH at which the initial Hg( S-HCys) 2 precipitate dissolved. The variations in the Hg(II) speciation were followed by 199Hg NMR, X-ray absorption and Raman spectroscopic techniques. Our results show that in the dilute solutions (C Hg(II) = 8 – 9 mM), mixtures of di-, tri- (major) and tetrathiolate complexes exist at moderate cysteine excess (C H2Cys ~ 0.16 M) at pH 7.1. In the more concentrated solutions (C Hg(II) = 80 – 100 mM) with high cysteine excess (C H2Cys > 0.9 M), tetrathiolate [Hg( S-cysteinate) 4] m-6 ( m = 0 – 4) complexes dominate in the pH range 7.3 – 7.8, with lower charge than for the [Hg( S-Cys) 4] 6- complex due to protonation of some ( m) of the amino groups of the coordinated cysteine ligands. In conclusion, the results of this investigation could provide a key to the mechanism of biosorption and accumulation of Hg(II) ions in biological / environmental systems.« less
Gabriel, C; Raptopoulou, C P; Terzis, A; Tangoulis, V; Mateescu, C; Salifoglou, A
2007-04-16
In an attempt to understand the aqueous interactions of Cr(III) with the low-molecular-mass physiological ligand citric acid, the pH-specific synthesis in the binary Cr(III)-citrate system was explored, leading to the complex (NH4)4[Cr(C6H4O7)(C6H5O7)].3H2O (1). 1 crystallizes in the monoclinic space group I2/a, with a = 19.260(10) A, b = 10.006(6) A, c = 23.400(10) A, beta = 100.73(2) degrees , V = 4431(4) A3, and Z = 8. 1 was characterized by elemental analysis and spectroscopic, structural, thermal, and magnetic susceptibility studies. Detailed aqueous speciation studies in the Cr(III)-citrate system suggest the presence of a number of species, among which is the mononuclear [Cr(C6H4O7)(C6H5O7)]4- complex, optimally present around pH approximately 5.5. The structure of 1 reveals a mononuclear octahedral complex of Cr(III) with two citrate ligands bound to it. The two citrate ligands have different deprotonation states, thus signifying the importance of the mixed deprotonation state in the coordination sphere of the Cr(III) species in aqueous speciation. The latter reveals the distribution of numerous species, including 1, for which the collective structural, spectroscopic, and magnetic data point out its physicochemical profile in the solid state and in solution. The importance of the synthetic efforts linked to 1 and the potential ramifications of Cr(III) reactivity toward both low- and high-molecular-mass biotargets are discussed in light of (a) the quest for well-characterized soluble Cr(III) species that could be detected and identified in biologically relevant fluids, (b) ongoing efforts to delineate the aqueous speciation of the Cr(III)-citrate system and its link to biotoxic Cr(III) manifestations, and (c) the synthetic utility of convenient Cr(III) precursors in the synthesis of advanced materials.
Geomorphic Flood Area (GFA): a QGIS tool for a cost-effective delineation of the floodplains
NASA Astrophysics Data System (ADS)
Samela, Caterina; Albano, Raffaele; Sole, Aurelia; Manfreda, Salvatore
2017-04-01
The importance of delineating flood hazard and risk areas at a global scale has been highlighted for many years. However, its complete achievement regularly encounters practical difficulties, above all the lack of data and implementation costs. In conditions of scarce data availability (e.g. ungauged basins, large-scale analyses), a fast and cost-effective floodplain delineation can be carried out using geomorphic methods (e.g., Manfreda et al., 2011; 2014). In particular, an automatic DEM-based procedure has been implemented in an open-source QGIS plugin named Geomorphic Flood Area - tool (GFA - tool). This tool performs a linear binary classification based on the recently proposed Geomorphic Flood Index (GFI), which exhibited high classification accuracy and reliability in several test sites located in Europe, United States and Africa (Manfreda et al., 2015; Samela et al., 2016, 2017; Samela, 2016). The GFA - tool is designed to make available to all users the proposed procedure, that includes a number of operations requiring good geomorphic and GIS competences. It allows computing the GFI through terrain analysis, turning it into a binary classifier, and training it on the base of a standard inundation map derived for a portion of the river basin (a minimum of 2% of the river basin's area is suggested) using detailed methods of analysis (e.g. flood hazard maps produced by emergency management agencies or river basin authorities). Finally, GFA - tool allows to extend the classification outside the calibration area to delineate the flood-prone areas across the entire river basin. The full analysis has been implemented in this plugin with a user-friendly interface that should make it easy to all user to apply the approach and produce the desired results. Keywords: flood susceptibility; data scarce environments; geomorphic flood index; linear binary classification; Digital elevation models (DEMs). References Manfreda, S., Di Leo, M., Sole, A., (2011). Detection of Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, 16(10), 781-790. Manfreda, S., Nardi, F., Samela, C., Grimaldi, S., Taramasso, A. C., Roth, G., & Sole, A. (2014). Investigation on the Use of Geomorphic Approaches for the Delineation of Flood Prone Areas, Journal of Hydrology, 517, 863-876. Manfreda, S., Samela, C., Gioia, A., Consoli, G., Iacobellis, V., Giuzio, L., & Sole, A. (2015). Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models. Natural Hazards, Vol. 79 (2), pp 735-754. Samela, C. (2016), 100-year flood susceptibility maps for the continental U.S. derived with a geomorphic method. University of Basilicata. Dataset. Samela, C., Manfreda, S., Paola, F. D., Giugni, M., Sole, A., & Fiorentino, M. (2016). DEM-Based Approaches for the Delineation of Flood-Prone Areas in an Ungauged Basin in Africa. Journal of Hydrologic Engineering, 21(2), 1-10. Samela, C., Troy, T.J., Manfreda, S. (2017). Geomorphic classifiers for flood-prone areas delineation for data-scarce environments, Advances in Water Resources (under review).
Black Hole-Neutron Star Mergers as Central Engines of Gamma-Ray Bursts.
Janka; Eberl; Ruffert; Fryer
1999-12-10
Hydrodynamic simulations of the merger of stellar mass black hole-neutron star binaries are compared with mergers of binary neutron stars. The simulations are Newtonian but take into account the emission and back-reaction of gravitational waves. The use of a physical nuclear equation of state allows us to include the effects of neutrino emission. For low neutron star-to-black hole mass ratios, the neutron star transfers mass to the black hole during a few cycles of orbital decay and subsequent widening before finally being disrupted, whereas for ratios near unity the neutron star is destroyed during its first approach. A gas mass between approximately 0.3 and approximately 0.7 M middle dot in circle is left in an accretion torus around the black hole and radiates neutrinos at a luminosity of several times 1053 ergs s-1 during an estimated accretion timescale of about 0.1 s. The emitted neutrinos and antineutrinos annihilate into e+/- pairs with efficiencies of 1%-3% and rates of up to approximately 2x1052 ergs s-1, thus depositing an energy Enunu&d1; less, similar1051 ergs above the poles of the black hole in a region that contains less than 10-5 M middle dot in circle of baryonic matter. This could allow for relativistic expansion with Lorentz factors around 100 and is sufficient to explain apparent burst luminosities Lgamma approximately Enunu&d1;&solm0;&parl0;fOmegatgamma&parr0; up to several times 1053 ergs s-1 for burst durations tgamma approximately 0.1-1 s, if the gamma emission is collimated in two moderately focused jets in a fraction fOmega=2deltaOmega&solm0;&parl0;4pi&parr0; approximately 1&solm0;100-(1/10) of the sky.
LDPC-coded orbital angular momentum (OAM) modulation for free-space optical communication.
Djordjevic, Ivan B; Arabaci, Murat
2010-11-22
An orbital angular momentum (OAM) based LDPC-coded modulation scheme suitable for use in FSO communication is proposed. We demonstrate that the proposed scheme can operate under strong atmospheric turbulence regime and enable 100 Gb/s optical transmission while employing 10 Gb/s components. Both binary and nonbinary LDPC-coded OAM modulations are studied. In addition to providing better BER performance, the nonbinary LDPC-coded modulation reduces overall decoder complexity and latency. The nonbinary LDPC-coded OAM modulation provides a net coding gain of 9.3 dB at the BER of 10(-8). The maximum-ratio combining scheme outperforms the corresponding equal-gain combining scheme by almost 2.5 dB.
NASA Astrophysics Data System (ADS)
Jagadeesh, M.; Rashmi, H. K.; Subba Rao, Y.; Sreenath Reddy, A.; Prathima, B.; Uma Maheswari Devi, P.; Reddy, A. Varada
2013-11-01
A new cis-palladium(II)diaqua(3,4-difluoroacetophenonethiosemicarbazone complex (Pd(II) complex) is synthesized using 3,4-difluoroacetophenonethiosemicarbazone(L). The L and its Pd(II) complex are characterized and confirmed by elemental analyses, electrochemical analyses, FT-IR, FT-Raman, UV-Vis, HRMS and LC-MS techniques. Ligand L is further characterized by 1H, 13C and 19F NMR spectroscopy. The crystal structure of L is unambiguously characterized by single X-ray crystallography. The ligand (L) belongs to monoclinic system with P2(1)/C space group and the unit cell parameters are a(Å) = 9.1144(7), b(Å) = 13.7928(7), c(Å) = 8.4174(5), α(°) = 90, β(°) = 100.715, γ(°) = 90 and volume V(A3) = 1039.73(11). The Raman bands observed for the L and its Pd(II) complex are in good agreement with the FT-IR spectral data. The Pd(II) complex is found to be highly efficient in inhibiting the growth of human pathogens like Salmonella typhimurium and Klebsiella pneumonia with MIC value 10.0 μg/mL whose inhibition zones are almost comparable with the standard antibiotic. The synthesized compounds have shown antiproliferative activity against the human breast cancer cell lines MDA-MB231 by intermitting the regular pathway of ribonucleotidereductase.
Lead(II) binding to the chelating agent d-penicillamine in aqueous solution
Sisombath, Natalie S.; Jalilehvand, Farideh; Schell, Adam C.; ...
2014-11-11
Here, a spectroscopic investigation of the complexes formed between the Pb(II) ion and d-penicillamine (H 2Pen), a chelating agent used in the treatment of lead poisoning, was carried out on two sets of alkaline aqueous solutions with C Pb(II) ≈ 10 and 100 mM, varying the H 2Pen/Pb(II) molar ratio (2.0, 3.0, 4.0, 10.0). Ultraviolet–visible (UV-vis) spectra of the 10 mM Pb(II) solutions consistently showed an absorption peak at 298 nm for S – → Pb(II) ligand-to-metal charge-transfer. The downfield 13C NMR chemical shift for the penicillamine COO – group confirmed Pb(II) coordination. The 207Pb NMR chemical shifts were confinedmore » to a narrow range between 1806 ppm and 1873 ppm for all Pb(II)-penicillamine solutions, indicating only small variations in the speciation, even in large penicillamine excess. Those chemical shifts are considerably deshielded, relative to the solid-state 207Pb NMR isotropic chemical shift of 909 ppm obtained for crystalline penicillaminatolead(II) with Pb(S,N,O-Pen) coordination. The Pb L III-edge extended X-ray absorption fine structure (EXAFS) spectra obtained for these solutions were well-modeled with two Pb–S and two Pb-(N/O) bonds with mean distances 2.64 ± 0.04 Å and 2.45 ± 0.04 Å, respectively. The combined spectroscopic results, reporting δ( 207Pb) ≈ 1870 ppm and λ max ≈ 298 nm for a Pb IIS 2NO site, are consistent with a dominating 1:2 lead(II):penicillamine complex with [Pb(S,N,O-Pen)(S-H nPen)] 2–n (n = 0–1) coordination in alkaline solutions, and provide useful structural information on how penicillamine can function as an antidote against lead toxicity in vivo.« less
Ganji, Nirmala; Chityala, Vijay Kumar; Marri, Pradeep Kumar; Aveli, Rambabu; Narendrula, Vamsikrishna; Daravath, Sreenu; Shivaraj
2017-10-01
Two new series of binary metal complexes [M(L 1 ) 2 ] and [M(L 2 ) 2 ] where, M=Cu(II), Ni(II) & Co(II) and L 1 =4-((3,4-dimethylisoxazol-5-ylimino)methyl)benzene-1,3-diol; L 2 =2-((3,4-dimethylisoxazol-5-ylimino)methyl)-5-methoxyphenol were synthesized and characterized by elemental analysis, 1 H NMR, 13 C NMR, FT-IR, ESI mass, UV-Visible, magnetic moment, ESR, SEM and powder XRD studies. Based on these results, a square planar geometry is assigned for all the metal complexes where the Schiff base acts as uninegatively charged bidentate chelating agent via the hydroxyl oxygen and azomethine nitrogen atoms. DNA binding studies of all the complexes with calf thymus DNA have been comprehensively investigated using electronic absorption spectroscopy, fluorescence quenching and viscosity studies. The oxidative and photo cleavage affinity of metal complexes towards supercoiled pBR322 DNA has been ascertained by agarose gel electrophoresis assay. From the results, it is observed that all the metal complexes bind effectively to CT-DNA via an intercalative mode of binding and also cleave pBR322 DNA in a promising manner. Further the Cu(II) complexes have shown better binding and cleavage properties towards DNA. The antimicrobial activities of the Schiff bases and their metal complexes were studied on bacterial and fungal strains and the results denoted that the complexes are more potent than their Schiff base ligands. Copyright © 2017 Elsevier B.V. All rights reserved.
Carbonate Complexation of Mn2+ in Aqueous Phase
Dasgupta, Jyotishman; Tyryshkin, Alexei M.; Kozlov, Yuri N.; Klimov, Vyacheslav V.; Dismukes, G. Charles
2008-01-01
The chemical speciation of Mn2+ within cells is critical for its transport, availability and redox properties. Herein we investigate the redox behavior and complexation equilibria of Mn2+ in aqueous solutions of bicarbonate by voltametry and electron paramagnetic resonance (EPR) spectroscopy, and discuss the implications for the uptake of Mn2+ by mangano-cluster enzymes like photosystem II (PSII). Both the electrochemical reduction of Mn2+ to Mn0 at an Hg electrode and EPR (in the absence of a polarizing electrode), revealed formation of 1:1 and 1:2 Mn-(bi)carbonate complexes as a function of Mn2+ and bicarbonate concentrations. Pulsed EPR spectroscopy, including ENDOR, ESEEM and 2D-HYSCORE, were used to probe the hyperfine couplings to 1H and 13C nuclei of the ligand(s) bound to Mn2+. For the 1:2 complex the complete 13C hyperfine tensor for one of the (bi)carbonate ligands was determined and it was established that this ligand coordinates to Mn2+ in bidentate mode with 13C-Mn distance of 2.85 ± 0.1 Å. The second (bi)carbonate ligand in the 1:2 complex coordinates possibly in monodentate mode, which is structurally less defined, and its 13C signal is broad and unobservable. 1H ENDOR reveals that 1-2 water ligands are lost upon binding of one bicarbonate ion in the 1:1 complex while 3-4 water ligands are lost upon forming the 1:2 complex. Thus, we deduce that the dominant species above 0.1 M bicarbonate concentration is the 1:2 complex, [Mn(CO3)(HCO3)(OH2)3]-. PMID:16526753
Gabriel, C; Kaliva, M; Venetis, J; Baran, P; Rodriguez-Escudero, I; Voyiatzis, G; Zervou, M; Salifoglou, A
2009-01-19
Vanadium participation in cellular events entails in-depth comprehension of its soluble and bioavailable forms bearing physiological ligands in aqueous distributions of binary and ternary systems. Poised to understand the ternary V(V)-H(2)O(2)-amino acid interactions relevant to that metal ion's biological role, we have launched synthetic efforts involving the physiological ligands glycine and H(2)O(2). In a pH-specific fashion, V(2)O(5), glycine, and H(2)O(2) reacted and afforded the unusual complexes (H(3)O)(2)[V(2)(O)(2)(mu(2):eta(2):eta(1)-O(2))(2)(eta(2)-O(2))(2)(C(2)H(5)NO(2))] x 5/4 H(2)O (1) and K(2)[V(2)(O)(2)(mu(2):eta(2):eta(1)-O(2))(2)(eta(2)-O(2))(2)(C(2)H(5)NO(2))] x H(2)O (2). 1 crystallizes in the triclinic space group P1, with a = 7.805(4) A, b = 8.134(5) A, c = 12.010(7) A, alpha = 72.298(9) degrees, beta = 72.991(9) degrees, gamma = 64.111(9) degrees, V = 641.9(6) A(3), and Z = 2. 2 crystallizes in the triclinic space group P1, with a = 7.6766(9) A, b = 7.9534(9) A, c = 11.7494(13) A, alpha = 71.768(2) degrees, beta = 73.233(2) degrees, gamma = 65.660(2) degrees, V = 610.15(12) A(3), and Z = 2. Both complexes 1 and 2 were characterized by UV/visible, LC-MS, FT-IR, Raman, NMR spectroscopy, cyclic voltammetry, and X-ray crystallography. The structures of 1 and 2 reveal the presence of unusual ternary dinuclear vanadium-tetraperoxo-glycine complexes containing [(V(V)=O)(O(2))(2)](-) units interacting through long V-O bonds and an effective glycinate bridge. The latter ligand is present in the dianionic assembly as a bidentate moiety spanning both V(V) centers in a zwitterionic form. The collective physicochemical properties of the two ternary species 1 and 2 project the chemical role of the low molecular mass biosubstrate glycine in binding V(V)-diperoxo units, thereby stabilizing a dinuclear V(V)-tetraperoxo dianion. Structural comparisons of the anions in 1 and 2 with other known dinuclear V(V)-tetraperoxo binary anionic species provide insight into the chemical reactivity of V(V)-diperoxo species in key cellular events such as insulin mimesis and antitumorigenicity, potentially modulated by the presence of glycinate and hydrogen peroxide.
NASA Astrophysics Data System (ADS)
Jagadeesh, M.; Kalangi, Suresh K.; Sivarama Krishna, L.; Reddy, A. Varada
2014-01-01
Copper(II) and nickel(II) complexes of two different halogen substituted thiosemicarbazone ligands were synthesized. The ligands 3,4-difluoroacetophenone thiosemicarbazone (1) and 2-bromo-4'-chloroacetophenone thiosemicarbazone (2) were characterized and confirmed spectroscopically by FT-IR, FT-Raman, UV-vis and fluorescence spectral analysis, while the respective copper(II) complexes [Cu(C9H9N3F2S)2Cl2] (1a), [Cu(C9H9N3ClBrS)2Cl2] (2a) and nickel(II) complexes [Ni(C9H9N3F2S)2] (1b), [Ni(C9H9N3ClBrS)2] (2b) were characterized by FT-IR, UV-vis and electron paramagnetic spectroscopy (EPR). The EPR spectra of the Cu(II) complexes provided the rhombic octahedral and axial symmetry of the complexes 1a and 2a respectively. For the complex 1a, the g values calculated as g1 = 2.1228, g2 = 2.0706 and g3 = 2.001 between 2900 and 3300 G. While for the complex 2a, a set of two resonance absorptions were observed. The synthesized compounds were tested for antitumor activity and showed that the ability to kill liver cancer cells significantly. Out of all the synthesized compounds, copper(II) complexes 1a and 2a showed high cytotoxic effect on liver cancer cells with 67.51% and 42.77% of cytotoxicity respectively at 100 μM.
Dharmaraja, Jeyaprakash; Subbaraj, Paramasivam; Esakkidurai, Thirugnanasamy; Shobana, Sutha; Raji, Saravanan
2014-01-01
Mixed ligand complexation of 2-aminobenzamide (2AB) as ligand [L] with Zn(II) in the presence of some bio-relevant amino acid constituents like glycine (gly), L-alanine (ala), L-valine (val) and L-phenylalanine (phe) as ligand [B] have been investigated using pH-metric measurements with a combined pH electrode at different temperatures (300, 310, 320 and 330 ± 0.1 K) in 50% (v/v) ethanol-water mixture containing I = 0.15 M NaClO(4) as supporting electrolyte. Computer assisted analysis of the experimental titration data showed the presence of ZnLB and ZnLB2 species as mixed ligand complexes in addition to various binary species. In ZnLB/ZnLB(2) species, both primary and secondary ligands act as bidentate to form a stable six, five membered chelate ring. The calculated stabilization parameter Deltalog K, log X, log X' and % R.S. values clearly show the mixed ligand complexes have higher stabilities than their binary. Thermodynamic parameters DeltaG, DeltaH and DeltaS have been derived from the temperature dependence of the stability constants. The complexation behavior of ZnLB species has been studied by means of electronic spectra. The percentage distribution of various binary and mixed ligand species of each type of the complexes in solution depending on pH and the ratio of Zn(II) to 2-aminobenzamide/amino acid of the systems.
Finotello, Alexia; Bara, Jason E; Narayan, Suguna; Camper, Dean; Noble, Richard D
2008-02-28
This study focuses on the solubility behaviors of CO2, CH4, and N2 gases in binary mixtures of imidazolium-based room-temperature ionic liquids (RTILs) using 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][Tf2N]) and 1-ethyl-3-methylimidazolium tetrafluoroborate ([C2mim][BF4]) at 40 degrees C and low pressures (approximately 1 atm). The mixtures tested were 0, 25, 50, 75, 90, 95, and 100 mol % [C2mim][BF4] in [C2mim][Tf2N]. Results show that regular solution theory (RST) can be used to describe the gas solubility and selectivity behaviors in RTIL mixtures using an average mixture solubility parameter or an average measured mixture molar volume. Interestingly, the solubility selectivity, defined as the ratio of gas mole fractions in the RTIL mixture, of CO2 with N2 or CH4 in pure [C2mim][BF4] can be enhanced by adding 5 mol % [C2mim][Tf2N].
NASA Astrophysics Data System (ADS)
Dijkstra, P.; Fairbanks, D.; Miller, E.; Salpas, E.; Hagerty, S.
2013-12-01
Understanding the mechanisms regulating C cycling is hindered by our inability to directly observe and measure the biochemical processes of glycolysis, pentose phosphate pathway, and TCA cycle in intact and complex microbial communities. Position-specific 13C labeled metabolic tracer probing is proposed as a new way to study microbial community energy production, biosynthesis, C use efficiency (the proportion of substrate incorporated into microbial biomass), and enables the quantification of C fluxes through the central C metabolic network processes (Dijkstra et al 2011a,b). We determined the 13CO2 production from U-13C, 1-13C, 2-13C, 3-13C, 4-13C, 5-13C, and 6-13C labeled glucose and 1-13C and 2,3-13C pyruvate in parallel incubations in three soils along an elevation gradient. Qualitative and quantitative interpretation of the results indicate a high pentose phosphate pathway activity in soils. Agreement between modeled and measured CO2 production rates for the six C-atoms of 13C-labeled glucose indicate that the metabolic model used is appropriate for soil community processes, but that improvements can be made. These labeling and modeling techniques may improve our ability to analyze the biochemistry and (eco)physiology of intact microbial communities. Dijkstra, P., Blankinship, J.C., Selmants, P.C., Hart, S.C., Koch, G.W., Schwartz, E., Hungate, B.A., 2011a. Probing C flux patterns of soil microbial metabolic networks using parallel position-specific tracer labeling. Soil Biology & Biochemistry 43, 126-132. Dijkstra, P., Dalder, J.J., Selmants, P.C., Hart, S.C., Koch, G.W., Schwartz, E., Hungate, B.A., 2011b. Modeling soil metabolic processes using isotopologue pairs of position-specific 13C-labeled glucose and pyruvate. Soil Biology & Biochemistry 43, 1848-1857.
Transport and imaging of brute-force 13C hyperpolarization
NASA Astrophysics Data System (ADS)
Hirsch, Matthew L.; Smith, Bryce A.; Mattingly, Mark; Goloshevsky, Artem G.; Rosay, Melanie; Kempf, James G.
2015-12-01
We demonstrate transport of hyperpolarized frozen 1-13C pyruvic acid from its site of production to a nearby facility, where a time series of 13C images was acquired from the aqueous dissolution product. Transportability is tied to the hyperpolarization (HP) method we employ, which omits radical electron species used in other approaches that would otherwise relax away the HP before reaching the imaging center. In particular, we attained 13C HP by 'brute-force', i.e., using only low temperature and high-field (e.g., T < ∼2 K and B ∼ 14 T) to pre-polarize protons to a large Boltzmann value (∼0.4% 1H polarization). After polarizing the neat, frozen sample, ejection quickly (<1 s) passed it through a low field (B < 100 G) to establish the 1H pre-polarization spin temperature on 13C via the process known as low-field thermal mixing (yielding ∼0.1% 13C polarization). By avoiding polarization agents (a.k.a. relaxation agents) that are needed to hyperpolarize by the competing method of dissolution dynamic nuclear polarization (d-DNP), the 13C relaxation time was sufficient to transport the sample for ∼10 min before finally dissolving in warm water and obtaining a 13C image of the hyperpolarized, dilute, aqueous product (∼0.01% 13C polarization, a >100-fold gain over thermal signals in the 1 T scanner). An annealing step, prior to polarizing the sample, was also key for increasing T1 ∼ 30-fold during transport. In that time, HP was maintained using only modest cryogenics and field (T ∼ 60 K and B = 1.3 T), for T1(13C) near 5 min. Much greater time and distance (with much smaller losses) may be covered using more-complete annealing and only slight improvements on transport conditions (e.g., yielding T1 ∼ 5 h at 30 K, 2 T), whereas even intercity transfer is possible (T1 > 20 h) at reasonable conditions of 6 K and 2 T. Finally, it is possible to increase the overall enhancement near d-DNP levels (i.e., 102-fold more) by polarizing below 100 mK, where nanoparticle agents are known to hasten T1 buildup by 100-fold, and to yield very little impact on T1 losses at temperatures relevant to transport.
Clostridium and bacillus binary enterotoxins: bad for the bowels, and eukaryotic being.
Stiles, Bradley G; Pradhan, Kisha; Fleming, Jodie M; Samy, Ramar Perumal; Barth, Holger; Popoff, Michel R
2014-09-05
Some pathogenic spore-forming bacilli employ a binary protein mechanism for intoxicating the intestinal tracts of insects, animals, and humans. These Gram-positive bacteria and their toxins include Clostridium botulinum (C2 toxin), Clostridium difficile (C. difficile toxin or CDT), Clostridium perfringens (ι-toxin and binary enterotoxin, or BEC), Clostridium spiroforme (C. spiroforme toxin or CST), as well as Bacillus cereus (vegetative insecticidal protein or VIP). These gut-acting proteins form an AB complex composed of ADP-ribosyl transferase (A) and cell-binding (B) components that intoxicate cells via receptor-mediated endocytosis and endosomal trafficking. Once inside the cytosol, the A components inhibit normal cell functions by mono-ADP-ribosylation of globular actin, which induces cytoskeletal disarray and death. Important aspects of each bacterium and binary enterotoxin will be highlighted in this review, with particular focus upon the disease process involving the biochemistry and modes of action for each toxin.
Clostridium and Bacillus Binary Enterotoxins: Bad for the Bowels, and Eukaryotic Being
Stiles, Bradley G.; Pradhan, Kisha; Fleming, Jodie M.; Samy, Ramar Perumal; Barth, Holger; Popoff, Michel R.
2014-01-01
Some pathogenic spore-forming bacilli employ a binary protein mechanism for intoxicating the intestinal tracts of insects, animals, and humans. These Gram-positive bacteria and their toxins include Clostridium botulinum (C2 toxin), Clostridium difficile (C. difficile toxin or CDT), Clostridium perfringens (ι-toxin and binary enterotoxin, or BEC), Clostridium spiroforme (C. spiroforme toxin or CST), as well as Bacillus cereus (vegetative insecticidal protein or VIP). These gut-acting proteins form an AB complex composed of ADP-ribosyl transferase (A) and cell-binding (B) components that intoxicate cells via receptor-mediated endocytosis and endosomal trafficking. Once inside the cytosol, the A components inhibit normal cell functions by mono-ADP-ribosylation of globular actin, which induces cytoskeletal disarray and death. Important aspects of each bacterium and binary enterotoxin will be highlighted in this review, with particular focus upon the disease process involving the biochemistry and modes of action for each toxin. PMID:25198129
Shimamoto, Seiko; Kubota, Yasuo; Yamaguchi, Fuminori; Tokumitsu, Hiroshi; Kobayashi, Ryoji
2013-01-01
The U-box E3 ubiquitin ligase CHIP (C terminus of Hsc70-interacting protein) binds Hsp90 and/or Hsp70 via its tetratricopeptide repeat (TPR), facilitating ubiquitination of the chaperone-bound client proteins. Mechanisms that regulate the activity of CHIP are, at present, poorly understood. We previously reported that Ca2+/S100 proteins directly associate with the TPR proteins, such as Hsp70/Hsp90-organizing protein (Hop), kinesin light chain, Tom70, FKBP52, CyP40, and protein phosphatase 5 (PP5), leading to the dissociation of the interactions of the TPR proteins with their target proteins. Therefore, we have hypothesized that Ca2+/S100 proteins can interact with CHIP and regulate its function. GST pulldown assays indicated that Ca2+/S100A2 and S100P bind to the TPR domain and lead to interference with the interactions of CHIP with Hsp70, Hsp90, HSF1, and Smad1. In vitro ubiquitination assays indicated that Ca2+/S100A2 and S100P are efficient and specific inhibitors of CHIP-mediated ubiquitination of Hsp70, Hsp90, HSF1, and Smad1. Overexpression of S100A2 and S100P suppressed CHIP-chaperone complex-dependent mutant p53 ubiquitination and degradation in Hep3B cells. The association of the S100 proteins with CHIP provides a Ca2+-dependent regulatory mechanism for the ubiquitination and degradation of intracellular proteins by the CHIP-proteasome pathway. PMID:23344957
Deriving Link Travel-Time Distributions via Stochastic Speed Processes
2004-02-01
general, an exact expression for the inverse transform is available when Equation (9) is a vector of rational functions in both of the complex variables...Otherwise, recovery of the original function is accom- plished through the inverse transform f t= 1 2(j ∫ c+j c−j estf ∗s ds (13) which is usually...given by f x t = f ∗s1 s2 = ∫ 0 ∫ 0 e−s1x+s2tf x t dx dt (14) with inverse transform f x t = 1 4(2 ∫ c1+j c1−j ∫ c2+j c2−j e
Formation of Hg(II) tetrathiolate complexes with cysteine at neutral pH
Warner, Thomas; Jalilehvand, Farideh
2016-01-04
Mercury(II) ions precipitate from aqueous cysteine (H 2Cys) solutions containing H 2Cys/Hg(II) mole ratio ≥ 2.0 as Hg( S-HCys) 2. In absence of additional cysteine, the precipitate dissolves at pH ~12 with the [Hg( S, N-Cys) 2] 2- complex dominating. With excess cysteine (H 2Cys/Hg(II) mole ratio ≥ 4.0), higher complexes form and the precipitate dissolves at lower pH values. Previously, we found that tetrathiolate [Hg( S-Cys) 4] 6- complexes form at pH = 11.0; in this work we extend the investigation to pH values of physiological interest. We examined two series of Hg(II)-cysteine solutions in which C Hg(II) variedmore » between 8 – 9 mM and 80 – 100 mM, respectively, with H 2Cys/Hg(II) mole ratios from 4 to ~20. The solutions were prepared in the pH range 7.1 – 8.8, at the pH at which the initial Hg( S-HCys) 2 precipitate dissolved. The variations in the Hg(II) speciation were followed by 199Hg NMR, X-ray absorption and Raman spectroscopic techniques. Our results show that in the dilute solutions (C Hg(II) = 8 – 9 mM), mixtures of di-, tri- (major) and tetrathiolate complexes exist at moderate cysteine excess (C H2Cys ~ 0.16 M) at pH 7.1. In the more concentrated solutions (C Hg(II) = 80 – 100 mM) with high cysteine excess (C H2Cys > 0.9 M), tetrathiolate [Hg( S-cysteinate) 4] m-6 ( m = 0 – 4) complexes dominate in the pH range 7.3 – 7.8, with lower charge than for the [Hg( S-Cys) 4] 6- complex due to protonation of some ( m) of the amino groups of the coordinated cysteine ligands. In conclusion, the results of this investigation could provide a key to the mechanism of biosorption and accumulation of Hg(II) ions in biological / environmental systems.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henni, A.; Maham, Y.; Tontiwachwuthikul, P.
2000-04-01
Recent studies done on the absorption and desorption of acid gases (CO{sub 2}, H{sub 2}S) from natural gas, petroleum, and ammonia synthesis streams have shown that aqueous solutions of N-methyldiethanolamine (MDEA) can be used effectively for the selective removal of H{sub 2}S. This paper reports the measured values of the density and viscosity of binary mixtures of N-methyldiethanolamine (MDEA) and triethylene glycol monomethyl ether (TEGMME) at five temperatures in the range 25 C to 70 C over the whole concentration range. The authors also report the density and viscosity of the binary mixture MDEA + ethanol at 40 C. Themore » results are compared with data for aqueous mixtures and other alkanolamines when these are available. The derived excess molar volumes and viscosity deviations were correlated as a function of composition. The Grunberg-Nissan interaction energy constants are also reported.« less
Deguchi, A; Tomita, T; Ohto, U; Takemura, K; Kitao, A; Akashi-Takamura, S; Miyake, K; Maru, Y
2016-03-17
S100A8/A9 is a major component of the acute phase of inflammation, and appears to regulate cell proliferation, redox regulation and chemotaxis. We previously reported that S100A8/S100A9 are upregulated in the premetastatic lung. However, the detailed mechanisms by which S100A8 contributes to tumor progression have not been elucidated. In this study, we investigated the TLR4/MD-2 dependency by S100A8 on tumor progression. We found that S100A8 (2-89) peptide stimulated cell migration in a manner dependent on TLR4, MD-2 and MyD88. The S100A8 (2-89) peptide also activated p38 and NF-κB in TLR4-dependent manner. The peptide induced the upregulation of both IL-6 and Ccl2 in peritoneal macrophages obtained from wild-type mice, but not TLR4-deficient mice. We then investigated the responsible region of S100A8 for TLR4/MD-2 binding by a binding assay, and found that C-terminal region of S100A8 binds to TLR4/MD-2 complex. To further evaluate the TLR4 dependency on tumor microenvironment, Lewis lung carcinoma-bearing mice were treated with Eritoran, an antagonist of TLR4/MD-2 complex. We found that both tumor volume and pulmonary recruitment of myeloid-derived suppressor cells were reduced with the treatment of Eritoran for five consecutive days. Eritoran reduced the development of tumor vasculature, and increased tumor-infiltration of CD8(+) T-cells. Taken together, S100A8 appears to play a crucial role in the activation of the TLR4/MD-2 pathway and the promotion of a tumor growth-enhancing immune microenvironment.
A ternary metal binding site in the C2 domain of phosphoinositide-specific phospholipase C-delta1.
Essen, L O; Perisic, O; Lynch, D E; Katan, M; Williams, R L
1997-03-11
We have determined the crystal structures of complexes of phosphoinositide-specific phospholipase C-delta1 from rat with calcium, barium, and lanthanum at 2.5-2.6 A resolution. Binding of these metal ions is observed in the active site of the catalytic TIM barrel and in the calcium binding region (CBR) of the C2 domain. The C2 domain of PLC-delta1 is a circularly permuted topological variant (P-variant) of the synaptotagmin I C2A domain (S-variant). On the basis of sequence analysis, we propose that both the S-variant and P-variant topologies are present among other C2 domains. Multiple adjacent binding sites in the C2 domain were observed for calcium and the other metal/enzyme complexes. The maximum number of binding sites observed was for the calcium analogue lanthanum. This complex shows an array-like binding of three lanthanum ions (sites I-III) in a crevice on one end of the C2 beta-sandwich. Residues involved in metal binding are contained in three loops, CBR1, CBR2, and CBR3. Sites I and II are maintained in the calcium and barium complexes, whereas sites II and III coincide with a binary calcium binding site in the C2A domain of synaptotagmin I. Several conformers for CBR1 are observed. The conformation of CBR1 does not appear to be strictly dependent on metal binding; however, metal binding may stabilize certain conformers. No significant structural changes are observed for CBR2 or CBR3. The surface of this ternary binding site provides a cluster of freely accessible liganding positions for putative phospholipid ligands of the C2 domain. It may be that the ternary metal binding site is also a feature of calcium-dependent phospholipid binding in solution. A ternary metal binding site might be a conserved feature among C2 domains that contain the critical calcium ligands in their CBR's. The high cooperativity of calcium-mediated lipid binding by C2 domains described previously is explained by this novel type of calcium binding site.
Albadarin, Ahmad B; Mangwandi, Chirangano
2015-12-01
The biosorption process of anionic dye Alizarin Red S (ARS) and cationic dye methylene blue (MB) as a function of contact time, initial concentration and solution pH onto olive stone (OS) biomass has been investigated. Equilibrium biosorption isotherms in single and binary systems and kinetics in batch mode were also examined. The kinetic data of the two dyes were better described by the pseudo second-order model. At low concentration, ARS dye appeared to follow a two-step diffusion process, while MB dye followed a three-step diffusion process. The biosorption experimental data for ARS and MB dyes were well suited to the Redlich-Peterson isotherm. The maximum biosorption of ARS dye, qmax = 16.10 mg/g, was obtained at pH 3.28 and the maximum biosorption of MB dye, qmax = 13.20 mg/g, was observed at basic pH values. In the binary system, it was indicated that the MB dye diffuses firstly inside the biosorbent particle and occupies the biosorption sites forming a monodentate complex and then the ARS dye enters and can only bind to untaken sites; forms a tridentate complex with OS active sites. Copyright © 2015 Elsevier Ltd. All rights reserved.
Rasheed, Fahad; Dreyer, Erwin; Richard, Béatrice; Brignolas, Franck; Montpied, Pierre; Le Thiec, Didier
2013-01-01
(13) C discrimination between atmosphere and bulk leaf matter (Δ(13) C(lb) ) is frequently used as a proxy for transpiration efficiency (TE). Nevertheless, its relevance is challenged due to: (1) potential deviations from the theoretical discrimination model, and (2) complex time integration and upscaling from leaf to whole plant. Six hybrid genotypes of Populus deltoides×nigra genotypes were grown in climate chambers and tested for whole-plant TE (i.e. accumulated biomass/water transpired). Net CO(2) assimilation rates (A) and stomatal conductance (g(s) ) were recorded in parallel to: (1) (13) C in leaf bulk material (δ(13) C(lb) ) and in soluble sugars (δ(13) C(ss) ) and (2) (18) O in leaf water and bulk leaf material. Genotypic means of δ(13) C(lb) and δ(13) C(ss) were tightly correlated. Discrimination between atmosphere and soluble sugars was correlated with daily intrinsic TE at leaf level (daily mean A/g(s) ), and with whole-plant TE. Finally, g(s) was positively correlated to (18) O enrichment of bulk matter or water of leaves at individual level, but not at genotype level. We conclude that Δ(13) C(lb) captures efficiently the genetic variability of whole-plant TE in poplar. Nevertheless, scaling from leaf level to whole-plant TE requires to take into account water losses and respiration independent of photosynthesis, which remain poorly documented. © 2012 Blackwell Publishing Ltd.
PRANC: Program for Analyzing Nonlinear Circuits.
1980-05-01
NAMES: so2 9 C ALL VARIlABLE NAMIES AND ARRAYS AS DEFINED IN SUB-PROGRAM *92P s0 204 c * zot. . Gzp 100 C * CZp 110 C****~*******.****.********a...G2P 120 c GZP 130 COMPLEX CHAT(M?.I),E TCS1),X(iS1),EUALS(l) GZP 140 DIMENSION NPORT(.1). EM:AT(M.1) CZP 150 COMMON /ENOS/ NCOP...IvJ) GZP 240 104 CONTINUE- CZP 250 RE -1 URN GEP 260 C, G-P 270 10S FORMAT (1H1,29HOPEN CIRCUIT IMPEDANCE MATRIX) G.Zp 280 103 FORNIAT (lX,2H3-(#,4
NASA Astrophysics Data System (ADS)
Peebles, Rebecca A.; Peebles, Sean A.; Christenholz, Cori L.; Ernst, Anthony A.; Dhahir, Yasser J.
2013-06-01
The spectra of the CH_2F_2\\cdotspropyne and CH_2ClF\\cdotspropyne complexes have been studied by chirped-pulse and resonant cavity Fourier-transform microwave spectroscopy and by ab initio calculations at the MP2/6-311++G(2d,2p) level. Both complexes contain C-H\\cdotsπ contacts, with the halogen atoms angled towards the methyl group end of the propyne. While CH_2F_2\\cdotspropyne has C_s symmetry, CH_2ClF\\cdotspropyne has C_1 symmetry, with the fluorine and chlorine atoms straddling the propyne. Investigation of four single ^{13}C and the DC≡CCH_3 isotopologues in CH_2F_2\\cdotspropyne has allowed a detailed structural determination, while only the ^{35}Cl and ^{37}Cl isotopologues have so far been assigned for CH_2ClF\\cdotspropyne. Experimental data will be compared with ab initio results and with the analogous acetylene complexes, both of which have C_s symmetry structures, with double C-H\\cdotsπ interactions.
NASA Astrophysics Data System (ADS)
Gjersing, Erica Lee
The techniques of Nuclear Magnetic Resonance (NMR) and Raman spectroscopy have been employed to study structure and dynamics in Ge-Se, Ge/As-Te, and As-S binary and complex Ge-As-Te and P-As-S ternary chalcogenide glasses. Structural studies were conducted on Ge-Se glasses and on binary Ge/As-Te and ternary Ge-As-Te systems. The structure of the GexSe100-x glass series, with 5≤x≤33, is investigated with 77Se Magic Angle Spinning (MAS) NMR and then compared with three different proposed structural models. For the binary Ge-Te and As-Te and ternary Ge-As-Te glass systems the structure is studied using Raman spectroscopy and correlated with physical properties such as molar volume, viscosity, optical band gap and thermophysical properties. Studies on glass transition dynamics were conducted on systems with a range of structural features including an As4S3 inorganic molecular glass former, an As-P-S system where molecules are bonded to the As-S network, and network glasses in the Ge-Se system. Timescales of the rotational dynamics of As4S3 cage molecules in the molecular As-sulfide glass and supercooled liquid show remarkably large decoupling from the timescales of viscous flow and shear relaxation at temperatures below and near Tg (312K). Next, the dynamic behavior of a (As 2S3)90(P2S5)10 glass, which is proposed to consist of As2P2S8 molecular structures which are connected to an As-S network, is investigated with 31P NMR. The rotational dynamics of selenium chains in network forming GexSe100-x glasses and supercooled liquids with 5≤x≤23 are investigated with variable temperature 77Se NMR spectroscopy to determine the relationship between rigidity percolation and dynamic behavior. The timescale of the motion of the Se atoms is observed to be nearly identical for x≤17 and
s-Process in low metallicity Pb stars.
NASA Astrophysics Data System (ADS)
Bisterzo, S.; Gallino, R.; Straniero, O.; Ivans, I. I.; Käppeler, F.; Aoki, W.
We consider a sample of very metal-poor, C-rich, s-rich and lead-rich stars observed at high-resolution spectroscopy, and some recent spectroscopic data of C+s-rich stars obtained at moderate resolution. The spectroscopic data of these stars are interpreted with AGB theoretical models of different 13C-pocket efficiencies, initial mass and initial r-enrichment. When lead is not measured we give our theoretical prediction. The observed stars are not on the AGB phase, but are main sequence or giant stars. They acquired the C and s enrichments by mass transfer in a close binary system from the more massive companion while on the AGB (now a white dwarf). A considerable fraction of the stars show both high s and r enrichments. To explain the s+r enriched stars we assume a parental cloud already enriched in r-elements. The measurement of Nb is an indicator of an extrinsic AGB in a binary system. The intrinsic indicator [hs/ls] constrains the initial mass, while [Pb/hs] and [Pb/ls] are a measure of the s-process efficiency. The apparent discrepancies of C and N abundances may be reconciled by assuming a strong cool bottom process occurring during the AGB. An important primary production of light elements, from Ne to Si, increasing with the star mass, is predicted for AGB models at very low metallicity, induced by n capture on primary 22Ne and its progenies.
NASA Astrophysics Data System (ADS)
Shepard, Michael K.; Taylor, Patrick A.; Nolan, Michael C.; Howell, Ellen S.; Springmann, Alessondra; Giorgini, Jon D.; Warner, Brian D.; Harris, Alan W.; Stephens, Robert; Merline, William J.; Rivkin, Andrew; Benner, Lance A. M.; Coley, Dan; Clark, Beth Ellen; Ockert-Bell, Maureen; Magri, Christopher
2015-01-01
Using the S-band radar at Arecibo Observatory, we observed thirteen X/M-class asteroids; nine were previously undetected and four were re-observed, bringing the total number of Tholen X/M-class asteroids observed with radar to 29. Of these 29M-class asteroids, 13 are also W-class, defined as M-class objects that also display a 3-μm absorption feature which is often interpreted as the signature of hydrated minerals (Jones, T.D., Lebofsky, L.A., Lewis, J.S., Marley, M.S. [1990]. Icarus 88, 172-192; Rivkin, A.S., Howell, E.S., Britt, D.T., Lebofsky, L.A., Nolan, M.C., Branston, D.D. [1995]. Icarus 117, 90-100; Rivkin, A.S., Howell, E.S., Lebofsky, L.A., Clark, B.E., Britt, D.T. [2000]. Icarus 145, 351-368). Consistent with our previous work (Shepard, M.K. et al. [2008]. Icarus 195, 184-205; Shepard, M.K., Harris, A.W., Taylor, P.A., Clark, B.E., Ockert-Bell, M., Nolan, M.C., Howell, E.S., Magri, C., Giorgini, J.D., Benner, L.A.M. [2011]. Icarus 215, 547-551), we find that 38% of our sample (11 of 29) have radar albedos consistent with metal-dominated compositions. With the exception of 83 Beatrix and 572 Rebekka, the remaining objects have radar albedos significantly higher than the mean S- or C-class asteroid (Magri, C., Nolan, M.C., Ostro, S.J., Giorgini, J.D. [2007]. Icarus 186, 126-151). Seven of the eleven high-radar-albedo asteroids, or 64%, also display a 3-μm absorption feature (W-class) which is thought to be inconsistent with the formation of a metal dominated asteroid. We suggest that the hydration absorption could be a secondary feature caused by low-velocity collisions with hydrated asteroids, such as CI or CM analogs, and subsequent implantation of the hydrated minerals into the upper regolith. There is recent evidence for this process on Vesta (Reddy, V. et al. [2012]. Icarus 221, 544-559; McCord, T.B. et al. [2012]. Nature 491, 83-86; Prettyman, T.H. et al. [2012]. Science 338, 242-246; Denevi, B.W. et al. [2012]. Science 338, 246-249). Eleven members of our sample show bifurcated radar echoes at some rotation phases; eight of these are high radar albedo targets. One interpretation of a bifurcated echo is a contact binary, like 216 Kleopatra, and several of our sample are contact binary candidates. However, evidence for other targets indicates they are not contact binaries. Instead, we hypothesize that these asteroids may have large-scale variations in surface bulk density, i.e. isolated patches of metal-rich and silicate-rich regions at the near-surface, possibly the result of collisions between metal and silicate-rich asteroids.
Liu, W.; Montana, Vedrana; Parpura, Vladimir; Mohideen, U.
2010-01-01
We use an Atomic Force Microscope based single molecule measurements to evaluate the activation free energy in the interaction of SNARE proteins syntaxin 1A, SNAP25B and synaptobrevin 2 which regulate intracellular fusion of vesicles with target membranes. The dissociation rate of the binary syntaxin-synaptobrevin and the ternary syntaxin-SNAP25B-synaptobrevin complex was measured from the rupture force distribution as a function of the rate of applied force. The temperature dependence of the spontaneous dissociation rate was used to obtain the activation energy to the transition state of 19.8 ± 3.5 kcal/mol = 33 ± 6 kBT and 25.7 ± 3.0 kcal/mol = 43 ± 5 kBT for the binary and ternary complex, respectively. They are consistent with those measured previously for the ternary complex in lipid membranes and are of order expected for bilayer fusion and pore formation. The ΔG was 12.4–16.6 kcal/mol = 21–28 kBT and 13.8–18.0 kcal/mol = 23–30 kBT for the binary and ternary complex, respectively. The ternary complex was more stable by 1.4 kcal/mol = 2.3 kBT, consistent with the spontaneous dissociation rates. The higher adhesion energies and smaller molecular extensions measured with SNAP25B point to its possible unique and important physiological role in tethering/docking the vesicle in closer proximity to the plasma membrane and increasing the probability for fusion completion. PMID:20107522
2011-04-04
10989). 13. SUPPLEMENTARY NOTES For publication in the AIAA Journal of Fluorine Chemistry. 14. ABSTRACT Eight binary salts that pair triazolium...4]. This characteristic permitted the synthesis of the B12F122– dianion by electrophilic attack of supercritical HF in 1992 (it was isolated as Cs2...B. A. Wight, H. L. Ammon, D. V. Peryshkov, S. H. Strauss, Org. Lett. 12 (2010) 2714–2717. [9] D. V. Peryshkov, S. H. Strauss J. Fluorine Chem. 131
Population trends of binary near-Earth asteroids based on radar and lightcurves observations
NASA Astrophysics Data System (ADS)
Brozovic, Marina; Benner, Lance A. M.; Naidu, Shantanu P.; Taylor, Patrick A.; Busch, Michael W.; Margot, Jean-Luc; Nolan, Michael C.; Howell, Ellen S.; Springmann, Alessondra; Giorgini, Jon D.; Shepard, Michael K.; Magri, Christopher; Richardson, James E.; Rivera-Valentin, Edgard G.; Rodriguez-Ford, Linda A.; Zambrano Marin, Luisa Fernanda
2016-10-01
The Arecibo and Goldstone planetary radars are invaluable instruments for the discovery and characterization of binary and triple asteroids in the near-Earth asteroid (NEA) population. To date, 41 out of 56 known binaries and triples (~73% of the objects) have been discovered by radar and 49 of these multiple systems have been detected by radar. Their absolute magnitudes range from 12.4 for (1866) Sisyphus to 22.6 for 2015 TD144 and have a mean and rms dispersion of 18.1+-2.0. There is a pronounced decrease in the abundance of binaries for absolute magnitudes H>20. One of the smallest binaries, 1994 CJ1, with an absolute magnitude H=21.4, is also the most accessible binary for a spacecraft rendezvous. Among 365 NEAs with H<22 (corresponding to diameters larger than ~ 140 m) detected by radar since 1999, ~13% have at least one companion. Two triple systems are known, (15391) 2001 SN263 and (136617) 1994 CC, but this is probably an underestimate due to low signal to noise ratios (SNRs) for many of the binary radar detections. Taxonomic classes have been reported for 41 out of 56 currently known multiple systems and some trends are starting to emerge: at least 50% of multiple asteroid systems are S, Sq, Q, or Sk, and at least 20% are optically dark (C, B, P, or U). Thirteen V-class NEAs have been observed by radar and six of them are binaries. Curiously, a comparable number of E-class objects have been detected by radar, but none is known to be a binary.
Ceglia, I; Acconcia, S; Fracasso, C; Colovic, M; Caccia, S; Invernizzi, R W
2004-01-01
Microdialysis was used to study the acute and chronic effects of escitalopram (S-citalopram; ESCIT) and chronic citalopram (CIT), together with the 5-HT1A receptor antagonist WAY100,635 (N-[2-[methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexane carboxamide trihydrochloride) and the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), on extracellular 5-hydroxytryptamine (5-HT) levels in the rat prefrontal cortex. Extracellular 5-HT rose to 234 and 298% of basal values after subcutaneous (s.c.) acute doses of 0.15 and 0.63 mg kg−1 ESCIT. No further increase was observed at 2.5 mg kg−1 ESCIT (290%). The effect of 13-day s.c. infusion of 10 mg kg−1day−1 ESCIT on extracellular 5-HT (422% of baseline) was greater than after 2 days (257% of baseline), whereas exposure to ESCIT was similar. In contrast, the increase in extracellular 5-HT induced by the infusion of CIT for 2 (306%) and 13 days (302%) was similar. However, brain and plasma levels of S-citalopram in rats infused with CIT for 13 days were lower than after 2 days. Acute treatment with 2.5 mg kg−1 ESCIT or 5 mg kg−1 CIT raised extracellular 5-HT by 243 and 276%, respectively, in rats given chronic vehicle but had no effect in rats given ESCIT (10 mg kg−1 day−1) or CIT (20 mg kg−1 day−1) for 2 or 13 days, suggesting that the infused doses had maximally increased extracellular 5-HT. WAY100,635 (0.1 mg kg−1 s.c.) increased extracellular 5-HT levels by 168, 174 and 169% of prechallenge values in rats infused with vehicle or ESCIT for 2 or 13 days, respectively. WAY100,635 enhanced extracellular 5-HT levels to 226, 153 and 164% of prechallenge values in rats infused with vehicle or CIT for 2 and 13 days, respectively. 8-OH-DPAT (0.025 mg kg−1) reduced extracellular 5-HT by 54% in control rats, but had no effect in those given ESCIT and CIT for 13 days. This series of experiments led to the conclusion that chronic treatment with ESCIT desensitizes the 5-HT1A receptors, regulating the release of 5-HT in the prefrontal cortex and enhances the effect of the drug on extracellular 5-HT. They also indicate that chronic treatment with ESCIT and CIT did not prevent WAY100,635 from raising extracellular 5-HT. PMID:15148253
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morales, Sebastien B.; Bennett, Christopher J.; Le Picard, Sebastien D.
2011-11-20
We present a joint crossed molecular beam and kinetics investigation combined with electronic structure and statistical calculations on the reaction of the ground-state cyano radical, CN(X {sup 2}{Sigma}{sup +}), with the 1,3-butadiene molecule, H{sub 2}CCHCHCH{sub 2}(X {sup 1} A{sub g}), and its partially deuterated counterparts, H{sub 2}CCDCDCH{sub 2}(X {sup 1} A{sub g}) and D{sub 2}CCHCHCD{sub 2}(X {sup 1} A{sub g}). The crossed beam studies indicate that the reaction proceeds via a long-lived C{sub 5}H{sub 6}N complex, yielding C{sub 5}H{sub 5}N isomer(s) plus atomic hydrogen under single collision conditions as the nascent product(s). Experiments with the partially deuterated 1,3-butadienes indicate thatmore » the atomic hydrogen loss originates from one of the terminal carbon atoms of 1,3-butadiene. A combination of the experimental data with electronic structure calculations suggests that the thermodynamically less favorable 1-cyano-1,3-butadiene isomer represents the dominant reaction product; possible minor contributions of less than a few percent from the aromatic pyridine molecule might be feasible. Low-temperature kinetics studies demonstrate that the overall reaction is very fast from room temperature down to 23 K with rate coefficients close to the gas kinetic limit. This finding, combined with theoretical calculations, indicates that the reaction proceeds on an entrance barrier-less potential energy surface (PES). This combined experimental and theoretical approach represents an important step toward a systematic understanding of the formation of complex, nitrogen-bearing molecules-here on the C{sub 5}H{sub 6}N PES-in low-temperature extraterrestrial environments. These results are compared to the reaction dynamics of D1-ethynyl radicals (C{sub 2}D; X {sup 2}{Sigma}{sup +}) with 1,3-butadiene accessing the isoelectronic C{sub 6}H{sub 7} surface as tackled earlier in our laboratories.« less
Hu, S W; Yang, L W; Tian, Y; Wei, X L; Ding, J W; Zhong, J X; Chu, Paul K
2014-10-01
A proof of concept integrating binary p-n heterojunctions into a semiconductor hybrid photocatalyst is demonstrated by non-covalent doping of graphite-like carbon nitride (g-C3N4) with ultrathin GO and MoS2 nanosheets using a facile sonochemical method. In this unique ternary hybrid, the layered MoS2 and GO nanosheets with a large surface area enhance light absorption to generate more photoelectrons. On account of the coupling between MoS2 and GO with g-C3N4, the ternary hybrid possesses binary p-n heterojunctions at the g-C3N4/MoS2 and g-C3N4/GO interfaces. The space charge layers created by the p-n heterojunctions not only enhance photogeneration, but also promote charge separation and transfer of electron-hole pairs. In addition, the ultrathin MoS2 and GO with high mobility act as electron mediators to facilitate separation of photogenerated electron-hole pairs at each p-n heterojunction. As a result, the ternary hybrid photocatalyst exhibits improved photoelectrochemical and photocatalytic activity under visible light irradiation compared to other reference materials. The results provide new insights into the large-scale production of semiconductor photocatalysts. Copyright © 2014 Elsevier Inc. All rights reserved.
A Model of Airflow and Diffusion in Complex Terrain (MADICT).
1985-11-01
104 , 784-792. Ludwig, F.L. 1982: "Effect of a Change in Atmospheric Stability on the Growth Rate of Puffs Used in Plume Simulation Models," J. Appl...INPUTS C IF (NOPUF.EQ.0)THEN DO 2305 K=1, NFUNCT DOTX (1, K) =DOTX (0, K) 2305 CONTINUE IHOUR=N I-IHOUR+1)NOPUF=NOPUFF +1 ""- END IF RETURN END 104 ...CM) C DO 100 IX-0,INDX DO 100 IY0.,INDY RHB (IXIyl)I = (XRuAS (IXIY’l MTIN /10.0 RHS1 (IX, IY 2)= (XCR1S (IX, IY, 2) -Z4IN /100. 0 IF(RHS (IXI,2
Akutagawa, Tomoyuki; Motokizawa, Takeshi; Matsuura, Kazumasa; Nishihara, Sadafumi; Noro, Shin-ichiro; Nakamura, Takayoshi
2006-03-30
Sandwich-type supramolecular cation structures of (M(+))([12]crown-4)(2) complexes (M(+) = Li(+), Na(+), K(+), and Rb(+)) were introduced as countercations to the [Ni(dmit)(2)](-) anion, which bears an S = (1)/(2) spin, to form novel magnetic crystals (dmit(2-) = 2-thione-1,3-dithiole-4,5-dithiolate). The zigzag arrangement of Li(+)([12]crown-4)(2) cations in Li(+)([12]crown-4)(2)[Ni(dmit)(2)](-) salt induced weak intermolecular interactions of [Ni(dmit)(2)](-) dimers, whose magnetic spins were isolated from each other. The molecular arrangements of cations and anions in M(+)([12]crown-4)(2)[Ni(dmit)(2)](-) salts (M(+) = Na(+), K(+), and Rb(+)) were isostructural to each other. In the case of Na(+)([12]crown-4)(2)[Ni(dmit)(2)](-), the space group C2/m changed to C2/c with a lowering in temperature from 298 to 100 K. This structural change occurred at 222.5 K as a first-order phase transition. The space group C2/m (T = 298 K) in the salt K(+)([12]crown-4)(2)[Ni(dmit)(2)](-) also changed to C2/c (T = 100 K), which transition occurred at 270 K. Crystal structural analyses at 298 and 100 K revealed changes in both supramolecular cation conformation and [Ni(dmit)(2)](-) anion arrangements. The transition from C2/m to C2/c crystals generated a dipole moment in the Na(+)([12]crown-4)(2) and K(+)([12]crown-4)(2) structures, which were reconstructed to cancel the net dipole moment of the C2/c crystals. These cation transformations led to changes in intermolecular interactions between the [Ni(dmit)(2)](-) anions via structural rearrangements. The crystal structure of C2/c was stabilized in Rb(+)([12]crown-4)(2)[Ni(dmit)(2)](-) at 298 K. The [Ni(dmit)(2)](-) configuration in these salts with the C2/c space group was a one-dimensional uniform chain, which showed the temperature-dependent magnetic susceptibility of a one-dimensional linear Heisenberg antiferromagnetic chain.
Studies of Lubricating Materials in Vacuum
NASA Technical Reports Server (NTRS)
Buckley, D. H.; Johnson, R. L.; Swikert, M. A.
1964-01-01
Lubricating materials for use in a vacuum environment have been the subject of a series of experimental investigations. Evaporation properties were evaluated for solid polymeric compositions. Friction and wear studies explored the behavior during sliding contact for series of polymeric compositions, binary alloys containing soft film-forming phases, complex alloys with film-forming materials, and a burnished MoS2 film. Friction and wear experiments were conducted at 10(exp-9)mm Hg with a 3/16-inch-radius-hemisphere rider specimen sliding on the flat surface of a rotating 2-1/2-inch-diameter disk specimen with materials that had low rates of evaporation. The influence of fillers in polytetrafluoroethylene (PTFE) on decomposition during vacuum friction studies was determined with a mass spectrometer. A real advantage in reducing decomposition and improving friction wear properties is gained by adding fillers (e.g., copper) that improve thermal conductivity through the composite materials. A polyimide and an epoxy-MoS2 composition material were found to have better friction and wear properties than PTFE compositions. A series of alloys (cast binary as well as more complex alloys) that contained microinclusions of potential film-forming material was studied. These materials replaced the normal surface oxides as they were worn away on sliding contact. Iron sulfide, nickel oxide, and tin are typical film-forming materials employed and were demonstrated to be effective in inhibiting surface welding and reducing friction. A burnished MoS2 film applied to type 440-C stainless steel in argon with a rotating soft wire brush had good endurance properties but somewhat higher friction than commercially available bonded films. An oil film applied to the burnished MoS2 markedly reduced its endurance life.
Wategaonkar, Sanjay; Bhattacherjee, Aditi
2018-05-03
The N-H···S hydrogen bond, even though classified as an unconventional hydrogen bond, is found to bear important structural implications on protein structure and folding. In this article, we report a gas-phase study of the N-H···S hydrogen bond between the model compounds of histidine (benzimidazole, denoted BIM) and methionine (dimethyl sulfide, diethyl sulfide, and tetrahydrothiophene, denoted Me 2 S, Et 2 S, and THT, respectively). A combination of laser spectroscopic methods such as laser-induced fluorescence (LIF), two-color resonant two-photon ionization (2cR2PI), and fluorescence depletion by infrared spectroscopy (FDIR) is used in conjunction with DFT and ab initio calculations to characterize the nature of this prevalent H-bonding interaction in simple bimolecular complexes. A single conformer was found to exist for the BIM-Me 2 S complex, whereas the BIM-Et 2 S and BIM-THT complexes showed the presence of three and two conformers, respectively. These conformers were characterized on the basis of IR spectroscopic results and electronic structure calculations. Quantum theory of atoms in molecules (QTAIM), natural bond orbital (NBO), and energy decomposition (NEDA) analyses were performed to investigate the nature of the N-H···S H-bond. Comparison of the results with the N-H···O type of interactions in BIM and indole revealed that the strength of the N-H···S H-bond is similar to N-H···O in these binary gas-phase complexes.
Alkorta, Ibon; Legon, Anthony C
2017-10-23
It is shown that the dissociation energy D e for the process B⋯A = B + A for 250 complexes B⋯A composed of 11 Lewis bases B (N₂, CO, HC≡CH, CH₂=CH₂, C₃H₆, PH₃, H₂S, HCN, H₂O, H₂CO and NH₃) and 23 Lewis acids (HF, HCl, HBr, HC≡CH, HCN, H₂O, F₂, Cl₂, Br₂, ClF, BrCl, H₃SiF, H₃GeF, F₂CO, CO₂, N₂O, NO₂F, PH₂F, AsH₂F, SO₂, SeO₂, SF₂, and SeF₂) can be represented to good approximation by means of the equation D e = c ' N B E A , in which N B is a numerical nucleophilicity assigned to B, E A is a numerical electrophilicity assigned to A, and c ' is a constant, conveniently chosen to have the value 1.00 kJ mol -1 here. The 250 complexes were chosen to cover a wide range of non-covalent interaction types, namely: (1) the hydrogen bond; (2) the halogen bond; (3) the tetrel bond; (4) the pnictogen bond; and (5) the chalcogen bond. Since there is no evidence that one group of non-covalent interaction was fitted any better than the others, it appears the equation is equally valid for all the interactions considered and that the values of N B and E A so determined define properties of the individual molecules. The values of N B and E A can be used to predict the dissociation energies of a wide range of binary complexes B⋯A with reasonable accuracy.
Wharton, Christopher W.; Cornish-Bowden, Athel; Brocklehurst, Keith; Crook, Eric M.
1974-01-01
1. N-Benzoyl-l-serine methyl ester was synthesized and evaluated as a substrate for bromelain (EC 3.4.22.4) and for papain (EC 3.4.22.2). 2. For the bromelain-catalysed hydrolysis at pH7.0, plots of [S0]/vi (initial substrate concn./initial velocity) versus [S0] are markedly curved, concave downwards. 3. Analysis by lattice nomography of a modifier kinetic mechanism in which the modifier is substrate reveals that concave-down [S0]/vi versus [S0] plots can arise when the ratio of the rate constants that characterize the breakdown of the binary (ES) and ternary (SES) complexes is either less than or greater than 1. In the latter case, there are severe restrictions on the values that may be taken by the ratio of the dissociation constants of the productive and non-productive binary complexes. 4. Concave-down [S0]/vi versus [S0] plots cannot arise from compulsory substrate activation. 5. Computational methods, based on function minimization, for determination of the apparent parameters that characterize a non-compulsory substrate-activated catalysis are described. 6. In an attempt to interpret the catalysis by bromelain of the hydrolysis of N-benzoyl-l-serine methyl ester in terms of substrate activation, the general substrate-activation model was simplified to one in which only one binary ES complex (that which gives rise directly to products) can form. 7. In terms of this model, the bromelain-catalysed hydrolysis of N-benzoyl-l-serine methyl ester at pH7.0, I=0.1 and 25°C is characterized by Km1 (the dissociation constant of ES)=1.22±0.73mm, k (the rate constant for the breakdown of ES to E+products, P)=1.57×10−2±0.32×10−2s−1, Ka2 (the dissociation constant that characterizes the breakdown of SES to ES and S)=0.38±0.06m, and k′ (the rate constant for the breakdown of SES to E+P+S)=0.45±0.04s−1. 8. These parameters are compared with those in the literature that characterize the bromelain-catalysed hydrolysis of α-N-benzoyl-l-arginine ethyl ester and of α-N-benzoyl-l-arginine amide; Km1 and k for the serine ester hydrolysis are somewhat similar to Km and kcat. for the arginine amide hydrolysis and Kas and k′ for the serine ester hydrolysis are somewhat similar to Km and kcat. for the arginine ester hydrolysis. 9. A previous interpretation of the inter-relationships of the values of kcat. and Km for the bromelain-catalysed hydrolysis of the arginine ester and amide substrates is discussed critically and an alternative interpretation involving substantial non-productive binding of the arginine amide substrate to bromelain is suggested. 10. The parameters for the bromelain-catalysed hydrolysis of the serine ester substrate are tentatively interpreted in terms of non-productive binding in the binary complex and a decrease of this type of binding by ternary complex-formation. 11. The Michaelis parameters for the papain-catalysed hydrolysis of the serine ester substrate (Km=52±4mm, kcat.=2.80±0.1s−1 at pH7.0, I=0.1, 25.0°C) are similar to those for the papain-catalysed hydrolysis of methyl hippurate. 12. Urea and guanidine hydrochloride at concentrations of 1m have only small effects on the kinetic parameters for the hydrolysis of the serine ester substrate catalysed by bromelain and by papain. PMID:4455211
Zhang, Hang; Gao, Qiuming; Qian, Weiwei; Xiao, Hong; Li, Zeyu; Ma, Li; Tian, Xuehui
2018-06-06
A N,O-codoped hierarchical porous nanocomposite consisting of binary reduced graphene oxide and pyrolytic carbon (rGO/PC) from chitosan is fabricated. The optimized rGO/PC possesses micropores with size distribution concentrated around 1.1 nm and plenty of meso/macropores. The Brunauer-Emmett-Teller specific surface area is 480.8 m 2 g -1 , and it possesses impressively large pore volume of 2.14 cm 3 g -1 . On the basis of the synergistic effects of the following main factors: (i) the confined space effect in the hierarchical porous binary carbonaceous matrix; (ii) the anchor effects by strong chemical bonds with codoped N and O atoms; and (iii) the good flexibility and conductivity of rGO, the rGO/PC/S holding 75 wt % S exhibits high performance as Li-S battery cathode. Specific capacity of 1625 mA h g -1 can be delivered at 0.1 C (1 C = 1675 mA g -1 ), whereas 848 mA h g -1 can be maintained after 300 cycles at 1 C. Even at high rate of 5 C, 412 mA h g -1 can be restrained after 1000 cycles.
The binary Kuiper-belt object 1998 WW31.
Veillet, Christian; Parker, Joel Wm; Griffin, Ian; Marsden, Brian; Doressoundiram, Alain; Buie, Marc; Tholen, David J; Connelley, Michael; Holman, Matthew J
2002-04-18
The recent discovery of a binary asteroid during a spacecraft fly-by generated keen interest, because the orbital parameters of binaries can provide measures of the masses, and mutual eclipses could allow us to determine individual sizes and bulk densities. Several binary near-Earth, main-belt and Trojan asteroids have subsequently been discovered. The Kuiper belt-the region of space extending from Neptune (at 30 astronomical units) to well over 100 AU and believed to be the source of new short-period comets-has become a fascinating new window onto the formation of our Solar System since the first member object, not counting Pluto, was discovered in 1992 (ref. 13). Here we report that the Kuiper-belt object 1998 WW31 is binary with a highly eccentric orbit (eccentricity e approximately 0.8) and a long period (about 570 days), very different from the Pluto/Charon system, which was hitherto the only previously known binary in the Kuiper belt. Assuming a density in the range of 1 to 2 g cm-3, the albedo of the binary components is between 0.05 and 0.08, close to the value of 0.04 generally assumed for Kuiper-belt objects.
Redox interplay of oxo-thio-tungsten centers with sulfur-donor co-ligands.
Thomas, Simon; Eagle, Aston A; Sproules, Stephen A; Hill, Jason P; White, Jonathan M; Tiekink, Edward R T; George, Graham N; Young, Charles G
2003-09-22
The oxo-thio-W(VI) complexes TpWOS(S(2)PR(2)-S) and TpWOS(pyS-S) (Tp = hydrotris(3,5-dimethylpyrazol-1-yl)borate, R = OEt, Ph; pyS = pyridine-2-thiolate) have been prepared and characterized by microanalytical, spectroscopic, and structural techniques. Crystals of the 1,2-dichloroethane hemisolvate of TpWOS(S(2)PPh(2)-S) belong to the triclinic space group Ponemacr; with a = 10.732(6) A, b = 16.91(1) A, c = 10.021(4) A, alpha = 104.40(4) degrees, beta = 107.52(3) degrees, gamma = 96.09(5) degrees, V = 1647(1) A(3) for Z = 2. The complex exhibits a distorted octahedral structure featuring a facial tridentate Tp ligand and mutually cis terminal oxo (W-O(1) = 1.712(7) A), terminal thio (W-S(1) = 2.162(3) A), and monodentate dithiophosphinate ligands. X-ray absorption and extended X-ray absorption fine structure results support a related oxo-thio formulation for TpWOS(pyS-S). The complexes are reduced to the corresponding oxo-thio-W(V) anions, [TpWOS(S(2)PR(2)-S)](-) and [TpWOS(pyS-S)](-), which exhibit highly anisotropic EPR spectra. They are oxidized to form the EPR-active (dithio)oxo-W(V) cations, [TpWO(S(3)PR(2)-S,S')](+) and [TpWO(pyS(2)-N,S)](+) (pyS(2) = pyridine-2-dithio). Green [TpWO(pyS(2)-N,S)]BF(4), formed in the reaction of TpWOS(pyS) and NOBF(4), has been isolated and spectroscopically and structurally characterized. Crystals of [TpWO(pyS(2)-N,S)]BF(4) belong to the monoclinic space group Cc with a = 16.007(5) A, b = 14.091(4) A, c = 13.608(4) A, beta = 124.525(4) degrees, V = 2528.8(13) A(3) for Z = 4. The cation exhibits a distorted octahedral structure featuring facial tridentate Tp, terminal oxo (W-O(1) = 1.632(12) A), and bidentate pyridine-2-dithio-N,S (W-S(1) = 2.317(7) A, S(1)-S(2) = 2.037(9) A) ligands. The structures and redox behavior of the complexes are compared and contrasted with those of the related molybdenum complexes, TpMo(VI)OS(S(2)PR(2)-S) and TpMo(IV)O(pyS(2)-N,S) (Hill, J. P.; Laughlin, L. J.; Gable, R. W.; Young, C. G. Inorg. Chem. 1996, 35, 3447).
Kachhap, Sangita; Priyadarshini, Pragya; Singh, Balvinder
2017-05-01
Aristaless (Al) and clawless (Cll) homeodomains that are involved in leg development in Drosophila melanogaster are known to bind cooperatively to 5'-(T/C)TAATTAA(T/A)(T/A)G-3' DNA sequence, but the mechanism of their binding to DNA is unknown. Molecular dynamics (MD) studies have been carried out on binary, ternary, and reconstructed protein-DNA complexes involving Al, Cll, and DNA along with binding free energy analysis of these complexes. Analysis of MD trajectories of Cll-3A01, binary complex reveals that C-terminal end of helixIII of Cll, unwind in the absence of Al and remains so in reconstructed ternary complex, Cll-3A01-Al. In addition, this change in secondary structure of Cll does not allow it to form protein-protein interactions with Al in the ternary reconstructed complex. However, secondary structure of Cll and its interactions are maintained in other reconstructed ternary complex, Al-3A01-Cll where Cll binds to Al-3A01, binary complex to form ternary complex. These interactions as observed during MD simulations compare well with those observed in ternary crystal structure. Thus, this study highlights the role of helixIII of Cll and protein-protein interactions while proposing likely mechanism of recognition in ternary complex, Al-Cll-DNA.
The Inhomogeneous Light Shift in Alkali Atoms.
1985-06-24
N AMP’. LAS R 1GEEAOCON R ’", DONTROLLERR MA LNETSHEL Fig. 1. Exp mn ta Ar a g m n . S i c o i i n A and B corr spon to the arSran e tsO used/ PtoS...Calculation Parameters laser linewidth A~V La 100 MHz laser beam diameter a - 0.45 cm absorption linewidth DV 50 ~ longitudinal relaxation rate y 100...Verlag, Berlin-Heidelberg-New York, 1975), pp. 176- 185. 12. S. Pancharatnam, J. Opt. Soc. Am. 56, 1636 (1966). 13. C. Cohen-Tannoudji, Metrologia 13
Arsac, Laurent M
2002-05-01
The present study was designed to investigate the role of reduced air density on the energetics of 100 m running at altitude. A mathematical supply-demand model was used where supply had two components, aerobic and anaerobic and demand had three components: the cost of overcoming non-aerodynamic forces (C(na)), the cost of overcoming air resistance (C(aero)), and the cost due to changes in the runner's kinetic energy (C(kin)). Actual instantaneous-speed curves recorded in 100 m world champions were modelled at sea level. Then I calculated improvements in 100 m running times and changes in the components of the energy cost with changes in altitude from 0 m to 4,000 m. For the 100 m world championship for men, the model predicted times of 9.88 s at sea level, 9.80 s at 1,000 m, 9.73 s at 2,000 m, 9.64 s at 4,000 m and 9.15 s in the hypothetical situation where the air resistance was nil. In the counterpart for women the corresponding times were 10.85 s, 10.76 s, 10.70 s, 10.60 s and 10.04 s. The C(aero) was 12%-13% of demand at sea level, 10%-11% at 2,000 m and 8%-9% at 4,000 m. When C(aero) decreased this led to better performance by making more energy available for acceleration. Accordingly, C(kin) increased from 20%-24% at sea level to 23%-27% at 4,000 m. There was no effect of altitude specific to body size.
NASA Astrophysics Data System (ADS)
Alaghaz, Abdel-Nasser M. A.; Zayed, Mohamed E.; Alharbi, Suliman A.
2015-03-01
The Schiff's base derived from condensation of s-triazole (4-amino-5-mercapto-3-methyl-S-triazole) with pyridine-2-aldehyde and their corresponding Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized. The isolated solid complexes were characterized by elemental analyses, molar conductance, spectral (IR, UV-Vis, 1H NMR, mass), magnetic moment and thermal measurements. The IR spectral data suggest that the ligand coordinate in a tridentate manner (SNN) via the one thiol (SH), one pyridine ring and the azomethine (Cdbnd N) groups. The data show that the complexes have composition of ML2 type. The activation of thermodynamic parameters are calculated using Coats-Redfern, Horowitz-Metzger (HM), and Piloyan-Novikova (PN). The octahedral geometry of the complexes is confirmed using DFT method from DMOL3 calculations and ligand field parameters. Protonation constants of Schiff base and stability constants of their binary metal complexes have been determined potentiometrically in 50% DMSO-water media at 25 °C and ionic strength 0.10 M potassium nitrate. The biological activity of these compounds against various fungi has been investigated.
Lead(II) Complex Formation with L-cysteine in Aqueous Solution
Jalilehvand, Farideh; Sisombath, Natalie S.; Schell, Adam C.; Facey, Glenn A.
2015-01-01
The lead(II) complexes formed with the multidentate chelator L-cysteine (H2Cys) in alkaline aqueous solution were studied using 207Pb, 13C and 1H NMR, Pb LIII-edge X-ray absorption and UV-vis. spectroscopic techniques, complemented by electro-spray ion mass spectrometry (ESI-MS). The H2Cys/Pb(II) mole ratios were varied from 2.1 to 10.0 for two sets of solutions with CPb(II) = 0.01 and 0.1 M, respectively, prepared at pH values (9.1 – 10.4) for which precipitates of Pb(II)-cysteine dissolved. At low H2Cys/Pb(II) mole ratios (2.1 – 3.0) a mixture of the dithiolate [Pb(S,N-Cys)2]2− and [Pb(S,N,O-Cys)(S-HCys)]− complexes with the average Pb-(N/O) and Pb-S distances 2.42 ± 0.04 Å and 2.64 ± 0.04 Å, respectively, was found to dominate. At high concentration of free cysteinate (> 0.7 M) a significant amount converts to the trithiolate [Pb(S,N-Cys)(S-HCys)2]2−, including a minor amount of a PbS3 coordinated [Pb(S-HCys)3]− complex. The coordination mode was evaluated by fitting linear combinations of EXAFS oscillations to the experimental spectra, and by the 207Pb NMR signals in the chemical shift range δPb = 2006 – 2507 ppm, which became increasingly deshielded with increasing free cysteinate concentration. One-pulse magic angle spinning (MAS) 207Pb NMR spectra of crystalline Pb(aet)2 (Haet = 2-aminoethanethiol or cysteamine) with PbS2N2 coordination were measured for comparison (δiso = 2105 ppm). The UV-vis. spectra displayed absorption maxima at 298 – 300 nm (S− → PbII charge transfer) for the dithiolate PbS2N(N/O) species; with increasing ligand excess a shoulder appeared at ∼ 330 nm for the trithiolate PbS3N and PbS3 (minor) complexes. The results provide spectroscopic fingerprints for structural models for Pb(II) coordination modes to proteins and enzymes. PMID:25695880
Rapid fluctuations in the northern Baltic Sea H2S layer
NASA Astrophysics Data System (ADS)
Kankaanpää, Harri T.; Virtasalo, Joonas J.
2017-12-01
Hydrogen sulfide (H2S) is linked to water quality deterioration in the Baltic Sea, with widespread seafloor hypoxia. We examined the vertical and temporal variability of in situ [H2S], oxygen concentration ([O2]), temperature (T) and pH at weekly, hourly and minute intervals at 13 locations in the western Gulf of Finland in 2013-2014. The main target was the 60-100 m water depth range, containing 3.2-290 μM O2 and 6.3-22.6 μM H2S. Where gas was detected by acoustic surveys, the structure of the H2S layer was more complex compared to stations devoid of gas. Local minima and maxima in pH frequently occurred near the H2S upper boundary (redox transition zone). Except for the homogeneous, tranquil zone above the seafloor at some stations, substantial rapid changes in hydrographic conditions were common. Typically, a layer of marked temporal T variability was present atop or within the topmost H2S layers. The largest temporal changes over a weekly period were - 0.44 °C/- 10.8 μM H2S/- 0.12 pH units (at seafloor level), + 0.18 °C/+7.9 μM H2S between casts (1 h) and + 0.03 °C/- 2.5 μM H2S per minute (high resolution logging). Abrupt [H2S] changes were recorded at two stations with sediments containing free gas. The T and [H2S] changes were synchronous at several layers, reflecting water movement. We conclude that rapid changes occur in hydrographic conditions in the near-bottom H2S layer in the northern Baltic Sea, especially at locations where free gas is present in the underlying sediments.
NASA Astrophysics Data System (ADS)
Murphy, Simon J.; Moe, Maxwell; Kurtz, Donald W.; Bedding, Timothy R.; Shibahashi, Hiromoto; Boffin, Henri M. J.
2018-03-01
The orbital parameters of binaries at intermediate periods (102-103 d) are difficult to measure with conventional methods and are very incomplete. We have undertaken a new survey, applying our pulsation timing method to Kepler light curves of 2224 main-sequence A/F stars and found 341 non-eclipsing binaries. We calculate the orbital parameters for 317 PB1 systems (single-pulsator binaries) and 24 PB2s (double-pulsators), tripling the number of intermediate-mass binaries with full orbital solutions. The method reaches down to small mass ratios q ≈ 0.02 and yields a highly homogeneous sample. We parametrize the mass-ratio distribution using both inversion and Markov-Chain Monte Carlo forward-modelling techniques, and find it to be skewed towards low-mass companions, peaking at q ≈ 0.2. While solar-type primaries exhibit a brown dwarf desert across short and intermediate periods, we find a small but statistically significant (2.6σ) population of extreme-mass-ratio companions (q < 0.1) to our intermediate-mass primaries. Across periods of 100-1500 d and at q > 0.1, we measure the binary fraction of current A/F primaries to be 15.4 per cent ± 1.4 per cent, though we find that a large fraction of the companions (21 per cent ± 6 per cent) are white dwarfs in post-mass-transfer systems with primaries that are now blue stragglers, some of which are the progenitors of Type Ia supernovae, barium stars, symbiotics, and related phenomena. Excluding these white dwarfs, we determine the binary fraction of original A/F primaries to be 13.9 per cent ± 2.1 per cent over the same parameter space. Combining our measurements with those in the literature, we find the binary fraction across these periods is a constant 5 per cent for primaries M1 < 0.8 M⊙, but then increases linearly with log M1, demonstrating that natal discs around more massive protostars M1 ≳ 1 M⊙ become increasingly more prone to fragmentation. Finally, we find the eccentricity distribution of the main-sequence pairs to be much less eccentric than the thermal distribution.
NASA Astrophysics Data System (ADS)
Li, Jiajia; Li, Rongxi; Zhao, Bangsheng; Guo, Hui; Zhang, Shuan; Cheng, Jinghua; Wu, Xiaoli
2018-04-01
The use of Micro-Laser Raman spectroscopy technology for quantitatively determining gas carbon isotope composition is presented. In this study, 12CO2 and 13CO2 were mixed with N2 at various molar fraction ratios to obtain Raman quantification factors (F12CO2 and F13CO2), which provide a theoretical basis for calculating the δ13C value. And the corresponding values were 0.523 (0 < C12CO2/CN2 < 2) and 1.11998 (0 < C13CO2/CN2 < 1.5) respectively. It has shown that the representative Raman peak area can be used for the determination of δ13C values within the relative errors range of 0.076% to 1.154% in 13CO2/12CO2 binary mixtures when F12CO2/F13CO2 is 0.466972625. In addition, measurement of δ13C values by Micro-Laser Raman analysis were carried out on natural CO2 gas from Shengli Oil-field at room temperature under different pressures. The δ13C values obtained by Micro-Laser Raman spectroscopy technology and Isotope Ratio Mass Spectrometry (IRMS) technology are in good agreement with each other, and the relative errors range of δ13C values is 1.232%-6.964%. This research provides a fundamental analysis tool for determining gas carbon isotope composition (δ13C values) quantitatively by using Micro-Laser Raman spectroscopy. Experiment of results demonstrates that this method has the potential for obtaining δ13C values in natural CO2 gas reservoirs.
NASA Astrophysics Data System (ADS)
Magnall, J. M.; Gleeson, S. A.; Blamey, N. J. F.; Paradis, S.; Luo, Y.
2016-11-01
At Macmillan Pass (YT, Canada), the hydrothermal vent complexes beneath two shale-hosted massive sulphide (SHMS) deposits (Tom, Jason) are well preserved within Late Devonian strata. These deposits provide a unique opportunity to constrain key geochemical parameters (temperature, salinity, pH, fO2, ΣS) that are critical for metal transport and deposition in SHMS systems, and to evaluate the interaction between hydrothermal fluids and the mudstone host rock. This has been achieved using a combination of detailed petrography, isotopic techniques (δ34S, δ13C and δ18O values), carbonate rare earth element analysis (LA-ICP-MS), fluid inclusion analysis (microthermometry, gas analysis via incremental crush fast scan mass spectrometry), and thermodynamic modelling. Two main paragenetic stages are preserved in both vent complexes: Stage 1 comprises pervasive ankerite alteration of the organic-rich mudstone host rock and crosscutting stockwork ankerite veining (±pyrobitumen, pyrite and quartz) and; Stage 2 consists of main stage massive sulphide (galena-pyrrhotite-pyrite ± chalcopyrite-sphalerite) and siderite (±quartz and barytocalcite) mineralisation. Co-variation of δ18O and δ13C values in ankerite can be described by temperature dependent fractionation and fluid rock interaction. Together with fluid inclusion microthermometry, this provides evidence of a steep thermal gradient (from 300 to ∼100 °C) over approximately 15 m stratigraphic depth, temporally and spatially constrained within the paragenesis of both vent complexes and developed under shallow lithostatic (<1 km; 250 bars) to hydrostatic (<400 m; 40 bars) conditions. There is evidence of mixing between diagenetic and hydrothermal fluids recorded in chondrite-normalised rare earth element (REE) profiles of ankerite and siderite. Middle REE enrichments and superchondritic Y/Ho ratios (>28), characteristic of diagenetic fluids, are coupled with positive europium anomalies and variable light REE depletion, which are more consistent with chloride complexation in hot (>250 °C) hydrothermal fluids. In this shallow sub-seafloor setting, thermal alteration of organic carbon in the immature, chemically reactive mudstones also had an important role in the evolution of fluid chemistry. Reduced sulphur generation via thermochemical reduction of Late Devonian seawater sulphate produced positive δ34S values in sulphide minerals (+7.5‰ to +19.5‰), coupled with a suite of volatile components (CO2, CH4, C1-C4 hydrocarbons, N2) trapped in Stage 2 quartz. Many of these geochemical features developed during the final stages of fluid ascent, in a system where the fluid cooled close to the site of mineralisation. Using this information, we have modelled the metal transporting capacity of the deep hydrothermal fluid, which even at modest salinities (6 wt.% NaCl) was high (≫100 ppm Pb, Zn), owing to the combined effects of high temperature and low pH (⩽4.5). Therefore in SHMS systems, enhanced geothermal gradients and rapid fluid ascent (with minimal fluid cooling) are considered to be the most important factors for transporting high concentrations of base metals to the site of mineralisation.
2012-01-01
Sterile stable isotope solutions of 1 13C phenylalanine (1 13C phe, 100 2mol/mL) and d5 phe (100 2mol/mL) were made in 0.45% saline and infused via the left...described by Stein et al. (15). The enrichments of phenylalanine from isolated fibrinogen were determined by gas chromatography mass spectrometry (GC MS...baseline of 5.5 T 0.3 to 4.3 T 0.3 g/ dL (P G 0.05) on day 1 but returned to baseline on day 2 and thereafter. Changes in plasma fibrinogen
Zehra, Siffeen; Shavez Khan, Mohammad; Ahmad, Iqbal; Arjmand, Farukh
2018-05-07
New tailored Cu(II) & Zn(II) metal-based antitumor drug entities were synthesized from substituted benzothiazole o‒vanillin Schiff base ligands. The complexes were thoroughly characterized by elemental analysis, spectroscopic studies {IR, 1 H & 13 C NMR, ESI-MS, EPR} and magnetic susceptibility measurements. The structure activity relationship (SAR) studies of benzothiazole Cu(II) & Zn(II) complexes having molecular formulas [C 30 H 22 CuN 5 O 7 S 2 ], [C 30 H 20 Cl 2 CuN 5 O 7 S 2 ], [C 30 H 20 CuF 2 N 5 O 7 S 2 ], [C 30 H 22 N 4 O 4 S 2 Zn], [C 30 H 20 Cl 2 N 4 O 4 S 2 Zn], and [C 30 H 20 F 2 N 5 O 7 S 2 Zn], with CT‒DNA were performed by employing absorption, emission titrations, and hydrodynamic measurements. The DNA binding affinity was quantified by K b and K sv values which gave higher binding propensity for chloro-substituted Cu(II) [C 30 H 20 Cl 2 CuN 5 O 7 S 2 ] complex, suggestive of groove binding mode with subtle partial intercalation. Molecular properties and drug likeness profile were assessed for the ligands and all the Lipinski's rules were found to be obeyed. The antimicrobial potential of ligands and their Cu(II) & Zn(II) complexes were screened against some notably important pathogens viz., E. coli, S. aureus, P. aeruginosa, B. subtilis, and C. albicans. The cytotoxicity of the complexes [C 30 H 20 Cl 2 CuN 5 O 7 S 2 ], [C 30 H 20 CuF 2 N 5 O 7 S 2 ], [C 30 H 20 Cl 2 N 4 O 4 S 2 Zn], and [C 30 H 20 F 2 N 5 O 7 S 2 Zn] were evaluated against five human cancer cell lines viz., MCF‒7 (breast), MIA‒PA‒CA‒2 (pancreatic), HeLa (cervix) and Hep‒G2 (Hepatoma) and A498 (Kidney) by SRB assay which revealed that chloro-substituted [C 30 H 20 Cl 2 CuN 5 O 7 S 2 ] complex, exhibited pronounced specific cytotoxicity with GI 50 value of 4.8 μg/ml against HeLa cell line. Molecular docking studies were also performed to explore the binding modes and orientation of the complexes in the DNA helix.
Low temperature structures of dCpG-proflavine. Conformational and hydration effects.
Schneider, B; Ginell, S L; Berman, H M
1992-01-01
The structure of the complex of dCpG with proflavine was determined using x-ray data taken at -130 degrees C (low temperature) and at -2 degrees C (cold temperature) and compared with the structure of the complex determined previously at room temperature (Shieh, H. S., H. M. Berman, M. Dabrow, and S. Neidle. 1980. Nucleic Acids Res. 8:85-97). Low temperature was refined with 5,125 reflections between 8.0 and 0.93 A, Anisotropically modeled temperature factors were used for DNA/drug atoms and isotropic ones for water oxygens to R factor of 12.2% in P2(1)2(1)2; a = 32.853, b = 21.760, c = 13.296 A. Cold temperature was refined isotropically with 2,846 reflections 8.0-0.89 A to R = 15.1% in P2(1)2(1)2; a = 32.867, b = 22.356, c = 13.461 A. Both structures are very similar to the room temperature one, though some important differences were observed: one guanine sugar moiety is disordered and additional water molecules have been located that give rise to infinite polyhedral hydration networks. Images FIGURE 2 PMID:1489914
Gravitational radiation, inspiraling binaries, and cosmology
NASA Technical Reports Server (NTRS)
Chernoff, David F.; Finn, Lee S.
1993-01-01
We show how to measure cosmological parameters using observations of inspiraling binary neutron star or black hole systems in one or more gravitational wave detectors. To illustrate, we focus on the case of fixed mass binary systems observed in a single Laser Interferometer Gravitational-wave Observatory (LIGO)-like detector. Using realistic detector noise estimates, we characterize the rate of detections as a function of a threshold SNR Rho(0), H0, and the binary 'chirp' mass. For Rho(0) = 8, H0 = 100 km/s/Mpc, and 1.4 solar mass neutron star binaries, the sample has a median redshift of 0.22. Under the same assumptions but independent of H0, a conservative rate density of coalescing binaries implies LIGO will observe about 50/yr binary inspiral events. The precision with which H0 and the deceleration parameter q0 may be determined depends on the number of observed inspirals. For fixed mass binary systems, about 100 observations with Rho(0) = 10 in the LIGO will give H0 to 10 percent in an Einstein-DeSitter cosmology, and 3000 will give q0 to 20 percent. For the conservative rate density of coalescing binaries, 100 detections with Rho(0) = 10 will require about 4 yrs.
Hot gas, regenerative, supported H.sub.2 S sorbents
NASA Technical Reports Server (NTRS)
Voecks, Gerald E. (Inventor); Sharma, Pramod K. (Inventor)
1993-01-01
Efficient, regenerable sorbents for removal of H.sub.2 S from moderately high temperature (usually 200.degree. C.-550.degree.C.) gas streams comprise a porous, high surface area aluminosilicate support, suitably a zeolite, and most preferably a sodium deficient zeolite containing 1 to 20 weight percent of binary metal oxides. The binary oxides are a mixture of a Group VB or VIB metal oxide with a Group IB, IIB or VIII metal oxide such as V-Zn-O, V-Cu-O, Cu-Mo-O, Zn-Mo-O or Fe-Mo-O contained in the support. The sorbent effectively removes H.sub.2 S from the host gas stream in high efficiency and can be repetitively regenerated at least 10 times without loss of activity.
Lipid metabolites with free-radical scavenging activity from Euphorbia helioscopia L.
Cateni, F; Zilic, J; Altieri, T; Zacchigna, M; Procida, G; Gaggeri, R; Rossi, D; Collina, S
2014-07-01
The methanolic extract of the plant Euphorbia helioscopia L. exhibited an interesting free-radical scavenging activity. From the aerial parts of Euphorbia helioscopia L. (Euphorbiaceae), a complex mixture of seven cerebrosides together with glucoclionasterol, a digalactosyldiacylglycerol and a diacylmonogalactosylglycerol were identified. The structures of the cerebrosides were characterized as 1-O-β-D-glucosides of phytosphingosines, which comprised (2S, 3S, 4E, 8E)-2-amino-4(E),8(E)-octadecadiene-1,3-diol, (2S, 3S, 4E, 8Z)-2-amino-4(E),8(Z)-octadecadiene-1,3-diol, (2S, 3S, 4R, 8Z)-2-amino-8(Z)-octadecene-1,3,4-triol as long chain bases with seven 2-hydroxy fatty acids of varying chain lengths (C16, C24:1, C26:1, C24, C26, C28:1) linked to the amino group. The glycosylglycerides were characterized as (2S)-2,3-O-di-(9,12,15-octadecatrienoyl)-glyceryl-6-O-(α-D-galactopyranosyl)-β-D-galactopyranoside and (2S)-2,3-O-di-(9,12,15-octadecatrienoyl)-glyceryl-1-O-β-D-galactopyranoside. The structures were established on the basis of spectroscopic data and chemical reactions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Isab, Anvarhusein A.; Wazeer, Mohamed I. M.
2006-09-01
Complexation of Ag + with captopril, 1-[(2 S)-3-mercapto-2-methylpropionyl]- L-proline, has been studied by 1H and 13C-NMR spectroscopy. The equilibrium constants for the trans to cis isomers of captopril bound to Ag + were measured by 1H NMR spectroscopy. It is observed that the trans isomer of the drug binds more strongly to Ag + between pH 5 and 8, as shown by the broadening of the trans isomer's resonances in 13C NMR spectra on complexation. A monodentate complexation of the trans captopril with Ag + via the thiol site is proposed based on the solid-state NMR and IR data. A superior antimicrobial activity is exhibited by the Cap-Ag(I) complex compared to captopril ligand itself against Heterotrotropic Plate Counts (HPC), Pseudomonas aeruginosa and Fecal streptococcus bacteria.
Investigation of waste heat recovery of binary geothermal plants using single component refrigerants
NASA Astrophysics Data System (ADS)
Unverdi, M.
2017-08-01
In this study, the availability of waste heat in a power generating capacity of 47.4 MW in Germencik Geothermal Power Plant has been investigated via binary geothermal power plant. Refrigerant fluids of 7 different single components such as R-134a, R-152a, R-227ea, R-236fa, R-600, R-143m and R-161 have been selected. The binary cycle has been modeled using the waste heat equaling to mass flow rate of 100 kg/s geothermal fluid. While the inlet temperature of the geothermal fluid into the counter flow heat exchanger has been accepted as 110°C, the outlet temperature has been accepted as 70°C. The inlet conditions have been determined for the refrigerants to be used in the binary cycle. Finally, the mass flow rate of refrigerant fluid and of cooling water and pump power consumption and power generated in the turbine have been calculated for each inlet condition of the refrigerant. Additionally, in the binary cycle, energy and exergy efficiencies have been calculated for 7 refrigerants in the availability of waste heat. In the binary geothermal cycle, it has been found out that the highest exergy destruction for all refrigerants occurs in the heat exchanger. And the highest and lowest first and second law efficiencies has been obtained for R-600 and R-161 refrigerants, respectively.
Astone, Pia; Weinstein, Alan; Agathos, Michalis; Bejger, Michał; Christensen, Nelson; Dent, Thomas; Graff, Philip; Klimenko, Sergey; Mazzolo, Giulio; Nishizawa, Atsushi; Robinet, Florent; Schmidt, Patricia; Smith, Rory; Veitch, John; Wade, Madeline; Aoudia, Sofiane; Bose, Sukanta; Calderon Bustillo, Juan; Canizares, Priscilla; Capano, Colin; Clark, James; Colla, Alberto; Cuoco, Elena; Da Silva Costa, Carlos; Dal Canton, Tito; Evangelista, Edgar; Goetz, Evan; Gupta, Anuradha; Hannam, Mark; Keitel, David; Lackey, Benjamin; Logue, Joshua; Mohapatra, Satyanarayan; Piergiovanni, Francesco; Privitera, Stephen; Prix, Reinhard; Pürrer, Michael; Re, Virginia; Serafinelli, Roberto; Wade, Leslie; Wen, Linqing; Wette, Karl; Whelan, John; Palomba, C; Prodi, G
The Amaldi 10 Parallel Session C2 on gravitational wave (GW) search results, data analysis and parameter estimation included three lively sessions of lectures by 13 presenters, and 34 posters. The talks and posters covered a huge range of material, including results and analysis techniques for ground-based GW detectors, targeting anticipated signals from different astrophysical sources: compact binary inspiral, merger and ringdown; GW bursts from intermediate mass binary black hole mergers, cosmic string cusps, core-collapse supernovae, and other unmodeled sources; continuous waves from spinning neutron stars; and a stochastic GW background. There was considerable emphasis on Bayesian techniques for estimating the parameters of coalescing compact binary systems from the gravitational waveforms extracted from the data from the advanced detector network. This included methods to distinguish deviations of the signals from what is expected in the context of General Relativity.
NASA Technical Reports Server (NTRS)
Astone, Pia; Weinstein, Alan; Agathos, Michalis; Bejger, Michal; Christensen, Nelson; Dent, Thomas; Graff, Philip; Klimenko, Sergey; Mazzolo, Giulio; Nishizawa, Atsushi
2015-01-01
The Amaldi 10 Parallel Session C2 on gravitational wave(GW) search results, data analysis and parameter estimation included three lively sessions of lectures by 13 presenters, and 34 posters. The talks and posters covered a huge range of material, including results and analysis techniques for ground-based GW detectors, targeting anticipated signals from different astrophysical sources: compact binary inspiral, merger and ringdown; GW bursts from intermediate mass binary black hole mergers, cosmic string cusps, core-collapse supernovae, and other unmodeled sources; continuous waves from spinning neutron stars; and a stochastic GW background. There was considerable emphasis on Bayesian techniques for estimating the parameters of coalescing compact binary systems from the gravitational waveforms extracted from the data from the advanced detector network. This included methods to distinguish deviations of the signals from what is expected in the context of General Relativity.
Low temperature structures of dCpG-proflavine.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneider, B.; Ginell, S. L.; Berman, H. M.
1992-12-01
The structure of the complex of dCpG with proflavine was determined using x-ray data taken at -130 degrees C (low temperature) and at -2 degrees C (cold temperature) and compared with the structure of the complex determined previously at room temperature (Shieh, H. S., H. M. Berman, M. Dabrow, and S. Neidle. 1980. Nucleic Acids Res. 8:85-97). Low temperature was refined with 5,125 reflections between 8.0 and 0.93 A, Anisotropically modeled temperature factors were used for DNA/drug atoms and isotropic ones for water oxygens to R factor of 12.2% in P2(1)2(1)2; a = 32.853, b = 21.760, c = 13.296more » A. Cold temperature was refined isotropically with 2,846 reflections 8.0-0.89 A to R = 15.1% in P2(1)2(1)2; a = 32.867, b = 22.356, c = 13.461 A. Both structures are very similar to the room temperature one, though some important differences were observed: one guanine sugar moiety is disordered and additional water molecules have been located that give rise to infinite polyhedral hydration networks.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mohan, Sepuru K., E-mail: mohansepuri@gmail.com; Gupta, Arun A., E-mail: ninja14gupta@gmail.com; Yu, Chin, E-mail: cyu.nthu@gmail.com
2013-05-03
Highlights: •The halo human S100A6 (C3S) NMR chemical shifts were assigned. •The interactions between S100A6m and RAGE V domain was investigated by ITC. •The residues involved in the S100A6m–RAGE V domain binding were mapped by {sup 1}H–{sup 15}N HSQC titration. •S100A6–RAGE V domain tetrameric complex model was generated from NMR studies. •The S100A6–RAGE V domain interface regions were elucidated based on HADDOCK model. -- Abstract: S100A6 is involved in several vital biological functions, such as calcium sensing and cell proliferation. It is a homodimeric protein that belongs to the S100 protein family. The receptor for advanced glycation end products (RAGE)more » has been shown to play a role in the progression of various disease conditions, such as diabetes and immune/inflammatory disorders. Information regarding the association of RAGE with S100 proteins at a molecular level is useful to understand the diversity of the RAGE signaling pathways. In this report, biomolecular NMR techniques were utilized for the resonance assignment of the C3S mutation in human S100A6 and characterizing its interaction with the RAGE V domain. Further binding affinity between S100A6m and the RAGE V domain was determined by isothermal titration calorimetric studies. HADDOCK was used to generate a heterotetramer model of the S100A6m–RAGE V domain complex. This model provides an important insights into the S100–RAGE cellular signaling pathway.« less
Li, Jiajia; Li, Rongxi; Zhao, Bangsheng; Guo, Hui; Zhang, Shuan; Cheng, Jinghua; Wu, Xiaoli
2018-04-15
The use of Micro-Laser Raman spectroscopy technology for quantitatively determining gas carbon isotope composition is presented. In this study, 12 CO 2 and 13 CO 2 were mixed with N 2 at various molar fraction ratios to obtain Raman quantification factors (F 12CO2 and F 13CO2 ), which provide a theoretical basis for calculating the δ 13 C value. And the corresponding values were 0.523 (0
Electronically Strongly Coupled Divinylheterocyclic-Bridged Diruthenium Complexes.
Pfaff, Ulrike; Hildebrandt, Alexander; Korb, Marcus; Oßwald, Steffen; Linseis, Michael; Schreiter, Katja; Spange, Stefan; Winter, Rainer F; Lang, Heinrich
2016-01-11
Complexes [{Ru(CO)Cl(PiPr3 )2 }2 (μ-2,5-(CH-CH)2 -(c) C4 H2 E] (E=NR; R=C6 H4 -4-NMe2 (10 a), C6 H4 -4-OMe (10 b), C6 H4 -4-Me (10 c), C6 H5 (10 d), C6 H4 -4-CO2 Et (10 e), C6 H4 -4-NO2 (10 f), C6 H3 -3,5-(CF3 )2 (10 g), CH3 (11); E=O (12), S (13)) are discussed. The solid state structures of four alkynes and two complexes are reported. (Spectro)electrochemical studies show a moderate influence of the nature of the heteroatom and the electron-donating or -withdrawing substituents R in 10 a-g on the electrochemical and spectroscopic properties. The CVs display two consecutive one-electron redox events with ΔE°'=350-495 mV. A linear relationship between ΔE°' and the σp Hammett constant for 10 a-f was found. IR, UV/Vis/NIR and EPR studies for 10(+) -13(+) confirm full charge delocalization over the {Ru}CH-CH-heterocycle-CH-CH{Ru} backbone, classifying them as Class III systems according to the Robin and Day classification. DFT-optimized structures of the neutral complexes agree well with the experimental ones and provide insight into the structural consequences of stepwise oxidations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
77 FR 50704 - National Institute on Aging; Notice of Closed Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
..., Drug Development for Alzheimer's Disease. Date: September 13, 2012. Time: 1:00 p.m. to 2:00 p.m. Agenda... U.S.C. App.), notice is hereby given of the following meetings. The meetings will be closed to the public in accordance with the provisions set forth in sections 552b(c)(4) and 552b(c)(6), Title 5 U.S.C...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ballato, John
One binary and three series of ternary non-oxide pure sulfide glasses compositions were investigated with the goal of synthesizing new glasses that exhibit high glass transition (Tg) and crystallization (Tc) temperatures, infrared transparency, and reliable glass formability. The binary glass series consisted of Ges 2 and La 2S 3 and the three glass series in the x(nBaS + mLa2S3) + (1-2x)GeS2 ternary system have BaS:La2S3 modifier ratios of 1:1, 1:2, and 2:1 with . With these glasses, new insights were realized as to how ionic glasses form and how glass modifiers affect both structure and glass formability. All synthesized compositionsmore » were characterized by Infrared (IR) and Raman spectroscopies and differential thermal analysis (DTA) to better understand the fundamental structure, optical, and thermal characteristics of the glasses. After a range of these glasses were synthesized, optimal compositions were formed into glass disks and subjected to gamma irradiation. Glass disks were characterized both before and after irradiation by microscope imaging, measuring the refractive index, density, and UV-VIS-IR transmission spectra. The final total dose the samples were subjected to was ~2.5 MGy. Ternary samples showed a less than 0.4% change in density and refractive index and minimal change in transmission window. The glasses also resisted cracking as seen in microscope images. Overall, many glass compositions were developed that possess operating temperatures above 500 °C, where conventional chalcogenide glasses such as As2S3 and have T gs from ~200-300 °C, and these glasses have a greater than Tc – Tg values larger than 100 °C and this shows that these glasses have good thermal stability of Tg such that they can be fabricated into optical fibers and as such can be considered candidates for high temperature infrared fiber optics. Initial fiber fabrication efforts showed that selected glasses could be drawn but larger samples would be needed for further development and optimization« less
A young contracting white dwarf in the peculiar binary HD 49798/RX J0648.0-4418?
NASA Astrophysics Data System (ADS)
Popov, S. B.; Mereghetti, S.; Blinnikov, S. I.; Kuranov, A. G.; Yungelson, L. R.
2018-02-01
HD 49798/RX J0648.0-4418 is a peculiar X-ray binary with a hot subdwarf (sdO) mass donor. The nature of the accreting compact object is not known, but its spin period P = 13.2 s and \\dot{P} =-2.15 × 10^{-15} s s-1 proves that it can be only either a white dwarf or a neutron star. The spin-up has been very stable for more than 20 yr. We demonstrate that the continuous stable spin-up of the compact companion of HD 49798 can be best explained by contraction of a young white dwarf with an age ˜2 Myr. This allows us to interpret all the basic parameters of the system in the framework of an accreting white dwarf. We present examples of binary evolution, which result in such systems. If correct, this is the first direct evidence for a white dwarf contraction in early evolutionary stages.
Khammanivong, Ali; Wang, Chengxing; Sorenson, Brent S.; Ross, Karen F.; Herzberg, Mark C.
2013-01-01
Malignant transformation results in abnormal cell cycle regulation and uncontrolled growth in head and neck squamous cell carcinoma (HNSCC) and other cancers. S100A8/A9 (calprotectin) is a calcium-binding heterodimeric protein complex implicated in cell cycle regulation, but the specific mechanism and role in cell cycle control and carcinoma growth are not well understood. In HNSCC, S100A8/A9 is downregulated at both mRNA and protein levels. We now report that downregulation of S100A8/A9 correlates strongly with a loss of cell cycle control and increased growth of carcinoma cells. To show its role in carcinogenesis in an in vitro model, S100A8/A9 was stably expressed in an S100A8/A9-negative human carcinoma cell line (KB cells, HeLa-like). S100A8/A9 expression increases PP2A phosphatase activity and p-Chk1 (Ser345) phosphorylation, which appears to signal inhibitory phosphorylation of mitotic p-Cdc25C (Ser216) and p-Cdc2 (Thr14/Tyr15) to inactivate the G2/M Cdc2/cyclin B1 complex. Cyclin B1 expression then downregulates and the cell cycle arrests at the G2/M checkpoint, reducing cell division. As expected, S100A8/A9-expressing cells show both decreased anchorage-dependent and -independent growth and mitotic progression. Using shRNA, silencing of S100A8/A9 expression in the TR146 human HNSCC cell line increases growth and survival and reduces Cdc2 inhibitory phosphorylation at Thr14/Tyr15. The level of S100A8/A9 endogenous expression correlates strongly with the reduced p-Cdc2 (Thr14/Tyr14) level in HNSCC cell lines, SCC-58, OSCC-3 and UMSCC-17B. S100A8/A9-mediated control of the G2/M cell cycle checkpoint is, therefore, a likely suppressive mechanism in human squamous cell carcinomas and may suggest new therapeutic approaches. PMID:23874958
Vujić, Jelena M; Cvijović, Milica; Kaluderović, Goran N; Milovanović, Marija; Zmejkovski, Bojana B; Volarević, Vladislav; Arsenijević, Nebojsa; Sabo, Tibor J; Trifunović, Srećko R
2010-09-01
Four novel bidentate N,N'-ligand precursors, including O,O'-dialkyl esters (alkyl = ethyl, n-propyl, n-butyl and n-pentyl), L1 x 2 HCl-L4 x 2 HCl, of (S,S)-ethylenediamine-N,N'-di-2-(4-methyl)-pentanoic acid dihydrochloride [(S,S)-H(4)eddl]Cl(2) and the corresponding palladium(II) complexes 1-4, were prepared and characterized by IR, (1)H NMR and (13)C NMR spectroscopy and elemental analysis. In vitro cytotoxicity of all compounds was determined against chronic lymphocytic leukemia cells (CLL). The compounds were found to exhibit higher antitumoral activity than cisplatin. The most active compound 2, [PdCl(2){(S,S)-nPr(2)eddl}], was found to be 13.6 times more active than cisplatin on CLL cells. 2010 Elsevier Masson SAS. All rights reserved.
Scandium complexes with the tetraphenylethylene and anthracene dianions.
Ellis, John E; Minyaev, Mikhail E; Nifant'ev, Ilya E; Churakov, Andrei V
2018-06-01
The structural study of Sc complexes containing dianions of anthracene and tetraphenylethylene should shed some light on the nature of rare-earth metal-carbon bonding. The crystal structures of (18-crown-6)bis(tetrahydrofuran-κO)sodium bis(η 6 -1,1,2,2-tetraphenylethenediyl)scandium(III) tetrahydrofuran disolvate, [Na(C 4 H 8 O) 2 (C 12 H 24 O 6 )][Sc(C 26 H 20 ) 2 ]·2C 4 H 8 O or [Na(18-crown-6)(THF) 2 ][Sc(η 6 -C 2 Ph 4 ) 2 ]·2(THF), (1b), (η 5 -1,3-diphenylcyclopentadienyl)(tetrahydrofuran-κO)(η 6 -1,1,2,2-tetraphenylethenediyl)scandium(III) toluene hemisolvate, [Sc(C 17 H 13 )(C 26 H 20 )(C 4 H 8 O)]·0.5C 7 H 8 or [(η 5 -1,3-Ph 2 C 5 H 3 )Sc(η 6 -C 2 Ph 4 )(THF)]·0.5(toluene), (5b), poly[[(μ 2 -η 3 :η 3 -anthracenediyl)bis(η 6 -anthracenediyl)bis(η 5 -1,3-diphenylcyclopentadienyl)tetrakis(tetrahydrofuran)dipotassiumdiscandium(III)] tetrahydrofuran monosolvate], {[K 2 Sc 2 (C 14 H 10 ) 3 (C 17 H 13 ) 2 (C 4 H 8 O) 4 ]·C 4 H 8 O} n or [K(THF) 2 ] 2 [(1,3-Ph 2 C 5 H 3 ) 2 Sc 2 (C 14 H 10 ) 3 ]·THF, (6), and 1,4-diphenylcyclopenta-1,3-diene, C 17 H 14 , (3a), have been established. The [Sc(η 6 -C 2 Ph 4 ) 2 ] - complex anion in (1b) contains the tetraphenylethylene dianion in a symmetrical bis-η 3 -allyl coordination mode. The complex homoleptic [Sc(η 6 -C 2 Ph 4 ) 2 ] - anion retains its structure in THF solution, displaying hindered rotation of the coordinated phenyl rings. The 1D 1 H and 13 C{ 1 H}, and 2D COSY 1 H- 1 H and 13 C- 1 H NMR data are presented for M[Sc(Ph 4 C 2 ) 2 ]·xTHF [M = Na and x = 4 for (1a); M = K and x = 3.5 for (2a)] in THF-d 8 media. Complex (5b) exhibits an unsymmetrical bis-η 3 -allyl coordination mode of the dianion, but this changes to a η 4 coordination mode for (1,3-Ph 2 C 5 H 3 )Sc(Ph 4 C 2 )(THF) 2 , (5a), in THF-d 8 solution. A 45 Sc NMR study of (2a) and UV-Vis studies of (1a), (2a) and (5a) indicate a significant covalent contribution to the Sc-Ph 4 C 2 bond character. The unique Sc ate complex, (6), contains three anthracenide dianions demonstrating both a η 6 -coordination mode for two bent ligands and a μ 2 -η 3 :η 3 -bridging mode of a flat ligand. Each [(1,3-Ph 2 C 5 H 3 ) 2 Sc 2 (C 14 H 10 ) 3 ] 2- dianionic unit is connected to four neighbouring units via short contacts with [K(THF) 2 ] + cations, forming a two-dimensional coordination polymer framework parallel to (001).
Inhibition of emesis by tachykinin NK1 receptor antagonists in Suncus murinus (house musk shrew).
Rudd, J A; Ngan, M P; Wai, M K
1999-02-05
The anti-emetic potential of CP-122,721 ((+)-2S,3S)-3-(2-methoxy-5-trifluoromethoxybenzyl)amino-2-phenylpi peridine), CP-99,994 ((+)-(2S,3S)-3-(2-methoxybenzylamino)-2-phenylpiperidine), CP-100,263 ((-)-(2R,3R)-3-(2-methoxybenzylamino)-2-phenylpiperidine), RP 67580 ((3R, 7aR)-7,7-diphenyl-2-[1-imino-2-(2-methoxyphenyl)ethyl] po-hydroisoindol-4-one), FK 888 (N2-[(4R)-4-hydroxy-1-(1-methyl-1H-in-dole-3-yl)carbonyl-L-propyl] -N-methyl-N-phenylmethyl-1-3-(2-naphthyl)-alaninamide) and GR 82334 ([D-Pro9[spiro-g-lactam]Leu10]-physalaemin-(1-11)) was investigated to inhibit nicotine (5 mg/kg, s.c.)-, copper sulphate pentahydrate (120 mg/kg, intragastric)- and motion (4 cm horizontal displacement at 1 Hz for 5 min)-induced emesis in Suncus murinus. A 30 min intraperitoneal pre-treatment with CP-122,721, CP-99,994, RP 67580 and FK 888 significantly (P < 0.05) antagonized nicotine-induced emesis with ID50 values of 2.1, 2.3, 13.5 and 19.2 mg/kg, respectively CP-100,263, the less active enantiomer of CP-99,994, was inactive at doses up to 10 mg/kg. Infusion of GR 82334, CP-122,721, CP-99,994 and FK 888 into the dorsal vagal complex of the hindbrain also antagonized nicotine-induced emesis yielding ID50 values of 1.1, 3.0, 3.3 and 58.0 microg/dorsal vagal complex, respectively RP 67580 and CP-100,263 were inactive. RP 67580 and FK 888 failed to antagonize copper sulphate-induced emesis but CP-122,721 and CP-99,994 were active yielding ID50 values of 2.2 and 3.0 mg/kg, i.p., respectively. CP-99,994 also completely prevented motion-induced emesis at 10 mg/kg, i.p. (P < 0.05) and RP 67580 produced a significant reduction of motion-induced emesis at 10 mg/kg, i.p. (P < 0.05). These studies provide evidence of a central site of action of tachykinin NK1 receptor antagonists to inhibit nicotine-induced emesis in S. murinus and confirm the broad profile of inhibitory action. The rank order of potency of the antagonists following the intra-dorsal vagal complex administration suggests that the S. murinus tachykinin NK1 receptor has a unique pharmacological profile.
Pintus, Anna; Aragoni, M Carla; Cinellu, Maria A; Maiore, Laura; Isaia, Francesco; Lippolis, Vito; Orrù, Germano; Tuveri, Enrica; Zucca, Antonio; Arca, Massimiliano
2017-05-01
The novel heteroleptic cyclometalated complex [Au III (py b -H)(mnt)] (1; py b -H=C-deprotonated 2-benzylpyridine; mnt =1,2-dicyanoethene-1,2-dithiolate) was tested against a panel of ten Gram positive (belonging to the Staphylococcus, Streptococcus spp. and Bacillus clausii), Gram negative (E. coli, K. pneumoniae, P. aeruginosa) bacteria and three yeasts belonging to the Candida spp. Complex 1 showed a remarkable bacteriostatic antimicrobial activity against staphylococci, with Minimum Inhibitory Concentration (MIC) values of 1.56 and 3.13μg/mL for S. haemoliticus and S. aureus, respectively. Spectroscopic and electrochemical measurements, supported by Density Functional Theory (DFT) calculations, were exploited to fully investigate the electronic structure of complex 1 and its relationship with the antimicrobial activity. Copyright © 2017 Elsevier Inc. All rights reserved.
Is There a Circumbinary Planet around NSVS 14256825?
NASA Astrophysics Data System (ADS)
Nasiroglu, Ilham; Goździewski, Krzysztof; Słowikowska, Aga; Krzeszowski, Krzysztof; Żejmo, Michał; Zola, Staszek; Er, Huseyin; Ogłoza, Waldemar; Dróżdż, Marek; Koziel-Wierzbowska, Dorota; Debski, Bartlomiej; Karaman, Nazli
2017-03-01
The cyclic behavior of (O-C) residuals of eclipse timings in the sdB+M eclipsing binary NSVS 14256825 was previously attributed to one or two Jovian-type circumbinary planets. We report 83 new eclipse timings that not only fill in the gaps in those already published but also extend the time span of the (O-C) diagram by three years. Based on the archival and our new data spanning over more than 17 years, we re-examined the up-to-date system (O-C). The data revealed a systematic, quasi-sinusoidal variation deviating from an older linear ephemeris by about 100 s. It also exhibits a maximum in the (O-C) near JD 2,456,400 that was previously unknown. We consider two most credible explanations of the (O-C) variability: the light propagation time due to the presence of an invisible companion in a distant circumbinary orbit, and magnetic cycles reshaping one of the binary components, known as the Applegate or Lanza-Rodonó effect. We found that the latter mechanism is unlikely due to the insufficient energy budget of the M-dwarf secondary. In the framework of the third-body hypothesis, we obtained meaningful constraints on the Keplerian parameters of a putative companion and its mass. Our best-fitting model indicates that the observed quasi-periodic (O-C) variability can be explained by the presence of a brown dwarf with the minimal mass of 15 Jupiter masses rather than a planet, orbiting the binary in a moderately elliptical orbit (e≃ 0.175) with a period of ˜10 years. Our analysis rules out the two-planet model proposed earlier.
An Astrometric Analysis of eta Carinae’s Eruptive History Using HST WF/PC2 and ACS Observations
2007-07-11
Std Z39-18 to address the question of binarity. Based on an astrometric analysis of the data, binary reflex motion is detected in the primary and, by...Measurement Results 96 5.1 Primary Luminosity and Mass . . . . . . . . . . . . . . . . . . . . . . 96 5.2 Secondary Mass and Luminosity...Binary Models . . . . . . . . . . . 100 5.5 Primary –Secondary Distance . . . . . . . . . . . . . . . . . . . . . . . 102 5.6 Periastron passage
Stieg, David C.; Willis, Stephen D.; Ganesan, Vidyaramanan; Ong, Kai Li; Scuorzo, Joseph; Song, Mia; Grose, Julianne; Strich, Randy; Cooper, Katrina F.
2018-01-01
In response to oxidative stress, cells decide whether to mount a survival or cell death response. The conserved cyclin C and its kinase partner Cdk8 play a key role in this decision. Both are members of the Cdk8 kinase module, which, with Med12 and Med13, associate with the core mediator complex of RNA polymerase II. In Saccharomyces cerevisiae, oxidative stress triggers Med13 destruction, which thereafter releases cyclin C into the cytoplasm. Cytoplasmic cyclin C associates with mitochondria, where it induces hyperfragmentation and regulated cell death. In this report, we show that residues 742–844 of Med13’s 600–amino acid intrinsic disordered region (IDR) both directs cyclin C-Cdk8 association and serves as the degron that mediates ubiquitin ligase SCFGrr1-dependent destruction of Med13 following oxidative stress. Here, cyclin C-Cdk8 phosphorylation of Med13 most likely primes the phosphodegron for destruction. Next, pro-oxidant stimulation of the cell wall integrity pathway MAP kinase Slt2 initially phosphorylates cyclin C to trigger its release from Med13. Thereafter, Med13 itself is modified by Slt2 to stimulate SCFGrr1-mediated destruction. Taken together, these results support a model in which this IDR of Med13 plays a key role in controlling a molecular switch that dictates cell fate following exposure to adverse environments. PMID:29212878
HITRANonline: a New Structure and Interface for HITRAN Line Lists and Cross Sections
NASA Astrophysics Data System (ADS)
Hill, Christian; Rothman, Laurence S.; Gordon, Iouli E.; Kochanov, Roman V.; Wcislo, Piotr; Wilzewski, Jonas
2015-06-01
We present HITRANonline, an online interface to the internationally-recognised HITRAN molecular spectroscopic database[1], and describe the structure of its relational database backend[2]. As the amount and complexity of spectroscopic data on molecules used in atmospheric modelling has increased, the existing 160-character, text-based format has become inadequate for its description. For example, line shapes such as the Hartmann-Tran profile[3] require up to six parameters for their full description (each with uncertainties and references), data is available on line-broadening by species other than ``air'' and ``self'' and more than the current maximum of 10 isotopologues of some molecules (for example, CO_2) can be important for accurate radiative-transfer modelling. The new relational database structure overcomes all of these limitations as well as allowing for better data provenance through ``timestamping'' of transitions and a direct link between items of data and their literature sources. To take full advantage of this new database structure, the online interface HITRANonline, available at www.hitran.org, provides a user-friendly way to make queries of HITRAN data with the option of returning it in a customizable format with user-defined fields and precisions. Binary formats such as HDF-5 are also supported. In addition to the data, each query also produces its own bibliography (in HTML and BibTeX formats), ``README'' documentation and interactive graph for easy visualization. L. S. Rothman et al., JSQRT 130, 4-50 (2013). C. Hill, I. E. Gordon, L. S. Rothman, J. Tennyson, JQSRT130, 51-61 (2013). N. H. Ngo, D. Lisak, H. Tran, J.-M. Hartmann, JQSRT 129, 89--100, (2013); erratum: JQSRT 134, 105 (2014). This work has been supported by NASA Aura Science Team Grant NNX14AI55G and NASA Planetary Atmospheres Grant NNX13AI59G.
NASA Astrophysics Data System (ADS)
Fabian, Andrew C.; Pounds, Kenneth A.; Blandford, Roger D.
2004-07-01
Preface; 1. Forty years on from Aerobee 150: a personal perspective K. Pounds; 2. X-ray spectroscopy of astrophysical plasmas S. M. Kahn, E. Behar, A. Kinkhabwala and D. W. Savin; 3. X-rays from stars M. Gudel; 4. X-ray observations of accreting white-dwarf systems M. Cropper, G. Ramsay, C. Hellier, K. Mukai, C. Mauche and D. Pandel; 5. Accretion flows in X-ray binaries C. Done; 6. Recent X-ray observations of supernova remnants C. R. Canizares; 7. Luminous X-ray sources in spiral and star-forming galaxies M. Ward; 8. Cosmological constraints from Chandra observations of galaxy clusters S. W. Allen; 9. Clusters of galaxies: a cosmological probe R. Mushotzky; 10. Obscured active galactic nuclei: the hidden side of the X-ray Universe G. Matt; 11. The Chandra Deep Field-North Survey and the cosmic X-ray background W. N. Brandt, D. M. Alexander, F. E. Bauer and A. E. Hornschemeier; 12. Hunting the first black holes G. Hasinger; 13. X-ray astronomy in the new millennium: a summary R. D. Blandford.
Trust and Decision Making: An Empirical Platform
2008-06-01
13th ICCRTS “C2 for Complex Endeavors” Trust and Decision Making : An Empirical Platform Topic(s): Cognitive and Social Issues...and Decision Making : An Empirical Platform 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e...PERSON a. REPORT unclassified b. ABSTRACT unclassified c. THIS PAGE unclassified Trust and Decision Making : An Empirical Platform Dr. Joseph B
Low-field thermal mixing in [1-(13)C] pyruvic acid for brute-force hyperpolarization.
Peat, David T; Hirsch, Matthew L; Gadian, David G; Horsewill, Anthony J; Owers-Bradley, John R; Kempf, James G
2016-07-28
We detail the process of low-field thermal mixing (LFTM) between (1)H and (13)C nuclei in neat [1-(13)C] pyruvic acid at cryogenic temperatures (4-15 K). Using fast-field-cycling NMR, (1)H nuclei in the molecule were polarized at modest high field (2 T) and then equilibrated with (13)C nuclei by fast cycling (∼300-400 ms) to a low field (0-300 G) that activates thermal mixing. The (13)C NMR spectrum was recorded after fast cycling back to 2 T. The (13)C signal derives from (1)H polarization via LFTM, in which the polarized ('cold') proton bath contacts the unpolarised ('hot') (13)C bath at a field so low that Zeeman and dipolar interactions are similar-sized and fluctuations in the latter drive (1)H-(13)C equilibration. By varying mixing time (tmix) and field (Bmix), we determined field-dependent rates of polarization transfer (1/τ) and decay (1/T1m) during mixing. This defines conditions for effective mixing, as utilized in 'brute-force' hyperpolarization of low-γ nuclei like (13)C using Boltzmann polarization from nearby protons. For neat pyruvic acid, near-optimum mixing occurs for tmix∼ 100-300 ms and Bmix∼ 30-60 G. Three forms of frozen neat pyruvic acid were tested: two glassy samples, (one well-deoxygenated, the other O2-exposed) and one sample pre-treated by annealing (also well-deoxygenated). Both annealing and the presence of O2 are known to dramatically alter high-field longitudinal relaxation (T1) of (1)H and (13)C (up to 10(2)-10(3)-fold effects). Here, we found smaller, but still critical factors of ∼(2-5)× on both τ and T1m. Annealed, well-deoxygenated samples exhibit the longest time constants, e.g., τ∼ 30-70 ms and T1m∼ 1-20 s, each growing vs. Bmix. Mixing 'turns off' for Bmix > ∼100 G. That T1m≫τ is consistent with earlier success with polarization transfer from (1)H to (13)C by LFTM.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ektarawong, A., E-mail: anekt@ifm.liu.se; Hultman, L.; Birch, J.
The elastic properties of alloys between boron suboxide (B{sub 6}O) and boron carbide (B{sub 13}C{sub 2}), denoted by (B{sub 6}O){sub 1−x}(B{sub 13}C{sub 2}){sub x}, as well as boron carbide with variable carbon content, ranging from B{sub 13}C{sub 2} to B{sub 4}C are calculated from first-principles. Furthermore, the mixing thermodynamics of (B{sub 6}O){sub 1−x}(B{sub 13}C{sub 2}){sub x} is studied. A superatom-special quasirandom structure approach is used for modeling different atomic configurations, in which effects of configurational disorder between the carbide and suboxide structural units, as well as between boron and carbon atoms within the units, are taken into account. Elastic propertiesmore » calculations demonstrate that configurational disorder in B{sub 13}C{sub 2}, where a part of the C atoms in the CBC chains substitute for B atoms in the B{sub 12} icosahedra, drastically increase the Young’s and shear modulus, as compared to an atomically ordered state, B{sub 12}(CBC). These calculated elastic moduli of the disordered state are in excellent agreement with experiments. Configurational disorder between boron and carbon can also explain the experimentally observed almost constant elastic moduli of boron carbide as the carbon content is changed from B{sub 4}C to B{sub 13}C{sub 2}. The elastic moduli of the (B{sub 6}O){sub 1−x}(B{sub 13}C{sub 2}){sub x} system are also practically unchanged with composition if boron-carbon disorder is taken into account. By investigating the mixing thermodynamics of the alloys, in which the Gibbs free energy is determined within the mean-field approximation for the configurational entropy, we outline the pseudo-binary phase diagram of (B{sub 6}O){sub 1−x}(B{sub 13}C{sub 2}){sub x}. The phase diagram reveals the existence of a miscibility gap at all temperatures up to the melting point. Also, the coexistence of B{sub 6}O-rich as well as ordered or disordered B{sub 13}C{sub 2}-rich domains in the material prepared through equilibrium routes is predicted.« less
Gumel, A M; Annuar, M S M; Heidelberg, T
2013-04-01
The effects of organic solvents and their binary mixture in the glucose functionalization of bacterial poly-3-hydroxyalkanoates catalyzed by Lecitase™ Ultra were studied. Equal volume binary mixture of DMSO and chloroform with moderate polarity was more effective for the enzyme catalyzed synthesis of the carbohydrate polymer at ≈38.2 (±0.8)% reactant conversion as compared to the mono-phasic and other binary solvents studied. The apparent reaction rate constant as a function of medium water activity (aw) was observed to increase with increasing solvent polarity, with optimum aw of 0.2, 0.4 and 0.7 (±0.1) observed in hydrophilic DMSO, binary mixture DMSO:isooctane and hydrophobic isooctane, respectively. Molecular sieve loading between 13 to 15gL(-1) (±0.2) and reaction temperature between 40 to 50°C were found optimal. Functionalized PHA polymer showed potential characteristics and biodegradability. Copyright © 2012 Elsevier B.V. All rights reserved.
Feng, Shu-Yan; Li, Wen-Xian; Guo, Feng; Cao, Xiao-Fang
2014-11-01
A novel ternary complex, Tb(2)L4 · L'·(ClO4)6 · 8H2O, has been synthesized using bis(benzylsulfinyl)methane as the first ligand L and 2,2'-dipyridyl as the second ligand L'. The ternary complex was characterized by element analysis, molar conductivity, coordination titration analysis, infrared, thermogravimetric-differential scanning calorimetric and ultraviolet spectra. The results indicated that the composition of the complex was Tb2 L4 · L'·(ClO4)6 · 8H2O (L = C(6)H(5)CH(2) SOCH(2)SOCH(2)C(6)H(5); L' = Dipy). Fourier transform infrared results revealed that the perchlorate group was bonded with the Tb(III) ion by the oxygen atom, and the coordination was bidentate. The fluorescent spectra illustrated that the complex displayed characteristic fluorescence in the solid state. After the introduction of the second ligand, 2,2-dipyridyl, the relative emission intensity and fluorescence lifetime of the ternary complex Tb(2)L(4) · L'·(ClO(4))(6) · 8H2O were enhanced compared to the binary complex TbL(2.5)(ClO4)3 · 3H2O. This indicated that the presence of both organic ligand bis(benzylsulfinyl)methane and the second ligand 2,2-dipyridyl could sensitize the fluorescence intensity of Tb(III) ion, and introduction of the 2,2-dipyridyl group resulted in an enhancement of the fluorescence of the Tb(III) ternary rare earth complex. The strongest characteristic fluorescence emission intensity of the ternary complex was 9.36 times that of the binary complex. The phosphorescence spectra and fluorescence lifetime of the complex were also measured. Copyright © 2014 John Wiley & Sons, Ltd.
Search for stopped Gluinos in pp collisions at square root s=7 TeV.
Khachatryan, V; Sirunyan, A M; Tumasyan, A; Adam, W; Bergauer, T; Dragicevic, M; Erö, J; Fabjan, C; Friedl, M; Frühwirth, R; Ghete, V M; Hammer, J; Hänsel, S; Hartl, C; Hoch, M; Hörmann, N; Hrubec, J; Jeitler, M; Kasieczka, G; Kiesenhofer, W; Krammer, M; Liko, D; Mikulec, I; Pernicka, M; Rohringer, H; Schöfbeck, R; Strauss, J; Taurok, A; Teischinger, F; Waltenberger, W; Walzel, G; Widl, E; Wulz, C-E; Mossolov, V; Shumeiko, N; Suarez Gonzalez, J; Benucci, L; Ceard, L; Cerny, K; De Wolf, E A; Janssen, X; Maes, T; Mucibello, L; Ochesanu, S; Roland, B; Rougny, R; Selvaggi, M; Van Haevermaet, H; Van Mechelen, P; Van Remortel, N; Adler, V; Beauceron, S; Blekman, F; Blyweert, S; D'Hondt, J; Devroede, O; Kalogeropoulos, A; Maes, J; Maes, M; Tavernier, S; Van Doninck, W; Van Mulders, P; Van Onsem, G P; Villella, I; Charaf, O; Clerbaux, B; De Lentdecker, G; Dero, V; Gay, A P R; Hammad, G H; Hreus, T; Marage, P E; Thomas, L; Vander Velde, C; Vanlaer, P; Wickens, J; Costantini, S; Grunewald, M; Klein, B; Marinov, A; Ryckbosch, D; Thyssen, F; Tytgat, M; Vanelderen, L; Verwilligen, P; Walsh, S; Zaganidis, N; Basegmez, S; Bruno, G; Caudron, J; De Favereau De Jeneret, J; Delaere, C; Demin, P; Favart, D; Giammanco, A; Grégoire, G; Hollar, J; Lemaitre, V; Liao, J; Militaru, O; Ovyn, S; Pagano, D; Pin, A; Piotrzkowski, K; Quertenmont, L; Schul, N; Beliy, N; Caebergs, T; Daubie, E; Alves, G A; De Jesus Damiao, D; Pol, M E; Souza, M H G; Carvalho, W; Da Costa, E M; De Oliveira Martins, C; Fonseca De Souza, S; Mundim, L; Nogima, H; Oguri, V; Prado Da Silva, W L; Santoro, A; Silva Do Amaral, S M; Sznajder, A; Torres Da Silva De Araujo, F; Dias, F A; Dias, M A F; Fernandez Perez, Tomei T R; Gregores, E M; Marinho, F; Novaes, S F; Padula, Sandra S; Darmenov, N; Dimitrov, L; Genchev, V; Iaydjiev, P; Piperov, S; Rodozov, M; Stoykova, S; Sultanov, G; Tcholakov, V; Trayanov, R; Vankov, I; Dyulendarova, M; Hadjiiska, R; Kozhuharov, V; Litov, L; Marinova, E; Mateev, M; Pavlov, B; Petkov, P; Bian, J G; Chen, G M; Chen, H S; Jiang, C H; Liang, D; Liang, S; Wang, J; Wang, J; Wang, X; Wang, Z; Xu, M; Yang, M; Zang, J; Zhang, Z; Ban, Y; Guo, S; Li, W; Mao, Y; Qian, S J; Teng, H; Zhu, B; Cabrera, A; Gomez Moreno, B; Ocampo Rios, A A; Osorio Oliveros, A F; Sanabria, J C; Godinovic, N; Lelas, D; Lelas, K; Plestina, R; Polic, D; Puljak, I; Antunovic, Z; Dzelalija, M; Brigljevic, V; Duric, S; Kadija, K; Morovic, S; Attikis, A; Fereos, R; Galanti, M; Mousa, J; Nicolaou, C; Ptochos, F; Razis, P A; Rykaczewski, H; Assran, Y; Mahmoud, M A; Hektor, A; Kadastik, M; Kannike, K; Müntel, M; Raidal, M; Rebane, L; Azzolini, V; Eerola, P; Czellar, S; Härkönen, J; Heikkinen, A; Karimäki, V; Kinnunen, R; Klem, J; Kortelainen, M J; Lampén, T; Lassila-Perini, K; Lehti, S; Lindén, T; Luukka, P; Mäenpää, T; Tuominen, E; Tuominiemi, J; Tuovinen, E; Ungaro, D; Wendland, L; Banzuzi, K; Korpela, A; Tuuva, T; Sillou, D; Besancon, M; Dejardin, M; Denegri, D; Fabbro, B; Faure, J L; Ferri, F; Ganjour, S; Gentit, F X; Givernaud, A; Gras, P; Hamel de Monchenault, G; Jarry, P; Locci, E; Malcles, J; Marionneau, M; Millischer, L; Rander, J; Rosowsky, A; Shreyber, I; Titov, M; Verrecchia, P; Baffioni, S; Beaudette, F; Bianchini, L; Bluj, M; Broutin, C; Busson, P; Charlot, C; Dobrzynski, L; Granier de Cassagnac, R; Haguenauer, M; Miné, P; Mironov, C; Ochando, C; Paganini, P; Porteboeuf, S; Sabes, D; Salerno, R; Sirois, Y; Thiebaux, C; Wyslouch, B; Zabi, A; Agram, J-L; Andrea, J; Besson, A; Bloch, D; Bodin, D; Brom, J-M; Cardaci, M; Chabert, E C; Collard, C; Conte, E; Drouhin, F; Ferro, C; Fontaine, J-C; Gelé, D; Goerlach, U; Greder, S; Juillot, P; Karim, M; Le Bihan, A-C; Mikami, Y; Van Hove, P; Fassi, F; Mercier, D; Baty, C; Beaupere, N; Bedjidian, M; Bondu, O; Boudoul, G; Boumediene, D; Brun, H; Chanon, N; Chierici, R; Contardo, D; Depasse, P; El Mamouni, H; Falkiewicz, A; Fay, J; Gascon, S; Ille, B; Kurca, T; Le Grand, T; Lethuillier, M; Mirabito, L; Perries, S; Sordini, V; Tosi, S; Tschudi, Y; Verdier, P; Xiao, H; Roinishvili, V; Anagnostou, G; Edelhoff, M; Feld, L; Heracleous, N; Hindrichs, O; Jussen, R; Klein, K; Merz, J; Mohr, N; Ostapchuk, A; Perieanu, A; Raupach, F; Sammet, J; Schael, S; Sprenger, D; Weber, H; Weber, M; Wittmer, B; Ata, M; Bender, W; Erdmann, M; Frangenheim, J; Hebbeker, T; Hinzmann, A; Hoepfner, K; Hof, C; Klimkovich, T; Klingebiel, D; Kreuzer, P; Lanske, D; Magass, C; Masetti, G; Merschmeyer, M; Meyer, A; Papacz, P; Pieta, H; Reithler, H; Schmitz, S A; Sonnenschein, L; Steggemann, J; Teyssier, D; Bontenackels, M; Davids, M; Duda, M; Flügge, G; Geenen, H; Giffels, M; Haj Ahmad, W; Heydhausen, D; Kress, T; Kuessel, Y; Linn, A; Nowack, A; Perchalla, L; Pooth, O; Rennefeld, J; Sauerland, P; Stahl, A; Thomas, M; Tornier, D; Zoeller, M H; Aldaya Martin, M; Behrenhoff, W; Behrens, U; Bergholz, M; Borras, K; Cakir, A; Campbell, A; Castro, E; Dammann, D; Eckerlin, G; Eckstein, D; Flossdorf, A; Flucke, G; Geiser, A; Glushkov, I; Hauk, J; Jung, H; Kasemann, M; Katkov, I; Katsas, P; Kleinwort, C; Kluge, H; Knutsson, A; Krücker, D; Kuznetsova, E; Lange, W; Lohmann, W; Mankel, R; Marienfeld, M; Melzer-Pellmann, I-A; Meyer, A B; Mnich, J; Mussgiller, A; Olzem, J; Parenti, A; Raspereza, A; Raval, A; Schmidt, R; Schoerner-Sadenius, T; Sen, N; Stein, M; Tomaszewska, J; Volyanskyy, D; Walsh, R; Wissing, C; Autermann, C; Bobrovskyi, S; Draeger, J; Enderle, H; Gebbert, U; Kaschube, K; Kaussen, G; Klanner, R; Mura, B; Naumann-Emme, S; Nowak, F; Pietsch, N; Sander, C; Schettler, H; Schleper, P; Schröder, M; Schum, T; Schwandt, J; Srivastava, A K; Stadie, H; Steinbrück, G; Thomsen, J; Wolf, R; Bauer, J; Buege, V; Chwalek, T; De Boer, W; Dierlamm, A; Dirkes, G; Feindt, M; Gruschke, J; Hackstein, C; Hartmann, F; Heindl, S M; Heinrich, M; Held, H; Hoffmann, K H; Honc, S; Kuhr, T; Martschei, D; Mueller, S; Müller, Th; Niegel, M; Oberst, O; Oehler, A; Ott, J; Peiffer, T; Piparo, D; Quast, G; Rabbertz, K; Ratnikov, F; Renz, M; Saout, C; Scheurer, A; Schieferdecker, P; Schilling, F-P; Schott, G; Simonis, H J; Stober, F M; Troendle, D; Wagner-Kuhr, J; Zeise, M; Zhukov, V; Ziebarth, E B; Daskalakis, G; Geralis, T; Kesisoglou, S; Kyriakis, A; Loukas, D; Manolakos, I; Markou, A; Markou, C; Mavrommatis, C; Petrakou, E; Gouskos, L; Mertzimekis, T J; Panagiotou, A; Evangelou, I; Foudas, C; Kokkas, P; Manthos, N; Papadopoulos, I; Patras, V; Triantis, F A; Aranyi, A; Bencze, G; Boldizsar, L; Debreczeni, G; Hajdu, C; Horvath, D; Kapusi, A; Krajczar, K; Laszlo, A; Sikler, F; Vesztergombi, G; Beni, N; Molnar, J; Palinkas, J; Szillasi, Z; Veszpremi, V; Raics, P; Trocsanyi, Z L; Ujvari, B; Bansal, S; Beri, S B; Bhatnagar, V; Dhingra, N; Jindal, M; Kaur, M; Kohli, J M; Mehta, M Z; Nishu, N; Saini, L K; Sharma, A; Singh, A P; Singh, J B; Singh, S P; Ahuja, S; Bhattacharya, S; Choudhary, B C; Gupta, P; Jain, S; Jain, S; Kumar, A; Shivpuri, R K; Choudhury, R K; Dutta, D; Kailas, S; Kataria, S K; Mohanty, A K; Pant, L M; Shukla, P; Suggisetti, P; Aziz, T; Guchait, M; Gurtu, A; Maity, M; Majumder, D; Majumder, G; Mazumdar, K; Mohanty, G B; Saha, A; Sudhakar, K; Wickramage, N; Banerjee, S; Dugad, S; Mondal, N K; Arfaei, H; Bakhshiansohi, H; Etesami, S M; Fahim, A; Hashemi, M; Jafari, A; Khakzad, M; Mohammadi, A; Mohammadi Najafabadi, M; Paktinat Mehdiabadi, S; Safarzadeh, B; Zeinali, M; Abbrescia, M; Barbone, L; Calabria, C; Colaleo, A; Creanza, D; De Filippis, N; De Palma, M; Dimitrov, A; Fiore, L; Iaselli, G; Lusito, L; Maggi, G; Maggi, M; Manna, N; Marangelli, B; My, S; Nuzzo, S; Pacifico, N; Pierro, G A; Pompili, A; Pugliese, G; Romano, F; Roselli, G; Selvaggi, G; Silvestris, L; Trentadue, R; Tupputi, S; Zito, G; Abbiendi, G; Benvenuti, A C; Bonacorsi, D; Braibant-Giacomelli, S; Capiluppi, P; Castro, A; Cavallo, F R; Cuffiani, M; Dallavalle, G M; Fabbri, F; Fanfani, A; Fasanella, D; Giacomelli, P; Giunta, M; Grandi, C; Marcellini, S; Meneghelli, M; Montanari, A; Navarria, F L; Odorici, F; Perrotta, A; Rossi, A M; Rovelli, T; Siroli, G; Travaglini, R; Albergo, S; Cappello, G; Chiorboli, M; Costa, S; Tricomi, A; Tuve, C; Barbagli, G; Ciulli, V; Civinini, C; D'Alessandro, R; Focardi, E; Frosali, S; Gallo, E; Genta, C; Lenzi, P; Meschini, M; Paoletti, S; Sguazzoni, G; Tropiano, A; Benussi, L; Bianco, S; Colafranceschi, S; Fabbri, F; Piccolo, D; Fabbricatore, P; Musenich, R; Benaglia, A; Cerati, G B; De Guio, F; Di Matteo, L; Ghezzi, A; Malberti, M; Malvezzi, S; Martelli, A; Massironi, A; Menasce, D; Moroni, L; Paganoni, M; Pedrini, D; Ragazzi, S; Redaelli, N; Sala, S; Tabarelli de Fatis, T; Tancini, V; Buontempo, S; Carrillo Montoya, C A; Cimmino, A; De Cosa, A; De Gruttola, M; Fabozzi, F; Iorio, A O M; Lista, L; Merola, M; Noli, P; Paolucci, P; Azzi, P; Bacchetta, N; Bellan, P; Bellato, M; Bisello, D; Branca, A; Checchia, P; Conti, E; De Mattia, M; Dorigo, T; Gasparini, F; Giubilato, P; Gresele, A; Lacaprara, S; Lazzizzera, I; Margoni, M; Maron, G; Meneguzzo, A T; Nespolo, M; Passaseo, M; Perrozzi, L; Pozzobon, N; Ronchese, P; Simonetto, F; Torassa, E; Tosi, M; Triossi, A; Vanini, S; Zotto, P; Zumerle, G; Baesso, P; Berzano, U; Riccardi, C; Torre, P; Vitulo, P; Viviani, C; Biasini, M; Bilei, G M; Caponeri, B; Fanò, L; Lariccia, P; Lucaroni, A; Mantovani, G; Menichelli, M; Nappi, A; Santocchia, A; Servoli, L; Taroni, S; Valdata, M; Volpe, R; Azzurri, P; Bagliesi, G; Bernardini, J; Boccali, T; Broccolo, G; Castaldi, R; D'Agnolo, R T; Dell'Orso, R; Fiori, F; Foà, L; Giassi, A; Kraan, A; Ligabue, F; Lomtadze, T; Martini, L; Messineo, A; Palla, F; Palmonari, F; Sarkar, S; Segneri, G; Serban, A T; Spagnolo, P; Tenchini, R; Tonelli, G; Venturi, A; Verdini, P G; Barone, L; Cavallari, F; Del Re, D; Di Marco, E; Diemoz, M; Franci, D; Grassi, M; Longo, E; Organtini, G; Palma, A; Pandolfi, F; Paramatti, R; Rahatlou, S; Amapane, N; Arcidiacono, R; Argiro, S; Arneodo, M; Biino, C; Botta, C; Cartiglia, N; Castello, R; Costa, M; Demaria, N; Graziano, A; Mariotti, C; Marone, M; Maselli, S; Migliore, E; Mila, G; Monaco, V; Musich, M; Obertino, M M; Pastrone, N; Pelliccioni, M; Romero, A; Ruspa, M; Sacchi, R; Sola, V; Solano, A; Staiano, A; Trocino, D; Vilela Pereira, A; Ambroglini, F; Belforte, S; Cossutti, F; Della Ricca, G; Gobbo, B; Montanino, D; Penzo, A; Heo, S G; Chang, S; Chung, J; Kim, D H; Kim, G N; Kim, J E; Kong, D J; Park, H; Son, D; Son, D C; Kim, Zero; Kim, J Y; Song, S; Choi, S; Hong, B; Jo, M; Kim, H; Kim, J H; Kim, T J; Lee, K S; Moon, D H; Park, S K; Rhee, H B; Seo, E; Shin, S; Sim, K S; Choi, M; Kang, S; Kim, H; Park, C; Park, I C; Park, S; Ryu, G; Choi, Y; Choi, Y K; Goh, J; Lee, J; Lee, S; Seo, H; Yu, I; Bilinskas, M J; Grigelionis, I; Janulis, M; Martisiute, D; Petrov, P; Sabonis, T; Castilla Valdez, H; De La Cruz Burelo, E; Lopez-Fernandez, R; Sánchez Hernández, A; Villasenor-Cendejas, L M; Carrillo Moreno, S; Vazquez Valencia, F; Salazar Ibarguen, H A; Casimiro Linares, E; Morelos Pineda, A; Reyes-Santos, M A; Allfrey, P; Krofcheck, D; Tam, J; Butler, P H; Doesburg, R; Silverwood, H; Ahmad, M; Ahmed, I; Asghar, M I; Hoorani, H R; Khan, W A; Khurshid, T; Qazi, S; Cwiok, M; Dominik, W; Doroba, K; Kalinowski, A; Konecki, M; Krolikowski, J; Frueboes, T; Gokieli, R; Górski, M; Kazana, M; Nawrocki, K; Romanowska-Rybinska, K; Szleper, M; Wrochna, G; Zalewski, P; Almeida, N; David, A; Faccioli, P; Ferreira Parracho, P G; Gallinaro, M; Martins, P; Musella, P; Nayak, A; Ribeiro, P Q; Seixas, J; Silva, P; Varela, J; Wöhri, H K; Belotelov, I; Bunin, P; Finger, M; Finger, M; Golutvin, I; Kamenev, A; Karjavin, V; Kozlov, G; Lanev, A; Moisenz, P; Palichik, V; Perelygin, V; Shmatov, S; Smirnov, V; Volodko, A; Zarubin, A; Bondar, N; Golovtsov, V; Ivanov, Y; Kim, V; Levchenko, P; Murzin, V; Oreshkin, V; Smirnov, I; Sulimov, V; Uvarov, L; Vavilov, S; Vorobyev, A; Andreev, Yu; Gninenko, S; Golubev, N; Kirsanov, M; Krasnikov, N; Matveev, V; Pashenkov, A; Toropin, A; Troitsky, S; Epshteyn, V; Gavrilov, V; Kaftanov, V; Kossov, M; Krokhotin, A; Lychkovskaya, N; Safronov, G; Semenov, S; Stolin, V; Vlasov, E; Zhokin, A; Boos, E; Dubinin, M; Dudko, L; Ershov, A; Gribushin, A; Kodolova, O; Lokhtin, I; Obraztsov, S; Petrushanko, S; Sarycheva, L; Savrin, V; Snigirev, A; Andreev, V; Azarkin, M; Dremin, I; Kirakosyan, M; Rusakov, S V; Vinogradov, A; Azhgirey, I; Bitioukov, S; Grishin, V; Kachanov, V; Konstantinov, D; Korablev, A; Krychkine, V; Petrov, V; Ryutin, R; Slabospitsky, S; Sobol, A; Tourtchanovitch, L; Troshin, S; Tyurin, N; Uzunian, A; Volkov, A; Adzic, P; Djordjevic, M; Krpic, D; Milosevic, J; Aguilar-Benitez, M; Alcaraz Maestre, J; Arce, P; Battilana, C; Calvo, E; Cepeda, M; Cerrada, M; Colino, N; De La Cruz, B; Diez Pardos, C; Fernandez Bedoya, C; Fernández Ramos, J P; Ferrando, A; Flix, J; Fouz, M C; Garcia-Abia, P; Gonzalez Lopez, O; Goy Lopez, S; Hernandez, J M; Josa, M I; Merino, G; Puerta Pelayo, J; Redondo, I; Romero, L; Santaolalla, J; Willmott, C; Albajar, C; Codispoti, G; de Trocóniz, J F; Cuevas, J; Fernandez Menendez, J; Folgueras, S; Gonzalez Caballero, I; Lloret Iglesias, L; Vizan Garcia, J M; Brochero Cifuentes, J A; Cabrillo, I J; Calderon, A; Chamizo Llatas, M; Chuang, S H; Duarte Campderros, J; Felcini, M; Fernandez, M; Gomez, G; Gonzalez Sanchez, J; Gonzalez Suarez, R; Jorda, C; Lobelle Pardo, P; Lopez Virto, A; Marco, J; Marco, R; Martinez Rivero, C; Matorras, F; Munoz Sanchez, F J; Piedra Gomez, J; Rodrigo, T; Ruiz Jimeno, A; Scodellaro, L; Sobron Sanudo, M; Vila, I; Vilar Cortabitarte, R; Abbaneo, D; Auffray, E; Auzinger, G; Baillon, P; Ball, A H; Barney, D; Bell, A J; Benedetti, D; Bernet, C; Bialas, W; Bloch, P; Bocci, A; Bolognesi, S; Breuker, H; Brona, G; Bunkowski, K; Camporesi, T; Cano, E; Cerminara, G; Christiansen, T; Coarasa Perez, J A; Covarelli, R; Curé, B; D'Enterria, D; Dahms, T; De Roeck, A; Duarte Ramos, F; Elliott-Peisert, A; Funk, W; Gaddi, A; Gennai, S; Georgiou, G; Gerwig, H; Gigi, D; Gill, K; Giordano, D; Glege, F; Gomez-Reino Garrido, R; Gouzevitch, M; Govoni, P; Gowdy, S; Guiducci, L; Hansen, M; Harvey, J; Hegeman, J; Hegner, B; Henderson, C; Hoffmann, H F; Honma, A; Innocente, V; Janot, P; Karavakis, E; Lecoq, P; Leonidopoulos, C; Lourenço, C; Macpherson, A; Mäki, T; Malgeri, L; Mannelli, M; Masetti, L; Meijers, F; Mersi, S; Meschi, E; Moser, R; Mozer, M U; Mulders, M; Nesvold, E; Nguyen, M; Orimoto, T; Orsini, L; Perez, E; Petrilli, A; Pfeiffer, A; Pierini, M; Pimiä, M; Polese, G; Racz, A; Rolandi, G; Rommerskirchen, T; Rovelli, C; Rovere, M; Sakulin, H; Schäfer, C; Schwick, C; Segoni, I; Sharma, A; Siegrist, P; Simon, M; Sphicas, P; Spiga, D; Spiropulu, M; Stöckli, F; Stoye, M; Tropea, P; Tsirou, A; Tsyganov, A; Veres, G I; Vichoudis, P; Voutilainen, M; Zeuner, W D; Bertl, W; Deiters, K; Erdmann, W; Gabathuler, K; Horisberger, R; Ingram, Q; Kaestli, H C; König, S; Kotlinski, D; Langenegger, U; Meier, F; Renker, D; Rohe, T; Sibille, J; Starodumov, A; Bortignon, P; Caminada, L; Chen, Z; Cittolin, S; Dissertori, G; Dittmar, M; Eugster, J; Freudenreich, K; Grab, C; Hervé, A; Hintz, W; Lecomte, P; Lustermann, W; Marchica, C; Martinez Ruiz del Arbol, P; Meridiani, P; Milenovic, P; Moortgat, F; Nef, P; Nessi-Tedaldi, F; Pape, L; Pauss, F; Punz, T; Rizzi, A; Ronga, F J; Sala, L; Sanchez, A K; Sawley, M-C; Stieger, B; Tauscher, L; Thea, A; Theofilatos, K; Treille, D; Urscheler, C; Wallny, R; Weber, M; Wehrli, L; Weng, J; Aguiló, E; Amsler, C; Chiochia, V; De Visscher, S; Favaro, C; Ivova Rikova, M; Millan Mejias, B; Regenfus, C; Robmann, P; Schmidt, A; Snoek, H; Wilke, L; Chang, Y H; Chen, K H; Chen, W T; Dutta, S; Go, A; Kuo, C M; Li, S W; Lin, W; Liu, M H; Liu, Z K; Lu, Y J; Wu, J H; Yu, S S; Bartalini, P; Chang, P; Chang, Y H; Chang, Y W; Chao, Y; Chen, K F; Hou, W-S; Hsiung, Y; Kao, K Y; Lei, Y J; Lu, R-S; Shiu, J G; Tzeng, Y M; Wang, M; Adiguzel, A; Bakirci, M N; Cerci, S; Dozen, C; Dumanoglu, I; Eskut, E; Girgis, S; Gokbulut, G; Guler, Y; Gurpinar, E; Hos, I; Kangal, E E; Karaman, T; Kayis Topaksu, A; Nart, A; Onengut, G; Ozdemir, K; Ozturk, S; Polatoz, A; Sogut, K; Tali, B; Topakli, H; Uzun, D; Vergili, L N; Vergili, M; Zorbilmez, C; Akin, I V; Aliev, T; Bilmis, S; Deniz, M; Gamsizkan, H; Guler, A M; Ocalan, K; Ozpineci, A; Serin, M; Sever, R; Surat, U E; Yildirim, E; Zeyrek, M; Deliomeroglu, M; Demir, D; Gülmez, E; Halu, A; Isildak, B; Kaya, M; Kaya, O; Ozbek, M; Ozkorucuklu, S; Sonmez, N; Levchuk, L; Bell, P; Bostock, F; Brooke, J J; Cheng, T L; Clement, E; Cussans, D; Frazier, R; Goldstein, J; Grimes, M; Hansen, M; Hartley, D; Heath, G P; Heath, H F; Huckvale, B; Jackson, J; Kreczko, L; Metson, S; Newbold, D M; Nirunpong, K; Poll, A; Senkin, S; Smith, V J; Ward, S; Basso, L; Bell, K W; Belyaev, A; Brew, C; Brown, R M; Camanzi, B; Cockerill, D J A; Coughlan, J A; Harder, K; Harper, S; Kennedy, B W; Olaiya, E; Petyt, D; Radburn-Smith, B C; Shepherd-Themistocleous, C H; Tomalin, I R; Womersley, W J; Worm, S D; Bainbridge, R; Ball, G; Ballin, J; Beuselinck, R; Buchmuller, O; Colling, D; Cripps, N; Cutajar, M; Davies, G; Della Negra, M; Fulcher, J; Futyan, D; Guneratne Bryer, A; Hall, G; Hatherell, Z; Hays, J; Iles, G; Karapostoli, G; Lyons, L; Magnan, A-M; Marrouche, J; Nandi, R; Nash, J; Nikitenko, A; Papageorgiou, A; Pesaresi, M; Petridis, K; Pioppi, M; Raymond, D M; Rompotis, N; Rose, A; Ryan, M J; Seez, C; Sharp, P; Sparrow, A; Tapper, A; Tourneur, S; Vazquez Acosta, M; Virdee, T; Wakefield, S; Wardrope, D; Whyntie, T; Barrett, M; Chadwick, M; Cole, J E; Hobson, P R; Khan, A; Kyberd, P; Leslie, D; Martin, W; Reid, I D; Teodorescu, L; Hatakeyama, K; Bose, T; Carrera Jarrin, E; Clough, A; Fantasia, C; Heister, A; St John, J; Lawson, P; Lazic, D; Rohlf, J; Sperka, D; Sulak, L; Avetisyan, A; Bhattacharya, S; Chou, J P; Cutts, D; Esen, S; Ferapontov, A; Heintz, U; Jabeen, S; Kukartsev, G; Landsberg, G; Narain, M; Nguyen, D; Segala, M; Speer, T; Tsang, K V; Borgia, M A; Breedon, R; Calderon De La Barca Sanchez, M; Cebra, D; Chauhan, S; Chertok, M; Conway, J; Cox, P T; Dolen, J; Erbacher, R; Friis, E; Ko, W; Kopecky, A; Lander, R; Liu, H; Maruyama, S; Miceli, T; Nikolic, M; Pellett, D; Robles, J; Schwarz, T; Searle, M; Smith, J; Squires, M; Tripathi, M; Vasquez Sierra, R; Veelken, C; Andreev, V; Arisaka, K; Cline, D; Cousins, R; Deisher, A; Duris, J; Erhan, S; Farrell, C; Hauser, J; Ignatenko, M; Jarvis, C; Plager, C; Rakness, G; Schlein, P; Tucker, J; Valuev, V; Babb, J; Clare, R; Ellison, J; Gary, J W; Giordano, F; Hanson, G; Jeng, G Y; Kao, S C; Liu, F; Liu, H; Luthra, A; Nguyen, H; Pasztor, G; Satpathy, A; Shen, B C; Stringer, R; Sturdy, J; Sumowidagdo, S; Wilken, R; Wimpenny, S; Andrews, W; Branson, J G; Dusinberre, E; Evans, D; Golf, F; Holzner, A; Kelley, R; Lebourgeois, M; Letts, J; Mangano, B; Muelmenstaedt, J; Padhi, S; Palmer, C; Petrucciani, G; Pi, H; Pieri, M; Ranieri, R; Sani, M; Sharma, V; Simon, S; Tu, Y; Vartak, A; Würthwein, F; Yagil, A; Barge, D; Bellan, R; Campagnari, C; D'Alfonso, M; Danielson, T; Geffert, P; Incandela, J; Justus, C; Kalavase, P; Koay, S A; Kovalskyi, D; Krutelyov, V; Lowette, S; McColl, N; Pavlunin, V; Rebassoo, F; Ribnik, J; Richman, J; Rossin, R; Stuart, D; To, W; Vlimant, J R; Bornheim, A; Bunn, J; Chen, Y; Gataullin, M; Kcira, D; Litvine, V; Ma, Y; Mott, A; Newman, H B; Rogan, C; Timciuc, V; Traczyk, P; Veverka, J; Wilkinson, R; Yang, Y; Zhu, R Y; Akgun, B; Carroll, R; Ferguson, T; Iiyama, Y; Jang, D W; Jun, S Y; Liu, Y F; Paulini, M; Russ, J; Terentyev, N; Vogel, H; Vorobiev, I; Cumalat, J P; Dinardo, M E; Drell, B R; Edelmaier, C J; Ford, W T; Heyburn, B; Luiggi Lopez, E; Nauenberg, U; Smith, J G; Stenson, K; Ulmer, K A; Wagner, S R; Zang, S L; Agostino, L; Alexander, J; Chatterjee, A; Das, S; Eggert, N; Fields, L J; Gibbons, L K; Heltsley, B; Hopkins, W; Khukhunaishvili, A; Kreis, B; Kuznetsov, V; Nicolas Kaufman, G; Patterson, J R; Puigh, D; Riley, D; Ryd, A; Shi, X; Sun, W; Teo, W D; Thom, J; Thompson, J; Vaughan, J; Weng, Y; Winstrom, L; Wittich, P; Biselli, A; Cirino, G; Winn, D; Abdullin, S; Albrow, M; Anderson, J; Apollinari, G; Atac, M; Bakken, J A; Banerjee, S; Bauerdick, L A T; Beretvas, A; Berryhill, J; Bhat, P C; Bloch, I; Borcherding, F; Burkett, K; Butler, J N; Chetluru, V; Cheung, H W K; Chlebana, F; Cihangir, S; Demarteau, M; Eartly, D P; Elvira, V D; Fisk, I; Freeman, J; Gao, Y; Gottschalk, E; Green, D; Gunthoti, K; Gutsche, O; Hahn, A; Hanlon, J; Harris, R M; Hirschauer, J; Hooberman, B; James, E; Jensen, H; Johnson, M; Joshi, U; Khatiwada, R; Kilminster, B; Klima, B; Kousouris, K; Kunori, S; Kwan, S; Limon, P; Lipton, R; Lykken, J; Maeshima, K; Marraffino, J M; Mason, D; McBride, P; McCauley, T; Miao, T; Mishra, K; Mrenna, S; Musienko, Y; Newman-Holmes, C; O'Dell, V; Popescu, S; Pordes, R; Prokofyev, O; Saoulidou, N; Sexton-Kennedy, E; Sharma, S; Soha, A; Spalding, W J; Spiegel, L; Tan, P; Taylor, L; Tkaczyk, S; Uplegger, L; Vaandering, E W; Vidal, R; Whitmore, J; Wu, W; Yang, F; Yumiceva, F; Yun, J C; Acosta, D; Avery, P; Bourilkov, D; Chen, M; Di Giovanni, G P; Dobur, D; Drozdetskiy, A; Field, R D; Fisher, M; Fu, Y; Furic, I K; Gartner, J; Goldberg, S; Kim, B; Klimenko, S; Konigsberg, J; Korytov, A; Kropivnitskaya, A; Kypreos, T; Matchev, K; Mitselmakher, G; Muniz, L; Pakhotin, Y; Prescott, C; Remington, R; Schmitt, M; Scurlock, B; Sellers, P; Skhirtladze, N; Wang, D; Yelton, J; Zakaria, M; Ceron, C; Gaultney, V; Kramer, L; Lebolo, L M; Linn, S; Markowitz, P; Martinez, G; Rodriguez, J L; Adams, T; Askew, A; Bandurin, D; Bochenek, J; Chen, J; Diamond, B; Gleyzer, S V; Haas, J; Hagopian, S; Hagopian, V; Jenkins, M; Johnson, K F; Prosper, H; Sekmen, S; Veeraraghavan, V; Baarmand, M M; Dorney, B; Guragain, S; Hohlmann, M; Kalakhety, H; Ralich, R; Vodopiyanov, I; Adams, M R; Anghel, I M; Apanasevich, L; Bai, Y; Bazterra, V E; Betts, R R; Callner, J; Cavanaugh, R; Dragoiu, C; Garcia-Solis, E J; Gerber, C E; Hofman, D J; Khalatyan, S; Lacroix, F; O'Brien, C; Silvestre, C; Smoron, A; Strom, D; Varelas, N; Akgun, U; Albayrak, E A; Bilki, B; Cankocak, K; Clarida, W; Duru, F; Lae, C K; McCliment, E; Merlo, J-P; Mermerkaya, H; Mestvirishvili, A; Moeller, A; Nachtman, J; Newsom, C R; Norbeck, E; Olson, J; Onel, Y; Ozok, F; Sen, S; Wetzel, J; Yetkin, T; Yi, K; Barnett, B A; Blumenfeld, B; Bonato, A; Eskew, C; Fehling, D; Giurgiu, G; Gritsan, A V; Guo, Z J; Hu, G; Maksimovic, P; Rappoccio, S; Swartz, M; Tran, N V; Whitbeck, A; Baringer, P; Bean, A; Benelli, G; Grachov, O; Murray, M; Noonan, D; Radicci, V; Sanders, S; Wood, J S; Zhukova, V; Bolton, T; Chakaberia, I; Ivanov, A; Makouski, M; Maravin, Y; Shrestha, S; Svintradze, I; Wan, Z; Gronberg, J; Lange, D; Wright, D; Baden, A; Boutemeur, M; Eno, S C; Ferencek, D; Gomez, J A; Hadley, N J; Kellogg, R G; Kirn, M; Lu, Y; Mignerey, A C; Rossato, K; Rumerio, P; Santanastasio, F; Skuja, A; Temple, J; Tonjes, M B; Tonwar, S C; Twedt, E; Alver, B; Bauer, G; Bendavid, J; Busza, W; Butz, E; Cali, I A; Chan, M; Dutta, V; Everaerts, P; Gomez Ceballos, G; Goncharov, M; Hahn, K A; Harris, P; Kim, Y; Klute, M; Lee, Y-J; Li, W; Loizides, C; Luckey, P D; Ma, T; Nahn, S; Paus, C; Roland, C; Roland, G; Rudolph, M; Stephans, G S F; Sumorok, K; Sung, K; Wenger, E A; Xie, S; Yang, M; Yilmaz, Y; Yoon, A S; Zanetti, M; Cole, P; Cooper, S I; Cushman, P; Dahmes, B; De Benedetti, A; Dudero, P R; Franzoni, G; Haupt, J; Klapoetke, K; Kubota, Y; Mans, J; Rekovic, V; Rusack, R; Sasseville, M; Singovsky, A; Cremaldi, L M; Godang, R; Kroeger, R; Perera, L; Rahmat, R; Sanders, D A; Summers, D; Bloom, K; Bose, S; Butt, J; Claes, D R; Dominguez, A; Eads, M; Keller, J; Kelly, T; Kravchenko, I; Lazo-Flores, J; Lundstedt, C; Malbouisson, H; Malik, S; Snow, G R; Baur, U; Godshalk, A; Iashvili, I; Kharchilava, A; Kumar, A; Shipkowski, S P; Smith, K; Alverson, G; Barberis, E; Baumgartel, D; Boeriu, O; Chasco, M; Kaadze, K; Reucroft, S; Swain, J; Wood, D; Zhang, J; Anastassov, A; Kubik, A; Odell, N; Ofierzynski, R A; Pollack, B; Pozdnyakov, A; Schmitt, M; Stoynev, S; Velasco, M; Won, S; Antonelli, L; Berry, D; Hildreth, M; Jessop, C; Karmgard, D J; Kolb, J; Kolberg, T; Lannon, K; Luo, W; Lynch, S; Marinelli, N; Morse, D M; Pearson, T; Ruchti, R; Slaunwhite, J; Valls, N; Warchol, J; Wayne, M; Ziegler, J; Bylsma, B; Durkin, L S; Gu, J; Hill, C; Killewald, P; Kotov, K; Ling, T Y; Rodenburg, M; Williams, G; Adam, N; Berry, E; Elmer, P; Gerbaudo, D; Halyo, V; Hebda, P; Hunt, A; Jones, J; Laird, E; Lopes Pegna, D; Marlow, D; Medvedeva, T; Mooney, M; Olsen, J; Piroué, P; Quan, X; Saka, H; Stickland, D; Tully, C; Werner, J S; Zuranski, A; Acosta, J G; Huang, X T; Lopez, A; Mendez, H; Oliveros, S; Ramirez Vargas, J E; Zatserklyaniy, A; Alagoz, E; Barnes, V E; Bolla, G; Borrello, L; Bortoletto, D; Everett, A; Garfinkel, A F; Gecse, Z; Gutay, L; Hu, Z; Jones, M; Koybasi, O; Laasanen, A T; Leonardo, N; Liu, C; Maroussov, V; Merkel, P; Miller, D H; Neumeister, N; Potamianos, K; Shipsey, I; Silvers, D; Svyatkovskiy, A; Yoo, H D; Zablocki, J; Zheng, Y; Jindal, P; Parashar, N; Boulahouache, C; Cuplov, V; Ecklund, K M; Geurts, F J M; Liu, J H; Morales, J; Padley, B P; Redjimi, R; Roberts, J; Zabel, J; Betchart, B; Bodek, A; Chung, Y S; de Barbaro, P; Demina, R; Eshaq, Y; Flacher, H; Garcia-Bellido, A; Goldenzweig, P; Gotra, Y; Han, J; Harel, A; Miner, D C; Orbaker, D; Petrillo, G; Vishnevskiy, D; Zielinski, M; Bhatti, A; Demortier, L; Goulianos, K; Lungu, G; Mesropian, C; Yan, M; Atramentov, O; Barker, A; Duggan, D; Gershtein, Y; Gray, R; Halkiadakis, E; Hidas, D; Hits, D; Lath, A; Panwalkar, S; Patel, R; Richards, A; Rose, K; Schnetzer, S; Somalwar, S; Stone, R; Thomas, S; Cerizza, G; Hollingsworth, M; Spanier, S; Yang, Z C; York, A; Asaadi, J; Eusebi, R; Gilmore, J; Gurrola, A; Kamon, T; Khotilovich, V; Montalvo, R; Nguyen, C N; Pivarski, J; Safonov, A; Sengupta, S; Tatarinov, A; Toback, D; Weinberger, M; Akchurin, N; Bardak, C; Damgov, J; Jeong, C; Kovitanggoon, K; Lee, S W; Mane, P; Roh, Y; Sill, A; Volobouev, I; Wigmans, R; Yazgan, E; Appelt, E; Brownson, E; Engh, D; Florez, C; Gabella, W; Johns, W; Kurt, P; Maguire, C; Melo, A; Sheldon, P; Velkovska, J; Arenton, M W; Balazs, M; Boutle, S; Buehler, M; Conetti, S; Cox, B; Francis, B; Hirosky, R; Ledovskoy, A; Lin, C; Neu, C; Yohay, R; Gollapinni, S; Harr, R; Karchin, P E; Mattson, M; Milstène, C; Sakharov, A; Anderson, M; Bachtis, M; Bellinger, J N; Carlsmith, D; Dasu, S; Efron, J; Gray, L; Grogg, K S; Grothe, M; Hall-Wilton, R; Herndon, M; Klabbers, P; Klukas, J; Lanaro, A; Lazaridis, C; Leonard, J; Lomidze, D; Loveless, R; Mohapatra, A; Parker, W; Reeder, D; Ross, I; Savin, A; Smith, W H; Swanson, J; Weinberg, M
2011-01-07
The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1×10(32) cm-2 s-1, an integrated luminosity of 10 pb-1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino lifetime are set. For a mass difference mg - mχ1(0) >100 GeV/c2, and assuming BR(g→gχ1(0))=100%, mg < 370 GeV/c2 are excluded for lifetimes from 10 μs to 1000 s.
Wang, Wenjuan; Peng, Xuan; Cao, Dapeng
2011-06-01
Adsorption of H(2)S and SO(2) pure gases and their selective capture from the H(2)S-CH(4), H(2)S-CO(2), SO(2)-N(2), and SO(2)-CO(2) binary mixtures by the single-walled carbon nanotubes (SWNT) are investigated via using the grand canonical Monte Carlo (GCMC) method. It is found that the (20, 20) SWNT with larger diameter shows larger capacity for H(2)S and SO(2) pure gases at T = 303 K, in which the uptakes reach 16.31 and 16.03 mmol/g, respectively. However, the (6,6) SWNT with small diameter exhibits the largest selectivity for binary mixtures containing trace sulfur gases at T = 303 K and P = 100 kPa. By investigating the effect of pore size on the separation of gas mixtures, we found that the optimized pore size is 0.81 nm for separation of H(2)S-CH(4), H(2)S-CO(2), and SO(2)-N(2) binary mixtures, while it is 1.09 nm for the SO(2)-CO(2) mixture. The effects of concentration and temperature on the selectivity of sulfide are also studied at the optimal pore size. It is found that the concentration (ppm) of sulfur components has little effect on selectivity of SWNTs for these binary mixtures. However, the selectivity decreases obviously with the increase of temperature. To improve the adsorption capacities, we further modify the surface of SWNTs with the functional groups. The selectivities of H(2)S-CO(2) and SO(2)-CO(2) mixtures are basically uninfluenced by the site density, while the increase of site density can improve the selectivity of H(2)S-CH(4) mixture doubly. It is expected that this work could provide useful information for sulfur gas capture.
NASA Astrophysics Data System (ADS)
Roses, Timothy P.; Lee Davisson, M.; Criss, Robert E.
1996-05-01
The more than 1550 km2 (600 mi2) Hat Creek Basin in northeastern California is host to several first magnitude cold springs that emanate from Quaternary basaltic rocks with individual discharge rates ranging from 1.7 to 8.5 m3 s-1 (60-300 ft3 s-1). Stable isotope (δ18O, δD, δ13C) and 14C measurements of surface and groundwater samples were used to identify recharge areas, and to evaluate aquifer residence times and flow paths. Recharge locations were constrained from the regional decrement in meteoric water δ18O values as a function of elevation, determined to be -0.23‰ per 100 m for small springs and creek waters collected along the western Cascade slope of this region. In general, the large-volume springs are lower in (δ18O than surrounding meteoric waters, and are inferred to originate in high-elevation, high-precipitation regions up to 50 km away from their discharge points. Large spring 14C abundances range from 99 to 41 % modern carbon (pmc), and most show evidence of interaction with three distinct carbon isotope reservoirs. These reservoirs are tentatively identified as (1) soil CO2 gas equilibrated under open system conditions with groundwater in the recharge zone [δ13CDIC ≈ -18‰, 14C > 100 pmc], (2) dissolved carbon equilibrated with atmospheric CO2 gas [δ13CDIC ≈ +1‰, 14C > 100 pmc], and (3) dissolved carbon derived from volcanic CO2 gas emissions [δ13CDIC≈0‰, 14C=0 pmc]. Many regional waters show a decrease in 14C abundance with increasing δ13C values, a pattern indicative of interaction with dead carbon originating from volcanic CO2 gas. Several lines of evidence suggest that actual groundwater residence times are too short (⩽ 200 years) to apply radiocarbon dating corrections. In particular, water temperatures measured at springs show that deep groundwater circulation does not occur, which implies an insufficient aquifer volume to account for both the high discharge rates and long residence times suggested by 14C apparent ages. The large springs also exhibit rapid decreases in flow during periods of drought that suggests a high level of aquifer interconnectivity to the recharge area. The estimated amount of volcanic CO2 dissolved in surface and groundwater originating from the Lassen highlands is consistent with the conversion of approximately 10% of the geothermal CO2 flux into dissolved inorganic carbon.
Asm-Triggered too Observations of 100,000 C/s Black Hole Candidates
NASA Astrophysics Data System (ADS)
van der Klis, Michiel
Resubmission accepted Cycle 2&3 proposal. - The PCA is unique by the high count rates (~100,000 c/s) it can record, and its resulting extreme sensitivity to weak variability. Only few sources get this bright. Our Cycle 1-3 work on Sco X-1 and 1744-28 shows that high count rate observations are very rewarding, but also difficult and not without risk. In the life of the satellite probably only one black-hole transient (if any) will reach 100,000 c/s levels. When this occurs, a window of discovery will be opened on black holes, which will nearly certainly close again within a few days. This proposal aims at ensuring that optimal use is made of this opportunity by performing state-of- the-art high count rate observations covering all of the most crucial aspects of the source variability.
Asm-Triggered too Observations of 100,000 C/s Black Hole Candidates
NASA Astrophysics Data System (ADS)
van der Klis, Michiel
Resubmission accepted Cycle 2,3&4 proposal. - The PCA is unique by the high count rates (~100,000 c/s) it can record, and its resulting extreme sensitivity to weak variability. Only few sources get this bright. Our Cycle 1-3 work on Sco X-1 and 1744-28 shows that high count rate observations are very rewarding, but also difficult and not without risk. In the life of the satellite probably only one black-hole transient (if any) will reach 100,000 c/s levels. When this occurs, a window of discovery will be opened on black holes, which will nearly certainly close again within a few days. This proposal aims at ensuring that optimal use is made of this opportunity by performing state-of- the-art high count rate observations covering all of the most crucial aspects of the source variability.
Study of the liquid vapor equilibrium in the bromine-hydrobromic acid-water system
NASA Technical Reports Server (NTRS)
Benizri, R.; Lessart, P.; Courvoisier, P.
1984-01-01
A glass ebullioscope was built and at atmospheric pressure, liquid-vapor equilibria relative to the Br2-HBr-H2O system, in the concentration range of interest for evaluation of the Mark 13 cycle was studied. Measurements were performed for the brome-azeotrope (HBr-H2O) pseudo-binary system and for the ternary system at temperatures lower than 125 C and in the bromine concentration range up to 13% wt.
First Spectroscopic Studies and Detection in SgrB2 of 13C-DOUBLY Substitued Ethyl Cyanide
NASA Astrophysics Data System (ADS)
Margulès, L.; Motiyenko, R. A.; Guillemin, J.-C.; Müller, Holger S. P.; Belloche, Arnaud
2015-06-01
Ethyl cyanide (CH_3CH_2CN) is one of the most abundant complex organic molecules in the interstellar medium firstly detected in OMC-1 and Sgr B2 in 1977. The vibrationally excited states are enough populated under ISM conditions and could be detected. Apart from the deuterated ones, all mono-substituted isotopologues of ethyl cyanide (13C and 15N have been detected in the ISM. The detection of isotopologues in the ISM is important: it can give information about the formation process of complex organic molecules, and it is essential to clean the ISM spectra from the lines of known molecules in order to detect new ones. The 12C/13C ratio found in SgrB2: 20-30 suggests that the doubly 13C could be present in the spectral line survey recently obtained with ALMA (EMoCA), but no spectroscopic studies exist up to now. We measured and analyzed the spectra of the 13C-doubly-substitued species up to 1 THz with the Lille solid-state based spectrometer. The spectroscopic results and and the detection of the doubly 13C species in SgrB2 will be presented. This work was supported by the CNES and the Action sur Projets de l'INSU, PCMI. This work was also done under ANR-13-BS05-0008-02 IMOLABS. Support by the Deutsche Forschungsgemeinschaft via SFB 956, project B3 is acknowledged D.~R.~Johnson, et al., Astrophys.~J. 1977, 218, L370 A.~Belloche, et al., A&A 2013, 559, A47 A.M.~Daly, et al., Astrophys.~J. 2013, 768, 81 K.~Demyk, et al. A&A 2007 466, 255 Margulès, et al. A&A 2009, 493, 565 Belloche et al. 2014, Science, 345, 1584
Thoo, Yin Yin; Ho, Swee Kheng; Abas, Faridah; Lai, Oi Ming; Ho, Chun Wai; Tan, Chin Ping
2013-06-14
Antioxidants have been widely used in the food industry to enhance product quality by preventing oxidation of susceptible substances. This work was carried out to maximise the recovery of total phenolic content (TPC), total flavonoid content (TFC), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging capacity and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity from Morinda citrifolia fruit via modification of the ethanol concentration, extraction time and extraction temperature at minimal processing cost. The optimised conditions yielded values of 881.57 ± 17.74 mg GAE/100 g DW for TPC, 552.53 ± 34.16 mg CE/100 g DW for TFC, 799.20 ± 2.97 µmol TEAC/100 g DW for ABTS and 2,317.01 ± 18.13 µmol TEAC/100 g DW for DPPH were 75% ethanol, 40 min of time and 57 °C. The four responses did not differ significantly (p > 0.05) from predicted values, indicating that models obtained are suitable to the optimisation of extraction conditions for phenolics from M. citrifolia. The relative amounts of flavonoids were 0.784 ± 0.01 mg quercetin/g of extract and 1.021 ± 0.04 mg rutin/g of extract. On the basis of the results obtained, M. citrifolia extract can be used as a valuable bioactive source of natural antioxidants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Woodward, S.; Riaz, U.; Curtis, M.D.
1990-10-01
Reaction of CpNbCl{sub 4} (Cp = {eta}-C{sub 5}H{sub 5}) with (Pr{sup i}O){sub 2}P(S)(SH) in the presence of NEt{sub 3} yields CpNbCl{sub 3}(S{sub 2}P(S{sub 2}Pr{sup i}){sub 2}) (1). Reduction of 1 with Na/Hg affords the Nb-Nb-bonded complex CpNbCl({mu}-Cl){sub 2}Nb(S{sub 2}P(OR){sub 2})Cp (2). In refluxing toluene, (Pr{sup i}O){sub 2}P(S)(SH) with (Cp{prime}Mo(CO){sub 3}){sub 2} (Cp{prime} = {eta}-C{sub 5}H{sub 4}Me) gives cis-Cp{prime}Mo(CO){sub 2}(S{sub 2}P(OPr{sup i}){sub 2}) (3). Oxidation of 3 with I{sub 2} affords Cp{prime}MoI{sub 2}(CO)(S{sub 2}P(OPr{sup i}){sub 2}) (4). The crystal structures of 1-3 are compared. For 1, triclinic, P{bar 1}, a = 7.122 (3) {angstrom}, b = 11.365 (4) {angstrom}, c =more » 12.532 (4) {angstrom}, {alpha} = 77.38 (3){degree}, {beta} = 89.08 (3){degree}, {gamma} = 72.87 (3){degree}, V = 944.5 (8) {angstrom}{sup 3}. For 2, triclinic, P{bar 1}, a = 7.251 (3) {angstrom}, b = 12.386 (5) {angstrom}, c = 13.988 (5) {angstrom}, {alpha} = 102.66 (3){degree}, {beta} = 103.56 (3){degree}, {gamma} = 94.66 (3){degree}, V = 1180.0 (8) {angstrom}{sup 3}, Z = 2. For 3, orthorhombic, Pbca, a = 12.703 (3) {angstrom}, b = 16.707 (4) {angstrom}, c = 18.398 (4) {angstrom}, V = 3904.4 (17) {angstrom}{sup 3}, Z = 8.« less
The reaction mechanism of methyl-coenzyme M reductase: How an enzyme enforces strict binding order
Wongnate, Thanyaporn; Ragsdale, Stephen W.
2015-02-17
Methyl-coenzyme M reductase (MCR) is a nickel tetrahydrocorphinoid (coenzyme F430) containing enzyme involved in the biological synthesis and anaerobic oxidation of methane. MCR catalyzes the conversion of methyl-2-mercaptoethanesulfonate (methyl-SCoM) and N-7-mercaptoheptanoylthreonine phosphate (CoB 7SH) to CH 4 and the mixed disulfide CoBS-SCoM. In this study, the reaction of MCR from Methanothermobacter marburgensis, with its native substrates was investigated using static binding, chemical quench, and stopped-flow techniques. Rate constants were measured for each step in this strictly ordered ternary complex catalytic mechanism. Surprisingly, in the absence of the other substrate, MCR can bind either substrate; however, only one binary complex (MCR·methyl-SCoM)more » is productive whereas the other (MCR·CoB 7SH) is inhibitory. Moreover, the kinetic data demonstrate that binding of methyl-SCoM to the inhibitory MCR·CoB 7SH complex is highly disfavored ( Kd = 56 mM). However, binding of CoB 7SH to the productive MCR·methyl-SCoM complex to form the active ternary complex (CoB 7SH·MCR(Ni I)·CH 3SCoM) is highly favored ( Kd = 79 μM). Only then can the chemical reaction occur ( kobs = 20 s -1 at 25 °C), leading to rapid formation and dissociation of CH 4 leaving the binary product complex (MCR(Ni II)·CoB 7S -·SCoM), which undergoes electron transfer to regenerate Ni(I) and the final product CoBS-SCoM. In conclusion, this first rapid kinetics study of MCR with its natural substrates describes how an enzyme can enforce a strictly ordered ternary complex mechanism and serves as a template for identification of the reaction intermediates.« less
1993-09-01
Development 223 .4830* Manufacturing/Production 100 .4235* Management 105 .4091 * r values are statistically significant at p s 0.05. ** Overall mean complexity...by sequencing these items (e.g., #1,#2,#3,#4, and #5). They were instructed to place an "X" beside the step( s ) (i.e., information source) they did not...Worker( s ) Inside the Organization 26.9 45.3 11.5 5.6 0.6 10.1 Spoke With Colleagues Outside of the Organization 5.4 15.5 32.0 13.1 6.2 27.9 Used
Infrared Spectroscopy of C_6D_6-Rg_n(n=1,2)
NASA Astrophysics Data System (ADS)
George, Jobin; Yousefi, Mahdi; Rezaei, Mojtaba; McKellar, Bob; Moazzen-Ahmadi, Nasser
2014-06-01
Benzene-noble gas complexes were one of the earliest topics of interest in spectroscopic investigation of van der Waals (vdW) complexes. Smalley et al. observed C_6H_6-(He)1,2 vdW complexes in the late 1970s by means of electronic spectroscopy. A recent study on the same species was done by M. Hayashi et al. Here, we present the infrared observation of C_6D_6-Rg_n (n=1,2) with the rare gas being He, Ne, or Ar, in the regions of νb{12} fundamental band of C_6D_6 (˜2289 wn) and the νb{2} + νb{13} combination band (˜2275 wn) which are coupled by a Fermi resonance. The spectra were observed at a resolution of 60 MHz using a tunable optical parametric oscillator to probe a pulsed supersonic-jet expansion from a slit nozzle. In the case of C_6D_6-Rg dimers, the spectra were assigned to a symmetric top with C6v symmetry with the rare gas atom being located on the C6 symmetry axis. To observe C_6D_6-Rg_2 trimers, the nozzle was cooled using a closed-cycle methanol refrigerator and the spectra were simulated with a rotational temperature of 1.3K. The spectra of the C_6D_6-Rg_2 trimers were in agreement with a D6h symmetry structure, where the rare gas atoms are positioned above and below the C_6D_6 plane. Data analysis and observation are presently ongoing. S. M. Beck, M. G. Liverman, D. L. Monts and R. E. Smalley, J. Chem. Phys. 70, 232 (1979). M. Hayashi, Y. Ohshima, Chem. Phys. 419, 131 (2013).
NASA Astrophysics Data System (ADS)
Lalia, Boor Singh; Yoshimoto, Nobuko; Egashira, Minato; Morita, Masayuki
A binary mixture of triethylphosphate (TEP) and ethylene carbonate (EC) has been examined as a new non-flammable additive for ionic liquid-based electrolytes for lithium-ion batteries. The optimized electrolyte composition consists of 0.6 mol dm -3 (=M) LiTFSI in PP13TFSI mixed with TEP and EC in volume ratio of 80:10:10, where TFSI and PP13 denote bis(trifluoromethanesulfonyl)imide and N-methyl- N-propylpiperidinium, respectively. The ionic conductivity of PP13TFSI dissolving 0.4 M LiTFSI was improved from 8.2 × 10 -4 S cm -1 to 3.5 × 10 -3 S cm -1 (at 20 °C) with the addition of TEP and EC. The electrochemical behavior of 0.4 M LiTFSI/PP13TFSI with and without TEP and EC was studied by cyclic voltammetry, which showed no deteriorating effect by the addition of TEP and EC on the electrochemical window of PP13TFSI. The flammability of the electrolyte was tested by a direct flame test. The proposed ionic liquid-based electrolyte revealed significant improvements in the electrochemical charge-discharge characteristics for both graphite negative and LiMn 2O 4 positive electrodes.
QSAR Modeling and Prediction of Drug-Drug Interactions.
Zakharov, Alexey V; Varlamova, Ekaterina V; Lagunin, Alexey A; Dmitriev, Alexander V; Muratov, Eugene N; Fourches, Denis; Kuz'min, Victor E; Poroikov, Vladimir V; Tropsha, Alexander; Nicklaus, Marc C
2016-02-01
Severe adverse drug reactions (ADRs) are the fourth leading cause of fatality in the U.S. with more than 100,000 deaths per year. As up to 30% of all ADRs are believed to be caused by drug-drug interactions (DDIs), typically mediated by cytochrome P450s, possibilities to predict DDIs from existing knowledge are important. We collected data from public sources on 1485, 2628, 4371, and 27,966 possible DDIs mediated by four cytochrome P450 isoforms 1A2, 2C9, 2D6, and 3A4 for 55, 73, 94, and 237 drugs, respectively. For each of these data sets, we developed and validated QSAR models for the prediction of DDIs. As a unique feature of our approach, the interacting drug pairs were represented as binary chemical mixtures in a 1:1 ratio. We used two types of chemical descriptors: quantitative neighborhoods of atoms (QNA) and simplex descriptors. Radial basis functions with self-consistent regression (RBF-SCR) and random forest (RF) were utilized to build QSAR models predicting the likelihood of DDIs for any pair of drug molecules. Our models showed balanced accuracy of 72-79% for the external test sets with a coverage of 81.36-100% when a conservative threshold for the model's applicability domain was applied. We generated virtually all possible binary combinations of marketed drugs and employed our models to identify drug pairs predicted to be instances of DDI. More than 4500 of these predicted DDIs that were not found in our training sets were confirmed by data from the DrugBank database.
2011-01-01
10989). 13. SUPPLEMENTARY NOTES Journal article published in the Journal of Fluorine Chemistry, Vol. 132, Nov 2011. PA Case Number: 10989...TELEPHONE NUMBER (include area code) N/A Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 Journal of Fluorine Chemistry 132 (2011... Fluorine Chemistry jo ur n al h o mep ag e: www .e lsev ier . c om / loc ate / f luo r1. Introduction Eight new binary salts that pair the icosahedral
Hepatitis-C-virus-like internal ribosome entry sites displace eIF3 to gain access to the 40S subunit
NASA Astrophysics Data System (ADS)
Hashem, Yaser; Des Georges, Amedee; Dhote, Vidya; Langlois, Robert; Liao, Hstau Y.; Grassucci, Robert A.; Pestova, Tatyana V.; Hellen, Christopher U. T.; Frank, Joachim
2013-11-01
Hepatitis C virus (HCV) and classical swine fever virus (CSFV) messenger RNAs contain related (HCV-like) internal ribosome entry sites (IRESs) that promote 5'-end independent initiation of translation, requiring only a subset of the eukaryotic initiation factors (eIFs) needed for canonical initiation on cellular mRNAs. Initiation on HCV-like IRESs relies on their specific interaction with the 40S subunit, which places the initiation codon into the P site, where it directly base-pairs with eIF2-bound initiator methionyl transfer RNA to form a 48S initiation complex. However, all HCV-like IRESs also specifically interact with eIF3 (refs 2, 5, 6, 7, 9, 10, 11, 12), but the role of this interaction in IRES-mediated initiation has remained unknown. During canonical initiation, eIF3 binds to the 40S subunit as a component of the 43S pre-initiation complex, and comparison of the ribosomal positions of eIF3 and the HCV IRES revealed that they overlap, so that their rearrangement would be required for formation of ribosomal complexes containing both components. Here we present a cryo-electron microscopy reconstruction of a 40S ribosomal complex containing eIF3 and the CSFV IRES. Remarkably, although the position and interactions of the CSFV IRES with the 40S subunit in this complex are similar to those of the HCV IRES in the 40S-IRES binary complex, eIF3 is completely displaced from its ribosomal position in the 43S complex, and instead interacts through its ribosome-binding surface exclusively with the apical region of domain III of the IRES. Our results suggest a role for the specific interaction of HCV-like IRESs with eIF3 in preventing ribosomal association of eIF3, which could serve two purposes: relieving the competition between the IRES and eIF3 for a common binding site on the 40S subunit, and reducing formation of 43S complexes, thereby favouring translation of viral mRNAs.
Summary of Research Academic Departments.
1987-10-01
I.C ROBERT F. SMITH ADVISER: LIEUTENANT JOSEPH P. GILIO , USN - Heart Rate Treadmill MIDSHIPMAN 2, C JOHN M. SNIEFEN ADVISER: LIEUTENANT COMMANDER...I B t’ V" R S SGe’.chke, Miark 1., 131 Lander.. Rit, P, 218 Gibb, Arthur. fr., 100, 207, 2 10, 2 13 Langan, ’Thomas 1., 38 Gilio , Joseph P, 58 Lanzer
1975-06-01
3431 378 * 9 0S go9 391" I0*9 Is 3179 701 463 S09 831 736 *0" M1 Art 14M, *1 3us 1914 £00 St309 G17 494 so? AV ? A9l 1*7 64 13 * a£ oil 93 1969 100...AD-AO83 999 URS/MADIGAN-PRAEGER INC NEW YORK FIG 13 / 13 COMPREHENSIVE STUDY OF THE TOCKS ISLAND LAKE PROJECT AND ALTE--ETC(U) JUN 75 DACWSI75-C-0026... REPORT NUMBER 2S A RC1 11m a TR C OReu 4f** NUMS.em : 319a~ab boc mb The PROseIN OfGNZTO thi E stuDisDES to help decision maesdtrieftrA rsource n ege
Vohra, M S; Selimuzzaman, S M; Al-Suwaiyan, M S
2010-05-01
The main objective of the present study was to investigate the efficiency of titanium dioxide (TiO2) assisted photocatalytic degradation (PCD) process for the removal of ammonium-ammonia (NH4(+)-NH3) from the aqueous phase and in the presence of co-pollutants thiosulfate (S2O3(2-)) and p-cresol (C6H4CH3OH) under varying mixed conditions. For the NH4(+)-NH3 only PCD experiments, results showed higher NH4 -NH3 removal at pH 12 compared to pH 7 and 10. For the binary NH4(+)-NH3/S2O3(2-) studies the respective results indicated a significant lowering in NH4(+)-NH3 PCD in the presence of S2O32- at pH 7/12 whereas at pH 10 a marked increase in NH4(+)-NH3 removal transpired. A similar trend was noted for the p-cresol/NH4(+)-NH3 binary system. Comparing findings from the binary (NH4(+)-NH3/S2O3(2-) and p-cresol/NH4(+)-NH3) and tertiary (NH4(+)-NH3/S2O3(2-)/p-cresol) systems, at pH 10, showed fastest NH4(+)-NH3 removal transpiring for the tertiary system as compared to the binary systems, whereas both the binary systems indicated comparable NH4(+)-NH3 removal trends. The respective details have been discussed.
Schinzel, Sandra; Schraut, Johannes; Arbuznikov, Alexei V; Siegbahn, Per E M; Kaupp, Martin
2010-09-10
Metal and ligand hyperfine couplings of a previously suggested, energetically feasible Mn(4)Ca model cluster (SG2009(-1)) for the S(2) state of the oxygen-evolving complex (OEC) of photosystem II (PSII) have been studied by broken-symmetry density functional methods and compared with other suggested structural and spectroscopic models. This was carried out explicitly for different spin-coupling patterns of the S=1/2 ground state of the Mn(III)(Mn(IV))(3) cluster. By applying spin-projection techniques and a scaling of the manganese hyperfine couplings, computation of the hyperfine and nuclear quadrupole coupling parameters allows a direct evaluation of the proposed models in comparison with data obtained from the simulation of EPR, ENDOR, and ESEEM spectra. The computation of (55)Mn hyperfine couplings (HFCs) for SG2009(-1) gives excellent agreement with experiment. However, at the current level of spin projection, the (55)Mn HFCs do not appear sufficiently accurate to distinguish between different structural models. Yet, of all the models studied, SG2009(-1) is the only one with the Mn(III) site at the Mn(C) center, which is coordinated by histidine (D1-His332). The computed histidine (14)N HFC anisotropy for SG2009(-1) gives much better agreement with ESEEM data than the other models, in which Mn(C) is an Mn(IV) site, thus supporting the validity of the model. The (13)C HFCs of various carboxylates have been compared with (13)C ENDOR data for PSII preparations with (13)C-labelled alanine.
Constraints on particle acceleration in SS433/W50 from MAGIC and H.E.S.S. observations
NASA Astrophysics Data System (ADS)
MAGIC Collaboration; Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Arcaro, C.; Babić, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Berti, A.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Carosi, R.; Carosi, A.; Chatterjee, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Cumani, P.; da Vela, P.; Dazzi, F.; de Angelis, A.; de Lotto, B.; de Oña Wilhelmi, E.; di Pierro, F.; Doert, M.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher Glawion, D.; Elsaesser, D.; Engelkemeier, M.; Fallah Ramazani, V.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Gaug, M.; Giammaria, P.; Godinović, N.; Gora, D.; Griffiths, S.; Guberman, D.; Hadasch, D.; Hahn, A.; Hassan, T.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Ishio, K.; Konno, Y.; Kubo, H.; Kushida, J.; Kuveždić, D.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Oramas, A.; Majumdar, P.; Makariev, M.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Minev, M.; Mirzoyan, R.; Moralejo, A.; Moreno, V.; Moretti, E.; Munar-Adrover, P.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Nishijima, K.; Noda, K.; Nogués, L.; Paiano, S.; Palacio, J.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Pedaletti, G.; Peresano, M.; Perri, L.; Persic, M.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Garcia, J. R.; Reichardt, I.; Rhode, W.; Ribó, M.; Rico, J.; Saito, T.; Satalecka, K.; Schroeder, S.; Schweizer, T.; Shore, S. N.; Sillanpää, A.; Sitarek, J.; Šnidarić, I.; Sobczynska, D.; Stamerra, A.; Strzys, M.; Surić, T.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Torres, D. F.; Torres-Albà, N.; Treves, A.; Vanzo, G.; Vazquez Acosta, M.; Vovk, I.; Ward, J. E.; Will, M.; Wu, M. H.; Zarić, D.; H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; Dewilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'c.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de Los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Safi-Harb, S.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zywucka, N.
2018-04-01
Context. The large jet kinetic power and non-thermal processes occurring in the microquasar SS 433 make this source a good candidate for a very high-energy (VHE) gamma-ray emitter. Gamma-ray fluxes above the sensitivity limits of current Cherenkov telescopes have been predicted for both the central X-ray binary system and the interaction regions of SS 433 jets with the surrounding W50 nebula. Non-thermal emission at lower energies has been previously reported, indicating that efficient particle acceleration is taking place in the system. Aim. We explore the capability of SS 433 to emit VHE gamma rays during periods in which the expected flux attenuation due to periodic eclipses (Porb 13.1 days) and precession of the circumstellar disk (Ppre 162 days) periodically covering the central binary system is expected to be at its minimum. The eastern and western SS 433/W50 interaction regions are also examined using the whole data set available. We aim to constrain some theoretical models previously developed for this system with our observations. Methods: We made use of dedicated observations from the Major Atmospheric Gamma Imaging Cherenkov telescopes (MAGIC) and High Energy Spectroscopic System (H.E.S.S.) of SS 433 taken from 2006 to 2011. These observation were combined for the first time and accounted for a total effective observation time of 16.5 h, which were scheduled considering the expected phases of minimum absorption of the putative VHE emission. Gamma-ray attenuation does not affect the jet/medium interaction regions. In this case, the analysis of a larger data set amounting to 40-80 h, depending on the region, was employed. Results: No evidence of VHE gamma-ray emission either from the central binary system or from the eastern/western interaction regions was found. Upper limits were computed for the combined data set. Differential fluxes from the central system are found to be ≲ 10-12-10-13 TeV-1 cm-2 s-1 in an energy interval ranging from few × 100 GeV to few TeV. Integral flux limits down to 10-12-10-13 ph cm-2 s-1 and 10-13-10-14 ph cm-2 s-1 are obtainedat 300 and 800 GeV, respectively. Our results are used to place constraints on the particle acceleration fraction at the inner jetregions and on the physics of the jet/medium interactions. Conclusions: Our findings suggest that the fraction of the jet kinetic power that is transferred to relativistic protons must be relatively small in SS 433, qp ≤ 2.5 × 10-5, to explain the lack of TeV and neutrino emission from the central system. At the SS 433/W50 interface, the presence of magnetic fields ≳10 μG is derived assuming a synchrotron origin for the observed X-ray emission. This also implies the presence of high-energy electrons with Ee- up to 50 TeV, preventing an efficient production of gamma-ray fluxes in these interaction regions.
The Study of Acenaphthene and its Complexation with Water
NASA Astrophysics Data System (ADS)
Steber, Amanda; Perez, Cristobal; Rijs, Anouk; Schnell, Melanie
2016-06-01
Acenaphthene (Ace) is a three ring polycyclic aromatic hydrocarbon (PAH), which consists of naphthalene and a non-aromatic five member ring. Ace has been previously been studied by microwave spectroscopy where the rotational constants were reported[1]. New measurements from 2-8 GHz using chirped pulse-Fourier transform microwave spectroscopy (CP-FTMW) will be presented. The high sensitivity achieved enabled us to observe all 13C isotopologues in natural abundance and determine the Kraitchman substitution structure. The spectra of Ace complexed with water and H218O were also recorded at this frequency range. From these spectra, we have been able to assign the complexes Ace-(H2O)n, n=1-3 and (Ace)2-H2O and experimentally derive the O-atom position of the H2O. The Ace-(H2O)3 complex is especially interesting as the water aggregate forms a slightly distorted cyclic water trimer from that observed in the IR[2]. These complexes could give insight about the formation of ice grains in the interstellar medium. [1] Thorwirth, S., Theulé, P., Gottlieb, C.A., McCarthy, M.C., Thaddeus, P. Astrophys. J., 662, 1309-1314, 2007. [2] Keutsch, F.N., Cruzan, J.D., Saykally, R.J. Chem. Rev., 103, 2533-2577, 2003.
13. Architectural First Floor Plan Buildings 185189 D, U.S. Atomic ...
13. Architectural First Floor Plan Buildings 185-189 D, U.S. Atomic Energy Commission, General Electric Company, Dwg. NO. H-1-11825, 1959. - D-Reactor Complex, Deaeration Plant-Refrigeration Buildings, Area 100-D, Richland, Benton County, WA
A Search for Low Mass Stars and Substellar Companions and A Study of Circumbinary Gas and Dust Disks
NASA Astrophysics Data System (ADS)
Rodriguez, David R.
2011-01-01
We have searched for nearby low-mass stars and brown dwarfs and have studied the planet-forming environment of binary stars. We have carried out a search for young, low-mass stars in nearby stellar associations using X-ray and UV source catalogs. We discovered a new technique to identify 10-100 Myr-old low-mass stars within 100 pc of the Earth using GALEX-optical/near-IR data. We present candidate young stars found by applying this new method in the 10 Myr old TW Hydrae and Scorpius-Centaurus associations. In addition, we have searched for the coolest brown dwarf class: Y-dwarfs, expected to appear at temperatures <500 K. Using wide-field near infrared imaging with ground (CTIO, Palomar, KPNO) and space (Spitzer, AKARI) observatories, we have looked for companions to nearby, old (2 Gyr or older), high proper motion white dwarfs. We present results for Southern Hemisphere white dwarfs. Additionally, we have characterized how likely planet formation occurs in binary star systems. While 20% of planets have been discovered around one member of a binary system, these binaries have semi-major axes larger than 20 AU. We have performed an AO and spectroscopic search for binary stars among a sample of known debris disk stars, which allows us to indirectly study planet formation and evolution in binary systems. As a case study, we examined the gas and dust present in the circumbinary disk around V4046 Sagittarii, a 2.4-day spectroscopic binary. Our results demonstrate it is unlikely that planets can form in binaries with stellar semi-major axes of 10s of AU. This research has been funded by a NASA ADA grant to UCLA and RIT.
Imaging the Molecular Disk Orbiting the Twin Suns of V4046 Sgr
NASA Astrophysics Data System (ADS)
Rodriguez, David R.; Kastner, J. H.; Wilner, D. J.; Zuckerman, B.
2009-05-01
V4046 Sgr is a 12 Myr-old spectroscopic binary with a period of 2.4 days. At a distance of 73 pc (Torres et al. 2008), it is the second closest classical T Tauri star to the Earth after TW Hydra. Previously, rotational transitions of CO, HCO+, CN, and HCN were detected with the 30m IRAM telescope (Kastner et al. 2008). The double peaked CO profiles can be fit by a model invoking a Keplerian disk with outer radius of 250 AU that is viewed at an inclination of 35 degrees. The CO line profile was asymmetric, with the redshifted emission peak in both C-12 and C-13 brighter than the blueshifted peak. We have used the SMA to spatially resolve the J=2-1 CO emission line and the 230 GHz continuum. The CO channel maps show a disk consistent with Keplerian rotation. At the velocity of the redshifted emission peak, these observations reveal enhanced CO emission a few arcseconds to the southwest of the binary. A question arises as to whether this enhanced CO emission is associated with a third star in the system. According to the analysis of Tokovinin et al. (2006), the probability that a binary with a 2.4 day period has an associated tertiary star is essentially 100%. We searched archival Chandra and HST (ACS and NICMOS) images in the vicinity of V4046 Sgr to look for a star at the position of the enhanced CO emission. While there is a star in the HST ACS images approximately coincident with the enhanced CO emission, our preliminary analysis suggests that this star is not physically associated with V4046 Sgr. We will present a detailed discussion of the SMA results. This work has been partially supported by a NASA ADA grant to RIT and UCLA.
S100A8 Contributes to Drug Resistance by Promoting Autophagy in Leukemia Cells
Yang, Minghua; Zeng, Pei; Kang, Rui; Yu, Yan; Yang, Liangchun; Tang, Daolin; Cao, Lizhi
2014-01-01
Autophagy is a double-edged sword in tumorigenesis and plays an important role in the resistance of cancer cells to chemotherapy. S100A8 is a member of the S100 calcium-binding protein family and plays an important role in the drug resistance of leukemia cells, with the mechanisms largely unknown. Here we report that S100A8 contributes to drug resistance in leukemia by promoting autophagy. S100A8 level was elevated in drug resistance leukemia cell lines relative to the nondrug resistant cell lines. Adriamycin and vincristine increased S100A8 in human leukemia cells, accompanied with upregulation of autophagy. RNA interference-mediated knockdown of S100A8 restored the chemosensitivity of leukemia cells, while overexpression of S100A8 enhanced drug resistance and increased autophagy. S100A8 physically interacted with the autophagy regulator BECN1 and was required for the formation of the BECN1-PI3KC3 complex. In addition, interaction between S100A8 and BECN1 relied upon the autophagic complex ULK1-mAtg13. Furthermore, we discovered that exogenous S100A8 induced autophagy, and RAGE was involved in exogenous S100A8-regulated autophagy. Our data demonstrated that S100A8 is involved in the development of chemoresistance in leukemia cells by regulating autophagy, and suggest that S100A8 may be a novel target for improving leukemia therapy. PMID:24820971
PAM-4 Signaling over VCSELs with 0.13µm CMOS Chip Technology
NASA Astrophysics Data System (ADS)
Cunningham, J. E.; Beckman, D.; Zheng, Xuezhe; Huang, Dawei; Sze, T.; Krishnamoorthy, A. V.
2006-12-01
We present results for VCSEL based links operating PAM-4 signaling using a commercial 0.13µm CMOS technology. We perform a complete link analysis of the Bit Error Rate, Q factor, random and deterministic jitter by measuring waterfall curves versus margins in time and amplitude. We demonstrate that VCSEL based PAM 4 can match or even improve performance over binary signaling under conditions of a bandwidth limited, 100meter multi-mode optical link at 5Gbps. We present the first sensitivity measurements for optical PAM-4 and compare it with binary signaling. Measured benefits are reconciled with information theory predictions.
PAM-4 Signaling over VCSELs with 0.13microm CMOS Chip Technology.
Cunningham, J E; Beckman, D; Zheng, Xuezhe; Huang, Dawei; Sze, T; Krishnamoorthy, A V
2006-12-11
We present results for VCSEL based links operating PAM-4 signaling using a commercial 0.13microm CMOS technology. We perform a complete link analysis of the Bit Error Rate, Q factor, random and deterministic jitter by measuring waterfall curves versus margins in time and amplitude. We demonstrate that VCSEL based PAM-4 can match or even improve performance over binary signaling under conditions of a bandwidth limited, 100meter multi-mode optical link at 5Gbps. We present the first sensitivity measurements for optical PAM-4 and compare it with binary signaling. Measured benefits are reconciled with information theory predictions.
NASA Astrophysics Data System (ADS)
Parsaee, Zohreh; Mohammadi, Khosro
2017-06-01
Some new macrocyclic bridged dianilines tetradentate with N4coordination sphere Schiff base ligands and their nickel(II)complexes with general formula [{Ni2LCl4} where L = (C20H14N2X)2, X = SO2, O, CH2] have been synthesized. The compounds have been characterized by FT-IR, 1H and 13C NMR, mass spectroscopy, TGA, elemental analysis, molar conductivity and magnetic moment techniques. Scanning electron microscopy (SEM) shows nano-sized structures under 100 nm for nickel (II) complexes. NiO nanoparticle was achieved via the thermal decomposition method and analyzed by FT-IR, SEM and X-ray powder diffraction which indicates closeaccordance to standard pattern of NiO nanoparticle. All the Schiff bases and their complexes have been detected in vitro both for antibacterial activity against two gram-negative and two gram-positive bacteria. The nickel(II) complexes were found to be more active than the free macrocycle Schiff bases. In addition, computational studies of three ligands have been carried out at the DFT-B3LYP/6-31G+(d,p) level of theory on the spectroscopic properties, including IR, 1HNMR and 13CNMR spectroscopy. The correlation between the theoretical and the experimental vibrational frequencies, 1H NMR and 13C NMR of the ligands were 0.999, 0.930-0.973 and 0.917-0.995, respectively. Also, the energy gap was determined and by using HOMO and LUMO energy values, chemical hardness-softness, electronegativity and electrophilic index were calculated.
Kreidler, Anna-Maria; Benz, Roland; Barth, Holger
2017-03-01
The pathogenic bacteria Clostridium botulinum and Bacillus anthracis produce the binary protein toxins C2 and lethal toxin (LT), respectively. These toxins consist of a binding/transport (B 7 ) component that delivers the separate enzyme (A) component into the cytosol of target cells where it modifies its specific substrate and causes cell death. The B 7 components of C2 toxin and LT, C2IIa and PA 63 , respectively, are ring-shaped heptamers that bind to their cellular receptors and form complexes with their A components C2I and lethal factor (LF), respectively. After receptor-mediated endocytosis of the toxin complexes, C2IIa and PA 63 insert into the membranes of acidified endosomes and form trans-membrane pores through which C2I and LF translocate across endosomal membranes into the cytosol. C2IIa and PA 63 also form channels in planar bilayer membranes, and we used this approach earlier to identify chloroquine as a potent blocker of C2IIa and PA 63 pores. Here, a series of chloroquine derivatives was investigated to identify more efficient toxin inhibitors with less toxic side effects. Chloroquine, primaquine, quinacrine, and fluphenazine blocked C2IIa and PA 63 pores in planar lipid bilayers and in membranes of living epithelial cells and macrophages, thereby preventing the pH-dependent membrane transport of the A components into the cytosol and protecting cells from intoxication with C2 toxin and LT. These potent inhibitors of toxin entry underline the central role of the translocation pores for cellular uptake of binary bacterial toxins and as relevant drug targets, and might be lead compounds for novel pharmacological strategies against severe enteric diseases and anthrax.
NASA Astrophysics Data System (ADS)
Dymond, J. H.; Awan, M. A.; Glen, N. F.; Isdale, J. D.
1991-05-01
A two-coil self-centering falling-body viscometer has been used to measure viscosity coefficients for acetonitrile and three binary mixtures of toluene+ acetonitrile at 25, 50, 75, and 100°C and pressures up to 500 MPa. The results for acetonitrile can be interpreted by an approach based on hard-sphere theory, with a roughness factor of 1.46. The binary-mixture data are well represented by the Grunberg and Nissan equation with a mixing parameter which is pressure and temperature dependent but composition independent.
Natural Time Analysis and Complex Networks
NASA Astrophysics Data System (ADS)
Sarlis, Nicholas; Skordas, Efthimios; Lazaridou, Mary; Varotsos, Panayiotis
2013-04-01
Here, we review the analysis of complex time series in a new time domain, termed natural time, introduced by our group [1,2]. This analysis conforms to the desire to reduce uncertainty and extract signal information as much as possible [3]. It enables [4] the distinction between the two origins of self-similarity when analyzing data from complex systems, i.e., whether self-similarity solely results from long-range temporal correlations (the process's memory only) or solely from the process's increments infinite variance (heavy tails in their distribution). Natural time analysis captures the dynamical evolution of a complex system and identifies [5] when the system enters a critical stage. Hence, this analysis plays a key role in predicting forthcoming catastrophic events in general. Relevant examples, compiled in a recent monograph [6], have been presented in diverse fields, including Solid State Physics [7], Statistical Physics (for example systems exhibiting self-organized criticality [8]), Cardiology [9,10], Earth Sciences [11] (Geophysics, Seismology), Environmental Sciences (e.g. see Ref. [12]), etc. Other groups have proposed and developed a network approach to earthquake events with encouraging results. A recent study [13] reveals that this approach is strengthened if we combine it with natural time analysis. In particular, we find [13,14] that the study of the spatial distribution of the variability [15] of the order parameter fluctuations, defined in natural time, provides important information on the dynamical evolution of the system. 1. P. Varotsos, N. Sarlis, and E. Skordas, Practica of Athens Academy, 76, 294-321, 2001. 2. P.A. Varotsos, N.V. Sarlis, and E.S. Skordas, Phys. Rev. E, 66, 011902 , 2002. 3. S. Abe, N.V. Sarlis, E.S. Skordas, H.K. Tanaka and P.A. Varotsos, Phys. Rev. Lett. 94, 170601, 2005. 4. P.A. Varotsos, N.V. Sarlis, E.S. Skordas, H.K. Tanaka and M.S. Lazaridou, Phys. Rev. E, 74, 021123, 2006. 5. P.Varotsos, N. V. Sarlis, E. S. Skordas, S. Uyeda, and M. Kamogawa, Proc Natl Acad Sci USA 108, 11361-11364, 2011. 6. P.A.Varotsos, N.V.Sarlis and E.S.Skordas, NATURAL TIME ANALYSIS: THE NEW VIEW OF TIME. Precursory Seismic Electric Signals, Earthquakes and other Complex Time-Series, Springer-Verlag, Berlin, Heidelberg, 2011. 7. N.V. Sarlis, P.A. Varotsos, and E.S. Skordas, Phys. Rev. B 73, 054504, 2006. 8. N. V. Sarlis, E. S. Skordas, and P. A. Varotsos, EPL 96, 28006, 2011. 9. P.A. Varotsos, N.V. Sarlis, E.S. Skordas, and M.S. Lazaridou, Appl. Phys. Lett. 91, 064106, 2007. 10. N.V. Sarlis, E.S. Skordas and P.A. Varotsos, EuroPhysics Letters EPL, 87, 18003, (2009). 11. P.A. Varotsos, N. V. Sarlis and E. S. Skordas, EPL 96 59002, 2011; 99, 59001 2012; 100 39002, 2012. 12. C.A. Varotsos and C. Tzanis, Atmospheric Environment 47, 428-434, 2012. 13. P. Varotsos, N. Sarlis, E. Skordas and M. Lazaridou, Tectonophysics (DOI 10.1016/j.tecto.2012.12.020). 14. P. Varotsos, N. Sarlis and E. Skordas, EPL to be published. 15. N. V. Sarlis, E. S. Skordas and P. A. Varotsos, EPL 91, 59001, 2010.
Allostery Mediates Ligand Binding to Grb2 Adaptor in a Mutually Exclusive Manner
McDonald, Caleb B.; El Hokayem, Jimmy; Zafar, Nawal; Balke, Jordan E.; Bhat, Vikas; Mikles, David C.; Deegan, Brian J.; Seldeen, Kenneth L.; Farooq, Amjad
2012-01-01
Allostery plays a key role in dictating the stoichiometry and thermodynamics of multi-protein complexes driving a plethora of cellular processes central to health and disease. Herein, using various biophysical tools, we demonstrate that although Sos1 nucleotide exchange factor and Gab1 docking protein recognize two non-overlapping sites within the Grb2 adaptor, allostery promotes the formation of two distinct pools of Grb2-Sos1 and Grb2-Gab1 binary signaling complexes in concert in lieu of a composite Sos1-Grb2-Gab1 ternary complex. Of particular interest is the observation that the binding of Sos1 to the nSH3 domain within Grb2 sterically blocks the binding of Gab1 to the cSH3 domain and vice versa in a mutually exclusive manner. Importantly, the formation of both the Grb2-Sos1 and Grb2-Gab1 binary complexes is governed by a stoichiometry of 2:1, whereby the respective SH3 domains within Grb2 homodimer bind to Sos1 and Gab1 via multivalent interactions. Collectively, our study sheds new light on the role of allostery in mediating cellular signaling machinery. PMID:23334917
Electron Impact K-shell Ionization of Atomic Targets
NASA Astrophysics Data System (ADS)
Saha, Bidhan; Basak, Arun K.; Alfaz Uddin, M.; Patoary, A. A. R.
2008-05-01
In spite of considerable progress -both theoretically and experimentally- recently in evaluating accurate K-shell ionization cross sections that play a decisive role for quantitative analyses using (i) electron probe microanalysis, (ii) Auger electron spectroscopy and (iii) electron energy loss spectra, attempts are still continuing to search for a model that can easily generate reliable cross sections for a wide range of energies and for various targets needed for plasma modeling code We report few modifications of the widely used binary encounter approximation (BEA) [1,2] and have tested by evaluating the electron impact K-shell ionization of few neutral targets at various projectile energies. Details will be presented at the meeting. [1] M. Gryziniski, Phys. Rev. A 138, 336 (1965); [2] L. Vriens, Proc. Phys. Soc. (London) 89, 13, (1966). [3M. A. Uddin , A. K. F. Haque, M. M. Billah, A. K. Basak, K, R, Karim and B. C. Saha, ,Phys. Rev. A 71,032715 (2005); [4] M. A. Uddin, A. K. Basak, and B. C. Saha, Int. J. Quan. Chem 100, 184 (2004).
Luo, Honglin; Li, Wei; Ao, Haiyong; Li, Gen; Tu, Junpin; Xiong, Guangyao; Zhu, Yong; Wan, Yizao
2017-07-01
Three-dimensional (3D) nanofibrous scaffolds hold great promises in tissue engineering and regenerative medicine. In this work, for the first time, 3D SiO 2 -CaO binary glass nanofibrous scaffolds have been fabricated via a combined method of template-assisted sol-gel and calcination by using bacterial cellulose as the template. SEM with EDS, TEM, and AFM confirm that the molar ratio of Ca to Si and fiber diameter of the resultant SiO 2 -CaO nanofibers can be controlled by immersion time in the solution of tetraethyl orthosilicate and ethanol. The optimal immersion time was 6h which produced the SiO 2 -CaO binary glass containing 60at.% Si and 40at.% Ca (named 60S40C). The fiber diameter of 60S40C scaffold is as small as 29nm. In addition, the scaffold has highly porous 3D nanostructure with dominant mesopores at 10.6nm and macropores at 20μm as well as a large BET surface area (240.9m 2 g -1 ), which endow the 60S40C scaffold excellent biocompatibility and high ALP activity as revealed by cell studies using osteoblast cells. These results suggest that the 60S40C scaffold has great potential in bone tissue regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.
Calculation of the 13C NMR shieldings of the C0 2 complexes of aluminosilicates
NASA Astrophysics Data System (ADS)
Tossell, J. A.
1995-04-01
13C NMR shieldings have been calculated using the random-phase-approximation, localized-orbital local-origins version of ab initio coupled Hartree-Fuck perturbation theory for CO 2 and and for several complexes formed by the reaction of CO 2 with molecular models for aluminosilicate glasses, H 3TOT'H3 3-n, T,T' = Si,Al. Two isomeric forms of the CO 2-aluminosilicate complexes have been considered: (1) "CO 2-like" complexes, in which the CO 2 group is bound through carbon to a bridging oxygen and (2) "CO 3-like" complexes, in which two oxygens of a central CO 3 group form bridging bonds to the two TH 3 groups. The CO 2-like isomer of CO 2-H 3SiOSiH 3 is quite weakly bonded and its 13C isotropic NMR shielding is almost identical to that in free CO 2. As Si is progressively replaced by Al in the - H terminated aluminosilicate model, the CO 2-like isomers show increasing distortion from the free CO 2 geometry and their 13C NMR shieldings decrease uniformly. The calculated 13C shielding value for H 3AlO(CO 2)AlH 3-2 is only about 6 ppm larger than that calculated for point charge stabilized CO 3-2. However, for a geometry of H 3SiO(CO 2) AlH 3-1, in which the bridging oxygen to C bond length has been artificially increased to that found in the - OH terminated cluster (OH) 3SiO(CO 2)Al(OH) 3-1, the calculated 13C shielding is almost identical to that for free CO 2. The CO 3-like isomers of the CO 2-aluminosili-cate complexes show carbonate like geometries and 13C NMR shieldings about 4-9 ppm larger than those of carbonate for all T,T' pairs. For the Si,Si tetrahedral atom pair the CO 2-like isomer is more stable energetically, while for the Si,Al and Al,Al cases the CO 3-like isomer is more stable. Addition of Na + ions to the CO 3-2 or H 3AlO(CO 2)AlH 3-2 complexes reduces the 13C NMR shieldings by about 10 ppm. Complexation with either Na + or CO 2 also reduces the 29Si NMR shieldings of the aluminosilicate models, while the changes in 27Al shielding with Na + or CO 2 complexation are much smaller. Complexation with CO 2 greatly increases the electric field gradient at the bridging oxygen of H 3AlOAlH 3-2, raising it to a value similar to that found for SiOSi linkages. Comparison of these results with the experimental 13C NMR spectra support the formation of CO 2-like complexes at SiOSi bridges in albite glasses and CO 3-like complexes at SiOAl and AlOAl bridges in albite and nepheline glasses. Changes in the calculated shieldings as Na + ions are added to the complexes suggest that some of the observed complexes may be similar in their CO 2-aluminosilicate interactions, but different with respect to the positions of the charge-compensating Na + ions.
The Beta Pictoris Phenomenon in Young Stars With Accreting Gas
NASA Technical Reports Server (NTRS)
Grady, Carol A.
1999-01-01
Program Hae2BPIC resulted in usable ISO spectra of three young, Herbig Ae stars: HR 5999 (A7e, t=0.6 Myr), SV Cep (al-2e, t=1-3 Myr), and MW Vul (Al-2e, t=1-3 Myr). While too small a sample to pursue our original goal of surveying the silicate emission in these young, protoplanetary disk systems, comparison of these data with ground-based IR spectra, and published ISO observations of other HAe stars (especially the posters at PPIV) reveals the following: The known binary stars in the sample show signatures of partially crystal line silicate features by t=0.6 Myr, at an epoch when ostensibly single Herbig Ae stars have substantially stronger silicate emission dominated by amorphous grains. The known binary stars also show deficits in the optically thick continuum flux relative to coeval single stars. Comparison of ISO spectra indicates that the flux deficit seen in WD 163296 over 10-100 microns relative to AB Aur reflects a real deficit of material interior to 300.
Generation and Termination of Binary Decision Trees for Nonparametric Multiclass Classification.
1984-10-01
O M coF=F;; UMBER2. GOVT ACCE5SION NO.1 3 . REC,PINS :A7AL:,G NUMBER ( ’eneration and Terminat_,on :)f Binary D-ecision jC j ik; Trees for Nonnararetrc...1-I . v)IAMO 0~I4 EDvt" O F I 00 . 3 15I OR%.OL.ETL - S-S OCTOBER 1984 LIDS-P-1411 GENERATION AND TERMINATION OF BINARY DECISION TREES FOR...minimizes the Bayes risk. Tree generation and termination are based on the training and test samples, respectively. 0 0 0/ 6 0¢ A 3 I. Introduction We state
Spectral properties of binary asteroids
NASA Astrophysics Data System (ADS)
Pajuelo, Myriam; Birlan, Mirel; Carry, Benoît; DeMeo, Francesca E.; Binzel, Richard P.; Berthier, Jérôme
2018-04-01
We present the first attempt to characterize the distribution of taxonomic class among the population of binary asteroids (15% of all small asteroids). For that, an analysis of 0.8-2.5{μ m} near-infrared spectra obtained with the SpeX instrument on the NASA/IRTF is presented. Taxonomic class and meteorite analog is determined for each target, increasing the sample of binary asteroids with known taxonomy by 21%. Most binary systems are bound in the S-, X-, and C- classes, followed by Q and V-types. The rate of binary systems in each taxonomic class agrees within uncertainty with the background population of small near-Earth objects and inner main belt asteroids, but for the C-types which are under-represented among binaries.
Near-Earth Asteroid 2005 CR37: Radar Images and Photometry of a Candidate Contact Binary
NASA Technical Reports Server (NTRS)
Benner, Lance A. M.; Nolan, Michael C.; Ostro, Steven J.; Giorgini, Jon D.; Pray, Donald P.; Harris, Alan W.; Magri, Christopher; Margot, Jean-Luc
2006-01-01
Arecibo (2380 MHz, 13 cm) radar observations of 2005 CR37 provide detailed images of a candidate contact binary: a 1.8-km-long, extremely bifurcated object. Although the asteroid's two lobes are round, there are regions of modest topographic relief, such as an elevated, 200-m-wide facet, that suggest that the lobes are geologically more complex than either coherent fragments or homogeneous rubble piles. Since January 1999, about 9% of NEAs larger than approx.200 m imaged by radar can be described as candidate contact binaries.
1991-03-29
S) A-927 BAFB-0427 22159-4 13-C-2SB (S) A-929 BAFB- 0428 22159-5 13-C-2SB (S) A-930 BAFB-0256 21872-11 13-C-2SB (S) A-931 BAFB-0429 22159-6 13-C-2SB (S...16 18-C-19SS (S) A-1305 BAFB-0021 21621-17 18-C-20SS (S) A- 1307 BAFB-0022 21621-18 18-C-20SS (S) A-1309 BAFB-0024 21621-20 18-C-21SS (S) A-1311 BAFB...ASA#9) 21.0 N/A MERCURY (SW7471) (Resampled for this analysis. See BAFB-0427 and BAFB- 0428 ) TFH-DIESEL (TFH-DIESEL) ə.3 1.3 mg/kg. (non-detect) TFH
Dissolved carbon dynamics in large boreal rivers from eastern Canada following their impoundment
NASA Astrophysics Data System (ADS)
Helie, J.; Rosa, E.; Lalonde, A.; Hillaire-Marcel, C.
2009-12-01
The carbon cycling in Canadian boreal environments is the focus of a growing number of investigations mainly because of the importance of hydropower and its potential in the area. Here, we document the behaviour of dissolved inorganic and organic carbon as well as particulate organic carbon (DIC-DOC-POC henceforth) in 5 impounded and 2 pristine river systems (respectively: La Grande 3400 m 3s-1, Eastmain 990 m3s-1, St. Lawrence 12 100 m3s-1, Ottawa 1950 m3s-1, Nelson 2370 m3s-1; Great Whales 680 m3s-1 and Koksoak 1895 m3s-1) river systems. These major rivers were sampled monthly at their outlet for one year except at the St. Lawrence River that has been sampled since June of 1997 on a bi-weekly basis. Complementary synoptic surveys were undertaken in August 2008 on the La Grande and Great Whales Rivers. When sampling, water temperature, pH, alkalinity and specific conductivity were measured. Samples were collected for the analysis of i) major ions concentrations; ii) δ13C and concentration of DIC, DOC and POC); iii) δ18O and δ2H of the water molecule; and iv) U series and Sr isotopes. In all the sampled river systems, POC concentrations were at least an order of magnitude smaller than the dissolved forms. Rivers draining carbonates bedrocks (St.Lawrence and Nelson Rivers) present higher concentrations and δ13C-DIC values linked to carbonate dissolution in soils. Conversely, rivers draining silicate-rich watersheds present lower δ13C- DIC values linked to the production of an isotopically light CO2 through oxidation of organic matter in soils and that of soil-derived DOC along river courses. However, isotopic composition of DIC in impounded rivers draining silicate catchments indicate significant CO2 degassing and some isotopic exchange with atmospheric CO2 in reservoirs. A relatively strong relationship is observed between pCO2 and δ13C-DIC across the studied river systems suggesting a continuum between the production of CO2 through DOM oxidation and CO2 degassing. A relationship is also observed between δ13C-DIC values and [DOC]/[DIC] suggesting here that the more DOC is available for degradation, the more it will be oxidized to dissolved CO2. A striking feature of boreal systems is the homogeneity of the isotopic composition of its DOC (-27.4±0.2‰ vs. V-PDB). Moreover, C/N ratios and 14C activities >100% (vs. "modern" carbon) of bulk dissolved organic matter (MOD) measured in the impounded La Grande River also lead to conclude that that this DOC, mostly fresh and young, has a low overall residence time in the catchment basin.
NASA Astrophysics Data System (ADS)
Coutens, A.; Jørgensen, J. K.; van der Wiel, M. H. D.; Müller, H. S. P.; Lykke, J. M.; Bjerkeli, P.; Bourke, T. L.; Calcutt, H.; Drozdovskaya, M. N.; Favre, C.; Fayolle, E. C.; Garrod, R. T.; Jacobsen, S. K.; Ligterink, N. F. W.; Öberg, K. I.; Persson, M. V.; van Dishoeck, E. F.; Wampfler, S. F.
2016-05-01
Formamide (NH2CHO) has previously been detected in several star-forming regions and is thought to be a precursor for different prebiotic molecules. Its formation mechanism is still debated, however. Observations of formamide, related species, and their isopotologues may provide useful clues to the chemical pathways leading to their formation. The Protostellar Interferometric Line Survey (PILS) represents an unbiased, high angular resolution and sensitivity spectral survey of the low-mass protostellar binary IRAS 16293-2422 with the Atacama Large Millimeter/submillimeter Array (ALMA). For the first time, we detect the three singly deuterated forms of NH2CHO (NH2CDO, cis- and trans-NHDCHO), as well as DNCO towards the component B of this binary source. The images reveal that the different isotopologues are all present in the same region. Based on observations of the 13C isotopologues of formamide and a standard 12C/13C ratio, the deuterium fractionation is found to be similar for the three different forms with a value of about 2%. The DNCO/HNCO ratio is also comparable to the D/H ratio of formamide (~1%). These results are in agreement with the hypothesis that NH2CHO and HNCO are chemically related through grain-surface formation.
17 CFR 240.3a68-4 - Regulation of mixed swaps.
Code of Federal Regulations, 2013 CFR
2013-04-01
....S.C. 78c(a)(68)(D)). (b) Regulation of bilateral uncleared mixed swaps entered into by dually...(f) and 12; (B) Enforcement: 7 U.S.C. 2(a)(1)(B), 6(b), 6b, 6c, 6s(h)(1)(A), 6s(h)(4)(A), 9, 13b, 13a-1, 13a-2, 13, 13c(a), 13c(b), 15 and 26; (C) Reporting to a swap data repository: 7 U.S.C. 6r; (D...
Coordinated observations of interacting peculiar red giant binaries, 2
NASA Technical Reports Server (NTRS)
Ake, T.
1995-01-01
IUE and H alpha observations continued on a two-year program to monitor the UV variability of three interacting peculiar red giant (PRG) binaries, HD 59643 (C6,s), HD 35155 (S3/2), and HR 1105 (S3.5/2.5). All of these systems were suspected to involve accretion of material from the PRG to a white-dwarf secondary, based mainly on previous IUE investigations. They were primary candidates from earlier surveys of PRG's to test the hypothesis that the Tc-poor PRG's are formed as a result of mass transfer from a secondary component rather than from internal thermal pulsing while on the asymptotic red giant branch.
Riswan Ahamed, Mohamed A.; Azarudeen, Raja S.; Kani, N. Mujafar
2014-01-01
Terpolymer of 2-amino-6-nitro-benzothiazole-ethylenediamine-formaldehyde (BEF) has been synthesized and characterized by elemental analysis and various spectral techniques like FTIR, UV-Visible, and 1H and 13C-NMR. The terpolymer metal complexes were prepared with Cu2+, Ni2+, and Zn2+ metal ions using BEF terpolymer as a ligand. The complexes have been characterized by elemental analysis and IR, UV-Visible, ESR, 1H-NMR, and 13C-NMR spectral studies. Gel permeation chromatography was used to determine the molecular weight of the ligand. The surface features and crystalline behavior of the ligand and its complexes were analyzed by scanning electron microscope and X-ray diffraction methods. Thermogravimetric analysis was used to analyze the thermal stability of the ligand and its metal complexes. Kinetic parameters such as activation energy (E a) and order of reaction (n) and thermodynamic parameters, namely, ΔS, ΔF, S*, and Z, were calculated using Freeman-Carroll (FC), Sharp-Wentworth (SW), and Phadnis-Deshpande (PD) methods. Thermal degradation model of the terpolymer and its metal complexes was also proposed using PD method. Biological activities of the ligand and its complexes were tested against Shigella sonnei, Escherichia coli, Klebsiella species, Staphylococcus aureus, Bacillus subtilis, and Salmonella typhimurium bacteria and Aspergillus flavus, Aspergillus niger, Penicillium species, Candida albicans, Cryptococcus neoformans, Mucor species fungi. PMID:25298760
Lipowska, Malgorzata; Hayes, Brittany L.; Hansen, Lory; Taylor, Andrew; Marzilli, Luigi G.
1996-07-03
The compounds RNHC(=S)NH(CH(2))(n)()NHC(=S)NHR were prepared in a search for new, relatively small N(2)S(2) ligands. These dithiourea (DTU) ligands are the first chelates containing two potentially bidentate thiourea moieties. A one-step reaction of 1,3-diaminopropane (1) with aryl or alkyl isothiocyanates or of 1,2-diaminoethane (2) with phenyl isothiocyanate afforded the target ligands in excellent yields (95-98%). The Re(V)=O complexes of RNHC(=S)NH(CH(2))(3)NHC(=S)NHR ligands were obtained through ligand exchange reactions with Re(V) precursors. The chemistry required neither protection of the sulfur atoms for ligand synthesis nor deprotection prior to metal complexation. The structure of (1-phenyl-3-(3-phenylthioureido)propyl]thioureato)oxorhenium(V) (7a), determined by X-ray diffraction methods, revealed the expected pseudo-square-pyramidal geometry with an N(2)S(2) basal and an apical oxo donor set. Both coordinated N's (N(c)) were deprotonated. One uncoordinated N (N(u)) was deprotonated, producing a neutral complex containing an unexpected new type of dianionic, four-membered N,S chelate. In the crystal, the N(u) atoms, N(3)H and N(4), of one complex each formed an H-bond with N(4) and N(3)H, respectively, of a symmetry-related complex. The N(c)-C-S bond angles (106.1(6) and 101.5(6) degrees ) were severely distorted from the 120 degrees expected for an sp(2)-hybridized C. However, these small bite angles and the large N-Re-N bond angle (86.1(3) degrees ) allowed for the formation of two four-membered chelate rings with normal Re-N and Re-S bond distances. Attempts to prepare complexes with the PhNHC(=S)NH(CH(2))(2)NHC(=S)NHPh ligand were unsuccessful. These results suggest that a central five-membered chelate ring is too small to accommodate bidentate coordination of both thiourea moieties. NMR studies in methanol established that the neutral complex with one uncoordinated N deprotonated was the favored form in neutral and basic solutions. However, under acidic conditions, a cationic form with both uncoordinated N's protonated was favored.
Park, Sung Hyeon; Choi, Chang Hyuck; Lee, Seung Yong; Woo, Seong Ihl
2017-02-13
Combinatorial optical screening of aprotic electrocatalysts has not yet been achieved primarily due to H + -associated mechanisms of fluorophore modulation. We have overcome this problem by using fluorophore metal-organic complexes. In particular, eosin Y and quinine can be coordinated with various metallic cations (e.g., Li + , Na + , Mg 2+ , Zn 2+ , and Al 3+ ) in aprotic solvents, triggering changes in their fluorescent properties. These interactions have been used in a reliable screening method to determine oxygen reduction/evolution reaction activities of 100 Mn-based binary catalysts for the aprotic Li-air battery.
Dynamics of groups around interacting double ellipticals: Measuring dark matter haloes
NASA Technical Reports Server (NTRS)
Quintana, H.
1990-01-01
Binary galaxies, as binary stars, are important to measure masses, as suggested by Page (1952). Because three orbit parameters are measurable for galaxies at one instant of time, severe uncertainties remain in the orbit and mass determinations. These uncertainties can partly be overcome by statistical studies of selected samples and/or n-body simulations. Close double galaxies (and isolated galaxies) could also be useful to estimate dynamical masses if we can find test particles around them. Interacting elliptical pairs or dumb-bell galaxies are found with a large range, between 0-1200 km s(exp -1), of relative radial velocities. Standard 2-body orbit calculations, highly uncertain due to projection factors, suggest for the largest velocity differences very large galaxy masses, if the systems are bound and stationary. However, recent n-body simulations model these binaries as galaxies captured from hyperbolic orbits, requiring masses of order a few times 10(exp 11) solar maximum (Borne et al. 1988), but producing systems that are short lived. A different picture appears when we study observationally the dynamical mass of interacting double ellipticals using faint satellite galaxies. These satellites contribute little luminosity and, presumably, little mass to the system. The authors present results of two such groups, basically forming systems of test particles, around the dumb-bells NGC 4782/3 and IC 5049. They also briefly discuss the satellite group around the central dumb-bell in the cluster Sersic 40/6. Apparently, they detect large quantities of dark matter in the vicinity of these dumb-bell galaxies, because the system masses of approx. 4.5 times 10(exp 13) solar mass and 8 times 10(exp 13) solar mass for NGC 4782/3 and IC 5049, respectively, are quite high. Likewise, the mass of the Sersic 40/6 inner core is 7 times 10(exp 13) solar mass. The possibility that a common massive dark matter halo increases the merging times of these types of galaxies is suggested. Here, the authors assume H sub o = 100 km s (exp -1) Mpc(exp -1).
Cannibals in the thick disk: the young α-rich stars as evolved blue stragglers
NASA Astrophysics Data System (ADS)
Jofré, P.; Jorissen, A.; Van Eck, S.; Izzard, R. G.; Masseron, T.; Hawkins, K.; Gilmore, G.; Paladini, C.; Escorza, A.; Blanco-Cuaresma, S.; Manick, R.
2016-10-01
Spectro-seismic measurements of red giants enabled the recent discovery of stars in the thick disk that are more massive than 1.4 M⊙. While it has been claimed that most of these stars are younger than the rest of the typical thick disk stars, we show evidence that they might be products of mass transfer in binary evolution, notably evolved blue stragglers. We took new measurements of the radial velocities in a sample of 26 stars from APOKASC, including 13 "young" stars and 13 "old" stars with similar stellar parameters but with masses below 1.2 M⊙ and found that more of the young starsappear to be in binary systems with respect to the old stars.Furthermore, we show that the young stars do not follow the expected trend of [C/H] ratios versus mass for individual stars. However, with a population synthesis of low-mass stars including binary evolution and mass transfer, we can reproduce the observed [C/N] ratios versus mass. Our study shows how asteroseismology of solar-type red giants provides us with a unique opportunity to study the evolution of field blue stragglers after they have left the main-sequence.
HMB-45, S-100, NK1/C3, and MART-1 in metastatic melanoma.
Zubovits, Judit; Buzney, Elizabeth; Yu, Lawrence; Duncan, Lyn M
2004-02-01
The diagnosis of melanoma metastatic to lymph node remains a difficult problem given its histological diversity. We examined the staining patterns of S-100, NK1/C3, HMB-45, and MART-1 (DC10) in melanoma metastases to lymph nodes. Immunohistochemical stains were performed on tissue sections of 126 formalin-fixed lymph nodes from 126 patients with an established diagnosis of metastatic melanoma. A total of 98% of cases (123 of 126) stained positive for S-100, 93% (117 of 125) stained positive for NK1/C3, 82% (103 of 126) stained positive for MART-1, and 76% (95 of 125) stained positive for HMB-45. The distribution and intensity of staining varied among these markers. A diffuse staining pattern, defined as >50% of tumor cells stained, was observed in 83% of MART-1-positive cases but in only 56% of S-100-positive cases, 48% of NK1/C3-positive cases, and 34% of HMB-45-positive cases. A maximally intense signal was almost always observed for MART-1 (83% of positive cases) but was rarely observed for NK1/C3 (20%). S-100 and HMB-45 showed maximally intense staining in 50% and 54% of cases, respectively. S-100 and NK1/C3 stained both histiocytes and melanocytes, whereas MART-1 and HMB-45 stained only melanocytes. Seventy-eight cases (63%) stained positive for all 4 markers, 17 cases (14%) stained for all markers except HMB-45, 13 cases (10%) stained for all markers except MART-1, 6 cases (5%) stained only with S-100 and NK1/C3, 4 cases (3%) stained only with S-100 and HMB-45, and 2 cases stained for all markers except S-100. One case each stained for the following: only S-100, only S-100 and HMB-45, and all markers except NK1/C3. One case exhibited absence of staining for any of these markers. We demonstrate that lymph node metastases of melanoma are heterogeneous with regard to tumor marker expression. S-100 and NK1/C3 were the most sensitive stains for detecting metastatic melanoma; however, they both also stain other nontumor cells in lymph nodes. MART-1 did not stain histiocytes and exhibited a more frequently intense and diffuse staining pattern than NK1/C3. HMB-45 was less sensitive and demonstrated less diffuse staining than MART-1.
Fabrication of (Ba,K)Fe2As2 tapes by ex situ PIT process using Ag-Sn alloy single sheath
NASA Astrophysics Data System (ADS)
Togano, K.; Gao, Z.; Matsumoto, A.; Kikuchi, A.; Kumakura, H.
2017-01-01
Instead of ordinal pure Ag, Ag-based Sn binary alloys (up to 7.5 at%Sn) with higher mechanical strength are used for the sheath material of ex situ powder-in-tube (PIT)-processed (Ba,K)Fe2As2(Ba-122) tapes. We found that the use of the Ag-Sn alloy enhances the densification and texturing of the Ba-122 core, resulting in higher transport, J c. Moreover, the optimum heat treatment temperature for a high J c can be lowered by around 100 °C due to the higher packing density of the Ba-122 core prior to the final heat treatment. We also found that the smoothness of the interface between the sheath and Ba-122 core is significantly improved by using the Ag-Sn binary alloy sheaths. These results show that the Ag-Sn alloy is promising as a sheath material in PIT-processed Ba-122 superconducting wires.
Implementation of a Zilog Z-80 Base Realization Library for the Computer Systems Design Environment.
1984-03-01
o the At I nMional Symposi u!9 on r -2r RLm-9rjatign LiongUigea, IEEE Computer Society, October 8, 1979 . 1S. Rome Air Development Center RADc-TR-79-6...a On CS * r . 13 Lolw a 6-0 A A0 C 0 4-SSao~t 0 0 1 -- ;*U a 4. . 1 0- a C1 C 6. 04 L 6 0 OUS U- r G OO C rC 100- ONC40 -Wo 0060- i 40C 1 .0*6 U lh0...aa > >oIL O > 0 Uf~0-~IU4’ EL 6. . V 6.L2 CC~ 000’U~66 A CL v 11 13 a a oi co ’D 4 1. u r . c O U I 6 -f 21 06U a4’L3 cl c 4 . - c a 1 0 U 62 6 0. 11
The 12C/13C Ratio in Sgr B2(N): Constraints for Galactic Chemical Evolution and Isotopic Chemistry
NASA Astrophysics Data System (ADS)
Halfen, D. T.; Woolf, N. J.; Ziurys, L. M.
2017-08-01
A study has been conducted of 12C/13C ratios in five complex molecules in the Galactic center. H2CS, CH3CCH, NH2CHO, CH2CHCN, and CH3CH2CN and their 13C-substituted species have been observed in numerous transitions at 1, 2, and 3 mm, acquired in a spectral-line survey of Sgr B2(N), conducted with the telescopes of the Arizona Radio Observatory (ARO). Between 22 and 54 individual, unblended lines for the 12C species and 2-54 for 13C-substituted analogs were modeled in a global radiative transfer analysis. All five molecules were found to consistently exhibit two velocity components near V LSR ˜ 64 and 73 km s-1, with column densities ranging from N tot ˜ 3 × 1014 - 4 × 1017 cm-2 and ˜2 × 1013 - 1 × 1017 cm-2 for the 12C and 13C species, respectively. Based on 14 different isotopic combinations, ratios were obtained in the range 12C/13C = 15 ± 5 to 33 ± 13, with an average value of 24 ± 7, based on comparison of column densities. These measurements better anchor the 12C/13C ratio at the Galactic center, and suggest a slightly revised isotope gradient of 12C/13C = 5.21(0.52) D GC + 22.6(3.3). As indicated by the column densities, no preferential 13C enrichment was found on the differing carbon sites of CH3CCH, CH2CHCN, and CH3CH2CN. Because of the elevated temperatures in Sgr B2(N), 13C isotopic substitution is effectively “scrambled,” diminishing chemical fractionation effects. The resulting ratios thus reflect stellar nucleosynthesis and Galactic chemical evolution, as is likely the case for most warm clouds.
Synthesis of chiral chloroquine and its analogues as antimalarial agents.
Sinha, Manish; Dola, Vasanth R; Soni, Awakash; Agarwal, Pooja; Srivastava, Kumkum; Haq, Wahajul; Puri, Sunil K; Katti, Seturam B
2014-11-01
In this investigation, we describe a new approach to chiral synthesis of chloroquine and its analogues. All tested compounds displayed potent activity against chloroquine sensitive as well as chloroquine resistant strains of Plasmodium falciparum in vitro and Plasmodium yoelii in vivo. Compounds S-13 b, S-13c, S-13 d and S-13 i displayed excellent in vitro antimalarial activity with an IC50 value of 56.82, 60.41, 21.82 and 7.94 nM, respectively, in the case of resistant strain. Furthermore, compounds S-13a, S-13c and S-13 d showed in vivo suppression of 100% parasitaemia on day 4 in the mouse model against Plasmodium yoelii when administered orally. These results underscore the application of synthetic methodology and need for further lead optimization. Copyright © 2014 Elsevier Ltd. All rights reserved.
An optimized 13C-urea breath test for the diagnosis of H pylori infection
Campuzano-Maya, Germán
2007-01-01
AIM: To validate an optimized 13C-urea breath test (13C-UBT) protocol for the diagnosis of H pylori infection that is cost-efficient and maintains excellent diagnostic accuracy. METHODS: 70 healthy volunteers were tested with two simplified 13C-UBT protocols, with test meal (Protocol 2) and without test meal (Protocol 1). Breath samples were collected at 10, 20 and 30 min after ingestion of 50 mg 13C-urea dissolved in 10 mL of water, taken as a single swallow, followed by 200 mL of water (pH 6.0) and a circular motion around the waistline to homogenize the urea solution. Performance of both protocols was analyzed at various cut-off values. Results were validated against the European protocol. RESULTS: According to the reference protocol, 65.7% individuals were positive for H pylori infection and 34.3% were negative. There were no significant differences in the ability of both protocols to correctly identify positive and negative H pylori individuals. However, only Protocol 1 with no test meal achieved accuracy, sensitivity, specificity, positive and negative predictive values of 100%. The highest values achieved by Protocol 2 were 98.57%, 97.83%, 100%, 100% and 100%, respectively. CONCLUSION: A 10 min, 50 mg 13C-UBT with no test meal using a cut-off value of 2-2.5 is a highly accurate test for the diagnosis of H pylori infection at a reduced cost. PMID:17907288
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Michael C.; Dupuy, Trent J.; Leggett, S. K., E-mail: mliu@ifa.hawaii.ed
Highly unequal-mass ratio binaries are rare among field brown dwarfs, with the mass ratio distribution of the known census described by q {sup (4.9{+-}0.7)}. However, such systems enable a unique test of the joint accuracy of evolutionary and atmospheric models, under the constraint of coevality for the individual components (the 'isochrone test'). We carry out this test using two of the most extreme field substellar binaries currently known, the T1 + T6 {epsilon} Ind Bab binary and a newly discovered 0.''14 T2.0 + T7.5 binary, 2MASS J12095613-1004008AB, identified with Keck laser guide star adaptive optics. The latter is the mostmore » extreme tight binary resolved to date (q {approx} 0.5). Based on the locations of the binary components on the Hertzsprung-Russell (H-R) diagram, current models successfully indicate that these two systems are coeval, with internal age differences of log(age) = -0.8 {+-} 1.3(-1.0{sup +1.2}{sub -1.3}) dex and 0.5{sup +0.4}{sub -0.3}(0.3{sup +0.3}{sub -0.4}) dex for 2MASS J1209-1004AB and {epsilon} Ind Bab, respectively, as inferred from the Lyon (Tucson) models. However, the total mass of {epsilon} Ind Bab derived from the H-R diagram ({approx} 80 M{sub Jup} using the Lyon models) is strongly discrepant with the reported dynamical mass. This problem, which is independent of the assumed age of the {epsilon} Ind Bab system, can be explained by a {approx} 50-100 K systematic error in the model atmosphere fitting, indicating slightly warmer temperatures for both components; bringing the mass determinations from the H-R diagram and the visual orbit into consistency leads to an inferred age of {approx} 6 Gyr for {epsilon} Ind Bab, older than previously assumed. Overall, the two T dwarf binaries studied here, along with recent results from T dwarfs in age and mass benchmark systems, yield evidence for small ({approx}100 K) errors in the evolutionary models and/or model atmospheres, but not significantly larger. Future parallax, resolved spectroscopy, and dynamical mass measurements for 2MASS J1209-1004AB will enable a more stringent application of the isochrone test. Finally, the binary nature of this object reduces its utility as the primary T3 near-IR spectral typing standard; we suggest SDSS J1206+2813 as a replacement.« less
Lead(II) Binding to the Chelating Agent d-Penicillamine in Aqueous Solution
2015-01-01
A spectroscopic investigation of the complexes formed between the Pb(II) ion and d-penicillamine (H2Pen), a chelating agent used in the treatment of lead poisoning, was carried out on two sets of alkaline aqueous solutions with CPb(II) ≈ 10 and 100 mM, varying the H2Pen/Pb(II) molar ratio (2.0, 3.0, 4.0, 10.0). Ultraviolet–visible (UV-vis) spectra of the 10 mM Pb(II) solutions consistently showed an absorption peak at 298 nm for S– → Pb(II) ligand-to-metal charge-transfer. The downfield 13C NMR chemical shift for the penicillamine COO– group confirmed Pb(II) coordination. The 207Pb NMR chemical shifts were confined to a narrow range between 1806 ppm and 1873 ppm for all Pb(II)-penicillamine solutions, indicating only small variations in the speciation, even in large penicillamine excess. Those chemical shifts are considerably deshielded, relative to the solid-state 207Pb NMR isotropic chemical shift of 909 ppm obtained for crystalline penicillaminatolead(II) with Pb(S,N,O-Pen) coordination. The Pb LIII-edge extended X-ray absorption fine structure (EXAFS) spectra obtained for these solutions were well-modeled with two Pb–S and two Pb-(N/O) bonds with mean distances 2.64 ± 0.04 Å and 2.45 ± 0.04 Å, respectively. The combined spectroscopic results, reporting δ(207Pb) ≈ 1870 ppm and λmax ≈ 298 nm for a PbIIS2NO site, are consistent with a dominating 1:2 lead(II):penicillamine complex with [Pb(S,N,O-Pen)(S-HnPen)]2–n (n = 0–1) coordination in alkaline solutions, and provide useful structural information on how penicillamine can function as an antidote against lead toxicity in vivo. PMID:25385465
Simulating Gravitational Radiation from Binary Black Holes Mergers as LISA Sources
NASA Technical Reports Server (NTRS)
Baker, John
2005-01-01
A viewgraph presentation on the simulation of gravitational waves from Binary Massive Black Holes with LISA observations is shown. The topics include: 1) Massive Black Holes (MBHs); 2) MBH Binaries; 3) Gravitational Wavws from MBH Binaries; 4) Observing with LISA; 5) How LISA sees MBH binary mergers; 6) MBH binary inspirals to LISA; 7) Numerical Relativity Simulations; 8) Numerical Relativity Challenges; 9) Recent Successes; 10) Goddard Team; 11) Binary Black Hole Simulations at Goddard; 12) Goddard Recent Advances; 13) Baker, et al.:GSFC; 13) Starting Farther Out; 14) Comparing Initial Separation; 15) Now with AMR; and 16) Conclusion.
Turbidity of a Binary Fluid Mixture: Determining Eta
NASA Technical Reports Server (NTRS)
Jacobs, Donald T.
1996-01-01
A ground based (1-g) experiment is in progress that will measure the turbidity of a density-matched, binary fluid mixture extremely close to its liquid-liquid critical point. By covering the range of reduced temperatures t equivalent to (T-T(sub c)) / T(sub c) from 10(exp -8) to 10(exp -2), the turbidity measurements will allow the critical exponent eta to be determined. No experiment has precisely determined a value of the critical exponent eta, yet its value is significant to theorists in critical phenomena. Relatively simple critical phenomena, as in the liquid-liquid system studied here, serve as model systems for more complex systems near a critical point.
Brodaczewska, Natalia; Košťálová, Zuzana; Uhrín, Dušan
2018-02-01
Overlap of NMR signals is the major cause of difficulties associated with NMR structure elucidation of molecules contained in complex mixtures. A 2D homonuclear correlation spectroscopy in particular suffers from low dispersion of 1 H chemical shifts; larger dispersion of 13 C chemical shifts is often used to reduce this overlap, while still providing the proton-proton correlation information e.g. in the form of a 2D 1 H, 13 C HSQC-TOCSY experiment. For this methodology to work, 13 C chemical shift must be resolved. In case of 13 C chemical shifts overlap, 1 H chemical shifts can be used to achieve the desired resolution. The proposed (3, 2)D 1 H, 13 C BIRD r,X -HSQC-TOCSY experiment achieves this while preserving singlet character of cross peaks in the F 1 dimension. The required high-resolution in the 13 C dimension is thus retained, while the cross peak overlap occurring in a regular HSQC-TOCSY experiment is eliminated. The method is illustrated on the analysis of a complex carbohydrate mixture obtained by depolymerisation of a fucosylated chondroitin sulfate isolated from the body wall of the sea cucumber Holothuria forskali.
Oxidation Kinetics of a NiPtTi High Temperature Shape Memory Alloy
NASA Technical Reports Server (NTRS)
Smialek, James L.; Humphrey, Donald L.; Noebe, Ronald D.
2007-01-01
A high temperature shape memory alloy (HTSMA), Ni30Pt50Ti, with an M(sub s) near 600 C, was isothermally oxidized in air for 100 hr over the temperature range of 500 to 900 C. Parabolic kinetics were confirmed by log-log and parabolic plots and showed no indication of fast transient oxidation. The overall behavior could be best described by the Arrhenius relationship: k(sub p) = 1.64 x 10(exp 12)[(-250 kJ/mole)/RT] mg(sup 2)/cm(sup 4)hr. This is about a factor of 4 reduction compared to values measured here for a binary Ni47Ti commercial SMA. The activation energy agreed with most literature values for TiO2 scale growth measured for elemental Ti and other NiTi alloys. Assuming uniform alloy depletion of a 20 mil (0.5 mm) dia. HTSMA wire, approx. 1 percent Ti reduction is predicted after 20,000 hr oxidation at 500 C, but becomes much more serious at higher temperatures.
Lowe, D J; Eady, R R; Thorneley, N F
1978-01-01
Klebsiella pneumoniae nitrogenase exhibited four new electron-paramagnetic-resonance signals during turnover at 10 degrees C, pH7.4, which were assigned to intermediates present in low concentrations in the steady state. 57Fe-substituted Mo--Fe protein showed that they arose from Fe--S clusters in the Mo--Fe protein of nitrogenase. The new signals are designated: Ic, g values at 4.67, 3.37 and approx. 2.0; VI, g values at 2.125, 2.000 and 2.000; VII, g values at 5.7 and 5.4; VIII, g values at 2.092, 1.974 and 1.933. The sharp axial signal VI arises from a Fe4S4 cluster at the --1 oxidation level. This signal was only detected in the presence of ethylene and provides the first evidence of an enzyme--product complex for nitrogenase. [13C]Acetylene and [13C]ethylene provided no evidence for direct binding of this substrate and product to the Fe--S clusters giving rise to these signals. The dependence of signal intensities on acetylene concentration indicated two types of binding site, with apparent dissociation constants K less than 16 micron and K approximately 13mM. A single binding site for ethylene (K=1.5mM) was detected. A scheme is proposed for the mechanism of reduction of acetylene to ethylene and inhibition of this reaction by CO. PMID:210766
Rhenals, Maricela Viola; Strasberg-Rieber, Mary; Rieber, Manuel
2010-02-25
In contrast to other metal-dithiocarbamate [DEDTC] complexes, the copper-DEDTC complex is highly cytotoxic, inducing oxidative stress, preferentially in tumor cells. Because nitric oxide (NO) forms adducts with Cu[DEDTC](2), we investigated whether NO donors like S-nitroso-N-acetyl penicillamine (SNAP) or sodium nitroprusside (SNP), and nitrite, a NO decomposition product, modulate Cu[DEDTC](2) cytotoxicity against human tumor cells. We show that apoptosis-associated PARP cleavage and inducible nitric oxide synthase (iNOS) down-regulation induced by nanomolar Cu[DEDTC](2), are counteracted by 50 muM SNAP, SNP, or CoCl(2), an inducer of hypoxia and NO signaling. Nitrite was stochiometrically effective in antagonizing Cu[DEDTC](2) cytotoxicity and inducing shifts in the absorption spectrum of the binary complex in the 280 and 450 nm regions. Subtoxic concentrations of Cu[DEDTC](2) became lethal when tumor cells were pretreated with c-PTIO, a membrane-impermeable scavenger for extracellular NO. Our results suggest that: (a) reactive oxygen species induced by Cu[DEDTC](2) are scavenged by nitrite released from NO, (b) the extent of lethality of Cu[DEDTC](2) is dependent on the reciprocal formation of an inactive ternary Cu[DEDTC](2)NO copper-nitrosyl complex.
Single-Pulse Dual-Energy Mammography Using a Binary Screen Coupled to Dual CCD Cameras
1999-08-01
Fossum, "Active pixel sensors—Are CCD’s Dinosaurs ?," Proc. SPIE 1900, 2-14 (1993). "S. Mendis, S. E. Kemeny, R. Gee, B. Pain, and E. R. Fossum, "Progress...Clin Oncol 13:1470-1477, 1995 12. Wahl RL, Zasadny K, Helvie M, et al: Metabolic monitoring of breast cancer chemohormonotherapy using posi- tron
NASA Astrophysics Data System (ADS)
Singh, Ajay K.; Pandey, O. P.; Sengupta, S. K.
2013-09-01
Zn(II) complexes have been synthesized by reacting zinc acetate with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/benzaldehyde/indoline-2,3-dione. All these complexes are soluble in DMF and DMSO; low molar conductance values indicate that they are non electrolytes. Elemental analyses suggest that the complexes have 1:2 metal to ligands stoichiometry of the types [ZnL2(H2O)2](L = monoanionic Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/indoline-2,3-dione) [ZnL2‧(OOCCH3)2(H2O)2](L‧ = neutral Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde), and they were characterized by IR, 1H NMR, and 13C NMR. Particle sizes of synthesized compounds were measured with dynamic light scattering (DLS) analyser which indicates that particle diameter are of the range ca. 100-200 nm. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and antifungal activities (Colletotrichum falcatum (C. falcatum), Aspergillus niger (A. niger), Fusarium oxysporium (F. oxysporium) Curvularia pallescence (C. pallescence). The antimicrobial activities have shown that upon complexation the activity increases.
Spectral properties of binary asteroids
NASA Astrophysics Data System (ADS)
Pajuelo, Myriam; Birlan, Mirel; Carry, Benoît; DeMeo, Francesca E.; Binzel, Richard P.; Berthier, Jérôme
2018-07-01
We present the first attempt to characterize the distribution of taxonomic class among the population of binary asteroids (15 per cent of all small asteroids). For that, an analysis of 0.8-2.5 µm near-infrared spectra obtained with the SpeX instrument on the NASA/IRTF (Infrared Telescope Facility) is presented. Taxonomic class and meteorite analogue is determined for each target, increasing the sample of binary asteroids with known taxonomy by 21 per cent. Most binary systems are bound in the S, X, and C classes, followed by Q and V types. The rate of binary systems in each taxonomic class agrees within uncertainty with the background population of small near-Earth objects and inner main belt asteroids, but for the C types which are under-represented among binaries.
Podgórska, Marta; Ołdak, Monika; Marthaler, Anna; Fingerle, Alina; Walch-Rückheim, Barbara; Lohse, Stefan; Müller, Cornelia S L; Vogt, Thomas; Ustav, Mart; Wnorowski, Artur; Malejczyk, Magdalena; Majewski, Sławomir; Smola, Sigrun
2018-01-01
Persistent genus β-HPV (human papillomavirus) infection is a major co-factor for non-melanoma skin cancer in patients suffering from the inherited skin disease epidermodysplasia verruciformis (EV). Malignant EV lesions are particularly associated with HPV type 5 or 8. There is clinical and molecular evidence that HPV8 actively suppresses epithelial immunosurveillance by interfering with the recruitment of Langerhans cells, which may favor viral persistence. Mechanisms how persistent HPV8 infection promotes the carcinogenic process are, however, less well understood. In various tumor types chronic inflammation has a central role in tumor progression. The calprotectin complex consisting of S100A8 and S100A9 proteins has recently been identified as key driver of chronic and tumor promoting inflammation in skin carcinogenesis. It induces chemotaxis of neutrophil granulocytes and modulates inflammatory as well as immune responses. In this study, we demonstrate that skin lesions of EV-patients are massively infiltrated by inflammatory cells, including CD15 + granulocytes. At the same time we observed a very strong expression of S100A8 and S100A9 proteins in lesional keratinocytes, which was mostly confined to the suprabasal layers of the epidermis. Both proteins were hardly detected in non-lesional skin. Further experiments revealed that the HPV8 oncoproteins E6 and E7 were not involved in S100A8/A9 up-regulation. They rather suppressed differentiation-induced S100A8/A9 expression. In contrast, the viral transcription factor E2 strongly enhanced PMA-mediated S100A8/A9 up-regulation in primary human keratinocytes. Similarly, a tremendous up-regulation of both S100 proteins was observed, when minute amounts of the PMA-inducible CCAAT/enhancer binding protein β (C/EBPβ), which is expressed at low levels in the suprabasal layers of the epidermis, were co-expressed together with HPV8 E2. This confirmed our previous observation that C/EBPβ interacts and functionally synergizes with the HPV8 E2 protein in differentiation-dependent gene expression. Potent synergistic up-regulation of S100A8/A9 was seen at transcriptional and protein levels. S100A8/A9 containing supernatants from keratinocytes co-expressing HPV8 E2 and C/EBPβ significantly induced chemotaxis of granulocytes in migration assays supporting the relevance of our finding. In conclusion, our data suggest that the HPV8 E2 protein actively contributes to the recruitment of myeloid cells into EV skin lesions, which may support chronic inflammation and progression to skin cancer.
Crystal structure of bis-(3-bromo-pyridine-κN)bis-(O-ethyl di-thio-carbonato-κ(2) S,S')nickel(II).
Kant, Rajni; Kour, Gurvinder; Anthal, Sumati; Neerupama; Sachar, Renu
2015-01-01
In the title mol-ecular complex, [Ni(C3H5OS2)2(C5H4BrN)2], the Ni(2+) cation is located on a centre of inversion and has a distorted octa-hedral N2S4 environment defined by two chelating xanthate ligands and two monodentate pyridine ligands. The C-S bond lengths of the thio-carboxyl-ate group are indicative of a delocalized bond and the O-Csp (2) bond is considerably shorter than the O-Csp (3) bond, consistent with a significant contribution of one resonance form of the xanthate anion that features a formal C=O+ unit and a negative charge on each of the S atoms. The packing of the mol-ecules is stabilized by C-H⋯S and C-H⋯π inter-actions. In addition, π-π inter-actions between the pyridine rings [centroid-to-centroid distance = 3.797 (3) Å] are also present. In the crystal structure, mol-ecules are arranged in rows along [100], forming layers parallel to (010) and (001).
NASA Astrophysics Data System (ADS)
Tian, Laijin; Yao, Yanze; Wang, Yuhua; Liu, Jin
2018-03-01
Six new diorganotin N-[(5-chloro-2-oxyphenyl)methylene]valinates, R2SnL (R = Me, 1; Et, 2; L = 5-Cl-2-OC6H3CH = NCH(i-Pr)COO: (S)-, a; (R)-, b; (RS)-, c), have been synthesized from the reaction of R2SnCl2 with the chiral ligand KHL (potassium salt of HL) in different solvents and characterized by elemental analysis, IR, NMR (1H, 13C and 119Sn) spectra. In benzene, the configuration of the chiral ligand was retained. (S)-Enantiomers (1a and 2a) and (R)-enantiomers (1b and 2b) display discrete molecular structures with distorted trigonal bipyramidal geometries in which two C atoms of organic groups (R) and the imino N atom occupy the equatorial positions and a phenoxide O and an unidentate carboxylate group O atom are in the axial orientation. In the methanol, the chiral ligand was racemized. 1cṡMeOH is a centrosymmetric dimers formed by (R)- and (S)- enantiomers through two Snsbnd OṡṡṡSn bridges. The coordination geometry of the Sn atom can be described as a distorted pentagonal bipyramid with two methyl groups in axial positions. The crystal of 2c is composed of two threefold symmetric trimers, a [Et2SnL-(R)]3 and a [Et2SnL-(S)]3, with a macrocyclic 12-membered ring structure formed by the bidenate bridging coordination of carboxylate group to tin atoms. Each tin atom is six-coordinated in distorted [SnC2NO3] octahedron geometry. The fluorescence properties of ligand KHL and complexes 1 (1a-1c) and 2 (2a-2c) have been measured. The results show the complexes may be explored for potential luminescent materials.
Chemistry of a newly detected circumbinary disk in Ophiuchus
NASA Astrophysics Data System (ADS)
Artur de la Villarmois, Elizabeth; Kristensen, Lars E.; Jørgensen, Jes K.; Bergin, Edwin A.; Brinch, Christian; Frimann, Søren; Harsono, Daniel; Sakai, Nami; Yamamoto, Satoshi
2018-06-01
Context. Astronomers recently started discovering exoplanets around binary systems. Therefore, understanding the formation and evolution of circumbinary disks and their environment is crucial for a complete scenario of planet formation. Aims: The purpose of this paper is to present the detection of a circumbinary disk around the system Oph-IRS67 and analyse its chemical and physical structure. Methods: We present high-angular-resolution (0.''4, 60 AU) observations of C17O, H13CO+, C34S, SO2, C2H and c-C3H2 molecular transitions with the Atacama Large Millimeter/submillimeter Array (ALMA) at wavelengths of 0.8 mm. The spectrally and spatially resolved maps reveal the kinematics of the circumbinary disk as well as its chemistry. Molecular abundances are estimated using the non-local thermodynamic equilibrium (LTE) radiative-transfer tool RADEX. Results: The continuum emission agrees with the position of Oph-IRS67 A and B, and reveals the presence of a circumbinary disk around the two sources. The circumbinary disk has a diameter of 620 AU and is well traced by C17O and H13CO+ emission. Two further molecular species, C2H and c-C3H2, trace a higher-density region which is spatially offset from the sources ( 430 AU). Finally, SO2 shows compact and broad emission around only one of the sources, Oph-IRS67 B. The molecular transitions which trace the circumbinary disk are consistent with a Keplerian profile on smaller disk scales (≲200 AU) and an infalling profile for larger envelope scales (≳200 AU). The Keplerian fit leads to an enclosed mass of 2.2 M⊙. Inferred CO abundances with respect to H2 are comparable to the canonical ISM value of 2.7 × 10-4, reflecting that freeze-out of CO in the disk midplane is not significant. Conclusions: Molecular emission and kinematic studies prove the existence and first detection of the circumbinary disk associated with the system Oph-IRS67. The high-density region shows a different chemistry than the disk, being enriched in carbon chain molecules. The lack of methanol emission agrees with the scenario where the extended disk dominates the mass budget in the innermost regions of the protostellar envelope, generating a flat density profile where less material is exposed to high temperatures, and thus, complex organic molecules would be associated with lower column densities. Finally, Oph-IRS67 is a promising candidate for proper motion studies and the detection of both circumstellar disks with higher-angular-resolution observations.
Al-Jaroudi, Said S; Monim-ul-Mehboob, M; Altaf, Muhammad; Al-Saadi, Abdulaziz A; Wazeer, Mohammed I M; Altuwaijri, Saleh; Isab, Anvarhusein A
2014-12-01
The gold(III) complexes of the type [(DACH)Au(en)]Cl3, 1,2-Diaminocyclohexane ethylenediamine gold(III) chloride [where 1,2-DACH = cis-, trans-1,2- and S,S-1,2diaminocyclohexane and en = ethylenediamine] have been synthesized and characterized using various analytical and spectroscopic techniques including elemental analysis, UV-Vis and FTIR spectra; and solution as well as solid-state NMR measurements. The solid-state (13)C NMR shows that 1,2-diaminocyclohexane (1,2-DACH) and ethylenediamine (en) are strongly bound to the gold(III) center via N donor atoms. The stability of the mixed diamine ligand gold(III) was determined by (1)H and (13)C NMR spectra. Their electrochemical behavior was studied by cyclic voltammetry. The structural details and relative stabilities of the four possible isomers of the complexes were also reported at the B3LYP/LANL2DZ level of theory. The coordination sphere of these complexes around gold(III) center adopts distorted square planar geometry. The computational study also demonstrates that trans- conformations is slightly more stable than the cis-conformations. The antiproliferative effects and cytotoxic properties of the mixed diamine ligand gold(III) complexes were evaluated in vitro on human gastric SGC7901 and prostate PC3 cancer cells using MTT assay. The antiproliferative study of the gold(III) complexes on PC3 and SGC7901 cells indicate that complex 1 is the most effective antiproliferative agent among mixed ligand based gold(III) complexes 1-3. The IC50 data reveal that the in vitro cytotoxicity of complexes 1 and 3 against SGC7901 cancer cells are fairly better than that of cisplatin.
Elucidating the structure and function of S100 proteins in membranes
NASA Astrophysics Data System (ADS)
Valenzuela, Stella M.; Berkahn, Mark; Martin, Donald K.; Huynh, Thuan; Yang, Zheng; Geczy, Carolyn L.
2006-01-01
S100 proteins are important Ca 2+-binding proteins involved in vital cellular functions including the modulation of cell growth, migration and differentiation, regulation of intracellular signal transduction/phosphorylation pathways, energy metabolism, cytoskeletal interactions and modulation of ion channels. Furthermore, they are implicated in oncogenesis and numerous other disease states. Three S100 proteins: S100A8, S100A9 and S100A12 are constitutively expressed in neutrophils and monocytes. At low levels of intracellular Ca 2+, S100A8 and S100A9 are located predominantly in the cytosol but when Ca 2+ concentrations are elevated as a consequence of activation, they translocate to membranes and complex with cytoskeletal components such as vimentin. The functions of S100A8 and S100A9 at the plasma membrane remain unclear. A possible role may be the regulation of ion channel proteins. The current study uses the techniques of Atomic Force Microscopy and production of artificial lipid membranes in the form of liposomes to investigate possible mechanisms for the insertion of these proteins into membranes in order to elucidate their structure and stoichiometry in the transmembrane state. We have successfully imaged the liposomes as a lipid bilayer, the S100A8/A9 protein complex in solution and the S100A8/A9 complex associating with lipid, using tapping-mode atomic force microscopy, in buffer.
Rudrangi, Shashi Ravi Suman; Kaialy, Waseem; Ghori, Muhammad U; Trivedi, Vivek; Snowden, Martin J; Alexander, Bruce David
2016-07-01
The aim of this study was to enhance the apparent solubility and dissolution properties of flurbiprofen through inclusion complexation with cyclodextrins. Especially, the efficacy of supercritical fluid technology as a preparative technique for the preparation of flurbiprofen-methyl-β-cyclodextrin inclusion complexes was evaluated. The complexes were prepared by supercritical carbon dioxide processing and were evaluated by solubility, differential scanning calorimetry, X-ray powder diffraction, scanning electron microscopy, practical yield, drug content estimation and in vitro dissolution studies. Computational molecular docking studies were conducted to study the possibility of molecular arrangement of inclusion complexes between flurbiprofen and methyl-β-cyclodextrin. The studies support the formation of stable molecular inclusion complexes between the drug and cyclodextrin in a 1:1 stoichiometry. In vitro dissolution studies showed that the dissolution properties of flurbiprofen were significantly enhanced by the binary mixtures prepared by supercritical carbon dioxide processing. The amount of flurbiprofen dissolved into solution alone was very low with 1.11±0.09% dissolving at the end of 60min, while the binary mixtures processed by supercritical carbon dioxide at 45°C and 200bar released 99.39±2.34% of the drug at the end of 30min. All the binary mixtures processed by supercritical carbon dioxide at 45°C exhibited a drug release of more than 80% within the first 10min irrespective of the pressure employed. The study demonstrated the single step, organic solvent-free supercritical carbon dioxide process as a promising approach for the preparation of inclusion complexes between flurbiprofen and methyl-β-cyclodextrin in solid-state. Copyright © 2016 Elsevier B.V. All rights reserved.
Cerný, Radovan; Renaudin, Guillaume; Favre-Nicolin, Vincent; Hlukhyy, Viktor; Pöttgen, Rainer
2004-06-01
The new binary compound Mg(1 + x)Ir(1 - x) (x = 0-0.054) was prepared by melting the elements in the Mg:Ir ratio 2:3 in a sealed tantalum tube under an argon atmosphere in an induction furnace (single crystals) or by annealing cold-pressed pellets of the starting composition Mg:Ir 1:1 in an autoclave under an argon atmosphere (powder sample). The structure was independently solved from high-resolution synchrotron powder and single-crystal X-ray data: Pearson symbol oC304, space group Cmca, lattice parameters from synchrotron powder data a = 18.46948 (6), b = 16.17450 (5), c = 16.82131 (5) A. Mg(1 + x)Ir(1 - x) is a topologically close-packed phase, containing 13 Ir and 12 Mg atoms in the asymmetric unit, and has a narrow homogeneity range. Nearly all the atoms have Frank-Kasper-related coordination polyhedra, with the exception of two Ir atoms, and this compound contains the shortest Ir-Ir distances ever observed. The solution of a rather complex crystal structure from powder diffraction, which was fully confirmed by the single-crystal method, shows the power of powder diffraction in combination with the high-resolution data and the global optimization method.
Molecular dynamics study of polysaccharides in binary solvent mixtures of an ionic liquid and water.
Liu, Hanbin; Sale, Kenneth L; Simmons, Blake A; Singh, Seema
2011-09-01
Some ionic liquids (ILs) have great promise as effective solvents for biomass pretreatment, and there are several that have been reported that can dissolve large amounts of cellulose. The solubilized cellulose can then be recovered by addition of antisolvents, such as water or ethanol, and this regeneration process plays an important role in the subsequent enzymatic saccharification reactions and in the recovery of the ionic liquid. To date, little is known about the fundamental intermolecular interactions that drive the dissolution and subsequent regeneration of cellulose in complex mixtures of ionic liquids, water, and cellulose. To investigate these interactions, in this work, molecular dynamics (MD) simulations were carried out to study binary and ternary mixtures of the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) with water and a cellulose oligomer. Simulations of a cellulose oligomer dissolved in three concentrations of binary mixtures of [C2mim][OAc] and water were used to represent the ternary system in the dissolution phase (high [C2mim][OAc] concentration) and present during the initial phase of the regeneration step (intermediate and low [C2mim][OAc] concentrations). The MD analysis of the structure and dynamics that exist in these binary and ternary mixtures provides information on the key intermolecular interactions between cellulose and [C2mim][OAc] that lead to dissolution of cellulose and the key intermolecular interactions in the intermediate states of cellulose precipitation as a function of water content in the cellulose/IL/water system. The analysis of this intermediate state provides new insight into the molecular driving forces present in this ternary system. © 2011 American Chemical Society
Synthesis and structure of the first discrete dinuclear cationic aluminum complexes.
Wang, Xingbao; Dorcet, Vincent; Luo, Yi; Carpentier, Jean-Francois; Kirillov, Evgueni
2016-08-02
The reactions of the charge neutral dinuclear aluminum tetraalkyl complexes of di-Schiff base ligands, i.e. [AlMe2{ON}-R-{ON}AlMe2] (1a, R = 1,3-propylene; 1b, R = 1,3-cyclohexylene) with B(C6F5)3 and [H(Et2O)2](+)[H2N{B(C6F5)3}2](-) were investigated. When B(C6F5)3 was used as the cationizing agent (1 or 2 equiv. vs. Al), only monocationic dinuclear complexes [2a,b]+[MeB(C6F5)3]- were obtained. In contrast, with [H(Et2O)2](+)[H2N{B(C6F5)3}2](-), both mixed-dicationic [3a,b·(OEt2)2]2+[MeB(C6F5)3]-[H2N{B(C6F5)3}2]- and homo-dicationic [3a,b·(OEt2)2]2+[H2N{B(C6F5)3}2]-2 ion-pairs were prepared. All cationic complexes were characterized by (1)H, (13)C, (19)F and (11)B NMR spectroscopy, and an X-ray diffraction study was performed for [3b·(OEt2)2]2+[H2N{B(C6F5)3}2]-2.
Kelly, Rory P.; Falcone, Marta; Lamsfus, Carlos Alvarez; Scopelliti, Rosario; Maron, Laurent; Meyer, Karsten
2017-01-01
Herein, we report the synthesis and characterisation of the first terminal uranium(v) sulfide and a related UV trithiocarbonate complex supported by sterically demanding tris(tert-butoxy)siloxide ligands. The reaction of the potassium-bound UV imido complex, [U(NAd){OSi(OtBu)3}4K] (4), with CS2 led to the isolation of perthiodicarbonate [K(18c6)]2[C2S6] (6), with concomitant formation of the UIV complex, [U{OSi(OtBu)3}4], and S 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 CNAd. In contrast, the reaction of the UV imido complex, [K(2.2.2-cryptand)][U(NAd){OSi(OtBu)3}4] (5), with one or two equivalents of CS2 afforded the trithiocarbonate complex, [K(2.2.2-cryptand)][U(CS3){OSi(OtBu)3}4] (7), which was isolated in 57% yield, with concomitant elimination of the admantyl thiocyanate product, SCNAd. Complex 7 is likely formed by fast nucleophilic addition of a UV terminal sulfide intermediate, resulting from the slow metathesis reaction of the imido complex with CS2, to a second CS2 molecule. The addition of a solution of H2S in thf (1.3 eq.) to 4 afforded the first isolable UV terminal sulfide complex, [K(2.2.2-cryptand)][US{OSi(OtBu)3}4] (8), in 41% yield. Based on DFT calculations, triple-bond character with a strong covalent interaction is suggested for the U–S bond in complex 7. PMID:28970911
Song, Yong Yan; Gong, Ren Rong; Zhang, Zhen; Li, Yuan Hao; Xiao, Li Ying; Zhou, Xue Dong; Fang, Ding Zhi
2011-06-01
Both genetic background and diet have profound effects on plasma lipid profiles. We hypothesized that a high-carbohydrate (high-CHO) diet may affect the ratios of serum lipids and apolipoproteins (apo) differently in subjects with different genotypes of the SstI polymorphism in the apoCIII gene (APOC3). Fifty-six healthy university students (27 males and 29 females, 22.89 ± 1.80 years) were given a washout diet of 54% carbohydrate for 7 days, followed by a high-CHO diet of 70% carbohydrate for 6 days without total energy restriction. Serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apoB100, apoAI, and the APOC3 SstI polymorphism were analyzed. The ratios of serum lipids and apoB100/apoAI were calculated. At baseline, the TG/HDL-C ratio was significantly higher in females, but not in males, with the S2 allele. The differences in the TG/HDL-C ratio between genotypes remained the same after the washout and the high-CHO diet in females. When compared with those before the high-CHO diet, the TC/HDL-C (male S2 carriers: 3.13 ± 1.00 vs 2.36 ± 0.65, P = 0.000; male subjects with the S1S1 genotype: 2.97 ± 0.74 vs 2.09 ± 0.55, P = 0.000; female S2 carriers: 2.68 ± 0.36 vs 2.24 ± 0.37, P = 0.004; female subjects with the S1S1 genotype: 2.69 ± 0.41 vs 2.09 ± 0.31, P = 0.000) and LDL-C/HDL-C (male S2 carriers: 1.44 ± 0.71 vs 1.06 ± 0.26, P = 0.012; male subjects with the S1S1 genotype: 1.35 ± 0.61 vs 1.01 ± 0.29, P = 0.005; female S2 carriers: 1.18 ± 0.33 vs 1.00 ± 0.18, P = 0.049; female subjects with the S1S1 genotype: 1.18 ± 0.35 vs 1.04 ± 0.19, P = 0.026) ratios were significantly decreased after the high-CHO diet regardless of gender and of genotype of the APOC3 SstI polymorphism. However, in female S2 carriers, the TG/HDL-C (1.38 ± 0.46 vs 1.63 ± 0.70, P = 0.039) ratio was significantly increased after the high-CHO diet. In conclusion, the high-CHO diet has favorable effects on the TC/HDL-C and LDL-C/HDL-C ratios regardless of gender and of genotype of the APOC3 SstI polymorphism. Somehow, it enhanced the adverse effect of the S2 allele on the TG/HDL-C ratio only in females.
All-MOCVD-grown BH laser on P-InP substrates
NASA Astrophysics Data System (ADS)
Nishimura, Tadashi; Ishimura, E.; Nakajima, Yasuo; Tada, Hitoshi; Kimura, T.; Ohkura, Y.; Goto, Katsuhiko; Omura, Etsuji; Aiga, Masao
1993-07-01
A very low cw threshold current of 2.5 mA ( 25 degree(s)C) and 8.0 mA ( 80 degree(s)C) with high reliability has been realized in the all-MOCVD grown BH lasers on p-InP substrates. A strained MQW active layer of 1.3 micrometers wavelength and the precise carrier confinement buried structure by MOCVD is employed for the BH lasers. The excellent potential of long lifetime of the all-MOCVD grown laser has also been confirmed. After the high temperature and the high current (100 degree(s)C, 200 mA) aging test, no significant degradation is observed which is comparable with the well-established LPE grown lasers. The BH laser is also operating stably over 3700 hrs under the APC condition of 50 degree(s)C, 10 mW. Finally, an extremely uniform 10-element all-MOCVD grown LD array is demonstrated, which has the threshold current uniformity of 2.4 +/- 0.1 mA ( 25 degree(s)C) and 9.2 +/- 0.2 mA ( 80 degree(s)C). The growth mechanism in the MOCVD is also described.
Coordinated observations of interacting peculiar red giant binaries, 1
NASA Technical Reports Server (NTRS)
Ake, T.
1995-01-01
IUE Observations were begun for a two-year program to monitor the UV variability of three interacting peculiar red giant (PRG) binaries, HD 59643 (C6,s) HD 35155 (S3/2), and HR 1105 (S3.5/2.5). All of these systems were suspected to involve accretion of material from the PRG to a white-dwarf secondary, based mainly on previous IUE investigations. From our earlier surveys of PRG's, they were primary candidates to test the hypothesis that Tc-poor PRG's are formed as a result of mass transfer from a secondary component rather than from internal thermal pulsing while on the asymptotic red giant branch.
Heilmann, Romy M; Grellet, Aurélien; Grützner, Niels; Cranford, Shannon M; Suchodolski, Jan S; Chastant-Maillard, Sylvie; Steiner, Jörg M
2018-04-17
Previous data suggest that fecal S100A12 has clinical utility as a biomarker of chronic gastrointestinal inflammation (idiopathic inflammatory bowel disease) in both people and dogs, but the effect of gastrointestinal pathogens on fecal S100A12 concentrations is largely unknown. The role of S100A12 in parasite and viral infections is also difficult to study in traditional animal models due to the lack of S100A12 expression in rodents. Thus, the aim of this study was to evaluate fecal S100A12 concentrations in a cohort of puppies with intestinal parasites (Cystoisospora spp., Toxocara canis, Giardia sp.) and viral agents that are frequently encountered and known to cause gastrointestinal signs in dogs (coronavirus, parvovirus) as a comparative model. Spot fecal samples were collected from 307 puppies [median age (range): 7 (4-13) weeks; 29 different breeds] in French breeding kennels, and fecal scores (semiquantitative system; scores 1-13) were assigned. Fecal samples were tested for Cystoisospora spp. (C. canis and C. ohioensis), Toxocara canis, Giardia sp., as well as canine coronavirus (CCV) and parvovirus (CPV). S100A12 concentrations were measured in all fecal samples using an in-house radioimmunoassay. Statistical analyses were performed using non-parametric 2-group or multiple-group comparisons, non-parametric correlation analysis, association testing between nominal variables, and construction of a multivariate mixed model. Fecal S100A12 concentrations ranged from < 24-14,363 ng/g. Univariate analysis only showed increased fecal S100A12 concentrations in dogs shedding Cystoisospora spp. (P = 0.0384) and in dogs infected with parvovirus (P = 0.0277), whereas dogs infected with coronavirus had decreased fecal S100A12 concentrations (P = 0.0345). However, shedding of any single enteropathogen did not affect fecal S100A12 concentrations in multivariate analysis (all P > 0.05) in this study. Only fecal score and breed size had an effect on fecal S100A12 concentrations in multivariate analysis (P < 0.0001). An infection with any single enteropathogen tested in this study is unlikely to alter fecal S100A12 concentrations, and these preliminary data are important for further studies evaluating fecal S100A12 concentrations in dogs or when using fecal S100A12 concentrations as a biomarker in patients with chronic idiopathic gastrointestinal inflammation.
VizieR Online Data Catalog: EBHIS spectra and HI column density maps (Winkel+, 2016)
NASA Astrophysics Data System (ADS)
Winkel, B.; Kerp, J.; Floeer, L.; Kalberla, P. M. W.; Ben Bekhti, N.; Keller, R.; Lenz, D.
2015-11-01
The EBHIS 1st data release comprises 21-cm neutral atomic hydrogen data of the Milky Way (-600km/s
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dilbeck, Preston L.; Tang, Qun; Mothersole, David J.
Here, six light-harvesting-2 complexes (LH2) from genetically modified strains of the purple photosynthetic bacterium Rhodobacter (Rb.) sphaeroides were studied using static and ultrafast optical methods and resonance Raman spectroscopy. These strains were engineered to incorporate carotenoids for which the number of conjugated groups (N = N C=C + N C=O) varies from 9 to 15. The Rb. sphaeroides strains incorporate their native carotenoids spheroidene (N = 10) and spheroidenone (N = 11), as well as longer-chain analogues including spirilloxanthin (N = 13) and diketospirilloxantion (N = 15) normally found in Rhodospirillum rubrum. Measurements of the properties of the carotenoid firstmore » singlet excited state (S1) in antennas from the Rb. sphaeroides set show that carotenoid-bacteriochlorophyll a (BChl a) interactions are similar to those in LH2 complexes from various other bacterial species and thus are not significantly impacted by differences in polypeptide composition. Instead, variations in carotenoid-to-BChl a energy transfer are primarily regulated by the N-determined energy of the carotenoid S 1 excited state, which for long-chain (N ≥ 13) carotenoids is not involved in energy transfer. Furthermore, the role of the long-chain carotenoids switches from a lightharvesting supporter (via energy transfer to BChl a) to a quencher of the BChl a S 1 excited state B850*. This quenching is manifested as a substantial (~2-fold) reduction of the B850* lifetime and the B850* fluorescence quantum yield for LH2 housing the longest carotenoids« less
Dilbeck, Preston L.; Tang, Qun; Mothersole, David J.; ...
2016-06-10
Here, six light-harvesting-2 complexes (LH2) from genetically modified strains of the purple photosynthetic bacterium Rhodobacter (Rb.) sphaeroides were studied using static and ultrafast optical methods and resonance Raman spectroscopy. These strains were engineered to incorporate carotenoids for which the number of conjugated groups (N = N C=C + N C=O) varies from 9 to 15. The Rb. sphaeroides strains incorporate their native carotenoids spheroidene (N = 10) and spheroidenone (N = 11), as well as longer-chain analogues including spirilloxanthin (N = 13) and diketospirilloxantion (N = 15) normally found in Rhodospirillum rubrum. Measurements of the properties of the carotenoid firstmore » singlet excited state (S1) in antennas from the Rb. sphaeroides set show that carotenoid-bacteriochlorophyll a (BChl a) interactions are similar to those in LH2 complexes from various other bacterial species and thus are not significantly impacted by differences in polypeptide composition. Instead, variations in carotenoid-to-BChl a energy transfer are primarily regulated by the N-determined energy of the carotenoid S 1 excited state, which for long-chain (N ≥ 13) carotenoids is not involved in energy transfer. Furthermore, the role of the long-chain carotenoids switches from a lightharvesting supporter (via energy transfer to BChl a) to a quencher of the BChl a S 1 excited state B850*. This quenching is manifested as a substantial (~2-fold) reduction of the B850* lifetime and the B850* fluorescence quantum yield for LH2 housing the longest carotenoids« less
CuBi2O4 Prepared by the Polymerized Complex Method for Gas-Sensing Applications.
Choi, Yun-Hyuk; Kim, Dai-Hong; Hong, Seong-Hyeon
2018-05-02
Multicomponent oxides can be extensively explored as alternative gas-sensing materials to binary oxides with their structural and compositional versatilities. In this work, the gas-sensing properties of CuBi 2 O 4 have been investigated toward various reducing gases (C 2 H 5 OH, NH 3 , H 2 , CO, and H 2 S) and oxidizing gas (NO 2 ) for the first time. For this, the powder synthesis has been developed using the polymerized complex method (Pechini method) to obtain a single-phase polycrystalline CuBi 2 O 4 . The defect, optical, and electronic properties in the prepared CuBi 2 O 4 powder were modulated by varying the calcination temperature from 500 to 700 °C. Noticeably, a high concentration of Cu + -oxygen vacancy ([Formula: see text]) defect complexes and isolated Cu 2+ ion clusters was found in the 500 °C-calcined CuBi 2 O 4 , where they were removed through air calcination at higher temperatures (up to 700 °C) while making the compound more stoichiometric. The change in the intrinsic defect concentration with the calcination temperature led to the variation of the electronic band gap energy and hole concentration in CuBi 2 O 4 with the polaronic hopping conduction (activation energy = 0.43 eV). The CuBi 2 O 4 sensor with 500 °C-calcined powder showed the highest gas responses (specifically, 10.4 toward 1000 ppm C 2 H 5 OH at the operating temperature of 400 °C) with the highest defect concentration. As a result, the gas-sensing characteristics of CuBi 2 O 4 are found to be dominantly affected by the intrinsic defect concentration, which is controlled by the calcination temperature. Toward reducing H 2 S and oxidizing NO 2 gases, the multiple reactions arising simultaneously on the surface of the CuBi 2 O 4 sensor govern its response behavior, depending on the gas concentration and the operating temperature. We believe that this work can be a cornerstone for understanding the effect of chemical defect on the gas-sensing characteristics in multicomponent oxides.
Shi, Yan; Sun, Ken; Huo, Lixin; Li, Xiuxiu; Qi, Xuebin; Li, Zhaohui
2017-09-19
Chitosan was used to modify a 13X molecular sieve to improve its cadmium removal capability. After being modified with 2% chitosan-acetate for 2 h at 30 °C, significant uptake of Cd 2+ could be achieved. The uptake of Cd 2+ on the modified 13X molecular sieve followed the Langmuir isotherms with a capacity of 1 mg/g. The kinetics of Cd 2+ removal by modified 13X molecular sieve followed a pseudo second-order reaction, suggesting chemisorption or surface complexation. The Cd 2+ removal with a sorbent dose of 2 g/L from an initial concentration of 100 μg/L reached more than 95% in 90 min. The equilibrium Cd 2+ concentration was <5 μg/L, which meets the requirements of "Standards for Irrigation Water Quality" (GB5084-2005) (10 μg/L) and MCL and MCLG for groundwater and drinking water (5 μg/L) set by United States Environmental Protection Agency.
Stromatolite laminae (Lagoa Vermelha, Brasil) as archives for reservoir age changes
NASA Astrophysics Data System (ADS)
Bruggmann, Sylvie; Vasconcelos, Crisogono; Hajdas, Irka
2016-04-01
As laminated biogenic or abiogenic sedimentary structures [1], stromatolites record environmental changes along growth profiles, revealing possible changes in reservoir ages due to input of older carbon. A modern stromatolite sample was collected in Lagoa Vermelha (100 km east of Rio de Janeiro, Brasil) an area known for upwelling of South Atlantic Central Water (SACW). 34 samples from a transect cutting the lamination were collected with a hand-driller for standard geochemistry and 14C AMS analyses. Shells collected in 2015 were analysed for estimation of the present-day reservoir age. 14C ages of laminae and the reservoir age were used to apply the age-depth model to the stromatolite transect with the OxCal depositional model (Marine13 calibration curve; [2]). Small-scale changes in the composition of laminae report environmental changes, e.g. upwelling. The well-laminated middle part (laminated boundstone; ca. 4cm) of the stromatolite transect was found to have grown in a short time period of less than 100 years (1163-1210 14C y BP), with four excursions towards older 14C ages (ca. 1200 14C y BP). To detect possible changes of marine 14C, calendar years assuming a stable modern reservoir age were used to simulate atmospheric 14C ages with the southern hemisphere IntCal13 atmospheric calibration curve [3]. The offset between the measured and simulated 14C ages indicates a variability of the reservoir age between -99 and 268 14C y with highest reservoir correction found for the layers with indication of environmental changes (e.g. upwelling). Thus, this simulation confirms the occurrence of older carbon and points out the sensitivity of stromatolites for changing reservoir ages. [1] M.A. Semikhatov, C.D. Gebelein, P. Cloud, S.M. Awramik, W.C. Benmore (1979). Stromatolite morphogenesis - progress and problems. Canadian Journal of Earth Sciences, 19:992-1015. [2] P.J. Reimer, E. Bard, A. Bayliss, J. W. Beck, P. G. Blackwell, C. Bronk Ramsey, C. E. Buck, H. Cheng, R.L. Edwards, M. Friedrich, P.M. Grootes, T.P. Guilderson, H. Haflidason, I. Hajdas, C. Hatté, T.J. Heaton, D.L. Hoffmann, A.G. Hogg, K.A. Hughen, K.F. Kaiser, B. Kromer, S.W. Manning, M. Niu, R.W. Reimer, D.A. Richards, E.M. Scott, J. R. Southon, R.A. Staff, C.S.M. Turney, J. van der Plicht (2013). IntCal13 and Marine13 radiocarbon age calibration curves 0-50,000 years cal BP. Radiocarbon 55(4):1869-1887. [3] A.G. Hogg, Q. Hua, P.G. Blackwell, M. Niu, C.E. Buck, T.P. Guilderson, T.J. Heaton, J.G. Palmer, P.J. Reimer, R.W. Reimer, C.S.M. Turney, S.R.H. Zimmerman (2013). Shcal13 southern hemisphere calibration, 0-50,000 years cal BP. Radiocarbon, 55(2):1-15.
Activities in Cu2S-FeS-PbS melts at 1200 °C
NASA Astrophysics Data System (ADS)
Eriç, H.; Timuçin, M.
1981-09-01
The dew-point method was used to determine the vapor pressures of PbS over liquid sulfides of the system Cu2S-FeS-PbS at 1200 °C. From the PbS activity data, activities of Cu2S and FeS were evaluated both in binary and ternary melts by Gibbs-Duhem calculations. The systems Cu2S-PbS and Cu2S-FeS exhibit negative departures from ideal behavior, while the FeS-PbS melts are ideal solutions at 1200 °C.
GW170608: Observation of a 19 Solar-mass Binary Black Hole Coalescence
NASA Astrophysics Data System (ADS)
Abbott, B. P.; Abbott, R.; Abbott, T. D.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Afrough, M.; Agarwal, B.; Agathos, M.; Agatsuma, K.; Aggarwal, N.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allen, G.; Allocca, A.; Altin, P. A.; Amato, A.; Ananyeva, A.; Anderson, S. B.; Anderson, W. G.; Angelova, S. V.; Antier, S.; Appert, S.; Arai, K.; Araya, M. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Atallah, D. V.; Aufmuth, P.; Aulbert, C.; AultONeal, K.; Austin, C.; Avila-Alvarez, A.; Babak, S.; Bacon, P.; Bader, M. K. M.; Bae, S.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Banagiri, S.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, D.; Barkett, K.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Bawaj, M.; Bayley, J. C.; Bazzan, M.; Bécsy, B.; Beer, C.; Bejger, M.; Belahcene, I.; Bell, A. S.; Berger, B. K.; Bergmann, G.; Bero, J. J.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Billman, C. R.; Birch, J.; Birney, R.; Birnholtz, O.; Biscans, S.; Biscoveanu, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blackman, J.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, S.; Bock, O.; Bode, N.; Boer, M.; Bogaert, G.; Bohe, A.; Bondu, F.; Bonilla, E.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bossie, K.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Broida, J. E.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brunett, S.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cabero, M.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T. A.; Calloni, E.; Camp, J. B.; Canepa, M.; Canizares, P.; Cannon, K. C.; Cao, H.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Carney, M. F.; Casanueva Diaz, J.; Casentini, C.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerdá-Durán, P.; Cerretani, G.; Cesarini, E.; Chamberlin, S. J.; Chan, M.; Chao, S.; Charlton, P.; Chase, E.; Chassande-Mottin, E.; Chatterjee, D.; Chatziioannou, K.; Cheeseboro, B. D.; Chen, H. Y.; Chen, X.; Chen, Y.; Cheng, H.-P.; Chia, H.; Chincarini, A.; Chiummo, A.; Chmiel, T.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Q.; Chua, A. J. K.; Chua, S.; Chung, A. K. W.; Chung, S.; Ciani, G.; Ciolfi, R.; Cirelli, C. E.; Cirone, A.; Clara, F.; Clark, J. A.; Clearwater, P.; Cleva, F.; Cocchieri, C.; Coccia, E.; Cohadon, P.-F.; Cohen, D.; Colla, A.; Collette, C. G.; Cominsky, L. R.; Constancio, M., Jr.; Conti, L.; Cooper, S. J.; Corban, P.; Corbitt, T. R.; Cordero-Carrión, I.; Corley, K. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, C. A.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J.-P.; Countryman, S. T.; Couvares, P.; Covas, P. B.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Creighton, J. D. E.; Creighton, T. D.; Cripe, J.; Crowder, S. G.; Cullen, T. J.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dal Canton, T.; Dálya, G.; Danilishin, S. L.; D’Antonio, S.; Danzmann, K.; Dasgupta, A.; Da Silva Costa, C. F.; Dattilo, V.; Dave, I.; Davier, M.; Davis, D.; Daw, E. J.; Day, B.; De, S.; DeBra, D.; Degallaix, J.; De Laurentis, M.; Deléglise, S.; Del Pozzo, W.; Demos, N.; Denker, T.; Dent, T.; De Pietri, R.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; De Rossi, C.; DeSalvo, R.; de Varona, O.; Devenson, J.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Di Giovanni, M.; Di Girolamo, T.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Renzo, F.; Doctor, Z.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Dorrington, I.; Douglas, R.; Dovale Álvarez, M.; Downes, T. P.; Drago, M.; Dreissigacker, C.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dupej, P.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H.-B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Eisenstein, R. A.; Essick, R. C.; Estevez, D.; Etienne, Z. B.; Etzel, T.; Evans, M.; Evans, T. M.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.; Farinon, S.; Farr, B.; Farr, W. M.; Fauchon-Jones, E. J.; Favata, M.; Fays, M.; Fee, C.; Fehrmann, H.; Feicht, J.; Fejer, M. M.; Fernandez-Galiana, A.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Finstad, D.; Fiori, I.; Fiorucci, D.; Fishbach, M.; Fisher, R. P.; Fitz-Axen, M.; Flaminio, R.; Fletcher, M.; Fong, H.; Font, J. A.; Forsyth, P. W. F.; Forsyth, S. S.; Fournier, J.-D.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fries, E. M.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H.; Gadre, B. U.; Gaebel, S. M.; Gair, J. R.; Gammaitoni, L.; Ganija, M. R.; Gaonkar, S. G.; Garcia-Quiros, C.; Garufi, F.; Gateley, B.; Gaudio, S.; Gaur, G.; Gayathri, V.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; George, D.; George, J.; Gergely, L.; Germain, V.; Ghonge, S.; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.; Glover, L.; Goetz, E.; Goetz, R.; Gomes, S.; Goncharov, B.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gorodetsky, M. L.; Gossan, S. E.; Gosselin, M.; Gouaty, R.; Grado, A.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greco, G.; Green, A. C.; Gretarsson, E. M.; Groot, P.; Grote, H.; Grunewald, S.; Gruning, P.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Halim, O.; Hall, B. R.; Hall, E. D.; Hamilton, E. Z.; Hammond, G.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hannuksela, O. A.; Hanson, J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Haster, C.-J.; Haughian, K.; Healy, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hinderer, T.; Hoak, D.; Hofman, D.; Holt, K.; Holz, D. E.; Hopkins, P.; Horst, C.; Hough, J.; Houston, E. A.; Howell, E. J.; Hreibi, A.; Hu, Y. M.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Indik, N.; Inta, R.; Intini, G.; Isa, H. N.; Isac, J.-M.; Isi, M.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jiménez-Forteza, F.; Johnson, W. W.; Johnson-McDaniel, N. K.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; Junker, J.; Kalaghatgi, C. V.; Kalogera, V.; Kamai, B.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Kapadia, S. J.; Karki, S.; Karvinen, K. S.; Kasprzack, M.; Katolik, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kawabe, K.; Kéfélian, F.; Keitel, D.; Kemball, A. J.; Kennedy, R.; Kent, C.; Key, J. S.; Khalili, F. Y.; Khan, I.; Khan, S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, Chunglee; Kim, J. C.; Kim, K.; Kim, W.; Kim, W. S.; Kim, Y.-M.; Kimbrell, S. J.; King, E. J.; King, P. J.; Kinley-Hanlon, M.; Kirchhoff, R.; Kissel, J. S.; Kleybolte, L.; Klimenko, S.; Knowles, T. D.; Koch, P.; Koehlenbeck, S. M.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Krämer, C.; Kringel, V.; Krishnan, B.; Królak, A.; Kuehn, G.; Kumar, P.; Kumar, R.; Kumar, S.; Kuo, L.; Kutynia, A.; Kwang, S.; Lackey, B. D.; Lai, K. H.; Landry, M.; Lang, R. N.; Lange, J.; Lantz, B.; Lanza, R. K.; Lartaux-Vollard, A.; Lasky, P. D.; Laxen, M.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lee, C. H.; Lee, H. K.; Lee, H. M.; Lee, H. W.; Lee, K.; Lehmann, J.; Lenon, A.; Leonardi, M.; Leroy, N.; Letendre, N.; Levin, Y.; Li, T. G. F.; Linker, S. D.; Littenberg, T. B.; Liu, J.; Lo, R. K. L.; Lockerbie, N. A.; London, L. T.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lousto, C. O.; Lovelace, G.; Lück, H.; Lumaca, D.; Lundgren, A. P.; Lynch, R.; Ma, Y.; Macas, R.; Macfoy, S.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña Hernandez, I.; Magaña-Sandoval, F.; Magaña Zertuche, L.; Magee, R. M.; Majorana, E.; Maksimovic, I.; Man, N.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markakis, C.; Markosyan, A. S.; Markowitz, A.; Maros, E.; Marquina, A.; Martelli, F.; Martellini, L.; Martin, I. W.; Martin, R. M.; Martynov, D. V.; Mason, K.; Massera, E.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Mastrogiovanni, S.; Matas, A.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McCuller, L.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McNeill, L.; McRae, T.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Mehmet, M.; Meidam, J.; Mejuto-Villa, E.; Melatos, A.; Mendell, G.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Metzdorff, R.; Meyers, P. M.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, A. L.; Miller, B. B.; Miller, J.; Millhouse, M.; Milovich-Goff, M. C.; Minazzoli, O.; Minenkov, Y.; Ming, J.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moffa, D.; Moggi, A.; Mogushi, K.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, C. J.; Moraru, D.; Moreno, G.; Morriss, S. R.; Mours, B.; Mow-Lowry, C. M.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Muñiz, E. A.; Muratore, M.; Murray, P. G.; Napier, K.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Neilson, J.; Nelemans, G.; Nelson, T. J. N.; Nery, M.; Neunzert, A.; Nevin, L.; Newport, J. M.; Newton, G.; Ng, K. K. Y.; Nguyen, T. T.; Nichols, D.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Noack, A.; Nocera, F.; Nolting, D.; North, C.; Nuttall, L. K.; Oberling, J.; O’Dea, G. D.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Ohme, F.; Okada, M. A.; Oliver, M.; Oppermann, P.; Oram, Richard J.; O’Reilly, B.; Ormiston, R.; Ortega, L. F.; O’Shaughnessy, R.; Ossokine, S.; Ottaway, D. J.; Overmier, H.; Owen, B. J.; Pace, A. E.; Page, J.; Page, M. A.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, Howard; Pan, Huang-Wei; Pang, B.; Pang, P. T. H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Parida, A.; Parker, W.; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patil, M.; Patricelli, B.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Perez, C. J.; Perreca, A.; Perri, L. M.; Pfeiffer, H. P.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pirello, M.; Pitkin, M.; Poe, M.; Poggiani, R.; Popolizio, P.; Porter, E. K.; Post, A.; Powell, J.; Prasad, J.; Pratt, J. W. W.; Pratten, G.; Predoi, V.; Prestegard, T.; Prijatelj, M.; Principe, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L. G.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rajan, C.; Rajbhandari, B.; Rakhmanov, M.; Ramirez, K. E.; Ramos-Buades, A.; Rapagnani, P.; Raymond, V.; Razzano, M.; Read, J.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Ren, W.; Reyes, S. D.; Ricci, F.; Ricker, P. M.; Rieger, S.; Riles, K.; Rizzo, M.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, R.; Romel, C. L.; Romie, J. H.; Rosińska, D.; Ross, M. P.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Rutins, G.; Ryan, K.; Sachdev, S.; Sadecki, T.; Sadeghian, L.; Sakellariadou, M.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sampson, L. M.; Sanchez, E. J.; Sanchez, L. E.; Sanchis-Gual, N.; Sandberg, V.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O.; Savage, R. L.; Sawadsky, A.; Schale, P.; Scheel, M.; Scheuer, J.; Schmidt, J.; Schmidt, P.; Schnabel, R.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, E.; Schuette, D.; Schulte, B. W.; Schutz, B. F.; Schwalbe, S. G.; Scott, J.; Scott, S. M.; Seidel, E.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Shaddock, D. A.; Shaffer, T. J.; Shah, A. A.; Shahriar, M. S.; Shaner, M. B.; Shao, L.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sieniawska, M.; Sigg, D.; Silva, A. D.; Singer, L. P.; Singh, A.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, B.; Smith, J. R.; Smith, R. J. E.; Somala, S.; Son, E. J.; Sonnenberg, J. A.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Spencer, A. P.; Srivastava, A. K.; Staats, K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stevenson, S. P.; Stone, R.; Stops, D. J.; Strain, K. A.; Stratta, G.; Strigin, S. E.; Strunk, A.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sunil, S.; Suresh, J.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.; Tait, S. C.; Talbot, C.; Talukder, D.; Tanner, D. B.; Tápai, M.; Taracchini, A.; Tasson, J. D.; Taylor, J. A.; Taylor, R.; Tewari, S. V.; Theeg, T.; Thies, F.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Toland, K.; Tonelli, M.; Tornasi, Z.; Torres-Forné, A.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trinastic, J.; Tringali, M. C.; Trozzo, L.; Tsang, K. W.; Tse, M.; Tso, R.; Tsukada, L.; Tsuna, D.; Tuyenbayev, D.; Ueno, K.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; Van Den Broeck, C.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Varma, V.; Vass, S.; Vasúth, M.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Venugopalan, G.; Verkindt, D.; Vetrano, F.; Viceré, A.; Viets, A. D.; Vinciguerra, S.; Vine, D. J.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, M.; Walet, R.; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, J. Z.; Wang, W. H.; Wang, Y. F.; Ward, R. L.; Warner, J.; Was, M.; Watchi, J.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Wessel, E. K.; Weßels, P.; Westerweck, J.; Westphal, T.; Wette, K.; Whelan, J. T.; Whiting, B. F.; Whittle, C.; Wilken, D.; Williams, D.; Williams, R. D.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Woehler, J.; Wofford, J.; Wong, K. W. K.; Worden, J.; Wright, J. L.; Wu, D. S.; Wysocki, D. M.; Xiao, S.; Yamamoto, H.; Yancey, C. C.; Yang, L.; Yap, M. J.; Yazback, M.; Yu, Hang; Yu, Haocun; Yvert, M.; Zadrożny, A.; Zanolin, M.; Zelenova, T.; Zendri, J.-P.; Zevin, M.; Zhang, L.; Zhang, M.; Zhang, T.; Zhang, Y.-H.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, S. J.; Zhu, X. J.; Zimmerman, A. B.; Zucker, M. E.; Zweizig, J.; (LIGO Scientific Collaboration; Virgo Collaboration
2017-12-01
On 2017 June 8 at 02:01:16.49 UTC, a gravitational-wave (GW) signal from the merger of two stellar-mass black holes was observed by the two Advanced Laser Interferometer Gravitational-Wave Observatory detectors with a network signal-to-noise ratio of 13. This system is the lightest black hole binary so far observed, with component masses of {12}-2+7 {M}ȯ and {7}-2+2 {M}ȯ (90% credible intervals). These lie in the range of measured black hole masses in low-mass X-ray binaries, thus allowing us to compare black holes detected through GWs with electromagnetic observations. The source’s luminosity distance is {340}-140+140 {Mpc}, corresponding to redshift {0.07}-0.03+0.03. We verify that the signal waveform is consistent with the predictions of general relativity.
Spacecraft On-Board Information Extraction Computer (SOBIEC)
NASA Technical Reports Server (NTRS)
Eisenman, David; Decaro, Robert E.; Jurasek, David W.
1994-01-01
The Jet Propulsion Laboratory is the Technical Monitor on an SBIR Program issued for Irvine Sensors Corporation to develop a highly compact, dual use massively parallel processing node known as SOBIEC. SOBIEC couples 3D memory stacking technology provided by nCUBE. The node contains sufficient network Input/Output to implement up to an order-13 binary hypercube. The benefit of this network, is that it scales linearly as more processors are added, and it is a superset of other commonly used interconnect topologies such as: meshes, rings, toroids, and trees. In this manner, a distributed processing network can be easily devised and supported. The SOBIEC node has sufficient memory for most multi-computer applications, and also supports external memory expansion and DMA interfaces. The SOBIEC node is supported by a mature set of software development tools from nCUBE. The nCUBE operating system (OS) provides configuration and operational support for up to 8000 SOBIEC processors in an order-13 binary hypercube or any subset or partition(s) thereof. The OS is UNIX (USL SVR4) compatible, with C, C++, and FORTRAN compilers readily available. A stand-alone development system is also available to support SOBIEC test and integration.
Characteristics of Aerosol Volume Distributions Measured at Meppen, W. Germany.
1983-10-01
RH <c7S% RH ;0S% .,. .. . ._ .,.z ., ,e, - 103M ~m3c -3 6(67) 143 (82) 2110a,3 m3 [77)]7S (51067) y1 < 1&3tsm 3cm-3 443 (332) 406 (467) V2 < 3xI0’ssN3M...function of relative humidity for the Meppen round station data. .V > 102 RH < 70% RH >70%" Modes Number Number 10 a 0 2 a-m 0 0 a-c 24 9 100o , , o...volume (mass) modes. RH < and > 80%. The number of occurrences expected Note that in this figure of the PMS data, dV/d logr is from random chance appears
Modulating of the pnicogen-bonding by a H⋯π interaction: An ab initio study.
Esrafili, Mehdi D; Sadr-Mousavi, Asma
2017-08-01
An ab initio study of the cooperativity in XH 2 P⋯NCH⋯Z and XH 2 P⋯CNH⋯Z complexes (X=F, Cl, Br, CN, NC; Z=C 2 H 2 ,C 6 H 6 ) connected by pnicogen-bonding and H⋯π interactions is carried out by means of MP2 computational method. A detailed analysis of the structures, interaction energies and bonding properties is performed on these systems. For each set of the complexes considered, a favorable cooperativity is observed, especially in X=F and CN complexes. However, for a given X or Z, the amount of cooperativity effects in XH 2 P⋯CNH⋯Z complexes are more important than XH 2 P⋯NCH⋯Z counterparts. Besides, the influence of a H⋯π interaction on a P⋯N (C) bond is more pronounced than that of a P⋯N (C) bond on a H⋯π bond. The quantum theory of atoms in molecules shows that ternary complexes have increased electron densities at their bond critical points relative to the corresponding binary systems. The results also indicate that the strength of the P⋯N(C) and H⋯π interactions increases in the presence of the solvent. Copyright © 2017 Elsevier Inc. All rights reserved.
Field Studies for Secondary Organic Aerosol in the Transboundary Air
NASA Astrophysics Data System (ADS)
Irei, S.; Takami, A.; Sadanaga, Y.; Nozoe, S.; Hayashi, M.; Hara, K.; Arakaki, T.; Hatakeyama, S.; Miyoshi, T.; Yokouchi, Y.; Bandow, H.
2014-12-01
To study formation of secondary organic aerosol (SOA) in the air outflowed from the Chinese continent and its fraction in an urban city located in downwind, we have conducted field studies at two background sites and one urban site in the western Japan: the Cape Hedo Aerosol and Atmospheric Monitoring Station (26.9˚N, 128.3˚E), the Fukue Atmospheric Monitoring Station (32.8˚N, 128.7˚E), and Fukuoka University (33.6˚N, 130.4˚E), respectively. During the studies, stable carbon isotope ratio (δ13C) of low-volatile water-soluble organic carbon (LV-WSOC) was measured in 24 h collected filter samples of total suspended particulate matter. Concentration of fine organic aerosol and the proportion of the signal at m/z 44 (ions from the carboxyl group) in the organic mass spectra (f44) were also measured by Aerodyne aerosol mass spectrometers. Limited to the Fukue site only, mixing ratios of trace gas species, such as aromatic hydrocarbons, NOx, and NOy, were also measured using GC-FID and NOx and NOyanalyzers for estimation of photochemical age (t[OH]). A case study in December 2010 showed that plots of δ13C versus f44 showed systematic variations at Hedo and Fukue. However, their trends were opposite. At Fukue the trend was consistent in the plot of δ13C of LV-WSOC versus t[OH] estimated by the NOx/NOy or the hydrocarbon ratios, indicating influence of SOA. The systematic trends aforementioned qualitatively agreed with a binary mixture model of SOA with background LV-WSOC having the f44 of ~0.06 and the δ13C of -17‰ or higher, implication of some influence of primary emission associated with C4plants. Given that the LV-WSOC at the urban Fukuoka site was a binary mixture, a mass balance for δ13C was constructed below. In the equation, δ13CMix, δ13CLocal, δ13CTrans, and FLocal are δ13C of binary LV-WSOC mixture, δ13C of LV-WSOC from local emission origin, δ13C of LV-WSOC from transboundary pollution origin, and a fraction of LV-WSOC from local emission origin in the mixture, respectively. We applied d13C values at Fukuoka and Fukue to δ13CMix and δ13CTrans, respectively, and δ13C of -27‰ for vehicular emission to δ13CLocal. The preliminary results demonstrated that, except some negative FLocal, the majority of calculated FLocal ranged from 4% to 86% and the lower FLocal, the higher LV-WSOC concentration.
Wang, Jianwei; Zhang, Yong; Wang, Lin-Wang
2015-07-31
We propose a systematic approach that can empirically correct three major errors typically found in a density functional theory (DFT) calculation within the local density approximation (LDA) simultaneously for a set of common cation binary semiconductors, such as III-V compounds, (Ga or In)X with X = N,P,As,Sb, and II-VI compounds, (Zn or Cd)X, with X = O,S,Se,Te. By correcting (1) the binary band gaps at high-symmetry points , L, X, (2) the separation of p-and d-orbital-derived valence bands, and (3) conduction band effective masses to experimental values and doing so simultaneously for common cation binaries, the resulting DFT-LDA-based quasi-first-principles methodmore » can be used to predict the electronic structure of complex materials involving multiple binaries with comparable accuracy but much less computational cost than a GW level theory. This approach provides an efficient way to evaluate the electronic structures and other material properties of complex systems, much needed for material discovery and design.« less
NASA Astrophysics Data System (ADS)
Wang, Jianwei; Zhang, Yong; Wang, Lin-Wang
2015-07-01
We propose a systematic approach that can empirically correct three major errors typically found in a density functional theory (DFT) calculation within the local density approximation (LDA) simultaneously for a set of common cation binary semiconductors, such as III-V compounds, (Ga or In)X with X =N ,P ,As ,Sb , and II-VI compounds, (Zn or Cd)X , with X =O ,S ,Se ,Te . By correcting (1) the binary band gaps at high-symmetry points Γ , L , X , (2) the separation of p -and d -orbital-derived valence bands, and (3) conduction band effective masses to experimental values and doing so simultaneously for common cation binaries, the resulting DFT-LDA-based quasi-first-principles method can be used to predict the electronic structure of complex materials involving multiple binaries with comparable accuracy but much less computational cost than a GW level theory. This approach provides an efficient way to evaluate the electronic structures and other material properties of complex systems, much needed for material discovery and design.
The effect of trace mineral fortification level and source on performance of dairy cattle.
Nocek, J E; Socha, M T; Tomlinson, D J
2006-07-01
Five hundred seventy-three cows, balanced by parity and 305-d mature equivalent at dry off, were assigned to 1 of 4 treatments: 1) 75% complexed trace minerals (CTM; 75C): Zn, Mn, Cu, and Co supplied at 75% of NRC (2001) guidelines by Zn-, Mn-, and Cu-specific AA complexes, and cobalt glucoheptonate; 2) 100% inorganic (100I): Zn, Mn, Cu, and Co supplied at 100% of NRC (2001) requirements by sulfate sources; 3) 100% complexed (100C): Zn, Mn, Cu, and Co supplied at 100% of NRC (2001) requirements by CTM; and 4) complexed/ inorganic (C/I): Zn and Cu supplied at 100% of NRC (2001) requirements using a combination of CTM and sulfates and Co and Mn supplied with sources at 9.1 and 3.3 times NRC (2001) requirements using a combination of CTM and sulfates. All percentages of Zn, Cu, Mn, and Co relative to NRC (2001) reflect supplemental contributions and do not include basal diet contributions. Experimental periods were dry period 1, full lactation 1, dry period 2, and 200 d into the subsequent lactation. Reproductive, health, and production information was collected during both lactations. Claw evaluations were conducted at trial start, 150 d into lactation 1, at the end of lactation 1, and 150 d into lactation 2. During lactation 1, C/I cows produced more milk, fat-corrected milk, energy-corrected milk, and fat than 100I cows. During lactation 2, yields of milk, fat-corrected milk, energy-corrected milk, fat, and protein were higher for 100C and C/I cows than for 75C or 100I cows. Fat percentage was highest for 100C cows with no treatment effect on protein content. During lactations 1 and 2, C/I cows had fewer days to first estrus than cows receiving the other treatments. During lactation 2, C/ I cows had fewer services per conception and days open. There were no significant effects of treatment on health. White line separation incidence was lower for 100I cows than 75C cows, whereas heel erosion was higher for the 100I cows than for the C/I cows. Fortification of trace elements with inorganic and complexed sources at or above NRC requirements improved reproductive and productive performance. In addition, cows can be supplemented with CTM at 75% of NRC requirements with no reduction in performance compared with supplementing at 100% of NRC requirements using only sulfate sources of Zn, Mn, Cu, and Co.
Vogl, Thomas; Gharibyan, Anna L.; Morozova-Roche, Ludmilla A.
2012-01-01
S100A8 and S100A9 are EF-hand Ca2+ binding proteins belonging to the S100 family. They are abundant in cytosol of phagocytes and play critical roles in numerous cellular processes such as motility and danger signaling by interacting and modulating the activity of target proteins. S100A8 and S100A9 expression levels increased in many types of cancer, neurodegenerative disorders, inflammatory and autoimmune diseases and they are implicated in the numerous disease pathologies. The Ca2+ and Zn2+-binding properties of S100A8/A9 have a pivotal influence on their conformation and oligomerization state, including self-assembly into homo- and heterodimers, tetramers and larger oligomers. Here we review how the unique chemical and conformational properties of individual proteins and their structural plasticity at the quaternary level account for S100A8/A9 functional diversity. Additional functional diversification occurs via non-covalent assembly into oligomeric and fibrillar amyloid complexes discovered in the aging prostate and reproduced in vitro. This process is also regulated by Ca2+and Zn2+-binding and effectively competes with the formation of the native complexes. High intrinsic amyloid-forming capacity of S100A8/A9 proteins may lead to their amyloid depositions in numerous ailments characterized by their elevated expression patterns and have additional pathological significance requiring further thorough investigation. PMID:22489132
NASA Astrophysics Data System (ADS)
Supee, A.; Ichimura, M.
2017-12-01
Heterostructures which consist of ZnO and FeS x O y were deposited via electrochemical deposition (ECD) for application to solar cells. Galvanostatic ECD was used in FeS x O y deposition with a solution containing 100 mM Na2S2O3 and 30 mM FeSO4. To alter the film properties, L(+)-tartaric acid (C4H6O6) and lactic acid [CH3CH(OH)COOH] were introduced as the complexing agents into the FeS x O y deposition solution. Larger film thickness and smaller oxygen content were obtained for the films deposited with the complexing agents. ZnO was deposited on FeS x O y by two-step pulse ECD from a solution containing Zn(NO3)2. For the ZnO/FeS x O y heterostructures fabricated with/without complexing agents, rectifying properties were confirmed in the current density-voltage ( J- V) characteristics. However, photovoltaic properties were not improved with addition of both complexing agents.
1991-01-01
0 ) 5 M ’ON It 0 0 ) .1 0 LJ at 0 >- < <" C13- IN cn Md z (- 5 1 2 0 MI (ANlI d 0 < x S-40 0 ’CO C"’ I -4 did I= >. x ac a 0 z itE I( M... 0 : 4D 40T 4 ) 4 -1<<<i 14 4- 0 41-I40) -< <’ យ (00 < 00 < 00<< 40 ’a 0 < 40U 1(100( if0 .4 .. 0 00-" . . 5 . -44"-4 C.J 13 A"" -444 440 44 400 0 )00 0 ...00) N >- z 2 2 222
Sharma, Manab; Yameen, Haneen Simaan; Tumanskii, Boris; Filimon, Sabina-Alexandra; Tamm, Matthias; Eisen, Moris S
2012-10-17
The use of bis(1,3-di-tert-butylimidazolin-2-iminato) titanium dichloride (1) and dimethyl (2) complexes in the polymerization of propylene is presented. The complexes were activated using different amounts of methylalumoxane (MAO), giving in each case a very active catalytic mixture and producing polymers with a narrow molecular weight distribution (polydispersity = 1.10). The use of the cocatalyst triphenylcarbenium (trityl) tetra(pentafluorophenyl)borate totally inhibits the reaction, producing the corresponding bis(1,3-di-tert-butylimidazolin-2-iminato) titanium(III) methyl complex, the trityl radical ((•)CPh(3)), the anionic MeB(C(6)F(5))(4)(-), B(C(6)F(5))(3), and the bis(1,3-di-tert-butylimidazolin-2-iminato) titanium(IV) dimethyl·B(C(6)F(5))(3) complex. The use of a combination of physical methods such as NMR, ESR-C(60), and MALDI-TOF analyses enabled us to propose a plausible mechanism for the polymerization of propylene, presenting that the polymerization is mainly carried out in a living fashion. In addition, we present a slow equilibrium toward a small amount of a dormant species responsible for 2,1-misinsertions and chain transfer processes.
England, Jason; Farquhar, Erik R; Guo, Yisong; Cranswick, Matthew A; Ray, Kallol; Münck, Eckard; Que, Lawrence
2011-04-04
Currently, there are only a handful of synthetic S = 2 oxoiron(IV) complexes. These serve as models for the high-spin (S = 2) oxoiron(IV) species that have been postulated, and confirmed in several cases, as key intermediates in the catalytic cycles of a variety of nonheme oxygen activating enzymes. The trigonal bipyramidal complex [Fe(IV)(O)(TMG(3)tren)](2+) (1) was both the first S = 2 oxoiron(IV) model complex to be generated in high yield and the first to be crystallographically characterized. In this study, we demonstrate that the TMG(3)tren ligand is also capable of supporting a tricationic cyanoiron(IV) unit, [Fe(IV)(CN)(TMG(3)tren)](3+) (4). This complex was generated by electrolytic oxidation of the high-spin (S = 2) iron(II) complex [Fe(II)(CN)(TMG(3)tren)](+) (2), via the S = 5/2 complex [Fe(III)(CN)(TMG(3)tren)](2+) (3), the progress of which was conveniently monitored by using UV-vis spectroscopy to follow the growth of bathochromically shifting ligand-to-metal charge transfer (LMCT) bands. A combination of X-ray absorption spectroscopy (XAS), Mössbauer and NMR spectroscopies was used to establish that 4 has a S = 0 iron(IV) center. Consistent with its diamagnetic iron(IV) ground state, extended X-ray absorption fine structure (EXAFS) analysis of 4 indicated a significant contraction of the iron-donor atom bond lengths, relative to those of the crystallographically characterized complexes 2 and 3. Notably, 4 has an Fe(IV/III) reduction potential of ∼1.4 V vs Fc(+/o), the highest value yet observed for a monoiron complex. The relatively high stability of 4 (t(1/2) in CD(3)CN solution containing 0.1 M KPF(6) at 25 °C ≈ 15 min), as reflected by its high-yield accumulation via slow bulk electrolysis and amenability to (13)C NMR at -40 °C, highlights the ability of the sterically protecting, highly basic peralkylguanidyl donors of the TMG(3)tren ligand to support highly charged high-valent complexes.
England, Jason; Farquhar, Erik R.; Guo, Yisong; Cranswick, Matthew A.; Ray, Kallol
2011-01-01
Currently, there are only a handful of synthetic S = 2 oxoiron(IV) complexes. These serve as models for the high-spin (S = 2) oxoiron(IV) species that have been postulated, and confirmed in several cases, as key intermediates in the catalytic cycles of a variety of non-heme oxygen activating enzymes. The trigonal bipyramidal complex [FeIV(O)(TMG3tren)]2+ (1) was both the first S = 2 oxoiron(IV) model complex to be generated in high yield and the first to be crystallographically characterized. In this study, we demonstrate that the TMG3tren ligand is also capable of supporting a tricationic cyanoiron(IV) unit, [FeIV(CN)(TMG3tren)]3+ (4). This complex was generated by electrolytic oxidation of the high-spin (S = 2) iron(II) complex [FeII(CN)(TMG3tren)]+ (2), via the S = 5/2 complex [FeIII(CN)(TMG3tren)]2+ (3), the progress of which was conveniently monitored by using UV-Vis spectroscopy to follow the growth of bathochromically shifting LMCT bands. A combination of XAS, Mössbauer and NMR spectroscopies was used to establish that 4 has a S = 0 iron(IV) center. Consistent with its diamagnetic iron(IV) ground state, EXAFS analysis of 4 indicated a significant contraction of the iron-donor atom bond lengths, relative to those of the crystallographically characterized complexes 2 and 3. Notably, 4 has an FeIV/III reduction potential of ~1.4 V vs Fc+/o, the highest value yet observed for a monoiron complex. The relatively high stability of 4 (t1/2 in CD3CN solution containing 0.1 M KPF6 at 25 °C ≈ 15 min), as reflected by its high-yield accumulation via slow bulk electrolysis and amenability to 13C NMR at −40 °C, highlights the ability of the sterically protecting, highly basic peralkylguanidyl donors of the TMG3tren ligand to support highly charged high-valent complexes. PMID:21381646
Espa, Davide; Pilia, Luca; Marchiò, Luciano; Artizzu, Flavia; Serpe, Angela; Mercuri, Maria Laura; Simão, Dulce; Almeida, Manuel; Pizzotti, Maddalena; Tessore, Francesca; Deplano, Paola
2012-03-28
The mixed-ligand dithiolene complex [Pt(Bz(2)pipdt)(dcbdt)] (1) bearing the two ligands Bz(2)pipdt = 1,4-dibenzyl-piperazine-3,2-dithione and dcbdt = dicyanobenzodithiolato, has been synthesized, characterized and studied to evaluate its second-order optical nonlinearity. The dithione/dithiolato character of the two ligands gives rise to an asymmetric distribution of the charge in the molecule. This is reflected by structural data showing that in the C(2)S(2)PtS(2)C(2) dithiolene core the four sulfur atoms define a square-planar coordination environment of the metal where the Pt-S bond distances involving the two ligands are similar, while the C-S bond distances in the C(2)S(2) units exhibit a significant difference in Bz(2)pipdt (dithione) and dcbdt (dithiolato). 1 shows a moderately strong absorption peak in the visible region, which can be related to a HOMO-LUMO transition, where the dcbdt ligand (dithiolato) contributes mostly to the HOMO, and the Bz(2)pipdt one (dithione) mostly to the LUMO. Thus this transition has ligand-to-ligand charge transfer (CT) character with some contribution of the metal and undergoes negative solvatochromism and molecular quadratic optical nonlinearity (μβ(0) = -1296 × 10(-48) esu), which was determined by the EFISH (electric-field-induced second-harmonic generation) technique and compared with the values of similar complexes on varying the dithiolato ligand (mnt = maleonitriledithiolato, dmit = 2-thioxo-1,3-dithiole-4,5-dithiolato). Theoretical calculations help to elucidate the role of the dithiolato ligands in affecting the molecular quadratic optical nonlinearity of these complexes.
Surface segregation on Fe3%Si0.04%VC(100) single crystal surfaces
NASA Astrophysics Data System (ADS)
Uebing, C.; Viefhaus, H.
1990-10-01
Surface segregation phenomena on (100) oriented single crystal surfaces of the ferritic Fe-3%Si-0.04%V-C alloy were investigated by AES and LEED. At temperatures below 635 °C vanadium and carbon cosegregation is observed after prolonged heating. At thermodynamic equilibrium the substrate surface is saturated with the binary surface compound VC. The two-dimensional VC is epitaxially arranged on the substrate surface as indicated by LEED investigations. Its structure corresponds to the (100) plane of the three-dimensional VC with rocksalt structure. Sharp above 635 °C the surface compound VC is dissolved into the bulk. At higher temperatures the substrate surface is covered with segregated silicon forming a c(2 × 2) structure. This surface phase transition is reversible. Because of the low concentration and slow diffusion of vanadium, non-equilibrium surface states are formed as intermediates upon segregation of silicon and carbon. Below 500 °C a disordered graphite layer with a characteristical asymmetrical C Auger peak is observed on the substrate surface. Above 500 °C carbon segregation leads to the formation of an ordered c(2 × 2) structure with a symmetrical C Auger peak being characteristic for carbidic or atomically adsorbed species. At increasing temperatures silicon segregation takes place leading to a c(2 × 2) structure. Between silicon and carbon site competition is effective.
Ruas, Alexandre; Bernard, Olivier; Caniffi, Barbara; Simonin, Jean-Pierre; Turq, Pierre; Blum, Lesser; Moisy, Philippe
2006-02-23
This work is aimed at a description of the thermodynamic properties of highly concentrated aqueous solutions of uranyl nitrate at 25 degrees C. A new resolution of the binding mean spherical approximation (BIMSA) theory, taking into account 1-1 and also 1-2 complex formation, is developed and used to reproduce, from a simple procedure, experimental uranyl nitrate osmotic coefficient variation with concentration. For better consistency of the theory, binary uranyl perchlorate and chloride osmotic coefficients are also calculated. Comparison of calculated and experimental values is made. The possibility of regarding the ternary system UO(2)(NO(3))(2)/HNO(3)/H(2)O as a "simple" solution (in the sense of Zdanovskii, Stokes, and Robinson) is examined from water activity and density measurements. Also, an analysis of existing uranyl nitrate binary data is proposed and compared with our obtained data. On the basis of the concept of "simple" solution, values for density and water activity for the binary system UO(2)(NO(3))(2)/H(2)O are proposed in a concentration range on which uranyl nitrate precipitates from measurements on concentrated solutions of the ternary system UO(2)(NO(3))(2)/HNO(3)/H(2)O. This new set of binary data is "fictive" in the sense that the real binary system is not stable chemically. Finally, a new, interesting predictive capability of the BIMSA theory is shown.
Batissoco, Ana Carla; Abreu-Silva, Ronaldo Serafim; Braga, Maria Cristina Célia; Lezirovitz, Karina; Della-Rosa, Valter; Alfredo, Tabith; Otto, Paulo Alberto; Mingroni-Netto, Regina Célia
2009-02-01
Hereditary nonsyndromic deafness is an autosomal recessive condition in about 80% of cases, and point mutations in the GJB2 gene (connexin 26) and two deletions in the GJB6 gene (connexin 30), del(GJB6-D13S1830) and del(GJB6-D13S1854), are reported to account for 50% of recessive deafness. Aiming at establishing the frequencies of GJB2 mutations and GJB6 deletions in the Brazilian population, we screened 300 unrelated individuals with hearing impairment, who were not affected by known deafness related syndromes. We firstly screened the most frequently reported mutations, c.35delG and c.167delT in the GJB2 gene, and del(GJB6-D13S1830) and del(GJB6-D13S1854) in the GJB6 gene, through specific techniques. The detected c.35delG and c.167delT mutations were validated by sequencing. Other mutations in the GJB2 gene were screened by single-strand conformation polymorphism and the coding region was sequenced when abnormal patterns were found. Pathogenic mutations in GJB2 and GJB6 genes were detected in 41 individuals (13.7%), and 80.5% (33/41) presented these mutations in homozygosis or compound heterozygosis, thus explaining their hearing defect. The c.35delG in the GJB2 gene was the most frequent mutation (37/300; 12.4%), detected in 23% familial and 6.2% the sporadic cases. The second most frequent mutation (1%; 3/300) was the del(GJB6-D13S1830), always found associated with the c.35delG mutation. Nineteen different sequence variations were found in the GJB2 gene. In addition to the c.35delG mutation, nine known pathogenic alterations were detected c.167delT, p.Trp24X, p.Val37Ile, c.176_191del16, c.235delC, p.Leu90Pro, p.Arg127His, c.509insA, and p.Arg184Pro. Five substitutions had been previously considered benign polymorphisms: c.-15C>T, p.Val27Ile, p.Met34Thr, p.Ala40Ala, and p.Gly160Ser. Two previously reported mutations of unknown pathogenicity were found (p.Lys168Arg, and c.684C>A), and two novel substitutions, p.Leu81Val (c.G241C) and p.Met195Val (c.A583G), both in heterozygosis without an accompanying mutation in the other allele. None of these latter four variants of undefined status was present in a sample of 100 hearing controls. The present study demonstrates that mutations in the GJB2 gene and del(GJB6 D13S1830) are important causes of hearing impairment in Brazil, thus justifying their screening in a routine basis. The diversity of variants in our sample reflects the ethnic heterogeneity of the Brazilian population.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Darsell, Jens T.; Weil, K. Scott
2007-05-16
As a means of increasing the use temperature of ceramic-ceramic and ceramic-metal air brazes, palladium was investigated as possible ternary addition to the currently employed silver - copper oxide system. The silver component was directly substituted with palladium to form the following series of alloys: (100-y)[(100-z)Pd - (z)Ag] - (y)CuOx where y = 0 - 34 mol% CuOx, z = 50 - 100 mol% silver, and x = 0, 0.5, and 1, denoting copper metal, Cu2O, or CuO. From differential scanning calorimetry, it was determined that the addition of palladium causes an increase in the solidus and liquidus temperatures ofmore » the resulting Pd-Ag-CuO brazes. In general, the liquidus was found to increase by approximately 220°C for the (100-y)(25Pd - 75Ag) - (z)CuOx filler metal compositions relative to comparable Ag-CuOx alloys. Likewise, the solidus was found to increase for these alloys, respectively by 185°C and 60°C, respectively for CuOx contents of y = 0 - 1mol% and 4 - 10 mol%. For the (100-y)(50Pd - 50Ag) - (y)CuOx alloys, the solidus increased between 280 - 390°C over a copper oxide compositional range of x = 0 to 8 mol%. It was determined from sessile drop experiments conducted on alumina substrates that in all cases the palladium causes an increase in the wetting angle relative to the corresponding binary braze. Alloy compositions of (100-y)(25Pd - 75Ag) - (y)CuOx displayed increased wetting angles of 5-20° relative to comparable binary compositions. (100-y)(50Pd - 50Ag) - (y)CuOx alloys exhibited an increase in contact angle of 10-60° and compositions containing less than 10 mol% CuOx were not able to wet the substrate. Scanning electron microscopy indicated that the microstructure of the braze consists of discrete CuOx precipitates in an alloyed silver-palladium matrix. In both the binary and ternary filler metal formulations, a reaction layer consisting of CuAlO2 was observed along the interface with the alumina substrate. This reaction product appears to be beneficial in promoting wetting by the remaining braze filler metal. However the formation of this layer is hindered as the concentration of palladium in the filler metal is increased, which appears to be the primary cause of poor wettability in these compositions, as indicated by the substantial amount of porosity found along the braze/substrate interface.« less
NASA Astrophysics Data System (ADS)
Dymond, J. H.; Awan, M. A.; Glen, N. F.; Isdale, J. D.
1991-03-01
Viscosity coefficients measured using a two-coil self-centering falling-body viscometer are reported for toluene and three binary mixtures of toluene + n-hexane at 25, 50, 75, and 100°C at pressures up to 500 MPa. The data for a given composition at different temperatures and pressures are correlated very satisfactorily by a plot of reduced viscosity η * versus log V', where V'= V· V 0(TR)/V0(T) and V 0 represents a characteristic volume. The binary mixture data are well represented by the Grunberg and Nissan equation with a mixing parameter which is pressure dependent but composition and temperature independent.
NASA Astrophysics Data System (ADS)
Sultan, J. S.; Fezea, S. M.; Mousa, F. H.
2018-05-01
A binucleating tetradentate Schiff base ligand, 1,4- di[amino methylene carboxylic] phenylene (H2L) and its forth new binuclear complexes [Co(II), Cu(II), Zn(II) and Cd(II)] were prepared via reaction metal (II) chloride with ligand (H2L) using 2:1 (M:L) in ethanol solvent. The new ligand (H2L) and its complexes were characterized by elemental microanalysis (C.H.N), atomic absorption, chloride content, molar conductance’s magnetic susceptibility, FTIR UV- Vis spectral and, 1H, 13 C- NMR (for H2L). The antibacterial activity with bacteria activity with bacteria, Staphylococcus aureus, Bacillus and Esccherichia Coli were studied.
RUNAWAY DWARF CARBON STARS AS CANDIDATE SUPERNOVA EJECTA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Plant, Kathryn A.; Margon, Bruce; Guhathakurta, Puragra
2016-12-20
The dwarf carbon (dC) star SDSS J112801.67+004034.6 has an unusually high radial velocity, 531 ± 4 km s{sup −1}. We present proper motion and new spectroscopic observations which imply a large Galactic rest frame velocity, 425 ± 9 km s{sup −1}. Several other SDSS dC stars are also inferred to have very high galactocentric velocities, again each based on both high heliocentric radial velocity and also confidently detected proper motions. Extreme velocities and the presence of C {sub 2} bands in the spectra of dwarf stars are both rare. Passage near the Galactic center can accelerate stars to such extreme velocities, but the largemore » orbital angular momentum of SDSS J1128 precludes this explanation. Ejection from a supernova in a binary system or disruption of a binary by other stars are possibilities, particularly as dC stars are thought to obtain their photospheric C {sub 2} via mass transfer from an evolved companion.« less
Geomorphic Flood Area (GFA): a DEM-based tool for flood susceptibility mapping at large scales
NASA Astrophysics Data System (ADS)
Manfreda, S.; Samela, C.; Albano, R.; Sole, A.
2017-12-01
Flood hazard and risk mapping over large areas is a critical issue. Recently, many researchers are trying to achieve a global scale mapping encountering several difficulties, above all the lack of data and implementation costs. In data scarce environments, a preliminary and cost-effective floodplain delineation can be performed using geomorphic methods (e.g., Manfreda et al., 2014). We carried out several years of research on this topic, proposing a morphologic descriptor named Geomorphic Flood Index (GFI) (Samela et al., 2017) and developing a Digital Elevation Model (DEM)-based procedure able to identify flood susceptible areas. The procedure exhibited high accuracy in several test sites in Europe, United States and Africa (Manfreda et al., 2015; Samela et al., 2016, 2017) and has been recently implemented in a QGIS plugin named Geomorphic Flood Area (GFA) - tool. The tool allows to automatically compute the GFI, and turn it into a linear binary classifier capable of detecting flood-prone areas. To train this classifier, an inundation map derived using hydraulic models for a small portion of the basin is required (the minimum is 2% of the river basin's area). In this way, the GFA-tool allows to extend the classification of the flood-prone areas across the entire basin. We are also defining a simplified procedure for the estimation of the river depth, which may be helpful for large-scale analyses to approximatively evaluate the expected flood damages in the surrounding areas. ReferencesManfreda, S., Nardi, F., Samela, C., Grimaldi, S., Taramasso, A. C., Roth, G., & Sole, A. (2014). Investigation on the use of geomorphic approaches for the delineation of flood prone areas. J. Hydrol., 517, 863-876. Manfreda, S., Samela, C., Gioia, A., Consoli, G., Iacobellis, V., Giuzio, L., & Sole, A. (2016). Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models. Nat. Hazards, Vol. 79 (2), pp 735-754. Samela, C., Manfreda, S., Paola, F. D., Giugni, M., Sole, A., & Fiorentino, M. (2016). DEM-Based Approaches for the Delineation of Flood-Prone Areas in an Ungauged Basin in Africa. J. Hydrol. Eng,, 06015010. Samela, C., Troy, T. J., & Manfreda, S. (2017a). Geomorphic classifiers for flood-prone areas delineation for data-scarce environments. Adv. Water Resour., 102, 13-28.
Sitar, Tomasz; Popowicz, Grzegorz M.; Siwanowicz, Igor; Huber, Robert; Holak, Tad A.
2006-01-01
Insulin-like growth factor-binding proteins (IGFBPs) control bioavailability, activity, and distribution of insulin-like growth factor (IGF)1 and -2 through high-affinity IGFBP/IGF complexes. IGF-binding sites are found on N- and C-terminal fragments of IGFBPs, the two conserved domains of IGFBPs. The relative contributions of these domains to IGFBP/IGF complexation has been difficult to analyze, in part, because of the lack of appropriate three-dimensional structures. To analyze the effects of N- and C-terminal domain interactions, we determined several x-ray structures: first, of a ternary complex of N- and C-terminal domain fragments of IGFBP4 and IGF1 and second, of a “hybrid” ternary complex using the C-terminal domain fragment of IGFBP1 instead of IGFBP4. We also solved the binary complex of the N-terminal domains of IGFBP4 and IGF1, again to analyze C- and N-terminal domain interactions by comparison with the ternary complexes. The structures reveal the mechanisms of IGF signaling regulation via IGFBP binding. This finding supports research into the design of IGFBP variants as therapeutic IGF inhibitors for diseases of IGF disregulation. In IGFBP4, residues 1–38 form a rigid disulphide bond ladder-like structure, and the first five N-terminal residues bind to IGF and partially mask IGF residues responsible for the type 1 IGF receptor binding. A high-affinity IGF1-binding site is located in a globular structure between residues 39 and 82. Although the C-terminal domains do not form stable binary complexes with either IGF1 or the N-terminal domain of IGFBP4, in the ternary complex, the C-terminal domain contacts both and contributes to blocking of the IGF1 receptor-binding region of IGF1. PMID:16924115
The 13th order resonance from Navy tracking on a diademe 2 fragment
NASA Technical Reports Server (NTRS)
Wagner, C. A.
1974-01-01
A strong constraint on 13th order (odd degree) terms in the geopotential has been derived from Navy tracking on a DIADEME 2 fragment (1967-14F). This object (perigee height: 580 km, orbit inclination: 38.9 deg) is presently decaying slowly through perfect commensurability with these terms. The resonance forces will increase its inclination by 0.02 deg when the passage is complete by late 1974. The constraint (lumped harmonics), derived by adjustment of a pair of harmonic coefficients to the Navy inclination data (principally) is: 10 to the 9th power (14.8 + or - 0.8, 48.3 + or - 0.7) = 0.023(C,S)13,13 -0.172(C,S)15,13 0.505(C,S)17,13 - 0.884(C,S)19,13 + (C,S)21,13 0.673(C,S)23,13 0.099(C,S)25,13 0.295(C,S)27,13 -0.279(C,S)29,13 0.018(C,S)31,13 + There should be a significant contribution to this result from terms as high as 29th degree. But current geopotential solutions (for 13th order terms) to this degree are about 20% in error when judged by this independent data.
Picosecond solvation dynamics—A potential viewer of DMSO—Water binary mixtures
NASA Astrophysics Data System (ADS)
Banik, Debasis; Kundu, Niloy; Kuchlyan, Jagannath; Roy, Arpita; Banerjee, Chiranjib; Ghosh, Surajit; Sarkar, Nilmoni
2015-02-01
In this work, we have investigated the composition dependent anomalous behavior of dimethyl sulfoxide (DMSO)-water binary mixture by collecting the ultrafast solvent relaxation response around a well known solvation probe Coumarin 480 (C480) by using a femtosecond fluorescence up-conversion spectrometer. Recent molecular dynamics simulations have predicted two anomalous regions of DMSO-water binary mixture. Particularly, these studies encourage us to investigate the anomalies from experimental background. DMSO-water binary mixture has repeatedly given evidences of its dual anomalous nature in front of our systematic investigation through steady-state and time-resolved measurements. We have calculated average solvation times of C480 by two individual well-known methods, among them first one is spectral-reconstruction method and another one is single-wavelength measurement method. The results of both the methods roughly indicate that solvation time of C480 reaches maxima in the mole fraction of DMSO XD = 0.12-0.17 and XD = 0.27-0.35, respectively. Among them, the second region (XD = 0.27-0.35) is very common as most of the thermodynamic properties exhibit deviation in this range. Most probably, the anomalous solvation trend in this region is fully guided by the shear viscosity of the medium. However, the first region is the most interesting one. In this region due to formation of strongly hydrogen bonded 1DMSO:2H2O complexes, hydration around the probe C480 decreases, as a result of which solvation time increases.
Linear chirp phase perturbing approach for finding binary phased codes
NASA Astrophysics Data System (ADS)
Li, Bing C.
2017-05-01
Binary phased codes have many applications in communication and radar systems. These applications require binary phased codes to have low sidelobes in order to reduce interferences and false detection. Barker codes are the ones that satisfy these requirements and they have lowest maximum sidelobes. However, Barker codes have very limited code lengths (equal or less than 13) while many applications including low probability of intercept radar, and spread spectrum communication, require much higher code lengths. The conventional techniques of finding binary phased codes in literatures include exhaust search, neural network, and evolutionary methods, and they all require very expensive computation for large code lengths. Therefore these techniques are limited to find binary phased codes with small code lengths (less than 100). In this paper, by analyzing Barker code, linear chirp, and P3 phases, we propose a new approach to find binary codes. Experiments show that the proposed method is able to find long low sidelobe binary phased codes (code length >500) with reasonable computational cost.
Weinstein, J A; Taylor, S J; Rosenberg, M; DePeters, E J
2016-08-01
Previously, feeding whey protein gels containing polyunsaturated fatty acids (PUFA) reduced their rumen biohydrogenation and increased their concentration in milk fat of Holstein cows. Our objective was to test the efficacy of whey protein isolate (WPI) gels produced in a steam tunnel as a method to alter the fatty acid (FA) composition of the milk lipids. Four primiparous Lamancha goats in midlactation were fed three diets in a 3 × 4 Latin square design. The WPI gels were added to a basal concentrate mix that contained one of three lipid sources: (i) 100% soya bean oil (S) to create (WPI/S), (ii) a 1:1 (wt/wt) mixture of S and linseed (L) oil to create (WPI/SL), or (iii) 100% L to create (WPI/L). Periods were 22 days with the first 10 days used as an adjustment phase followed by a 12-day experimental phase. During the adjustment phase, all goats received a rumen available source of lipid, yellow grease, to provide a baseline for milk FA composition. During the experimental phase, each goat received its assigned WPI. Milk FA concentration of C18:2 n-6 and C18:3 n-3 reached 9.3 and 1.64 g/100 g FA, respectively, when goats were fed WPI/S. Feeding WPI/SL increased the C18:2 n-6 and C18:3 n-3 concentration to 6.22 and 4.36 g/100 g FA, and WPI/L increased C18:2 n-6 and C18:3 n-3 to 3.96 and 6.13 g/100 g FA respectively. The adjusted transfer efficiency (%) of C18:3 n-3 to milk FA decreased significantly as dietary C18:3 n-3 intake increased. Adjusted transfer efficiency for C18:2 n-6 did not change with increasing intake of C18:2 n-6. The WPI gels were effective at reducing rumen biohydrogenation of PUFA; however, we observed a change in the proportion increase of C18:3 n-3 in milk FA suggesting possible regulation of n-3 FA to the lactating caprine mammary gland. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.
11 CFR 100.16 - Independent expenditure (2 U.S.C. 431(17)).
Code of Federal Regulations, 2010 CFR
2010-01-01
....16 Section 100.16 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.16 Independent expenditure (2 U.S.C. 431(17)). (a) The term... expenditure. (c) No expenditure shall be considered independent if the person making the expenditure allows a...
NASA Astrophysics Data System (ADS)
Asadi, Zahra; Nasrollahi, Neda; Karbalaei-Heidari, Hamidreza; Eigner, Vaclav; Dusek, Michal; Mobaraki, Nabiallah; Pournejati, Roya
2017-05-01
Two water-soluble mono-nuclear macrocyclic lanthanum(III) complexes of 2,6-diformyl-4-methylphenol with 1,3-diamino-2-propanol (C1) or 1,3-propylenediamine (C2) were synthesized and characterized by UV-Vis, FT-IR, 13C and 1H NMR spectroscopy and elemental analysis. C1 complex was structurally characterized by single-crystal X-ray diffraction, which revealed that the complex was mononuclear and ten-coordinated. The coordination sites around lanthanum(III) were occupied with a five-dentate ligand, two bidentate nitrates, and one water molecule. The interaction of complexes with DNA was studied in buffered aqueous solution at pH 7.4. UV-Vis absorption spectroscopy, emission spectroscopy, circular dichroism (CD) and viscometric measurements provided clear evidence of the intercalation mechanism of binding. The obtained intrinsic binding constants (Kb) 9.3 × 103 and 1.2 × 103 M- 1 for C1 and C2, respectively confirmed that C1 is better intercalator than C2. The DNA docking studies suggested that the complexes bind with DNA in a groove binding mode with the binding affinity of C1 > C2. Moreover, agarose gel electrophoresis study of the DNA-complex for both compounds revealed that the C1 intercalation cause ethidium bromide replacement in a competitive manner which confirms the suggested mechanism of binding. Finally, the anticancer experiments for the treated cancerous cell lines with both synthesized compounds show that these hydrophilic molecules need a suitable carrier to pass through the hydrophobic nature of cell membrane efficiently.
Lin, Rong-Jyh; Wu, Bin-Nan; Lo, Yi-Ching; An, Li-Mei; Dai, Zen-Kong; Lin, Young-Tso; Tang, Chao-Shun; Chen, Ing-Jun
2006-02-01
KMUP-3 (7-[2-[4-(4-nitrobenzene)piperazinyl]ethyl]-1,3-dimethylxanthine) was investigated in guinea pig tracheal smooth muscle. Intratracheal instillation of tumor necrosis factor (TNF)-alpha (0.01 mg/kg/300 microl) induced bronchoconstriction, increases of lung resistance, and decreases of dynamic lung compliance. Instillation of KMUP-3 (0.5-2.0 mg/kg) reversed this situation. In isolated trachea precontracted with carbachol, KMUP-3 (10-100 microM)-caused relaxations were attenuated by epithelium removal and by pretreatments with an inhibitor of K(+) channel, tetraethylammonium (10 mm); K(ATP) channel, glibenclamide (1 microM); voltage-dependent K(+) channel, 4-aminopyridine (100 microM); Ca(2+)-dependent K(+) channel, charybdotoxin (0.1 microM) or apamin (1 microM); soluble guanylate cyclase (sGC), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1one (ODQ, 1 microM); nitric-oxide (NO) synthase, N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 microM); and adenylate cyclase, SQ 22536 [9-(terahydro-2-furanyl)-9H-purin-6-amine] (100 microM). KMUP-3 (0.01-100 microM) induced increases of cGMP and cAMP in primary culture of tracheal smooth muscle cells (TSMCs). The increase in cGMP by KMUP-3 was reduced by ODQ and L-NAME; the increase in cAMP was reduced by SQ 22536. Western blot analysis indicated that KMUP-3 (1 microM) induced expression of protein kinase A (PKA)(ri) and protein kinase G (PKG)(1alpha 1beta) in TSMCs.SQ 22536 inhibited KMUP-3-induced expression of (PKA)(ri). On the contrary, ODQ inhibited KMUP-3-induced expression of PKG(1alpha 1beta) In epithelium-intact trachea, KMUP-3 increased the NO release. Activation of sGC, NO release, and inhibition of phosphodiesterases in TSMCs by KMUP-3 may result in increases of intracellular cGMP and cAMP, which subsequently activate PKG and PKA, efflux of K(+) ion, and associated reduction in Ca(2+) influx in vitro, indicating the action mechanism to protect against TNF-alpha-induced airway dysfunction in vivo.
Zinc(II)-methimazole complexes: synthesis and reactivity.
Isaia, Francesco; Aragoni, Maria Carla; Arca, Massimiliano; Bettoschi, Alexandre; Caltagirone, Claudia; Castellano, Carlo; Demartin, Francesco; Lippolis, Vito; Pivetta, Tiziana; Valletta, Elisa
2015-06-07
The tetrahedral S-coordinated complex [Zn(MeImHS)4](ClO4)2, synthesised from the reaction of [Zn(ClO4)2] with methimazole (1-methyl-3H-imidazole-2-thione, MeImHS), reacts with triethylamine to yield the homoleptic complex [Zn(MeImS)2] (MeImS = anion methimazole). ESI-MS and MAS (13)C-NMR experiments supported MeImS acting as a (N,S)-chelating ligand. The DFT-optimised structure of [Zn(MeImS)2] is also reported and the main bond lengths compared to those of related Zn-methimazole complexes. The complex [Zn(MeImS)2] reacts under mild conditions with methyl iodide and separates the novel complex [Zn(MeImSMe)2I2] (MeImSMe = S-methylmethimazole). X-ray diffraction analysis of the complex shows a ZnI2N2 core, with the methyl thioethers uncoordinated to zinc. Conversely, the reaction of [Zn(MeImS)2] with hydroiodic acid led to the formation of the complex [Zn(MeImHS)2I2] having a ZnI2S2 core with the neutral methimazole units S-coordinating the metal centre. The Zn-coordinated methimazole can markedly modify the coordination environment when changing from its thione to thionate form and vice versa. The study of the interaction of the drug methimazole with the complex [Zn(MeIm)4](2+) (MeIm = 1-methylimidazole) - as a model for Zn-enzymes containing a N4 donor set from histidine residues - shows that methimazole displaces only one of the coordinated MeIm molecules; the formation constant of the mixed complex [Zn(MeIm)3(MeImHS)](2+) was determined.
Fourier transform C-13 NMR analysis of some free and potassium-ion complexed antibiotics.
NASA Technical Reports Server (NTRS)
Ohnishi, M.; Fedarko, M.-C.; Baldeschwieler, J. D.; Johnson, L. F.
1972-01-01
Fourier transforms of the noise-decoupled, natural abundance C-13 NMR free induction decays of the cyclic antibiotic valinomycin and its potassium-ion complex have been obtained at 25.2 MHz. Comparisons are made with C-13 NMR spectra taken at 22.6 MHz of the cyclic antibiotic nonactin and the synthetic polyether dicyclohexyl-18-crown-6 and their potassium complexes. The results obtained suggest that conformational rearrangements of the molecule as a whole can compete with direct interactions between carbons and the potassium ion in determining C-13 chemical shift differences between the free and complexed species.
NASA Astrophysics Data System (ADS)
Geiculescu, O. E.; DesMarteau, D. D.; Creager, S. E.; Haik, O.; Hirshberg, D.; Shilina, Y.; Zinigrad, E.; Levi, M. D.; Aurbach, D.; Halalay, I. C.
2016-03-01
Ionic liquids (IL's) were proposed for use in Li-ion batteries (LIBs), in order to mitigate some of the well-known drawbacks of LiPF6/mixed organic carbonates solutions. However, their large cations seriously decrease lithium transference numbers and block lithium insertion sites at electrode-electrolyte interfaces, leading to poor LIB rate performance. Deep eutectic electrolytes (DEEs) (which share some of the advantages of ILs but possess only one cation, Li+), were then proposed, in order to overcome the difficulties associated with ILs. We report herein on the preparation, thermal properties (melting, crystallization, and glass transition temperatures), transport properties (specific conductivity and viscosity) and thermal stability of binary DEEs based on mixtures of lithium bis(trifluoromethane)sulfonimide or lithium bis(fluoro)sulfonimide salts with an alkyl sulfonamide solvent. Promise for LIB applications is demonstrated by chronoamperometry on Al current collectors, and cycling behavior of negative and positive electrodes. Residual current densities of 12 and 45 nA cm-2 were observed at 5 V vs. Li/Li+ on aluminum, 1.5 and 16 nA cm-2 at 4.5 V vs. Li/Li+, respectively for LiFSI and LiTFSI based DEEs. Capacities of 220, 130, and 175 mAh· g-1 were observed at low (C/13 or C/10) rates, respectively for petroleum coke, LiMn1/3Ni1/3Co1/3O2 (a.k.a. NMC 111) and LiAl0.05Co0.15Ni0.8O2 (a.k.a. NCA).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ogo, Seiji; Chen, H.; Fish, R.H.
The reactions of a new Cp{sup *}Rh aqua synthon, [Cp{sup *}Rh(H{sub 2}O){sub 3}]{sup 2+} (1), at acidic pH values (2-6) with aniline (2), pyridine (3), and L-phenylalanine (4) have provided interesting chemo- and diastereoselectivities as studied by {sup 1}H NMR, FAB/MS, and single-crystal X-ray crystallography. The reaction of 2 and aqua complex 1, at pH values from 4 to 6, quantitatively provided [Cp{sup *}Rh({eta}{sup 6}-aniline)]{sup 2+} (5); the structure of 5 was unequivocally determined by a single-crystal X-ray analysis, which also showed an approximate 25% {eta}{sup 5} component. Compound 3 reacted with 1, at pH 2-6, to selectively provide [Cp{supmore » *}Rh({eta}{sup 1}-pyridine){sub n} (H{sub 2}O){sub 3-n}]{sup 2+} (n = 1-3) complexes 6a-c as a function of pH. Surprisingly, complex 1 reacted with 4, from pH 4 to 6, to provide only one diastereomer of the known cyclic trimer [(Cp{sup *}Rh)({mu}-{eta}{sup 1}-(OCO):{eta}{sup 2}-(N,OCO)-L-phe nylalanine)]{sub 3}{sup 3+} (7; S{sub C},S{sub C},S{sub C},S{sub Rh},S{sub Rh},S{sub Rh},) an example of a one-step, highly diastereoselective reaction in H{sub 2}O. 8 refs., 4 figs., 2 tabs.« less
NASA Astrophysics Data System (ADS)
Pallagi, A.; Dudás, Cs.; Csendes, Z.; Forgó, P.; Pálinkó, I.; Sipos, P.
2011-05-01
Ca 2+-complexation of D-glucose and D-sorbitol have been investigated with the aid of multinuclear ( 1H, 13C and 43Ca) NMR spectroscopy and ab initio quantum chemical calculations. Formation constants of the forming 1:1 complexes have been estimated from one-dimensional 13C NMR spectra obtained at constant ionic strength (1 M NaCl). Binding sites were identified from 2D 1H- 43Ca NMR spectra. 2D NMR measurements and ab initio calculations indicated that Ca 2+ ions were bound in a tridentate manner via the glycosidic OH, the ethereal oxygen in the ring and the OH on the terminal carbon for the α- and β-anomers of glucose and for sorbitol simultaneous binding of four hydroxide moieties (C1, C2, C4 and C6) was suggested.
Ioanoviciu, Alexandra; Meharenna, Yergalem T.; Poulos, Thomas L.; Ortiz de Montellano, Paul R.
2009-01-01
DevS is one of the two sensing kinases responsible for DevR activation and the subsequent entry of Mycobacterium tuberculosis into dormancy. Full length wild-type DevS forms a stable oxy-ferrous complex. The DevS autooxidation rates are extremely low (half-lives > 24 h) in the presence of cations such as K+, Na+, Mg2+, and Ca2+. At relatively high concentrations (100 µM), Fe3+ mildly increases the autooxidation rate (six-fold increase) while Cu2+ accelerates autooxidation more than 1500-fold. Contrary to expectations, removal of the key hydrogen bond between the iron-coordinated oxygen and Tyr171 in the Y171F mutant provides a protein of comparable stability to autooxidation and similar oxygen dissociation rate. This correlates with our earlier finding that the Y171F mutant and wild-type kinase activities are similarly regulated by the binding of oxygen: namely, the ferrous 5c complex is active whereas the oxy ferrous 6c species is inactive. Our results indicate that DevS is a gas sensor in vivo rather than a redox sensor and that the stability of its ferrous-oxy complex is enhanced by inter-domain interactions. PMID:19463006
1985-02-11
any information, apparatus, product or process disclosed or represents that its use would not S infringe privately-owned rights. S S.i : -- :’.- S’. S...hydrolytic 57 - condensation product of Zr(OC3H7)n at 100*C indi- cates cubic phase structure (top); the same material develops traces of monoclinic...interactions. *. 13 Oak" Alcohol Effect Hydroysis edium Etao - etanol I-Proponel IV Fiur 4. Moeua-egtdstiuincre f oyraoioa etanl an 2-rp o afte 24hsa 0C
NASA Astrophysics Data System (ADS)
Ektarawong, A.; Simak, S. I.; Hultman, L.; Birch, J.; Tasnádi, F.; Wang, F.; Alling, B.
2016-04-01
The elastic properties of alloys between boron suboxide (B6O) and boron carbide (B13C2), denoted by (B6O)1-x(B13C2)x, as well as boron carbide with variable carbon content, ranging from B13C2 to B4C are calculated from first-principles. Furthermore, the mixing thermodynamics of (B6O)1-x(B13C2)x is studied. A superatom-special quasirandom structure approach is used for modeling different atomic configurations, in which effects of configurational disorder between the carbide and suboxide structural units, as well as between boron and carbon atoms within the units, are taken into account. Elastic properties calculations demonstrate that configurational disorder in B13C2, where a part of the C atoms in the CBC chains substitute for B atoms in the B12 icosahedra, drastically increase the Young's and shear modulus, as compared to an atomically ordered state, B12(CBC). These calculated elastic moduli of the disordered state are in excellent agreement with experiments. Configurational disorder between boron and carbon can also explain the experimentally observed almost constant elastic moduli of boron carbide as the carbon content is changed from B4C to B13C2. The elastic moduli of the (B6O)1-x(B13C2)x system are also practically unchanged with composition if boron-carbon disorder is taken into account. By investigating the mixing thermodynamics of the alloys, in which the Gibbs free energy is determined within the mean-field approximation for the configurational entropy, we outline the pseudo-binary phase diagram of (B6O)1-x(B13C2)x. The phase diagram reveals the existence of a miscibility gap at all temperatures up to the melting point. Also, the coexistence of B6O-rich as well as ordered or disordered B13C2-rich domains in the material prepared through equilibrium routes is predicted.
Single trial detection of hand poses in human ECoG using CSP based feature extraction.
Kapeller, C; Schneider, C; Kamada, K; Ogawa, H; Kunii, N; Ortner, R; Pruckl, R; Guger, C
2014-01-01
Decoding brain activity of corresponding highlevel tasks may lead to an independent and intuitively controlled Brain-Computer Interface (BCI). Most of today's BCI research focuses on analyzing the electroencephalogram (EEG) which provides only limited spatial and temporal resolution. Derived electrocorticographic (ECoG) signals allow the investigation of spatially highly focused task-related activation within the high-gamma frequency band, making the discrimination of individual finger movements or complex grasping tasks possible. Common spatial patterns (CSP) are commonly used for BCI systems and provide a powerful tool for feature optimization and dimensionality reduction. This work focused on the discrimination of (i) three complex hand movements, as well as (ii) hand movement and idle state. Two subjects S1 and S2 performed single `open', `peace' and `fist' hand poses in multiple trials. Signals in the high-gamma frequency range between 100 and 500 Hz were spatially filtered based on a CSP algorithm for (i) and (ii). Additionally, a manual feature selection approach was tested for (i). A multi-class linear discriminant analysis (LDA) showed for (i) an error rate of 13.89 % / 7.22 % and 18.42 % / 1.17 % for S1 and S2 using manually / CSP selected features, where for (ii) a two class LDA lead to a classification error of 13.39 % and 2.33 % for S1 and S2, respectively.
Fu, Zhi-Fang; Li, Wen-Xian; Bai, Juan; Bao, Jin-Rong; Cao, Xiao-Fang; Zheng, Yu-Shan
2017-05-01
This article reports a novel category of coating structure SiO 2 @Eu(MABA-Si) luminescence nanoparticles (NPs) consisting of a unique organic shell, composed of perchlorate europium(III) complex, and an inorganic core, composed of silica. The binary complex Eu(MABA-Si) 3 ·(ClO 4 ) 3 ·5H 2 O was synthesized using HOOCC 6 H 4 N(CONH(CH 2 ) 3 Si(OCH 2 CH 3 ) 3 ) 2 (MABA-Si) and was used as a ligand. Furthermore, the as-prepared silica NPs were successfully coated with the -Si(OCH 2 CH 3 ) 3 group of MABA-Si to form Si-O-Si chemical bonds by means of the hydrolyzation of MABA-Si. The binary complexes were characterized by elemental analysis, molar conductivity and coordination titration analysis. The results indicated that the composition of the binary complex was Eu(MABA-Si) 3 ·(ClO 4 ) 3 ·5H 2 O. Coating structure SiO 2 @Eu(MABA-Si) NPs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and infrared (IR) spectra. Based on the SEM and TEM measurements, the diameter of core-SiO 2 particles was ~400 and 600 nm, and the thickness of the cladding layer Eu(MABA-Si) was ~20 nm. In the binary complex Eu(MABA-Si) 3 ·(ClO 4 ) 3 ·5H 2 O, the fluorescence spectra illustrated that the energy of the ligand MABA-Si transferred to the energy level for the excitation state of europium(III) ion. Coating structure SiO 2 @Eu(MABA-Si) NPs exhibited intense red luminescence compared with the binary complex. The fluorescence lifetime and fluorescence quantum efficiency of the binary complex and of the coating structure NPs were also calculated. The way in which the size of core-SiO 2 spheres influences the luminescence was also studied. Moreover, the luminescent mechanisms of the complex were studied and explained. Copyright © 2016 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Vignoli Muniz, Gabriel S.; Incio, Jimmy Llontop; Alves, Odivaldo C.; Krambrock, Klaus; Teixeira, Letícia R.; Louro, Sonia R. W.
2018-01-01
The stability of ternary copper(II) complexes of a heterocyclic ligand, L (L being 2,2‧-bipyridine (bipy) or 1,10-phenanthroline (phen)) and the fluorescent antibacterial agent norfloxacin (NFX) as the second ligand was studied at pH 7.4 and different ionic strengths. Fluorescence quenching upon titration of NFX with the binary complexes allowed to obtain stability constants for NFX binding, Kb, as a function of ionic strength. The Kb values vary by more than two orders of magnitude when buffer concentration varies from 0.5 to 100 mM. It was observed that previously synthesized ternary complexes dissociate in buffer according with the obtained stability constants. This shows that equimolar solutions of NFX and binary complexes are equivalent to solutions of synthesized ternary complexes. The interaction of the ternary copper complexes with anionic SDS (sodium dodecyl sulfate) micelles was studied by fluorescence and electron paramagnetic resonance (EPR). Titration of NFX-loaded SDS micelles with the complexes Cu:L allowed to determine the stability constants inside the micelles. Fluorescence quenching demonstrated that SDS micelles increase the stability constants by factors around 50. EPR spectra gave details of the copper(II) local environment, and demonstrated that the structure of the ternary complexes inside SDS micelles is different from that in buffer. Mononuclear ternary complexes formed inside the micelles, while in buffer most ternary complexes are binuclear. The results show that anionic membrane interfaces increase formation of copper fluoroquinolone complexes, which can influence bioavailability, membrane diffusion, and mechanism of action of the antibiotics.
NASA Astrophysics Data System (ADS)
Kathalikkattil, Amal Cherian; Damodaran, Subin; Bisht, Kamal Kumar; Suresh, Eringathodi
2011-01-01
Four new binary molecular compounds between a flexible exobidentate N-heterocycle and a series of dicarboxylic acids have been synthesized. The N-donor 1,4-bis(imidazol-1-ylmethyl)benzene (bix) was reacted with flexible and rigid dicarboxylic acids viz., cyclohexane-1,4-dicarboxylic acid (H 2chdc), naphthalene-1,4-dicarboxylic acid (H 2npdc) and 1H-pyrazole-3,5-dicarboxylic acid (H 2pzdc), generating four binary molecular complexes. X-ray crystallographic investigation of the molecular adducts revealed the primary intermolecular interactions carboxylic acid⋯amine (via O-H⋯N) as well as carboxylate⋯protonated amine (via N-H +⋯O -) within the binary compounds, generating layered and two-dimensional sheet type H-bonded networks involving secondary weak interactions (C-H⋯O) including the solvent of crystallization. Depending on the differences in p Ka values of the selected base/acid (Δp Ka), diverse H-bonded supramolecular assemblies could be premeditated. This study demonstrates the H-bonding interactions between imidazole/imidazolium cation and carboxylic acid/carboxylate anion in providing sufficient driving force for the directed assembly of binary molecular complexes. In the two-component solid form of hetero synthons involving bix and dicarboxylic acid, only H 2chdc exist as cocrystal with bix, while all the other three compounds crystallized exclusively as salt, in agreement with the Δp Ka values predicted for the formation of salts/cocrystals from the base and acid used in the synthesis of supramolecular solids.
Sun, Enwei; Zhang, Rui; Wu, Fengmin; Cao, Wenwu
2013-03-15
The elastic, piezoelectric, and dielectric properties of [001](c) and [011](c) poled 0.33Pb(In(1/2)Nb(1/2))O(3)-0.38Pb(Mg(1/3)Nb(2/3))O(3)-0.29PbTiO(3) single crystals have been fully characterized at room temperature, and the temperature and frequency dependence of the dielectric susceptibility ε(33) were also measured. The depoling temperature of this crystal is more than 20 °C higher than that of the corresponding binary 0.71Pb(Mg(1/3)Nb(2/3))O(3)-0.29PbTiO(3) system. From the measured P-E hysteresis loops, the coercive fields along [001](c) and [011](c) directions have been determined to be 6.0 kV/cm and 6.6 kV/cm, respectively, which indicate that these domain engineered ternary relaxor-based ferroelectric single crystals are excellent candidates for high-power applications.
VizieR Online Data Catalog: Double stars with wide separations in the AGK3 (Halbwachs+, 2016)
NASA Astrophysics Data System (ADS)
Halbwachs, J. L.; Mayor, M.; Udry, S.
2016-10-01
A large list of common proper motion stars selected from the third Astronomischen Gesellschaft Katalog (AGK3) was monitored with the CORAVEL (for COrrelation RAdial VELocities) spectrovelocimeter, in order to prepare a sample of physical binaries with very wide separations. In paper I,66 stars received special attention, since their radial velocities (RV) seemed to be variable. These stars were monitored over several years in order to derive the elements of their spectroscopic orbits. In addition, 10 of them received accurate RV measurements from the SOPHIE spectrograph of the T193 telescope at the Observatory of Haute-Provence. For deriving the orbital elements of double-lined spectroscopic binaries (SB2s), a new method was applied, which assumed that the RV of blended measurements are linear combinations of the RV of the components. 13 SB2 orbits were thus calculated. The orbital elements were eventually obtained for 52 spectroscopic binaries (SBs), two of them making a triple system. 40 SBs received their first orbit and the orbital elements were improved for 10 others. In addition, 11 SBs were discovered with very long periods for which the orbital parameters were not found. It appeared that HD 153252 has a close companion, which is a candidate brown dwarf with a minimum mass of 50 Jupiter masses. In paper II, 80 wide binaries (WBs) were detected, and 39 optical pairs were identified. Adding CPM stars with separations close enough to be almost certain they are physical, a "bias-controlled" sample of 116 wide binaries was obtained, and used to derive the distribution of separations from 100 to 30,000 au. The distribution obtained doesn't match the log-constant distribution, but is in agreement with the log-normal distribution. The spectroscopic binaries detected among the WB components were used to derive statistical informations about the multiple systems. The close binaries in WBs seem to be similar to those detected in other field stars. As for the WBs, they seem to obey the log-normal distribution of periods. The number of quadruple systems is in agreement with the "no correlation" hypothesis; this indicates that an environment conducive to the formation of WBs doesn't favor the formation of subsystems with periods shorter than 10 years. (9 data files).
Singh, Ajay K; Pandey, O P; Sengupta, S K
2013-09-01
Zn(II) complexes have been synthesized by reacting zinc acetate with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/benzaldehyde/indoline-2,3-dione. All these complexes are soluble in DMF and DMSO; low molar conductance values indicate that they are non electrolytes. Elemental analyses suggest that the complexes have 1:2 metal to ligands stoichiometry of the types [ZnL2(H2O)2](L=monoanionic Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/indoline-2,3-dione) [ZnL2(')(OOCCH3)2(H2O)2](L'=neutral Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde), and they were characterized by IR, (1)H NMR, and (13)C NMR. Particle sizes of synthesized compounds were measured with dynamic light scattering (DLS) analyser which indicates that particle diameter are of the range ca. 100-200nm. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and antifungal activities (Colletotrichum falcatum (C. falcatum), Aspergillus niger (A. niger), Fusarium oxysporium (F. oxysporium) Curvularia pallescence (C. pallescence). The antimicrobial activities have shown that upon complexation the activity increases. Copyright © 2013 Elsevier B.V. All rights reserved.
Similarities between N-acetylcysteine and Glutathione in Binding to Lead(II) Ions
Sisombath, Natalie S.; Jalilehvand, Farideh
2015-01-01
N -acetylcysteine is a natural thiol-containing antioxidant, a precursor for cysteine and glutathione, and a potential detoxifying agent for heavy metal ions. However, previous accounts of the efficiency of N-acetylcysteine (H2NAC) in excretion of lead are few and contradicting. Here we report results on the nature of lead(II) complexes formed with N-acetylcysteine in aqueous solution, which were obtained by combining information from several spectroscopic methods, including 207Pb, 13C and 1H NMR, Pb LIII-edge X-ray absorption, Ultraviolet-visible (UV-vis.) spectroscopy and electro-spray ionization mass spectrometry (ESI-MS). Two series of solutions were used containing CPb(II) = 10 and 100 mM, respectively, varying the H2NAC / Pb(II) mole ratios from 2.1 to 10.0 at pH = 9.1 – 9.4. The coordination environments obtained resemble those previously found for the Pb(II) glutathione system: at a ligand-to-lead mole ratio of 2.1 dimeric or oligomeric Pb(II) N-acetylcysteine complexes are formed, while a tri-thiolate [Pb(NAC)3]4− complex dominates in solutions with H2NAC/Pb(II) mole ratios > 3.0. PMID:26624959
Cataloging the Praesepe Cluster: Identifying Interlopers and Binary Systems
NASA Astrophysics Data System (ADS)
Lucey, Madeline R.; Gosnell, Natalie M.; Mann, Andrew; Douglas, Stephanie
2018-01-01
We present radial velocity measurements from an ongoing survey of the Praesepe open cluster using the WIYN 3.5m Telescope. Our target stars include 229 early-K to mid-M dwarfs with proper motion memberships that have been observed by the repurposed Kepler mission, K2. With this survey, we will provide a well-constrained membership list of the cluster. By removing interloping stars and determining the cluster binary frequency we can avoid systematic errors in our analysis of the K2 findings and more accurately determine exoplanet properties in the Praesepe cluster. Obtaining accurate exoplanet parameters in open clusters allows us to study the temporal dimension of exoplanet parameter space. We find Praesepe to have a mean radial velocity of 34.09 km/s and a velocity dispersion of 1.13 km/s, which is consistent with previous studies. We derive radial velocity membership probabilities for stars with ≥3 radial velocity measurements and compare against published membership probabilities. We also identify radial velocity variables and potential double-lined spectroscopic binaries. We plan to obtain more observations to determine the radial velocity membership of all the stars in our sample, as well as follow up on radial velocity variables to determine binary orbital solutions.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-30
... Organizations; C2 Options Exchange, Incorporated; Order Approving Proposed Rule Change Relating to the Complex...,\\2\\ a proposed rule change to modify C2 Rule 6.13(c), ``Process for Complex Order RFR Auction,'' to... at the start of a Complex Order Auction (``COA''); and (ii) require responses to an RFR message...
Schenten, Véronique; Plançon, Sébastien; Jung, Nicolas; Hann, Justine; Bueb, Jean-Luc; Bréchard, Sabrina; Tschirhart, Eric J; Tolle, Fabrice
2018-01-01
S100A8 and S100A9 are members of the S100 family of cytoplasmic EF-hand Ca 2+ -binding proteins and are abundantly expressed in the cytosol of neutrophils. In addition to their intracellular roles, S100A8/A9 can be secreted in the extracellular environment and are considered as alarmins able to amplify the inflammatory response. The intracellular activity of S100A8/A9 was shown to be regulated by S100A9 phosphorylation, but the importance of this phosphorylation on the extracellular activity of S100A8/A9 has not yet been extensively studied. Our work focuses on the impact of the phosphorylation state of secreted S100A9 on the proinflammatory function of neutrophils. In a first step, we characterized the secretion of S100A8/A9 in different stimulatory conditions and investigated the phosphorylation state of secreted S100A9. Our results on neutrophil-like differentiated HL-60 (dHL-60) cells and purified human neutrophils showed a time-dependent secretion of S100A8/A9 when induced by phorbol 12-myristoyl 13-acetate and this secreted S100A9 was found in a phosphorylated form. Second, we evaluated the impact of this phosphorylation on proinflammatory cytokine expression and secretion in dHL-60 cells. Time course experiments with purified unphosphorylated or phosphorylated S100A8/A9 were performed and the expression and secretion levels of interleukin (IL)-1α, IL-1β, IL-6, tumor necrosis factor alpha, CCL2, CCL3, CCL4, and CXCL8 were measured by real-time PCR and cytometry bead array, respectively. Our results demonstrate that only the phosphorylated form of the complex induces proinflammatory cytokine expression and secretion. For the first time, we provide evidence that S100A8/PhosphoS100A9 is inducing cytokine secretion through toll-like receptor 4 signaling.
Schenten, Véronique; Plançon, Sébastien; Jung, Nicolas; Hann, Justine; Bueb, Jean-Luc; Bréchard, Sabrina; Tschirhart, Eric J.; Tolle, Fabrice
2018-01-01
S100A8 and S100A9 are members of the S100 family of cytoplasmic EF-hand Ca2+-binding proteins and are abundantly expressed in the cytosol of neutrophils. In addition to their intracellular roles, S100A8/A9 can be secreted in the extracellular environment and are considered as alarmins able to amplify the inflammatory response. The intracellular activity of S100A8/A9 was shown to be regulated by S100A9 phosphorylation, but the importance of this phosphorylation on the extracellular activity of S100A8/A9 has not yet been extensively studied. Our work focuses on the impact of the phosphorylation state of secreted S100A9 on the proinflammatory function of neutrophils. In a first step, we characterized the secretion of S100A8/A9 in different stimulatory conditions and investigated the phosphorylation state of secreted S100A9. Our results on neutrophil-like differentiated HL-60 (dHL-60) cells and purified human neutrophils showed a time-dependent secretion of S100A8/A9 when induced by phorbol 12-myristoyl 13-acetate and this secreted S100A9 was found in a phosphorylated form. Second, we evaluated the impact of this phosphorylation on proinflammatory cytokine expression and secretion in dHL-60 cells. Time course experiments with purified unphosphorylated or phosphorylated S100A8/A9 were performed and the expression and secretion levels of interleukin (IL)-1α, IL-1β, IL-6, tumor necrosis factor alpha, CCL2, CCL3, CCL4, and CXCL8 were measured by real-time PCR and cytometry bead array, respectively. Our results demonstrate that only the phosphorylated form of the complex induces proinflammatory cytokine expression and secretion. For the first time, we provide evidence that S100A8/PhosphoS100A9 is inducing cytokine secretion through toll-like receptor 4 signaling. PMID:29593718
NASA Astrophysics Data System (ADS)
Swami, M. B.; Hudge, P. G.; Pawar, V. P.
The dielectric properties of binary mixtures of benzylamine-1,2,6-hexantriol mixtures at different volume fractions of 1,2,6-hexanetriol have been measured using Time Domain Reflectometry (TDR) technique in the frequency range of 10 MHz to 30 GHz. Complex permittivity spectra were fitted using Havriliak-Negami equation. By using least square fit method the dielectric parameters such as static dielectric constant (ɛ0), dielectric constant at high frequency (ɛ∞), relaxation time τ (ps) and relaxation distribution parameter (β) were extracted from complex permittivity spectra at 25∘C. The intramolecular interaction of different molecules has been discussed using the Kirkwood correlation factor, Bruggeman factor. The Kirkwood correlation factor (gf) and effective Kirkwood correlation factor (geff) indicate the dipole ordering of the binary mixtures.
Lee, Woonghee; Stark, Jaime L; Markley, John L
2014-11-01
Peak-picking Of Noe Data Enabled by Restriction Of Shift Assignments-Client Server (PONDEROSA-C/S) builds on the original PONDEROSA software (Lee et al. in Bioinformatics 27:1727-1728. doi: 10.1093/bioinformatics/btr200, 2011) and includes improved features for structure calculation and refinement. PONDEROSA-C/S consists of three programs: Ponderosa Server, Ponderosa Client, and Ponderosa Analyzer. PONDEROSA-C/S takes as input the protein sequence, a list of assigned chemical shifts, and nuclear Overhauser data sets ((13)C- and/or (15)N-NOESY). The output is a set of assigned NOEs and 3D structural models for the protein. Ponderosa Analyzer supports the visualization, validation, and refinement of the results from Ponderosa Server. These tools enable semi-automated NMR-based structure determination of proteins in a rapid and robust fashion. We present examples showing the use of PONDEROSA-C/S in solving structures of four proteins: two that enable comparison with the original PONDEROSA package, and two from the Critical Assessment of automated Structure Determination by NMR (Rosato et al. in Nat Methods 6:625-626. doi: 10.1038/nmeth0909-625 , 2009) competition. The software package can be downloaded freely in binary format from http://pine.nmrfam.wisc.edu/download_packages.html. Registered users of the National Magnetic Resonance Facility at Madison can submit jobs to the PONDEROSA-C/S server at http://ponderosa.nmrfam.wisc.edu, where instructions, tutorials, and instructions can be found. Structures are normally returned within 1-2 days.
Low-energy electron collisions with C{sub 4}H{sub 6} isomers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lopes, A.R.; Bettega, M.H.F.; Lima, M.A.P.
2004-01-01
We report integral, differential, and momentum-transfer cross sections for elastic scattering of low-energy electrons by C{sub 4}H{sub 6} isomers, namely, 1,3-butadiene, 2-butyne, and cyclobutene. We use the Schwinger multichannel method with pseudopotentials [M. H. F. Bettega, L. G. Ferreira, and M. A. P. Lima, Phys. Rev. A 47, 1111 (1993)] at the static-exchange approximation to compute the cross sections for energies from 10 to 60 eV. In particular, we discuss the isomer effect, reported by experimental studies for isomers of C{sub 3}H{sub 4} and C{sub 4}H{sub 6}. We also calculate the total ionization cross section using the binary-encounter-Bethe model formore » 2-butyne and 1,3-butadiene, and estimate the inelastic cross section for these two isomers.« less
Zeolitic Imidazolate Framework-8 Membrane for H2/CO2 Separation: Experimental and Modeling
NASA Astrophysics Data System (ADS)
Lai, L. S.; Yeong, Y. F.; Lau, K. K.; Azmi, M. S.; Chew, T. L.
2018-03-01
In this work, ZIF-8 membrane synthesized through solvent evaporation secondary seeded growth was tested for single gas permeation and binary gases separation of H2 and CO2. Subsequently, a modified mathematical modeling combining the effects of membrane and support layers was applied to represent the gas transport properties of ZIF-8 membrane. Results showed that, the membrane has exhibited H2/CO2 ideal selectivity of 5.83 and separation factor of 3.28 at 100 kPa and 303 K. Besides, the experimental results were fitted well with the simulated results by demonstrating means absolute error (MAE) values ranged from 1.13 % to 3.88 % for single gas permeation and 10.81 % to 21.22 % for binary gases separation. Based on the simulated data, most of the H2 and CO2 gas molecules have transported through the molecular pores of membrane layer, which was up to 70 %. Thus, the gas transport of the gases is mainly dominated by adsorption and diffusion across the membrane.
Cao, Yunyun; Xing, Lei; Zhang, Ting; Liao, Wen-Hsuan
2017-12-01
Little is known about temporal changes in sedimentary organic matter (OM) in the East China Sea (ECS) due to the lack of continuous high-resolution records. In this study, we used a multi-proxy approach to reconstruct sedimentary OM variations over the past 100years from three sediment cores collected from the coastal areas of the ECS. For the three cores, total organic carbon (TOC) normalized concentrations of phytoplankton biomarkers (brassicasterol+dinosterol+alkenones) and a marine archaea biomarker (crenarchaeol) showed gradual increases over the past 100years with a greater increase after the 1980s. These increases are attributed to eutrophic conditions caused by monsoonal variation and intensified human activities in the Yangtze River Basin (YRB) over the past century. Conversely, TOC-normalized concentrations of higher plant biomarker long-chain n-alkanes (∑(C 27 +C 29 +C 31 n-alkanes)) showed no obvious trend over the past 100years. The δ 13 C values of TOC (δ 13 C TOC ), the terrestrial and marine biomarker ratio (TMBR) index, and the branched and isoprenoid tetraether (BIT) index for the three cores record a gradual decrease in the contribution of terrestrial organic matter (TOM) since the 1960s. This decrease is likely linked to enhanced dam construction in the YRB from the 1960s onwards, leading to a reduction in TOM input to the ECS. A three end-member mixing model based on δ 13 C TOC values and the TMBR index was used to further divide sedimentary OM into three factions: marine organic matter (MOM), plant OM, and soil OM. The MOM contribution gradually increased over the past 100years, while the contribution of soil OM gradually decreased over the past 100years with a significant decline during the past 50years. This trend can also be related to intensify dam construction in the middle and upper reaches of the YR since the 1960s. Copyright © 2017 Elsevier B.V. All rights reserved.
The Rotational Spectrum of Singly and Doubly 13C-SUBSTITUTED Dimethylether
NASA Astrophysics Data System (ADS)
Koerber, Monika; Endres, Christian P.; Lewen, Frank; Giesen, Thomas F.; Schlemmer, Stephan; Pohl, Roland; Klein, Axel
2010-06-01
Dimethylether (DME) is a nearly prolate asymmetric top with two internal rotors (methyl groups) which undergo periodic large amplitude motions and show a complicated torsional splitting of each rotational energy level. Due to its complex spectrum and its high abundance in hot cores such as Orion KL or Sagittarius B2 at temperatures exceeding 100 K, DME is very prominent in astronomical line surveys and contributes to spectral line confusion of such sources. The interpretation of astronomical observations therefore depends on the knowledge of accurate rest frequencies and reliable intensities. Precise predictions for the ground state of DME's main isotopologue are now available up to 2.1 THz In contrast, very little is known about 13C-substituted DME. Only a few data are available on singly 13C-substituted DME, 12CH_3O13CH_3. However, no data are available on doubly 13C-substituted DME, (13CH_3)_2O, yet. While in (13CH_3)_2O the two internal rotating methyl groups are equivalent and the splitting of rotational energy levels into four substates is comparable to the main isotopologue, singly 13C-substituted DME has two non-equivalent internal rotors resulting in torsional splitting of rotational energy levels into five substates. The purpose of our new laboratory measurements is to extend the knowledge on the astrophysically relevant species 12CH_3O13CH_3. To analyze the complicated spectrum resulting from a 13C-enriched sample of DME, containing all different 13C-substituted species as well as the main isotopologue, also precise data on doubly 13C-substituted DME are inevitable. We performed measurements in the frequency region 35-120 GHz using an all solid state spectrometer. Rotational as well as torsional parameters have been obtained for (13CH_3)_2O as well as 12CH_3O13CH_3 by fitting the assigned transitions to an effective rotational Hamiltonian introduced by Peter Groner. C. Comito et al., Astrophys. J. Suppl. Ser. 156, 127-167 (2005) C. P. Endres et al., Astronomy & Astrophysics 504, 635-640 (2009) Y. Niide and M. Hayashi, J. Mol. Spectrosc. 220, 65-79 (2003) P. Groner, J. Chem. Phys. 107, 4483-4498 (1997).
Panteva, M.; Varadinova, T.; Turel, I.
1998-01-01
We have found that when copper, zinc or cobalt is bound to a suitable ligand, the appropriate complex exhibited a significant anti-HSV effect (Varadinova et al., 1993; 1996). Recently published data by Sagripanti et al. (1997) also show that the inhibition of HSV by copper was enhanced by reducing agents and that mechanism of the inactivation is similar as for copper-mediated DNA damage (Aruoma, et al. 1991; Dizdaroglu, et al., 1991; Toyokuni and Sagripanti, 1994). Therefore it was interesting to study the efect of Cu(ll) coordination compounds with acyclovir (ACV) on the replication of HSV in cultured cells. The experiments on cytotoxicity as well as on the activity of three different Cu-ACV complexes [Cu(ACV)2Cl2(H2O)2] = (A); [Cu(ACV)2(H2O)3](NO3)2.H2O = (B) and [Cu(ACV)2(H2O)2](NO3)2] = (C) towards virus replication, with special attention on the growth of ACV-resistant strain R-100 were performed on MDBK cells. ACV was used as a reference compound. The following results were obtained: 1) Increased cell’s viability in the presence of 20-40(g/ml ACV and decreased one in the presence of Cu-ACV complexes with relative level (A) >> (B) > (C); 2) Cu-ACV complexes are more cytotoxic than the ligand - ACV and the relative level is (C)>(B)>(A); 3) The anti-HSV effect of ACV can be modulated by copper at levels depending on the specificity of the particular virus strain: (i) for the ACV sensitive strain DA (HSV-1) - ACV ((A) > (C) > (B); (ii) for the ACV sensitive strain Bja (HSV-2) (A) > ACV > (C) > (B); (iii) for strain R-100 (ACVR, TKa) - (A) > ACV > (C) > (B). This findings are consistent with previously published data and undoubtedly show that Cu-ACV complexes could be useful in the treatment of HSV infections, especially when the causative agent is a resistant to ACV mutant. PMID:18475820
Interaction and formation mechanism of binary complex between zein and propylene glycol alginate.
Sun, Cuixia; Dai, Lei; Gao, Yanxiang
2017-02-10
The anti-solvent co-precipitation method was used to fabricate the zein-propylene glycol alginate (PGA) binary complex with different mass ratios of zein to PGA (20:1, 10:1, 5:1, 2:1 and 1:1) at pH 4.0. Results showed that attractive electrostatic interaction between zein and PGA occurred and negatively charged binary complex with large size and high turbidity was formed due to the charge neutralization. Hydrogen bonding and hydrophobic effects were involved in the interactions between zein and PGA, leading to the changed secondary structure and improved thermal stability of zein. Aggregates in the irregular shape with large size were obviously observed in the AFM images. PGA alone exhibited a fine filamentous network structure, while zein-PGA binary complex showed a rough branch-like pattern and the surface of "branch" was closely adsorbed by lots of spherical zein particles. Q in zein-PGA binary complex dispersions presented the improved photochemical and thermal stability. The potential mechanism of a two-step process was proposed to explain the formation of zein-PGA binary complexes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Crystal structures of Mycobacterium tuberculosis GlgE and complexes with non-covalent inhibitors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lindenberger, Jared J.; Kumar Veleti, Sri; Wilson, Brittney N.
GlgE is a bacterial maltosyltransferase that catalyzes the elongation of a cytosolic, branched α-glucan. In Mycobacterium tuberculosis (M. tb), inactivation of GlgE (Mtb GlgE) results in the rapid death of the organism due to a toxic accumulation of the maltosyl donor, maltose-1-phosphate (M1P), suggesting that GlgE is an intriguing target for inhibitor design. In this study, the crystal structures of the Mtb GlgE in a binary complex with maltose and a ternary complex with maltose and a maltosyl-acceptor molecule, maltohexaose, were solved to 3.3 Å and 4.0 Å, respectively. The maltohexaose structure reveals a dominant site for α-glucan binding. Tomore » obtain more detailed interactions between first generation, non-covalent inhibitors and GlgE, a variant Streptomyces coelicolor GlgEI (Sco GlgEI-V279S) was made to better emulate the Mtb GlgE M1P binding site. The structure of Sco GlgEI-V279S complexed with α-maltose-C-phosphonate (MCP), a non-hydrolyzable substrate analogue, was solved to 1.9 Å resolution, and the structure of Sco GlgEI-V279S complexed with 2,5-dideoxy-3-O-α-D-glucopyranosyl-2,5-imino-D-mannitol (DDGIM), an oxocarbenium mimic, was solved to 2.5 Å resolution. These structures detail important interactions that contribute to the inhibitory activity of these compounds, and provide information on future designs that may be exploited to improve upon these first generation GlgE inhibitors.« less
Crystal Phases Formed in a CaO-Fe2O3 System Under a High Cooling Rate in Air
NASA Astrophysics Data System (ADS)
Kashiwaya, Yoshiaki
2017-12-01
A CaO-Fe2O3 system is a fundamental binary system for the iron ore sintering process. Although the basic reactions have been investigated since the 1960s, melting and solidification caused by the combustion of coke results in an unstable state owing to extreme temperature variations. In this study, using a hot thermocouple method, samples of 10 pct CaO-90 pct Fe2O3 and 20 pct CaO-80 pct Fe2O3 were melted on a thermocouple and quenched with several techniques. The obtained samples were precisely examined by XRD. It was found that the sample containing 10 pct CaO-90 pct Fe2O3 changed to 10 pct CaO-13 pct FeO-77 pct Fe2O3 under an oxygen partial pressure ( P_{{{O}2 }} ) of 0.21 during melting. For the 10 pct CaO sample, the crystal phases found at a low cooling rate (509 K/s) were WFss, C4WF8 (C: CaO, W: FeO, F: Fe2O3), and C2W4F9. When the sample composition was 20 pct CaO, the precipitated crystal phases were C4WF4, C4F7, and C4WF8. On the other hand, the crystal phases for high cooling rates (1590 and 7900 K/s) with 10 pct CaO were WFss (solid solution of WF and F), F, and C2W4F9. The formation of the equilibrium phases WFss, F, C4WF4, and C4WF8 can be understood by examining the isothermal section of the phase diagrams, while the unstable phases C2W4F9 and C4F7 are discussed on the basis of the reactions under an equilibrium state.
Buchholz, Jens; Schwentner, Andreas; Brunnenkan, Britta; Gabris, Christina; Grimm, Simon; Gerstmeir, Robert; Takors, Ralf; Eikmanns, Bernhard J; Blombach, Bastian
2013-09-01
Exchange of the native Corynebacterium glutamicum promoter of the aceE gene, encoding the E1p subunit of the pyruvate dehydrogenase complex (PDHC), with mutated dapA promoter variants led to a series of C. glutamicum strains with gradually reduced growth rates and PDHC activities. Upon overexpression of the l-valine biosynthetic genes ilvBNCE, all strains produced l-valine. Among these strains, C. glutamicum aceE A16 (pJC4 ilvBNCE) showed the highest biomass and product yields, and thus it was further improved by additional deletion of the pqo and ppc genes, encoding pyruvate:quinone oxidoreductase and phosphoenolpyruvate carboxylase, respectively. In fed-batch fermentations at high cell densities, C. glutamicum aceE A16 Δpqo Δppc (pJC4 ilvBNCE) produced up to 738 mM (i.e., 86.5 g/liter) l-valine with an overall yield (YP/S) of 0.36 mol per mol of glucose and a volumetric productivity (QP) of 13.6 mM per h [1.6 g/(liter × h)]. Additional inactivation of the transaminase B gene (ilvE) and overexpression of ilvBNCD instead of ilvBNCE transformed the l-valine-producing strain into a 2-ketoisovalerate producer, excreting up to 303 mM (35 g/liter) 2-ketoisovalerate with a YP/S of 0.24 mol per mol of glucose and a QP of 6.9 mM per h [0.8 g/(liter × h)]. The replacement of the aceE promoter by the dapA-A16 promoter in the two C. glutamicum l-lysine producers DM1800 and DM1933 improved the production by 100% and 44%, respectively. These results demonstrate that C. glutamicum strains with reduced PDHC activity are an excellent platform for the production of pyruvate-derived products.
Buchholz, Jens; Schwentner, Andreas; Brunnenkan, Britta; Gabris, Christina; Grimm, Simon; Gerstmeir, Robert; Takors, Ralf; Eikmanns, Bernhard J.
2013-01-01
Exchange of the native Corynebacterium glutamicum promoter of the aceE gene, encoding the E1p subunit of the pyruvate dehydrogenase complex (PDHC), with mutated dapA promoter variants led to a series of C. glutamicum strains with gradually reduced growth rates and PDHC activities. Upon overexpression of the l-valine biosynthetic genes ilvBNCE, all strains produced l-valine. Among these strains, C. glutamicum aceE A16 (pJC4 ilvBNCE) showed the highest biomass and product yields, and thus it was further improved by additional deletion of the pqo and ppc genes, encoding pyruvate:quinone oxidoreductase and phosphoenolpyruvate carboxylase, respectively. In fed-batch fermentations at high cell densities, C. glutamicum aceE A16 Δpqo Δppc (pJC4 ilvBNCE) produced up to 738 mM (i.e., 86.5 g/liter) l-valine with an overall yield (YP/S) of 0.36 mol per mol of glucose and a volumetric productivity (QP) of 13.6 mM per h [1.6 g/(liter × h)]. Additional inactivation of the transaminase B gene (ilvE) and overexpression of ilvBNCD instead of ilvBNCE transformed the l-valine-producing strain into a 2-ketoisovalerate producer, excreting up to 303 mM (35 g/liter) 2-ketoisovalerate with a YP/S of 0.24 mol per mol of glucose and a QP of 6.9 mM per h [0.8 g/(liter × h)]. The replacement of the aceE promoter by the dapA-A16 promoter in the two C. glutamicum l-lysine producers DM1800 and DM1933 improved the production by 100% and 44%, respectively. These results demonstrate that C. glutamicum strains with reduced PDHC activity are an excellent platform for the production of pyruvate-derived products. PMID:23835179
Kwon, Yong Hwan; Kim, Nayoung; Lee, Ju Yup; Choi, Yoon Jin; Yoon, Kichul; Hwang, Jae Jin; Lee, Hyun Joo; Lee, AeRa; Jeong, Yeon Sang; Oh, Sooyeon; Yoon, Hyuk; Shin, Cheol Min; Park, Young Soo; Lee, Dong Ho
2015-06-01
The (13)C-urea breath test ((13)C-UBT) is a noninvasive method for diagnosing Helicobacter pylori (H. pylori) infection. The aims of this study were to evaluate the diagnostic validity of the (13)C-UBT cutoff value and to identify influencing clinical factors responsible for aberrant results. (13)C-UBT (UBiTkit; Otsuka Pharmaceutical, cutoff value: 2.5‰) results in the range 2.0‰ to 10.0‰ after H. pylori eradication therapy were compared with the results of endoscopic biopsy results of the antrum and body. Factors considered to affect test results adversely were analyzed. Among patients with a positive (13)C-UBT result (2.5‰ to 10.0‰, n = 223) or a negative (13)C-UBT result (2.0‰ to < 2.5‰, n = 66) after H. pylori eradication, 73 patients (34.0%) were false positive, and one (1.5%) was false negative as determined by endoscopic biopsy. The sensitivity, specificity, false-positive rate, and false-negative rate for a cutoff value of 2.5‰ were 99.3%, 47.1%, 52.9%, and 0.7%, respectively, and positive and negative predictive values of the (13)C-UBT were 67.3% and 98.5%, respectively. Multivariate analysis showed that a history of two or more previous H. pylori eradication therapies (OR = 2.455, 95%CI = 1.299-4.641) and moderate to severe gastric intestinal metaplasia (OR = 3.359, 95%CI = 1.572-7.178) were associated with a false-positive (13)C-UBT result. The (13)C-UBT cutoff value currently used has poor specificity for confirming H. pylori status after eradication, and this lack of specificity is exacerbated in patients that have undergone multiple prior eradication therapies and in patients with moderate to severe gastric intestinal metaplasia. In addition, the citric-free (13)C-UBT would increase a false-positive (13)C-UBT result. © 2015 John Wiley & Sons Ltd.
Monitoring for PCBs at the Pilot Plant Complex, Aberdeen Proving Ground
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneider, J.F.; O`Neill, H.J.; Cohut, V.J.
1995-07-01
The US Army`s Aberdeen Proving Ground has been a test site for a variety of munitions, including chemical warfare agents. The Pilot Plant Complex (PPC) at Aberdeen was the site of the development, manufacture, storage, and disposal of a number of chemical warfare agents. The objective of this study was to determine if there is polychlorinated biphenyl (PCB) contamination in the PPC. The results of screening done by Argonne indicate that PCBs in the air of the PPC are well below acceptable levels. The total PCB burden of the surfaces in the PPC appears to be well below the 50-ppMmore » regulatory level. However, the study identified contaminated floor surfaces that exceed the acceptable level of 10 {mu}g/100 cm{sup 2} for a workplace. Areas in Building E5618 exceed 1,000 {mu}g/100 cm{sup 2}, with a high reading of 21,100 {mu}g/100 cm{sup 2} in room C103. Building E5625 has several areas where PCBs exceed 100 {mu}g/cm{sup 2}.« less
Garba, Umar; Kaur, Sawinder; Gurumayum, Sushma; Rasane, Prasad
2015-09-01
This study was conducted to investigate the effect of blanching treatment (98 °C for 3 and 6 min) and air drying temperature of 40, 50 and 60 °C on the thin layer drying characteristics such as drying time, drying rate constant, effective moisture diffusivity and activation energy, as well as on anthocyanin content of black carrot shreds. It was observed that drying temperature affected the drying rate but blanching did not have an effect on drying time. Three thin layer drying models, i.e. Page, Lewis and Henderson-Pabis were evaluated. The goodness of these models was evaluated based on the coefficient of determination (R 2 ), root mean square error, reduced chi square (χ 2 ) and standard error. Page model showed the best fit to the drying data. The effective diffusivity ranges of 1.4·10 -9 to 2.6·10 -9 m 2 /s, 1.3·10 -9 to 2.1·10 -9 m 2 /s and 1.5·10 -9 to 2.2·10 -9 m 2 /s after 3 or 6 min of blanching and control samples respectively were calculated using Fick's second law. The activation energy of 37.5, 26.0 and 34.6 kJ/(mol·K) of the control samples and samples blanched for 3 or 6 min respectively was determined from the Arrhenius plot. The blanching treatment affected the anthocyanin content to a great extent. The anthocyanin content of (231.7±2.9) and (278.8±7.8) mg per 100 g was recorded in samples blanched for 3 and 6 min and then dried at 60 °C, and (153.0±4.3) and (247.0±5.5) mg per 100 g was recorded at 40 °C as compared to the control of (580.1±1.3) at 60 °C and (466.7±1.1) mg per 100 g at 40 °C.
NASA Astrophysics Data System (ADS)
EL Hamdani, H.; EL Amane, M.; Duhayon, C.
2018-04-01
The complex 2(C8H10N4O2).[Co(H2O)4(NCS)2].4H2O was prepared in the water-ethanol solution at room temperature and characterized by the single crystal X-ray diffraction analysis, 1H, 13C NMR, TGA/DTA and IR spectroscopy. This complex was crystallized in the monoclinic system (P 21/c). The unit cell parameters are a = 10.65854 (19) A°, b = 8.16642 (14) A°, c = 18.0595 (3) A° with β = 96.4701° (15). The cobalt (II) cation is coordinated by four oxygen atoms of the water molecules and two nitrogen in isothiocyanato a trans octahedral geometry, stabilized by hydrogen bonds with caffeine molecule and free water molecule, The intermolecular hydrogen bonds: Osbnd H⋯N, Osbnd H⋯O, Csbnd H⋯S, π···π interactions are together playing a vital role in the stabilization of the crystal packing.
NASA Astrophysics Data System (ADS)
Qiao, Huimin; He, Chao; Yuan, Feifei; Wang, Zujian; Li, Xiuzhi; Liu, Ying; Guo, Haiyan; Long, Xifa
2018-04-01
The acceptor doped relaxor-based ferroelectric materials are useful for high power applications such as probes in ultrasound-guided high intensity focused ultrasound therapy. In addition, a high Curie temperature is desired because of wider temperature usage and improved temperature stability. Previous investigations have focused on Pb(Mg1/3Nb2/3)O3-PbTiO3 and Pb(Zn1/3Nb2/3)O3-PbTiO3 systems, which have a ultrahigh piezoelectric coefficient and dielectric constant, but a relatively low Curie temperature. It is desirable to study the binary relaxor-based system with a high Curie temperature. Therefore, Pb(In1/2Nb1/2)O3-PbTiO3 (PINT) single crystals were chosen to study the Mn-doped influence on their electrical properties and domain configuration. The evolution of ferroelectric hysteresis loops for doped and virgin samples exhibit the pinning effect in Mn-doped PINT crystals. The relaxation behaviors of doped and virgin samples are studied by fit of the modified Curie-Weiss law and Volgel-Fucher relation. In addition, a short-range correlation length was fitted to study the behavior of polar nanoregions based on the domain configuration obtained by piezoresponse force microscopy. Complex domain structures and smaller short-range correlation lengths (100-150 nm for Mn-doped PINT and >400 nm for pure PINT) were obtained in the Mn-doped PINT single crystals.
Circumstellar Structure Properties of Young Stellar Objects: Envelopes, Bipolar Outflows, and Disks
NASA Astrophysics Data System (ADS)
Kwon, Woojin
2009-12-01
Physical properties of the three main structures in young stellar objects (YSOs), envelopes, bipolar outflows, and circumstellar disks, have been studied using radio interferometers: the Berkeley-Illinois-Maryland Association (BIMA) array and the Combined Array for Research in Millimeter-wave Astronomy (CARMA). (1) Envelopes. Three Class 0 YSOs (L1448 IRS 2, L1448 IRS 3, and L1157) have been observed by CARMA at λ = 1.3 mm and 2.7 mm continuum. Through visibility modeling to fit the two wavelength continuum data simultaneously, we found that the dust opacity spectral index (β) of Class 0 YSOs is around unity, which implies that dust grains have significantly grown already at the earliest stage. In addition, we discussed the radial dependence of β detected in L1448 IRS 3B and also estimated the density distribution of the three targets. (2) Bipolar outflows. Polarimetric observations in the λ = 1.3 mm continuum and CO, as well as spectral line observations in 13CO and C18O have been carried out toward L1448 IRS 3, which has three Class 0 YSOs, using BIMA. We clearly identified two interacting bipolar outflows from the "binary system" of IRS 3A and 3B and estimated the velocity, inclination, and opening angle of the 3B bipolar outflow, using Bayesian inference. Also, we showed that the "binary system" can be bound gravitationally and we estimated the specific angular momentum, which is between those of binary stars and molecular cloud cores. In addition, we marginally detected linear polarizations at the center of IRS 3B (implying a toroidal magnetic field) in continuum and at the bipolar outflow region in CO. (3) Circumstellar disks. We present the results of 6 objects (CI Tau, DL Tau, DO Tau, FT Tau, Haro 6-13, and HL Tau) in our T Tauri disk survey using CARMA. The data consist of λ = 1.3 mm and 2.7 mm continuum with an angular resolution up to 0.13". Through visibility modeling of two disk models (power-law disk with a Gaussian edge and viscous accretion disk) to fit the two wavelength data simultaneously in Bayesian inference, we constrained disk properties. In addition, we detected a dust lane at 100 AU radius of HL Tau, which is gravitationally unstable and can be fragmented. Besides, CI Tau and DL Tau appear to have a spiral pattern. Moreover, we found that more evolved disks have a shallower density gradient and that disks with a smaller β are less massive, which implies "hidden" masses in the cold midplane and/or in large grains. Finally, we found that the accretion disk model is preferred by HL Tau, which has a strong bipolar outflow and accretion, while the power-law disk model is preferred by DL Tau, which has experienced dust settlement and has weak accretion. This implies that the accretion disk model could be applied to disks only in a limited age range.
IGR J14257-6117, a magnetic accreting white dwarf with a very strong strong X-ray orbital modulation
NASA Astrophysics Data System (ADS)
Bernardini, F.; de Martino, D.; Mukai, K.; Falanga, M.
2018-04-01
IGR J14257-6117 is an unclassified source in the hard X-ray catalogues. Optical follow-ups suggest it could be a Cataclysmic Variable of the magnetic type. We present the first high S/N X-ray observation performed by XMM-Newton at 0.3-10 keV, complemented with 10-80 keV coverage by Swift/BAT, aimed at revealing the source nature. We detected for the first time a fast periodic variability at 509.5 s and a longer periodic variability at 4.05 h, ascribed to the white dwarf (WD) spin and binary orbital periods, respectively. These unambiguously identify IGR J14257-6117 as a magnetic CV of the Intermediate Polar (IP) type. The energy resolved light curves at both periods reveal amplitudes decreasing with increasing energy, with the orbital modulation reaching ˜100% in the softest band. The energy spectrum shows optically thin thermal emission with an excess at the iron complex, absorbed by two dense media (NH ˜ 1022 - 23 cm-2), partially covering the X-ray source. These are likely localised in the magnetically confined accretion flow above the WD surface and at the disc rim, producing the energy dependent spin and orbital variabilities, respectively. IGR J14257-6117, joins the group of strongest orbitally modulated IPs now counting four systems. Drawing similarities with low-mass X-ray binaries displaying orbital dips, these IPs should be seen at large orbital inclinations allowing azimuthally extended absorbing material fixed in the binary frame to intercept the line of sight. For IGR J14257-6117, we estimate (50o ≲ i ≲ 70o). Whether also the mass accretion rate plays a role in the large orbital modulations in IPs cannot be established with the present data.
Low-Metallicity Lead Stars: Comparison between Theory and Observations
NASA Astrophysics Data System (ADS)
Bisterzo, S.; Gallino, R.; Straniero, O.; Aoki, W.; Ryan, S.; Beers, T. C.
2006-07-01
We compare AGB theoretical models with spectroscopic abundances of a sample of very metal-poor, C-rich, s-rich and lead-rich stars observed at high-resolution spectroscopy. Fits are obtained for AGB models with different 13C-pocket efficiencies and initial masses. The two intrinsic indicators, [hs/ls] and [Pb/hs] versus [Fe/H], are analyzed. An extended analysis of all the observed elements is made, outlining apparent discrepancies for a few elements. The analysis of C and N abundances strengthen the need of a strong cool bottom process occurring during the AGB. A significant number of these stars are both s-enriched and r-enriched. For them, the envelope abundances are predicted by mass transfer from the more massive AGB companion in a binary system from a parental cloud already enriched in r-elements.
Kolar, Praveen; Kastner, James R
2010-02-01
Poultry rendering emissions contain volatile organic compounds (VOCs) that are nuisance, odorous, and smog and particulate matter precursors. Present treatment options, such as wet scrubbers, do not eliminate a significant fraction of the VOCs emitted including, 2-methylbutanal (2-MB), 3-methylbutanal, and hexanal. This research investigated the low-temperature (25-160 degrees C) catalytic oxidation of 2-MB and hexanal vapors in a differential, plug flow reactor using wood fly ash (WFA) as a catalyst and oxygen and ozone as oxidants. The oxidation rates of 2-MB and hexanal ranged between 3.0 and 3.5 x 10(-9)mol g(-1)s(-1) at 25 degrees C and the activation energies were 2.2 and 1.9 kcal mol(-1), respectively. The catalytic activity of WFA was comparable to other commercially available metal and metal oxide catalysts. We theorize that WFA catalyzed a free radical reaction in which 2-butanone and CO(2) were formed as end products of 2-MB oxidation, while CO(2), pentanal, and butanal were formed as end products of hexanal oxidation. When tested as a binary mixture at 25 and 160 degrees C, no inhibition was observed. Additionally, when ozone was tested as an oxidant at 160 degrees C, 100% removal was achieved within a 2-s reaction time. These results may be used to design catalytic oxidation processes for VOC removal at poultry rendering facilities and potentially replace energy and water intensive air pollution treatment technologies currently in use. Copyright (c) 2009 Elsevier Ltd. All rights reserved.
High Resolution 13C MRI With Hyperpolarized Urea: In Vivo T2 Mapping and 15N Labeling Effects
Reed, Galen D.; von Morze, Cornelius; Bok, Robert; Koelsch, Bertram L.; Van Criekinge, Mark; Smith, Kenneth J.; Shang, Hong; Larson, Peder E. Z.; Kurhanewicz, John; Vigneron, Daniel B.
2014-01-01
13C steady state free precession (SSFP) magnetic resonance imaging and effective spin-spin relaxation time (T2) mapping were performed using hyperpolarized [13C] urea and [13C, 15N2] urea injected intravenously in rats. 15N labeling gave large T2 increases both in solution and in vivo due to the elimination of a strong scalar relaxation pathway. The T2 increase was pronounced in the kidney, with [13C, 15N2] urea giving T2 values of 6.3±1.3 s in the cortex and medulla, and 11±2 s in the renal pelvis. The measured T2 in the aorta was 1.3±0.3 s. [13C] urea showed shortened T2 values in the kidney of 0.23±0.03 s compared to 0.28±0.03 s measured in the aorta. The enhanced T2 of [13C, 15N2] urea was utilized to generate large signal enhancement by SSFP acquisitions with flip angles approaching the fully refocused regime. Projection images at 0.94 mm in-plane resolution were acquired with both urea isotopes, with [13C, 15N2] urea giving a greater than four-fold increase in signal-to-noise ratio [13C] over urea. PMID:24235273
Abu-Basha, E A; Gehring, R; Albwa'neh, S J
2007-04-01
A pharmacokinetic and bioavailability study of spectinomycin was conducted in healthy broiler chickens following administration of a single (50 mg/kg bw) intravenous (i.v.), intramuscular (i.m.) and subcutaneous (s.c.) dose and oral doses of 50 and 100 mg/kg bw. Following i.v. administration, the elimination half-life (t1/2beta), mean residence time (MRT), volume of distribution at steady-state (Vd(ss)), volume of distribution based on the terminal phase (Vd(z)) and total body clearance (ClB) were 1.46+/-1.10 h, 1.61+/-1.05 h, 0.26+/-0.009 L/kg, 0.34 (0.30-0.38) L/kg and 2.68+/-0.017 mL/min/kg respectively. After i.m. and s.c. dosing, the Cmax was 152.76+/-1.08 and 99.77+/-1.04 microg/mL, achieved at 0.25 (0.25-0.50) and 0.25 (0.25-1.00) h, the t1/2beta was 1.65+/-1.07 and 2.03+/-1.06 h and the absolute bioavailability (F) was 136.1% and 128.8% respectively. A significant difference in Cmax (5.13+/-0.10, 14.26+/-1.12 microg/mL), t1/2beta (3.74+/-1.07, 8.93+/-1.13 h) and ClB/F (22.69+/-0.018, 10.14+/-0.018 mL/min/kg) were found between the two oral doses (50 and 100 mg/kg bw respectively), but there were no differences in the tmax [2.00 (2.00-4.00), 2.00 (2.00-2.00) h] and Vd(z)/F [6.95 (6.34-9.06), 7.98 (4.75-10.62) L/kg). The absolute bioavailability (F) of spectinomycin was 11.8% and 26.4% after oral administration of 50 and 100 mg/kg bw respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raston, Paul L., E-mail: paul.raston@adelaide.edu.au; Jäger, Wolfgang
We report the Fourier transform microwave spectra of the a-type J = 1-0 transitions of the binary and ternary CO-(pH{sub 2}){sub 2}, CO-pH{sub 2}-He, CO-HD, and CO-(oD{sub 2}){sub N=1,2} clusters. In addition to the normal isotopologue of CO for all clusters, we observed the transitions of the minor isotopologues, {sup 13}C{sup 16}O, {sup 12}C{sup 18}O, and {sup 13}C{sup 18}O, for CO-(pH{sub 2}){sub 2} and CO-pH{sub 2}-He. All transitions lie within 335 MHz of the experimentally or theoretically predicted values. In comparison to previously reported infrared spectra [Moroni et al., J. Chem. Phys. 122, 094314 (2005)], we are able to tentativelymore » determine the vibrational shift for CO-pH{sub 2}-He, in addition to its b-type J = 1-0 transition frequency. The a-type frequency of CO-pH{sub 2}-He is similar to that of CO-He{sub 2} [Surin et al., Phys. Rev. Lett. 101, 233401 (2008)], suggesting that the pH{sub 2} molecule has a strong localizing effect on the He density. Perturbation theory analysis of CO-oD{sub 2} reveals that it is approximately T-shaped, with an anisotropy of the intermolecular potential amounting to ∼9 cm{sup −1}.« less
Deaton, Joseph C; Young, Ralph H; Lenhard, Jerome R; Rajeswaran, Manju; Huo, Shouquan
2010-10-18
The photophysical properties of tris-cyclometalated iridium(III) complexes have been probed by chemical and geometric variation through the series fac- and mer-Ir(piq)(x)(ppy)(3-x) (x = 1-3; piq = 1-phenylisoquinolinato-N(∧)C(2'), ppy = 2-phenylpyridinato-N(∧)C(2')). The phosphorescent decays were recorded in solution at 295 K and in polymer films from 2 to 295 K. In the heteroleptic complexes, emission occurs based solely on the piq ligand(s), at least by the nanosecond time scale, as its excited states are the lowest energy. Because fac-Ir(piq)(3) and fac-Ir(ppy)(3) possess practically the same oxidation potential, comparison of photophysical properties through the series fac-Ir(piq)(x)(ppy)(3-x) (x = 1-3) revealed the effects of having one, two, or three emissive piq ligands with no confounding effects from differences in electron withdrawing or donating properties between the spectator ppy ligands and the piq ligands. Effects of placement of piq ligands in different coordination geometries were elucidated by comparisons to the mer series.
NASA Astrophysics Data System (ADS)
Mosa, J.; Durán, A.; Aparicio, M.
An important research area in proton exchange membrane fuel cells (PEMFC) is devoted to the development of low cost membranes able to work at temperatures higher than 100 °C. In this work, homogeneous, transparent and crack-free hybrid membranes have been synthesized using tetraethyl orthosilicate (TEOS), 3-glycidoxipropyl trimethoxysilane (GPTMS) and 2-allylphenol (AP) as precursors. The synthesis of proton conducting membranes was performed by a post-sulfonation method using trimethylsilyl chlorosulfonate as a mild sulfonating agent. The water retention properties provided by sulfonate and hydroxyl groups and the high porosity leads to relatively high proton conductivity (maximum values around 1.3 × 10 -3 S cm -1 at 140 °C and 100% RH) for membranes treated at 180 °C and sulfonated for 2 h.
Applegate, Jason C.; Okeowo, Monisola K.; Erickson, Nathan R.; Neal, Brad M.
2015-01-01
Mercapto (-SH) and isocyano (-N≡C) terminated conducting π-linkers are often employed in the ever-growing quest for organoelectronic materials. While such systems typically involve symmetric dimercapto or diisocyano anchoring of the organic bridge, this article introduces the chemistry of a linear azulenic π-linker equipped with one mercapto and one isocyano terminus. The 2-isocyano-6-mercaptoazulene platform was efficiently accessed from 2-amino-6-bromo-1,3-diethoxycarbonylazulene in four steps. The 2-N≡C end of this 2,6-azulenic motif was anchrored to the [Cr(CO)5] fragment prior to formation of its 6-SH terminus. Metalation of the 6-SH end of [(OC)5Cr(η1-2-isocyano-1,3-diethoxycarbonyl-6-mercaptoazulene)] (7) with Ph3PAuCl, under basic conditions, afforded X-ray structurally characterized heterobimetallic Cr0/AuI ensemble [(OC)5Cr(μ-η1:η1-2-isocyano-1,3-diethoxycarbonyl-6-azulenylthiolate)AuPPh3] (8). Analysis of the 13C NMR chemical shifts for the [(NC)Cr(CO)5] core in a series of the related complexes [(OC)5Cr(2-isocyano-6-X-1,3-diethoxy-carbonylazulene)] (X = -N≡C, Br,H, SH, SCH2CH2CO2CH2CH3, SAuPPh3) unveiled remarkably consistent inverse-linear correlations δ(13COtrans) vs. δ(13CN) and δ(13COcis) vs. δ(13CN) that appear to hold well beyond the above 2-isocyanoazulenic series to include complexes [(OC)5Cr(CNR)] containing strongly electron-withdrawing substituents R, such as CF3, CFClCF2Cl, C2F3, and C6F5. In addition to functioning as asensitive 13C NMR handle, the essentially C4v-symmetric [(-NC)Cr(CO)5] moiety proved to be an informative, remote, νN≡C/νC≡O infrared reporter in probing chemisorption of 7 on the Au(111) surface. PMID:26877864
Highly Reactive Scandium Phosphinoalkylidene Complex: C-H and H-H Bonds Activation.
Mao, Weiqing; Xiang, Li; Alvarez Lamsfus, Carlos; Maron, Laurent; Leng, Xuebing; Chen, Yaofeng
2017-01-25
The first scandium phosphinoalkylidene complex was synthesized and structurally characterized. The complex has the shortest Sc-C bond lengths reported to date (2.089(3) Å). DFT calculations reveal the presence of a three center π interaction in the complex. This scandium phosphinoalkylidene complex undergoes intermolecular C-H bond activation of pyridine, 4-dimethylamino pyridine and 1,3-dimethylpyrazole at room temperature. Furthermore, the complex rapidly activates H 2 under mild conditions. DFT calculations also demonstrate that the C-H activation of 1,3-dimethylpyrazole is selective for thermodynamic reasons and the relatively slow reaction is due to the need of fully breaking the chelating effect of the phosphino group to undergo the reaction whereas this is not the case for H 2 .
A contact binary asteroid evolutionary cycle driven by BYORP & the classical Laplace plane
NASA Astrophysics Data System (ADS)
Rieger, Samantha; Scheeres, Daniel J.
2017-10-01
Several contact binaries have been observed to have high obliquities distributed around 90°. With this information, we explore the possibility of these high obliquities being a key characteristic that causes an evolutionary cycle of contact binary formation and separation.The contact binary cycle begins with a single asteroid that is spinning up due to the YORP effect. For the binary cycle we assume YORP will drive the obliquity to 90°. Eventually, the asteroid will reach a critical spin frequency that will cause the asteroid to fission into a binary. We assume that the mass-ratio, q, of the system is greater than 0.2. With a high q, the secondary will not escape/impact the primary but will evolve through tides into a stable circular double-synchronous orbit. The binary being synchronous will cause the forces from BYORP to have secular effects on the system. For this cycle, BYORP will need to expand the secondary away from the primary.As the system expands, we have found that the secondary will follow the classical Laplace plane. Therefore, the secondary’s orbit will increase in inclination with respect to the equator as the secondary’s orbit expands. The Laplace plane is a stable orbit to perturbations from J2 & Sun tides except for an instability region that exists for primaries with obliquities above 68.875° & a secondary orbital radius of 13.5-19.5 primary radii. Once BYORP expands the secondary into this instability region, the eccentricity of the secondary’s orbit will increase until the orbit intersects with the primary & causes an impact. This impact will create a contact binary with a new obliquity that will randomly range from 23°-150°. The cycle will begin again with YORP driving the contact binary to an obliquity of 90°.Our contribution will discuss the proposed contact binary cycle in more detail, including the mechanics of the system that drives the events given above. We will include investigations into how losing synchronous lock will disrupt the eccentricity growth in the Laplace plane instability region. We will also discuss the time scales of each event to help predict which part of the cycle we will most likely to be observing when discovering new contact binaries & binary systems.
Effects of the η(5)-C5H4(i)Pr Ligand on the Properties Exhibited by Its Tungsten Nitrosyl Complexes.
Fabulyak, Diana; Baillie, Rhett A; Patrick, Brian O; Legzdins, Peter; Rosenfeld, Devon C
2016-02-15
Reaction of Na[η(5)-C5H4(i)Pr] with W(CO)6 in refluxing THF for 4 days generates a solution of Na[(η(5)-C5H4(i)Pr)W(CO)3] that when treated with N-methyl-N-nitroso-p-toluenesulfonamide at ambient temperatures affords (η(5)-C5H4(i)Pr)W(NO)(CO)2 (1) that is isolable in good yield as an analytically pure orange oil. Treatment of 1 with an equimolar amount of I2 in Et2O at ambient temperatures affords (η(5)-C5H4(i)Pr)W(NO)I2 (2) as a dark brown solid in excellent yield. Sequential treatment at low temperatures of 2 with 0.5 equiv of Mg(CH2CMe3)2 and Mg(CH2CH═CMe2)2 in Et2O produces the alkyl allyl complex, (η(5)-C5H4(i)Pr)W(NO)(CH2CMe3)(η(3)-CH2CHCMe2) (3), as a thermally sensitive yellow liquid. Complex 3 may also be synthesized, albeit in low yield, in one vessel at low temperatures by reacting 1 first with 1 equiv of PCl5 and then with the binary magnesium reagents specified above. Interestingly, similar treatment of 1 in Et2O with PCl5 and only 0.5 equiv of Mg(CH2CH═CMe2)2 results in the formation of the unusual complex (η(5)-C5H4(i)Pr)W(NO)(PCl2CMe2CH═CH2)Cl2 (4), which probably is formed via a metathesis reaction of the binary magnesium reagent with (η(5)-C5H4(i)Pr)W(NO)(PCl3)Cl2. The C-D activation of C6D6 by complex 3 has been investigated and compared to that exhibited by its η(5)-C5Me5, η(5)-C5Me4H, and η(5)-C5Me4(n)Pr analogues. Kinetic analyses of the various activations have established that the presence of the η(5)-C5H4(i)Pr ligand significantly increases the rate of the reaction, an outcome that can be attributed to a combination of steric and electronic factors. In addition, mechanistic studies have established that in solution 3 loses neopentane under ambient conditions to generate exclusively the 16e η(2)-diene intermediate complex (η(5)-C5H4(i)Pr)W(NO)(η(2)-CH2═CMeCH═CH2), which then effects the subsequent C-D activations. This behavior contrasts with that exhibited by the η(5)-C5Me5 analogue of 3 which forms both η(2)-diene and η(2)-allene intermediates upon thermolysis. Sixteen-electron (η(5)-C5H4(i)Pr)W(NO)(η(2)-CH2═CMeCH═CH2) has been isolated as its 18e PMe3 adduct. All new organometallic complexes have been characterized by conventional spectroscopic and analytical methods, and the solid-state molecular structures of two of them have been established by single-crystal X-ray crystallographic analyses.
Miscibility of amorphous ZrO2-Al2O3 binary alloy
NASA Astrophysics Data System (ADS)
Zhao, C.; Richard, O.; Bender, H.; Caymax, M.; De Gendt, S.; Heyns, M.; Young, E.; Roebben, G.; Van Der Biest, O.; Haukka, S.
2002-04-01
Miscibility is a key factor for maintaining the homogeneity of the amorphous structure in a ZrO2-Al2O3 binary alloy high-k dielectric layer. In the present work, a ZrO2/Al2O3 laminate thin layer has been prepared by atomic layer chemical vapor deposition on a Si (100) wafer. This layer, with artificially induced inhomogeneity (lamination), enables one to study the change in homogeneity of the amorphous phase in the ZrO2/Al2O3 system during annealing. High temperature grazing incidence x-ray diffraction (HT-XRD) was used to investigate the change in intensity of the constructive interference peak of the x-ray beams which are reflected from the interfaces of ZrO2/Al2O3 laminae. The HT-XRD spectra show that the intensity of the peak decreases with an increase in the anneal temperature, and at 800 °C, the peak disappears. The same samples were annealed by a rapid thermal process (RTP) at temperatures between 700 and 1000 °C for 60 s. Room temperature XRD of the RTP annealed samples shows a similar decrease in peak intensity. Transmission electronic microscope images confirm that the laminate structure is destroyed by RTP anneals and, just below the crystallization onset temperature, a homogeneous amorphous ZrAlxOy phase forms. The results demonstrate that the two artificially separated phases, ZrO2 and Al2O3 laminae, tend to mix into a homogeneous amorphous phase before crystallization. This observation indicates that the thermal stability of ZrO2-Al2O3 amorphous phase is suitable for high-k applications.
LIGO GW150914 and GW151226 gravitational wave detection and generalized gravitation theory (MOG)
NASA Astrophysics Data System (ADS)
Moffat, J. W.
2016-12-01
The nature of gravitational waves in a generalized gravitation theory is investigated. The linearized field equations and the metric tensor quadrupole moment power and the decrease in radius of an inspiralling binary system of two compact objects are derived. The generalized Kerr metric describing a spinning black hole is determined by its mass M and the spin parameter a = cS / GM2. The LIGO-Virgo collaboration data is fitted with smaller binary black hole masses in agreement with the current electromagnetic, observed X-ray binary upper bound for a black hole mass, M ≲ 10M⊙.
Bak, J H; Yoo, B
2018-05-01
The intrinsic viscosity ([η]) values of binary gum mixtures with xanthan gum (XG) and guar gum (GG) mixed with NaCl and sucrose at different concentrations as well as in the presence of different pH levels were examined in dilute solution as a function of XG/GG mixing ratio (100/0, 75/25, 50/50, and 0/100). Experimental values of concentration (C) and relative viscosity (η rel ) or specific viscosity (η sp ) of gums in dilute solution were fitted to five models to determine [η] values of binary gum mixtures including individual gums. A [η] model (η rel =1+[η]C) of Tanglertpaibul and Rao is recommended as the best model to estimate [η] values for the binary gum mixtures with XG and GG as affected by NaCl, sucrose, and pH. Overall, the synergistic interaction of XG-GG mixtures in the presence of NaCl and sucrose showed a greatly positive variation between measured and calculated values of [η]. In contrast, the binary gum mixtures showed synergy only under an acidic condition (pH3). These results suggest that the NaCl and sucrose addition or acidic condition appears to affect the intermolecular interaction occurred between XG and GG at different gum mixing ratios. Copyright © 2018 Elsevier B.V. All rights reserved.
Validation of an enzyme-linked immunosorbent assay (ELISA) for the measurement of canine S100A12.
Heilmann, Romy M; Cranford, Shannon M; Ambrus, Andy; Grützner, Niels; Schellenberg, Stefan; Ruaux, Craig G; Suchodolski, Jan S; Steiner, Jörg M
2016-03-01
Canine S100 calcium-binding protein A12 (cS100A12) shows promise as biomarker of inflammation in dogs. A previously developed cS100A12-radioimmunoassay (RIA) requires radioactive tracers and is not sensitive enough for fecal cS100A12 concentrations in 79% of tested healthy dogs. An ELISA assay may be more sensitive than RIA and does not require radioactive tracers. The purpose of the study was to establish a sandwich ELISA for serum and fecal cS100A12, and to establish reference intervals (RI) for normal healthy canine serum and feces. Polyclonal rabbit anti-cS100A12 antibodies were generated and tested by Western blotting and immunohistochemistry. A sandwich ELISA was developed and validated, including accuracy and precision, and agreement with cS100A12-RIA. The RI, stability, and biologic variation in fecal cS100A12, and the effect of corticosteroids on serum cS100A12 were evaluated. Lower detection limits were 5 μg/L (serum) and 1 ng/g (fecal), respectively. Intra- and inter-assay coefficients of variation were ≤ 4.4% and ≤ 10.9%, respectively. Observed-to-expected ratios for linearity and spiking recovery were 98.2 ± 9.8% (mean ± SD) and 93.0 ± 6.1%, respectively. There was a significant bias between the ELISA and the RIA. The RI was 49-320 μg/L for serum and 2-484 ng/g for fecal cS100A12. Fecal cS100A12 was stable for 7 days at 23, 4, -20, and -80°C; biologic variation was negligible but variation within one fecal sample was significant. Corticosteroid treatment had no clinically significant effect on serum cS100A12 concentrations. The cS100A12-ELISA is a precise and accurate assay for serum and fecal cS100A12 in dogs. © 2016 American Society for Veterinary Clinical Pathology.
Molecular Mechanisms of RNA-Targeting by Cas13-containing Type VI CRISPR-Cas Systems.
O'Connell, Mitchell
2018-06-22
Prokaryotic adaptive immune systems use CRISPRs (Clustered Regularly Interspaced Short Palindromic Repeats) and CRISPR associated (Cas) proteins for RNA-guided cleavage of foreign genetic elements. The focus of this review, Type VI CRISPR-Cas systems, include a single protein known as Cas13 (formerly C2c2), that when assembled with a crRNA forms a crRNA-guided RNA-targeting effector complex. Type VI CRISPR-Cas systems can be divided into four subtypes (A-D) based on Cas13 phylogeny. All Cas13 proteins studied to date possess two enzymatically distinct ribonuclease activities that are required for optimal interference. One RNase is responsible for pre-crRNA processing to form mature Type VI interference complexes, while the other RNase activity provided by the two HEPN (Higher Eukaryotes and Prokaryotes Nucleotide-binding) domains, is required for degradation of target RNA during viral interference. In this review, I will compare and contrast what is known about the molecular architecture and behavior of Type VI (A-D) CRISPR-Cas13 interference complexes, how this allows them to carry out their RNA-targeting function, how Type VI accessory proteins are able to modulate Cas13 activity, and how together all of these features have led to the rapid development of a range of RNA-targeting applications. Throughout I will also discuss some of the outstanding questions regarding Cas13's molecular behavior, and its role in bacterial adaptive immunity and RNA-targeting applications. Copyright © 2018. Published by Elsevier Ltd.
Molecular And Structural Basis of Cytokine Receptor Pleiotropy in the Interleukin-4/13 System
DOE Office of Scientific and Technical Information (OSTI.GOV)
LaPorte, S.L.; Juo, Z.S.; Vaclavikova, J.
2009-05-20
Interleukin-4 and Interleukin-13 are cytokines critical to the development of T cell-mediated humoral immune responses, which are associated with allergy and asthma, and exert their actions through three different combinations of shared receptors. Here we present the crystal structures of the complete set of type I (IL-4R{alpha}/{gamma}{sub c}/IL-4) and type II (IL-4R/IL-13R{alpha}1/IL-4, IL-4R{alpha}/IL-13R{alpha}1/IL-13) ternary signaling complexes. The type I complex reveals a structural basis for {gamma}{sub c}'s ability to recognize six different {gamma}{sub c}-cytokines. The two type II complexes utilize an unusual top-mounted Ig-like domain on IL-13R{alpha}1 for a novel mode of cytokine engagement that contributes to a reversal inmore » the IL-4 versus IL-13 ternary complex assembly sequences, which are mediated through substantially different recognition chemistries. We also show that the type II receptor heterodimer signals with different potencies in response to IL-4 versus IL-13 and suggest that the extracellular cytokine-receptor interactions are modulating intracellular membrane-proximal signaling events.« less
Dinuclear Nickel(II) Complexes as Models for the Active Site of Urease.
Volkmer, Dirk; Hommerich, Birgit; Griesar, Klaus; Haase, Wolfgang; Krebs, Bernt
1996-06-19
Dinuclear nickel(II) complexes of the ligands 2,6-bis[bis((2-benzimidazolylmethyl)amino)methyl]-p-cresol (bbapOH), N,N,N',N'-tetrakis(2-benzimidazolylmethyl)-2-hydroxy-1,3-diaminopropane (tbpOH), N-methyl-N,N',N'-tris(2-benzimidazolylmethyl)-2-hydroxy-1,3-diaminopropane (m-tbpOH) and 1-[N,N-bis(2-benzimidazolylmethyl)amino]-3-[2-(3,5-dimethyl-1H-pyrazol-1-yl)ethoxy]-2-hydroxypropane (bpepOH) were prepared in order to model the active site of urease. The novel asymmetric structures of the dinuclear complexes were characterized by X-ray structure analysis. The complex [Ni(2)(bbapO)(ClO(4))(H(2)O)(MeOH)](ClO(4))(2).Et(2)O, 1, crystallizes in the monoclinic space group P2(1)/c, with a = 10.258(2) Å, b = 19.876(3) Å, c = 25.592(4) Å, and beta = 97.12(2) degrees. The nickel ions in 1 are bridged by the phenoxy donor of the ligand and a perchlorate anion. The complexes [Ni(2)(tbpO)(MeCOO)(H(2)O)](ClO(4))(2).H(2)O.Et(2)O, 2, [Ni(2)(m-tbpO)(PhCOO)(EtOH)(2)](ClO(4))(2).EtOH, 3, and [Ni(2)(bpepO)(MeCOO)(H(2)O)(2)](ClO(4))(2).H(2)O.Et(2)O.2EtOH, 4, also crystallize in the monoclinic crystal system with the following unit cell parameters: 2, C2/c, a = 35.360(13) Å, b = 10.958(3) Å, c = 24.821(10) Å, beta = 103.55(3) degrees; 3, Cc, a = 14.663(5) Å, b = 32.630(13) Å, c = 9.839(3) Å, beta = 92.49(2) degrees; 4, C2/c, a = 27.689(13) Å, b = 12.187(5) Å, c = 31.513(14) Å, beta = 115.01(3) degrees. The dinuclear centers of all these complexes are bridged by the alkoxy donor of the ligand and a carboxylate function. Compounds 2 and 3 have one of the nickel ions in a five-coordinated, trigonal bipyramidal coordination environment and thus show a high structural similarity to the dinuclear active site of urease from Klebsiella aerogenes. Furthermore, their magnetic and spectroscopic properties were determined and related to those of the urease enzymes. Activity toward hydrolysis of test substrates (4-nitrophenyl)urea, 4-nitroacetanilide, 4-nitrophenyl phosphate or bis(4-nitrophenyl) phosphate by the dinuclear complexes were examined by UV spectroscopic measurements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bai, Ying; Li, Yu; Wu, Chuan
Nanoscale Li-rich Li1.2Mn0.54Ni0.13Co0.13O2 material is synthesized by a co-precipitation combined freeze drying (CP-FD) method, and compared with a conventional co-precipitation method combined vacuum drying (CP-VD). With the combination of X-ray diffraction (XRD) and scanning electron microscopy (SEM), it is found that the sample from CP-FD method consists of a pure phase with good crystallinity and small, homogenous particles (100-300 nm) with uniform particle size distribution. Inductively coupled plasma spectroscopy (ICP) shows that the sample has a stoichiometric ratio of n((Li)): n((Mn)): n((Ni)): n((Co))=9: 4: 1: 1; and its Brunauer-Emmett-Teller (BET) specific surface area is 5.749 m(2)g(-1). This sample achieves excellentmore » electrochemical properties: its initial discharge capacities are 298.9 mAhg(-1) at 0.1C (20 mAg(-1)), 246.1 mAhg(-1) at 0.5C, 215.8 mAhg(-1) at 1C, and 154.2 mAhg(-1) at 5C (5C charge and 5C discharge), as well as good cycling performance. In addition, the Li+ chemical diffusion coefficient of Li1.2Mn0.54Ni0.13Co0.13O2 material prepared by the CP-FD method is 4.59 x 10(-11) cm(2) s(-1), which is higher than that of the Li1.2Mn0.54Ni0.13Co0.13O2 material prepared by CP-VD. This phenomenon illustrates the potential for Li1.2Mn0.54Ni0.13Co0.13O2 with good rate performance synthesized by CP-FD method.« less
Sicilia, Violeta; Borja, Pilar; Baya, Miguel; Casas, José M
2015-04-21
The platinum(ii) half-lantern dinuclear complexes [{Pt(bzq)(μ-C7H4NS2-κN,S)}2] () and [{Pt(bzq)(μ-C7H4NOS-κN,S)}2] () [bzq = benzo[h]quinolinate, C7H4NS2 = 2-mercaptobenzothiazolate, C7H4NOS = 2-mercaptobenzoxazolate] in solution of DMSO-H2O undergo a dramatic color change from yellowish-orange to purple and turn-off phosphorescence in the presence of a small amount of Hg(2+), being discernible by the naked-eye and by spectroscopic methods. Other metal ions as Ag(+), Li(+), Na(+), K(+), Ca(2+), Mg(2+), Ba(2+), Pb(2+), Cd(2+), Zn(2+) and Tl(+) were tested and, even in a big excess, showed no interference in the selective detection of Hg(2+) in water. Job's plot analysis indicated a 1 : 1 stoichiometry in the complexation mode of Hg(2+) by /. The phosphorescence quenching attributed to the formation of [/ : Hg(2+)] complexes showed binding constants of K = 1.13 × 10(5) M(-1) () and K = 1.99 × 10(4) M(-1) (). The limit of detection has been also evaluated. In addition, dried paper test strips impregnated in DMSO solutions of and can detect concentration of Hg(2+) in water as low as 1 × 10(-5) M for and 5 × 10(-5) M for , making these complexes good candidates to be used as real-time Hg(2+) detectors. The nature of the interaction of the Pt2 half-lantern complex with the Hg(2+) cation, has been investigated by theoretical calculations.
Adam, J.; Adamová, D.; Aggarwal, M. M.; ...
2016-03-14
The production of prompt charmed mesons D 0, D + and D* +, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at the centre-of-mass energy per nucleon pair, √ sNN, of 2.76 TeV. The production yields for rapidity |y| < 0.5 are presented as a function of transverse momentum, p T, in the interval 1–36 GeV/c for the centrality class 0–10% and in the interval 1–16 GeV/c for the centrality class 30–50%. The nuclear modification factor R AA was computed using a proton-proton reference at √s = 2.76 TeV, based on measurements at √s = 7more » TeV and on theoretical calculations. A maximum suppression by a factor of 5-6 with respect to binary-scaled pp yields is observed for the most central collisions at p T of about 10 GeV/c. A suppression by a factor of about 2-3 persists at the highest p T covered by the measurements. At low pT (1-3 GeV/c), the R AA has large uncertainties that span the range 0.35 (factor of about 3 suppression) to 1 (no suppression). In all p T intervals, the R AA is larger in the 30-50% centrality class compared to central collisions. Furthermore, the D-meson R AA is also compared with that of charged pions and, at large p T, charged hadrons, and with model calculations.« less
Transverse momentum dependence of D-meson production in Pb-Pb collisions at sqrt{{s}_{NN}}=2.76 TeV
NASA Astrophysics Data System (ADS)
Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahn, S. U.; Aiola, S.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Almaraz, J. R. M.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Anielski, J.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Arnaldi, R.; Arnold, O. W.; Arsene, I. C.; Arslandok, M.; Audurier, B.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Barth, K.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Belyaev, V.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biswas, R.; Biswas, S.; Bjelogrlic, S.; Blair, J. T.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botta, E.; Böttger, S.; Bourjau, C.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Butt, J. B.; Buxton, J. T.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Carnesecchi, F.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Ceballos Sanchez, C.; Cepila, J.; Cerello, P.; Cerkala, J.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Cho, S.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; De, S.; De Caro, A.; de Cataldo, G.; de Conti, C.; de Cuveland, J.; De Falco, A.; De Gruttola, D.; De Marco, N.; De Pasquale, S.; Deisting, A.; Deloff, A.; Dénes, E.; Deplano, C.; Dhankher, P.; Di Bari, D.; Di Mauro, A.; Di Nezza, P.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Drozhzhova, T.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Engel, H.; Epple, E.; Erazmus, B.; Erdemir, I.; Erhardt, F.; Espagnon, B.; Estienne, M.; Esumi, S.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Feuillard, V. J. G.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Gauger, E. F.; Germain, M.; Gheata, A.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Goméz Coral, D. M.; Gomez Ramirez, A.; Gonzalez, V.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Grachov, O. A.; Graczykowski, L. K.; Graham, K. L.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Gronefeld, J. M.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Harris, J. W.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Heide, M.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Hess, B. A.; Hetland, K. F.; Hillemanns, H.; Hippolyte, B.; Hosokawa, R.; Hristov, P.; Huang, M.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Inaba, M.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacobs, P. M.; Jadhav, M. B.; Jadlovska, S.; Jadlovsky, J.; Jahnke, C.; Jakubowska, M. J.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jung, H.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kamin, J.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karayan, L.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Mohisin Khan, M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, D. W.; Kim, D. J.; Kim, D.; Kim, H.; Kim, J. S.; Kim, M.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Klewin, S.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobayashi, T.; Kobdaj, C.; Kofarago, M.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kopcik, M.; Kour, M.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Koyithatta Meethaleveedu, G.; Králik, I.; Kravčáková, A.; Kretz, M.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kuhn, C.; Kuijer, P. G.; Kumar, A.; Kumar, J.; Kumar, L.; Kumar, S.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Ladron de Guevara, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, G. R.; Lee, S.; Lehas, F.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; León Vargas, H.; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Luettig, P.; Lunardon, M.; Luparello, G.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manko, V.; Manso, F.; Manzari, V.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Martin Blanco, J.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Massacrier, L.; Mastroserio, A.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; Mcdonald, D.; Meddi, F.; Melikyan, Y.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Minervini, L. M.; Mischke, A.; Mishra, A. N.; Miskowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montaño Zetina, L.; Montes, E.; Moreira De Godoy, D. A.; Moreno, L. A. P.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Mulligan, J. D.; Munhoz, M. G.; Munzer, R. H.; Murray, S.; Musa, L.; Musinsky, J.; Naik, B.; Nair, R.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Natal da Luz, H.; Nattrass, C.; Nayak, K.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Noris, J. C. C.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Oliveira Da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Orava, R.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, P.; Paić, G.; Pal, S. K.; Pan, J.; Pandey, A. K.; Papcun, P.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Patra, R. N.; Paul, B.; Peitzmann, T.; Pereira Da Costa, H.; Pereira De Oliveira Filho, E.; Peresunko, D.; Pérez Lara, C. E.; Perez Lezama, E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Ploskon, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rami, F.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Read, K. F.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Revol, J.-P.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rocco, E.; Rodríguez Cahuantzi, M.; Rodriguez Manso, A.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Romita, R.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Šándor, L.; Sandoval, A.; Sano, M.; Sarkar, D.; Scapparone, E.; Scarlassara, F.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schuchmann, S.; Schukraft, J.; Schulc, M.; Schuster, T.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Šefčík, M.; Seger, J. E.; Sekiguchi, Y.; Sekihata, D.; Selyuzhenkov, I.; Senosi, K.; Senyukov, S.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shangaraev, A.; Sharma, A.; Sharma, M.; Sharma, M.; Sharma, N.; Shigaki, K.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singha, S.; Singhal, V.; Sinha, B. C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Søgaard, C.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; Sozzi, F.; Spacek, M.; Spiriti, E.; Sputowska, I.; Spyropoulou-Stassinaki, M.; Stachel, J.; Stan, I.; Stefanek, G.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Suljic, M.; Sultanov, R.; Šumbera, M.; Szabo, A.; Szanto de Toledo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Tabassam, U.; Takahashi, J.; Tambave, G. J.; Tanaka, N.; Tangaro, M. A.; Tarhini, M.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thomas, D.; Tieulent, R.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trombetta, G.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vajzer, M.; Vala, M.; Valencia Palomo, L.; Vallero, S.; Van Der Maarel, J.; Van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Venaruzzo, M.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Verweij, M.; Vickovic, L.; Viesti, G.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Villatoro Tello, A.; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Vyushin, A.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Watanabe, D.; Watanabe, Y.; Weber, M.; Weber, S. G.; Weiser, D. F.; Wessels, J. P.; Westerhoff, U.; Whitehead, A. M.; Wiechula, J.; Wikne, J.; Wilde, M.; Wilk, G.; Wilkinson, J.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yaldo, C. G.; Yang, H.; Yang, P.; Yano, S.; Yasar, C.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yoon, J. H.; Yurchenko, V.; Yushmanov, I.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zardoshti, N.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhang, C.; Zhang, Z.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.
2016-03-01
The production of prompt charmed mesons D0, D+ and D∗+, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at the centre-of-mass energy per nucleon pair, sqrt{s_{NN}} , of 2 .76 TeV. The production yields for rapidity | y| < 0 .5 are presented as a function of transverse momentum, p T, in the interval 1-36 GeV /c for the centrality class 0-10% and in the interval 1-16 GeV /c for the centrality class 30-50%. The nuclear modification factor R AA was computed using a proton-proton reference at sqrt{s}=2.76 TeV, based on measurements at sqrt{s}=7 TeV and on theoretical calculations. A maximum suppression by a factor of 5-6 with respect to binary-scaled pp yields is observed for the most central collisions at p T of about 10 GeV /c. A suppression by a factor of about 2-3 persists at the highest p T covered by the measurements. At low p T (1-3 GeV /c), the R AA has large uncertainties that span the range 0.35 (factor of about 3 suppression) to 1 (no suppression). In all p T intervals, the R AA is larger in the 30-50% centrality class compared to central collisions. The D-meson R AA is also compared with that of charged pions and, at large p T, charged hadrons, and with model calculations. [Figure not available: see fulltext.
Markowitz, Joseph; Chen, Ijen; Gitti, Rossi; Baldisseri, Donna M; Pan, Yongping; Udan, Ryan; Carrier, France; MacKerell, Alexander D; Weber, David J
2004-10-07
The binding of S100B to p53 down-regulates wild-type p53 tumor suppressor activity in cancer cells such as malignant melanoma, so a search for small molecules that bind S100B and prevent S100B-p53 complex formation was undertaken. Chemical databases were computationally searched for potential inhibitors of S100B, and 60 compounds were selected for testing on the basis of energy scoring, commercial availability, and chemical similarity clustering. Seven of these compounds bound to S100B as determined by steady state fluorescence spectroscopy (1.0 microM < or = K(D) < or = 120 microM) and five inhibited the growth of primary malignant melanoma cells (C8146A) at comparable concentrations (1.0 microM < or = IC(50) < or = 50 microM). Additionally, saturation transfer difference (STD) NMR experiments confirmed binding and qualitatively identified protons from the small molecule at the small molecule-S100B interface. Heteronuclear single quantum coherence (HSQC) NMR titrations indicate that these compounds interact with the p53 binding site on S100B. An NMR-docked model of one such inhibitor, pentamidine, bound to Ca(2+)-loaded S100B was calculated using intermolecular NOE data between S100B and the drug, and indicates that pentamidine binds into the p53 binding site on S100B defined by helices 3 and 4 and loop 2 (termed the hinge region).
Figueira, João; Rodrigues, João; Valkonen, Arto
2013-04-01
In the title Ru(II) carboxyl-ate compound, [Ru(C2H3O2)(C26H24P2)2](CF3O3S)0.75Cl0.25, the distorted tris-bidentate octa-hedral stereochemistry about the Ru(II) atom in the complex cation comprises four P-atom donors from two 1,2-bis-(diphenyl-phosphan-yl)ethane ligands [Ru-P = 2.2881 (13)-2.3791 (13) Å] and two O-atom donors from the acetate ligand [Ru-O = 2.191 (3) and 2.202 (3) Å]. The disordered counter-anions are located on the same site in the structure in a 3:1 ratio, the expanded formula comprising four complex cations, three trifluoro-methane-sulfonate anions and one chloride anion, with two such formula units in the unit cell.
Clegg, William; Harrington, Ross W; North, Michael; Villuendas, Pedro
2010-09-17
The combined use of the bimetallic aluminum(salen) complex [Al(salen)](2)O and tetrabutylammonium bromide (or tributylamine) is found to catalyze the reaction between epoxides and carbon disulfide. In most cases, at 50 °C, the reaction produces 1,3-oxathiolane-2-thiones, while at 90 °C, 1,3-dithiolane-2-thiones are the main product. The structure and stereochemistry of three of the 1,3-dithiolane-2-thiones is unambiguously determined by X-ray crystallographic analysis, and this is used to correct errors in the literature concerning the synthesis of cyclic di- and trithiocarbonates. The kinetics of 1,3-oxathiolane-2-thione synthesis are determined, and the resulting rate equation, along with a stereochemical analysis of the reaction and catalyst modification studies, is used to determine a mechanism for the synthesis of 1,3-oxathiolane-2-thiones which contrasts with the mechanism previously determined for cyclic carbonate synthesis using the same bimetallic aluminum(salen) complex.
Zwingmann, Claudia; Leibfritz, Dieter; Hazell, Alan S
2003-06-01
A central question in manganese neurotoxicity concerns mitochondrial dysfunction leading to cerebral energy failure. To obtain insight into the underlying mechanism(s), the authors investigated cell-specific pathways of [1-13C]glucose metabolism by high-resolution multinuclear NMR-spectroscopy. Five-day treatment of neurons with 100-micro mol/L MnCl(2) led to 50% and 70% decreases of ATP/ADP and phosphocreatine-creatine ratios, respectively. An impaired flux of [1-13C]glucose through pyruvate dehydrogenase, which was associated with Krebs cycle inhibition and hence depletion of [4-13C]glutamate, [2-13C]GABA, and [13C]glutathione, hindered the ability of neurons to compensate for mitochondrial dysfunction by oxidative glucose metabolism and further aggravated neuronal energy failure. Stimulated glycolysis and oxidative glucose metabolism protected astrocytes against energy failure and oxidative stress, leading to twofold increased de novo synthesis of [3-13C]lactate and fourfold elevated [4-13C]glutamate and [13C]glutathione levels. Manganese, however, inhibited the synthesis and release of glutamine. Comparative NMR data obtained from cocultures showed disturbed astrocytic function and a failure of astrocytes to provide neurons with substrates for energy and neurotransmitter metabolism, leading to deterioration of neuronal antioxidant capacity (decreased glutathione levels) and energy metabolism. The results suggest that, concomitant to impaired neuronal glucose oxidation, changes in astrocytic metabolism may cause a loss of intercellular homeostatic equilibrium, contributing to neuronal dysfunction in manganese neurotoxicity.
Applegate, Jason C; Okeowo, Monisola K; Erickson, Nathan R; Neal, Brad M; Berrie, Cindy L; Gerasimchukand, Nikolay N; Barybin, Mikhail V
2016-02-01
Mercapto (-SH) and isocyano (-N≡C) terminated conducting π-linkers are often employed in the ever-growing quest for organoelectronic materials. While such systems typically involve symmetric dimercapto or diisocyano anchoring of the organic bridge, this article introduces the chemistry of a linear azulenic π-linker equipped with one mercapto and one isocyano terminus. The 2-isocyano-6-mercaptoazulene platform was efficiently accessed from 2-amino-6-bromo-1,3-diethoxycarbonylazulene in four steps. The 2-N≡C end of this 2,6-azulenic motif was anchrored to the [Cr(CO) 5 ] fragment prior to formation of its 6-SH terminus. Metalation of the 6-SH end of [(OC) 5 Cr(η 1 -2-isocyano-1,3-diethoxycarbonyl-6-mercaptoazulene)] ( 7 ) with Ph 3 PAuCl, under basic conditions, afforded X-ray structurally characterized heterobimetallic Cr 0 /Au I ensemble [(OC) 5 Cr(μ-η 1 :η 1 -2-isocyano-1,3-diethoxycarbonyl-6-azulenylthiolate)AuPPh 3 ] ( 8 ). Analysis of the 13 C NMR chemical shifts for the [(NC)Cr(CO) 5 ] core in a series of the related complexes [(OC) 5 Cr(2-isocyano-6-X-1,3-diethoxy-carbonylazulene)] (X = -N≡C, Br,H, SH, SCH 2 CH 2 CO 2 CH 2 CH 3 , SAuPPh 3 ) unveiled remarkably consistent inverse-linear correlations δ( 13 C O trans ) vs. δ( 13 C N) and δ( 13 C O cis ) vs. δ( 13 C N) that appear to hold well beyond the above 2-isocyanoazulenic series to include complexes [(OC) 5 Cr(CNR)] containing strongly electron-withdrawing substituents R, such as CF 3 , CFClCF 2 Cl, C 2 F 3 , and C 6 F 5 . In addition to functioning as asensitive 13 C NMR handle, the essentially C 4v -symmetric [(-NC)Cr(CO) 5 ] moiety proved to be an informative, remote, ν N≡C /ν C≡O infrared reporter in probing chemisorption of 7 on the Au(111) surface.
Nettekoven, U; Widhalm, M; Kalchhauser, H; Kamer, P C; van Leeuwen, P W; Lutz, M; Spek, A L
2001-02-09
Three series of P-chiral diphosphines based on ferrocene (1a-f, 2a-c) and biferrocenyl skeletons (3a-c), including novel ligands 1f and 3c, were employed in palladium-catalyzed allylic substitution reactions. Steric effects imposed by the phosphine residues were studied using C2-symmetrical donors 1 (1 = 1,1'-bis(arylphenylphosphino)ferrocene with aryl groups a = 1-naphthyl, b = 2-naphthyl, c = 2-anisyl, d = 2-biphenylyl, e = 9-phenanthryl, and f = ferrocenyl), whereas para-methoxy- and/or para-trifluoromethyl substitution of the phenyl moieties in 1a enabled investigation of ligand electronic effects applying ferrocenyl diphosphines 2a-c. Ligands 3 (3 = 2,2'-bis- (arylphenylphosphino)-1,1'-biferrocenyls with aryl substituents a,c = 1-naphthyl (diastereomers) and b = 2-biphenylyl) allowed for comparison of backbone structure effects (bite angle variation) in catalysis. Linear and cyclic allylic acetates served as substrates in typical test reactions; upon attack of soft carbon and nitrogen nucleophiles on (E)-1,3-diphenylprop-2-ene-1-yl acetate the respective malonate, amine, or imide products were obtained in enantioselectivities of up to 99% ee. A crystal structure analysis of a palladium 1,3-diphenyl-eta 3-allyl complex incorporating ligand (S,S)-1a revealed a marked distortion of the allyl fragment, herewith defining the regioselectivity of nucleophile addition.
11 CFR 100.24 - Federal election activity (2 U.S.C. 431(20)).
Code of Federal Regulations, 2010 CFR
2010-01-01
...)). 100.24 Section 100.24 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.24 Federal election activity (2 U.S.C. 431(20)). (a) As used in... ending on the date of the general election, up to and including the date of any general runoff. (ii) The...
Binary stars in the Galactic thick disc
NASA Astrophysics Data System (ADS)
Izzard, Robert G.; Preece, Holly; Jofre, Paula; Halabi, Ghina M.; Masseron, Thomas; Tout, Christopher A.
2018-01-01
The combination of asteroseismologically measured masses with abundances from detailed analyses of stellar atmospheres challenges our fundamental knowledge of stars and our ability to model them. Ancient red-giant stars in the Galactic thick disc are proving to be most troublesome in this regard. They are older than 5 Gyr, a lifetime corresponding to an initial stellar mass of about 1.2 M⊙. So why do the masses of a sizeable fraction of thick-disc stars exceed 1.3 M⊙, with some as massive as 2.3 M⊙? We answer this question by considering duplicity in the thick-disc stellar population using a binary population-nucleosynthesis model. We examine how mass transfer and merging affect the stellar mass distribution and surface abundances of carbon and nitrogen. We show that a few per cent of thick-disc stars can interact in binary star systems and become more massive than 1.3 M⊙. Of these stars, most are single because they are merged binaries. Some stars more massive than 1.3 M⊙ form in binaries by wind mass transfer. We compare our results to a sample of the APOKASC data set and find reasonable agreement except in the number of these thick-disc stars more massive than 1.3 M⊙. This problem is resolved by the use of a logarithmically flat orbital-period distribution and a large binary fraction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shetty, Nishant D.; Reddy, Manchi C.M.; Palaninathan, Satheesh K.
2010-10-11
PII constitutes a family of signal transduction proteins that act as nitrogen sensors in microorganisms and plants. Mycobacterium tuberculosis (Mtb) has a single homologue of PII whose precise role has as yet not been explored. We have solved the crystal structures of the Mtb PII protein in its apo and ATP bound forms to 1.4 and 2.4 {angstrom} resolutions, respectively. The protein forms a trimeric assembly in the crystal lattice and folds similarly to the other PII family proteins. The Mtb PII:ATP binary complex structure reveals three ATP molecules per trimer, each bound between the base of the T-loop ofmore » one subunit and the C-loop of the neighboring subunit. In contrast to the apo structure, at least one subunit of the binary complex structure contains a completely ordered T-loop indicating that ATP binding plays a role in orienting this loop region towards target proteins like the ammonium transporter, AmtB. Arg38 of the T-loop makes direct contact with the {gamma}-phosphate of the ATP molecule replacing the Mg{sup 2+} position seen in the Methanococcus jannaschii GlnK1 structure. The C-loop of a neighboring subunit encloses the other side of the ATP molecule, placing the GlnK specific C-terminal 3{sub 10} helix in the vicinity. Homology modeling studies with the E. coli GlnK:AmtB complex reveal that Mtb PII could form a complex similar to the complex in E. coli. The structural conservation and operon organization suggests that the Mtb PII gene encodes for a GlnK protein and might play a key role in the nitrogen regulatory pathway.« less
The 100-C-7 Remediation Project. An Overview of One of DOE's Largest Remediation Projects - 13260
DOE Office of Scientific and Technical Information (OSTI.GOV)
Post, Thomas C.; Strom, Dean; Beulow, Laura
The U.S. Department of Energy Richland Operations Office (RL), U.S. Environmental Protection Agency (EPA) and Washington Closure Hanford LLC (WCH) completed remediation of one of the largest waste sites in the U.S. Department of Energy complex. The waste site, 100-C-7, covers approximately 15 football fields and was excavated to a depth of 85 feet (groundwater). The project team removed a total of 2.3 million tons of clean and contaminated soil, concrete debris, and scrap metal. 100-C-7 lies in Hanford's 100 B/C Area, home to historic B and C Reactors. The waste site was excavated in two parts as 100-C-7 andmore » 100-C-7:1. The pair of excavations appear like pit mines. Mining engineers were hired to design their tiered sides, with safety benches every 17 feet and service ramps which allowed equipment access to the bottom of the excavations. The overall cleanup project was conducted over a span of almost 10 years. A variety of site characterization, excavation, load-out and sampling methodologies were employed at various stages of remediation. Alternative technologies were screened and evaluated during the project. A new method for cost effectively treating soils was implemented - resulting in significant cost savings. Additional opportunities for minimizing waste streams and recycling were identified and effectively implemented by the project team. During the final phase of cleanup the project team applied lessons learned throughout the entire project to address the final, remaining source of chromium contamination. The C-7 cleanup now serves as a model for remediating extensive deep zone contamination sites at Hanford. (authors)« less
Physical and biogeochemical correlates of spatio-temporal variation in the δ13C of marine macroalgae
NASA Astrophysics Data System (ADS)
Mackey, Andrew P.; Hyndes, Glenn A.; Carvalho, Matheus C.; Eyre, Bradley D.
2015-05-01
Carbon isotope ratios (13C/12C) can be used to trace sources of production supporting food chains, as δ13C undergoes relatively small and predictable increases (∼0.5‰) through each trophic level. However, for this technique to be precise, variation in δ13C signatures of different sources of production (baseline sources) must be clearly defined and distinct from each other. Despite this, δ13C in the primary producers of marine systems are highly variable over space and time, due to the complexity of physical and biogeochemical processes that drive δ13C variation at the base of these foodwebs. We measured spatial and temporal variation in the δ13C of two species of macroalgae that are important dietary components of grazers over temperate reefs: the small kelp Ecklonia radiata, and the red alga Plocamium preissianum, and related any variation to a suite of physical and biogeochemical variables. Patterns in δ13C variation, over different spatial (10 s m to 100 km) and temporal scales (weeks to seasons), differed greatly between taxa, but these were partly explained by the δ13C of dissolved inorganic carbon (DIC) and light. However, while the δ13C in E. radiata was not related to water temperature, a highly significant proportion of the spatio-temporal variation in δ13C of P. preissianum was explained by temperature alone. Accordingly, we applied this relationship to project (across temperate Australasia) and forecast (in time, south-western Australia) patterns in P. preissianum δ13C. The mean projected δ13C for P. preissianum in the study region varied by only ∼1‰ over a 12-month period, compared to ∼3‰ over 2000 km. This illustrates the potential scale in the shift of δ13C in baseline food sources over broad scales, and its implications to food web studies. While we show that those relationships differ across taxonomic groups, we recommend developing models to explain variability in δ13C of other baseline sources to facilitate the interpretation of variation in δ13C of consumers in food webs, particularly where data for baselines are absent over broad scales.
Ocular Protection from Laser Hazards. Phase 2
1993-10-31
including optics,electronics and surface protection. Physical vapor deposition ( PVD ) is the commonly used method to produce thin film coatings . Standard...control computer. In this part of the program, we intended to investigate various binary combinations of the following coating materials: SiC 2, Ta2O5 ...80 [ o Ta2O5 60 40 U 20 0 i I I Thickness [nm] 0 50 100 150 200 250 Figure 2. Dependence of the temperature in the coating chamber as a function of
Foesel, Bärbel U; Mayer, Susanne; Luckner, Manja; Wanner, Gerhard; Rohde, Manfred; Overmann, Jörg
2016-01-01
Three Gram-negative, non-spore-forming, encapsulated bacteria were isolated from a Namibian river-bank soil (strains 277T and 307) and a semiarid savannah soil (strain A2-1cT). 16S rRNA gene sequence analyses placed them within subdivision 1 of the Acidobacteria and revealed 100 % similarity between strains 277T and 307 and 98.2 % similarity between A2-1cT and the former two strains. The closest relatives with validly published names were Telmatobacter bradus, Acidicapsa borealis and Acidicapsa ligni (94.7-95.9 % similarity to the type strains). Cells of all three strains were rod-shaped and motile and divided by binary fission. Ultrastructural analyses revealed a thick cell envelope, resulting mainly from a thick periplasmic space. Colonies of strains 277T and 307 were white to cream and light pink, respectively, while strain A2-1cT displayed a bright pink colour. All three strains were aerobic, chemoheterotrophic mesophiles with a broad temperature range for growth and a moderately acidic pH optimum. Sugars and complex proteinaceous substrates were the preferred carbon and energy sources. A few polysaccharides were degraded. The major quinone in all three strains was MK-8; MK-7 occurred in strain A2-1cT as a minor compound. Major fatty acids were iso-C15 : 0 and iso-C17 : 1ω7c. In addition, iso-C17 : 0 occurred in significant amounts. The DNA G+C contents of strains 277T, 307 and A2-1cT were 59.6, 59.9 and 58.5 mol%, respectively. Based on these characteristics, the three isolates are assigned to two novel species of the novel genus Occallatibacter gen. nov., Occallatibacter riparius sp. nov. [type strain 277T ( = DSM 25168T = LMG 26948T) and reference strain 307 ( = DSM 25169 = LMG 26947)] and Occallatibacter savannae sp. nov. [type strain A2-1cT ( = DSM 25170T = LMG 26946T)]. Together with several other recently described taxa, the novel isolates provide the basis for an emended description of the established family Acidobacteriaceae.
11 CFR 100.29 - Electioneering communication (2 U.S.C. 434(f)(3)).
Code of Federal Regulations, 2010 CFR
2010-01-01
... Commission regulations; (4) Constitutes a candidate debate or forum conducted pursuant to 11 CFR 110.13, or that solely promotes such a debate or forum and is made by or on behalf of the person sponsoring the debate or forum; or (5) Is paid for by a candidate for State or local office in connection with an...
11 CFR 100.29 - Electioneering communication (2 U.S.C. 434(f)(3)).
Code of Federal Regulations, 2011 CFR
2011-01-01
... Commission regulations; (4) Constitutes a candidate debate or forum conducted pursuant to 11 CFR 110.13, or that solely promotes such a debate or forum and is made by or on behalf of the person sponsoring the debate or forum; or (5) Is paid for by a candidate for State or local office in connection with an...
Carbon Chain Anions and the Growth of Complex Organic Molecules in Titan’s Ionosphere
NASA Astrophysics Data System (ADS)
Desai, R. T.; Coates, A. J.; Wellbrock, A.; Vuitton, V.; Crary, F. J.; González-Caniulef, D.; Shebanits, O.; Jones, G. H.; Lewis, G. R.; Waite, J. H.; Cordiner, M.; Taylor, S. A.; Kataria, D. O.; Wahlund, J.-E.; Edberg, N. J. T.; Sittler, E. C.
2017-08-01
Cassini discovered a plethora of neutral and ionized molecules in Titan’s ionosphere including, surprisingly, anions and negatively charged molecules extending up to 13,800 u q-1. In this Letter, we forward model the Cassini electron spectrometer response function to this unexpected ionospheric component to achieve an increased mass resolving capability for negatively charged species observed at Titan altitudes of 950-1300 km. We report on detections consistently centered between 25.8 and 26.0 u q-1 and between 49.0-50.1 u q-1 which are identified as belonging to the carbon chain anions, CN-/C3N- and/or C2H-/C4H-, in agreement with chemical model predictions. At higher ionospheric altitudes, detections at 73-74 u q-1 could be attributed to the further carbon chain anions C5N-/C6H- but at lower altitudes and during further encounters extend over a higher mass/charge range. This, as well as further intermediary anions detected at >100 u, provide the first evidence for efficient anion chemistry in space involving structures other than linear chains. Furthermore, at altitudes below <1100 km, the low-mass anions (<150 u q-1) were found to deplete at a rate proportional to the growth of the larger molecules, a correlation that indicates the anions are tightly coupled to the growth process. This study adds Titan to an increasing list of astrophysical environments where chain anions have been observed and shows that anion chemistry plays a role in the formation of complex organics within a planetary atmosphere as well as in the interstellar medium.
Park, Ji-Young; Lee, Seon-Hwa; Kim, Kyoung-Rok; Park, Jin-Byung; Oh, Deok-Kun
2015-08-20
Linoleate 13-hydratase from Lactobacillus acidophilus LMG 11470 converted linoleic acid to hydroxyl fatty acid, which was identified as 13S-hydroxy-9(Z)-octadecenoic acid (13-HOD) by GC-MS and NMR. The expression of linoleate 13-hydratase gene in Escherichia coli was maximized by using pACYC plasmid and super optimal broth with catabolite repression (SOC) medium containing 40mM Mg(2+). To optimize induction conditions, recombinant cells were cultivated at 37°C, 1mM isopropyl-β-d-thiogalactopyranoside was added at 2h, and the culture was further incubated at 16°C for 18h. Recombinant cells expressing linoleate 13-hydratase from L. acidophilus were obtained under the optimized expression conditions and used for 13-HOD production from linoleic acid. The optimal reaction conditions were pH 6.0, 40°C, 0.25% (v/v) Tween 40, 25gl(-1) cells, and 100gl(-1) linoleic acid, and under these conditions, whole recombinant cells produced 79gl(-1) 13-HOD for 3h with a conversion yield of 79% (w/w), a volumetric productivity of 26.3gl(-1)h(-1), and a specific productivity of 1.05g g-cells(-1)h(-1). To the best of our knowledge, the recombinant cells produced hydroxy fatty acid with the highest concentration and productivity reported so far. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Bramanti, Emilia; D'Ulivo, Lucia; Lomonte, Cristina; Onor, Massimo; Zamboni, Roberto; Raspi, Giorgio; D'Ulivo, Alessandro
2006-10-02
A new procedure is proposed for the sampling and storage of hydrogen sulphide (H2S) and volatile thiols (methanethiol or methyl mercaptan, ethanethiol and propanethiol) for their determination by liquid chromatography. The sampling procedure is based on the trapping/pre-concentration of the analytes in alkaline aqueous solution containing an organic mercurial probe p-hydroxymercurybenzoate, HO-Hg-C6H4-COO- (PHMB), where they are derivatized to stable PHMB complexes based on mercury-sulfur covalent bonds. PHMB complexes are separated on a C18 reverse phase column, allowing their determination by liquid chromatography coupled with sequential non-selective UV-vis (DAD) and mercury specific (chemical vapor generation atomic fluorescence spectrometry, CVGAFS) on-line detectors. PHMB complexes, S(PHMB)2CH3S-PHMB, C2H5S-PHMB and C3H7S-PHMB, are stable alt least for 12 h at room temperature and for 3 months if stored frozen (-20 degrees C). The best analytical figures of merits in the optimized conditions were obtained by CVGAFS detection, with detection limits (LODc) of 9.7 microg L(-1) for H2S, 13.7 microg L(-1) for CH(3)SH, 17.7 microg L(-1) for C2H5SH and 21.7 microg L(-1) for C3H7SH in the trapping solution in form of RS-PHMB complexes, the relative standard deviation (R.S.D.) ranging between 1.0 and 1.5%, and a linear dynamic range (LDR) between 10 and 9700 microg L(-1). Conventional UV absorbance detectors tuned at 254 nm can be employed as well with comparable R.S.D. and LDR, but with LODc one order of magnitude higher than AFS detector and lower specificity. The sampling procedure followed by LC-DAD-CVGAFS analysis has been validated, as example, for H2S determination by a certified gas permeation tube as a source of 3.071+/-0.154 microg min(-1) of H2S, giving a recovery of 99.8+/-7% and it has been applied to the determination of sulfur compounds in real gas samples (biogas and the air of a plant for fractional distillation of crude oil).
Xu, Jianpo; Xu, Dandan; Wan, Muyang; Yin, Li; Wang, Xiaofei; Wu, Lijie; Liu, Yanhua; Liu, Xiaoyun; Zhou, Yan; Zhu, Yongqun
2017-12-19
The type IVb secretion system (T4BSS) of Legionella pneumophila is a multiple-component apparatus that delivers ∼300 virulent effector proteins into host cells. The injected effectors modulate host cellular processes to promote bacterial infection and proliferation. IcmS and IcmW are two conserved small, acidic adaptor proteins that form a binary complex to interact with many effectors and facilitate their translocation. IcmS and IcmW can also interact with DotL, an ATPase of the type IV coupling protein complex (T4CP). However, how IcmS-IcmW recognizes effectors, and what the roles of IcmS-IcmW are in T4BSSs are unclear. In this study, we found that IcmS and IcmW form a 1:1 heterodimeric complex to bind effector substrates. Both IcmS and IcmW adopt new structural folds and have no structural similarities with known effector chaperones. IcmS has a compact global structure with an α/β fold, while IcmW adopts a fully α-folded, relatively loose architecture. IcmS stabilizes IcmW by binding to its two C-terminal α-helices. Photocrosslinking assays revealed that the IcmS-IcmW complex binds its cognate effectors via an extended hydrophobic surface, which can also interact with the C terminus of DotL. A crystal structure of the DotL-IcmS-IcmW complex reveals extensive and highly stable interactions between DotL and IcmS-IcmW. Moreover, IcmS-IcmW recruits LvgA to DotL and assembles a unique T4CP. These data suggest that IcmS-IcmW also functions as an inseparable integral component of the DotL-T4CP complex in the bacterial inner membrane. This study provides molecular insights into the dual roles of the IcmS-IcmW complex in T4BSSs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Halfen, D. T.; Ziurys, L. M.; Woolf, N. J., E-mail: halfend@email.arizona.edu
A study has been conducted of {sup 12}C/{sup 13}C ratios in five complex molecules in the Galactic center. H{sub 2}CS, CH{sub 3}CCH, NH{sub 2}CHO, CH{sub 2}CHCN, and CH{sub 3}CH{sub 2}CN and their {sup 13}C-substituted species have been observed in numerous transitions at 1, 2, and 3 mm, acquired in a spectral-line survey of Sgr B2(N), conducted with the telescopes of the Arizona Radio Observatory (ARO). Between 22 and 54 individual, unblended lines for the {sup 12}C species and 2–54 for {sup 13}C-substituted analogs were modeled in a global radiative transfer analysis. All five molecules were found to consistently exhibit twomore » velocity components near V {sub LSR} ∼ 64 and 73 km s{sup −1}, with column densities ranging from N {sub tot} ∼ 3 × 10{sup 14} − 4 × 10{sup 17} cm{sup −2} and ∼2 × 10{sup 13} − 1 × 10{sup 17} cm{sup −2} for the {sup 12}C and {sup 13}C species, respectively. Based on 14 different isotopic combinations, ratios were obtained in the range {sup 12}C/{sup 13}C = 15 ± 5 to 33 ± 13, with an average value of 24 ± 7, based on comparison of column densities. These measurements better anchor the {sup 12}C/{sup 13}C ratio at the Galactic center, and suggest a slightly revised isotope gradient of {sup 12}C/{sup 13}C = 5.21(0.52) D {sub GC} + 22.6(3.3). As indicated by the column densities, no preferential {sup 13}C enrichment was found on the differing carbon sites of CH{sub 3}CCH, CH{sub 2}CHCN, and CH{sub 3}CH{sub 2}CN. Because of the elevated temperatures in Sgr B2(N), {sup 13}C isotopic substitution is effectively “scrambled,” diminishing chemical fractionation effects. The resulting ratios thus reflect stellar nucleosynthesis and Galactic chemical evolution, as is likely the case for most warm clouds.« less
NASA Astrophysics Data System (ADS)
Gning, Youssou; Sow, Malick; Traoré, Alassane; Dieng, Matabara; Diakhate, Babacar; Biaye, Mamadi; Wagué, Ahmadou
2015-01-01
In the present work a special computational program Scilab (Scientific Laboratory) in the complex rotation method has been used to calculate resonance parameters of ((2s2) 1Se, (2s2p) 1,3P0) and ((3s2) 1Se, (3s3p) 1,3P0) states of helium-like ions with Z≤10. The purpose of this study required a mathematical development of the Hamiltonian applied to Hylleraas wave function for intrashell states, leading to analytical expressions which are carried out under Scilab computational program. Results are in compliance with recent theoretical calculations.
Photometric Solutions of Three Eclipsing Binary Stars Observed from Dome A, Antarctica
NASA Astrophysics Data System (ADS)
Liu, N.; Fu, J. N.; Zong, W.; Wang, L. Z.; Uddin, S. A.; Zhang, X. B.; Zhang, Y. P.; Cang, T. Q.; Li, G.; Yang, Y.; Yang, G. C.; Mould, J.; Morrell, N.
2018-04-01
Based on spectroscopic observations for the eclipsing binaries CSTAR 036162 and CSTAR 055495 with the WiFeS/2.3 m telescope at SSO and CSTAR 057775 with the Mage/Magellan I at LCO in 2017, stellar parameters are derived. More than 100 nights of almost-continuous light curves reduced from the time-series photometric observations by CSTAR at Dome A of Antarctic in i in 2008 and in g and r in 2009, respectively, are applied to find photometric solutions for the three binaries with the Wilson–Devinney code. The results show that CSTAR 036162 is a detached configuration with the mass ratio q = 0.354 ± 0.0009, while CSTAR 055495 is a semi-detached binary system with the unusual q = 0.946 ± 0.0006, which indicates that CSTAR 055495 may be a rare binary system with mass ratio close to one and the secondary component filling its Roche Lobe. This implies that a mass-ratio reversal has just occurred and CSTAR 055495 is in a rapid mass-transfer stage. Finally, CSTAR 057775 is believed to be an A-type W UMa binary with q = 0.301 ± 0.0008 and a fill-out factor of f = 0.742(8).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kanatzidis, Mercouri; Riley, Brian; Chun, Jaehun
This report documents the work done under NEUP grant to examine the capability of novel chalcogels and some binary metal chalcogenides as a host matrix for the capture of gaseous iodine and the feasibility of their iodine-laden materials to be converted into a permanent waste form. The presented work was conducted over last two years. A number of novel chalcogels Zn 2Sn 2S 6, Sb 4Sn 4S 12, NiMoS 4, CoMoS 4, antimony sulfide (SbS x) chalcogels, silver functionalized chalcogels and binary metal sulfides (Sb 2S 3) were developed and studies for their iodine absorption efficacies. A new and simplemore » route was devised for the large scale preparation of antimony sulfide chalcogel. The chalcogel was obtained by treating Sb 2S 3 with Na 2S in the presence of water followed by addition of formamide. The obtained gels have a low-density sponge like network of meso porous nature having BET surface area of 125 m 2/g. The chalcogels, silver functionalized chalcogel and the binary metal sulfides were exposed to iodine vapors in a closed container. Silver-functionalized chalcogels and Sb 2S 3 powders showed iodine uptake up to 100 wt%, the highest iodine uptake of 200 wt% was observed for the SbS-III chalcogel. The PXRD patterns of iodine-laden specimens revealed that iodine shows spontaneous chemisorption to the matrix used. The iodine loaded chalcogels and the binary chalcogenides were sealed under vacuum in fused silica ampoules and heated in a temperature controlled furnace. The consolidated products were analyzed by PXRD, energy dispersive spectroscopy (EDS), UV-Vis and Raman spectroscopy. The final products were found to be amorphous in most of the cases with high amount (~4-35 wt%) of iodine and aapproximately ~60- 90 % of the absorbed iodine could be consolidated into the final waste form. Alginate reinforced composite scaffolds with SbS/SnS chalcogels and Sb 2S 3 bulk powder were also fabricated aiming to study their efficacy as host matrices in capturing the gaseous molecular iodine in dynamic mode from nuclear spent fuel. The obtained composites looks robust in comparison to their respective pristine chalcogels and Sb 2S 3 bulk powder.« less
NASA Astrophysics Data System (ADS)
Ding, S.; Webster, J. D.
2017-12-01
Magmatic degassing involving multiple volatile components (C, O, H, S, Cl, etc.) is one of the key factors influencing the timing and nature of volcanic eruptions, and the chemistry of volcanic gases released to the surface. In particular, exsolution of these volatiles from silicic magma during ascent could trigger explosive volcanic eruptions, which can exert strong impacts on surface temperature, ecology and human health. However, quantitative evaluation of this process in silicic magma remains ambiguous due to the lack of experiments in such chemically complex systems. Rhyolite-fluid(s) equilibria experiments were conducted in an IHPVat 100-300 MPa and 800 ° C to determine the solubilities, fluid-melt partitioning, and mixing properties of H2O, CO2, S, and Cl in the oxygen fugacity (fO2) range of FMQ to FMQ+3. The integrated bulk fluids contain up to 94 mol% H2O, 32 mol% CO2, 1 mol% S and 1mol% Cl. Rhyolite melt dissolved 20- 770 ppm CO2 and 4-7 wt.% H2O, varying with pressure, fluid composition, and fO2. Concentrations of H2O and CO2 in melt from C-O-H-S-Cl- bearing experiments at 100 and 200 MPa, and from C-O-H only experiments are generally consistent with the predictions of existing CO2-H2O solubility models based on the C-O-H only system [1-4], while the solubilities of H2O and CO2 in melt with addition of S±Cl at 300 MPa are less than those of the C-O-H- only system. This reduction in H2O and CO2 solubilities exceeds the effects of simple dilution of the coexisting fluid owing to addition of other volatiles, and rather, reflects complex mixing relations. Rhyolite melt also dissolved 20-150 ppm S and 850-2000 ppm Cl, varying with pressure. At 300 MPa, S concentrations in the melt change with fO2. The partitioning of CO2 and S between fluid and melt varies as a function of fluid composition and fO2. Solubilities and complex mixing relationships of CO2, H2O, S and Cl revealed in our experiments can be applied to massive rhyolitic eruptions like those of the Bishop tuff, Toba tuff and Pinatubo to better understand the degassing process, to estimate fluid compositions, and thus, to evaluate the potential environmental impacts of these super eruptions. [1] Ghiorso amd Gualda, 2015, CMP; [2] Liu et al., 2005, J. Volcanol. Geotherm. Res.; [3] Newman and Lowenstern, 2002, Comput. Geosci.; [3] Tamic et al., 2001, Chem. Geol..
Arumugam, Kuppuswamy; Bollinger, James E; Fink, Mark; Donahue, James P
2007-04-16
The reaction of P4S10 with acyloins, RC(O)CH(OH)R, in refluxing dioxane, followed by the addition of alkylating agents, forms dithiolene thiophosphoryl thiolate compounds, (R2C2S2)P(S)(SR'), which are readily isolated and purified. The compounds that have been prepared and identified spectroscopically are those with R = p-anisyl, R' = Me (1); R = p-anisyl, R' = Bz (2); R = Ph, R' = Me (4); R = Et, R' = Bz (5). Compounds 1, 2, and 4 were structurally characterized by X-ray crystallography and found to possess a tetrahedral coordination geometry about the phosphorus atom, with overall Cs symmetry. In each case, the mirror plane bisects the dithiolene S-P-S chelate and contains the thiophosphoryl bond, which ranges in length from 1.9241(8) to 1.9361(7) A. The use of 2-(bromomethyl)naphthalene as organic electrophile in the P4S10/acyloin reaction produced bis(2-methylnaphthalenyl) disulfide as the only identifiable product. The substitution of Lawesson's reagent for P4S10 in reactions with acyloins produced deoxy acyloin rather than products resulting from chalcogen exchange. Compounds 1-2 and 4-5 are Group 5 analogues of 1,3-dithiol-2-ones, (R2C2S2)C=O, and undergo a similar hydrolysis in aqueous base to liberate ene-1,2-dithiolate dianions from which corresponding metal dithiolene complexes may be prepared. Deprotection of 1 in MeO-/MeOH, followed by the addition of NiCl2.6H2O and then I2, produces square planar [Ni(S2C2(C6H4-p-OCH3)2)2] (8) in 93% yield. A high-resolution structure of 8 (P) reveals dithiolene C-C and C-S bond lengths that are clearly indicative of the thionyl radical monoanionic nature of the ligand. The use of isolated (R2C2S2)P(S)(SR') compounds as a dithiolene ligand source for the preparation of metal dithiolene complexes offers the advantages of clean reactivity and high yield.
NASA Astrophysics Data System (ADS)
Niedermeier, D.; Budke, C.; Koop, T.; Hartmann, S.; Augustin, S.; Stratmann, F.; Wex, H.
2013-12-01
Heterogeneous ice nucleation, a fundamental process for ice formation in the atmosphere, has been observed to occur in clouds at temperatures higher than -20 °C (Kanitz et al., 2011). However, laboratory studies showed that mineral dust particles, which are the most abundant atmospheric ice nuclei (IN), are ice active at lower temperature (Murray et al., 2012). Biological particles such as bacteria nucleate ice at higher temperatures similar to those observed in the atmosphere. But their atmospheric relevance is controversially discussed (Hartmann et al., 2013; Hoose et al., 2010). In order to achieve a better understanding, fundamental processes underlying ice nucleation on bacteria should be investigated. Within the Ice Nuclei research UnIT (INUIT), the ice nucleating ability of SNOMAX, which contains non-viable Pseudomonas syringae bacteria as well as their fragments, was quantified using different measurement devices featuring different measurement techniques. Here, results determined with the Bielefeld Ice Nucleation ARraY (BINARY, Budke et al., 2013) and the Leipzig Aerosol Cloud Interaction Simulator (LACIS, Hartmann et al., 2011) are presented exemplarily. Within these devices, droplets with different amounts of SNOMAX were exposed to supercooling temperatures until they froze (BINARY: cooling rate: 1K/min; LACIS: residence time of supercooled droplets at a certain temperature: ~0.2s). Frozen fractions were determined in a temperature range of ca. -4 to -20 °C. These fractions increase steeply and, in part, level off at values lower than 100% (i.e., they reach a plateau value indicating the number of SNOMAX IN per droplet) depending on the SNOMAX concentration. With increasing amount of SNOMAX per droplet, the frozen fraction curve is shifted to higher temperature and the plateau value increases, reaching 100% for the highest SNOMAX concentrations. It has been suggested that ice nucleation active (INA) macromolecules, i.e. protein complexes in the case of bacteria, initiate the freezing process (Wolber et al. 1986). The Soccer ball model (Niedermeier et al., 2011) was used to parameterize the ice nucleation behavior of these INA macromolecules. One parameter set (mean contact angle and its standard deviation) could be derived that matches the experimental results of both devices. This parameterization can be used to describe the ice nucleation behavior of the INA bacteria in atmospheric models for a given number concentration being present in the atmosphere. Acknowledgement This work is funded by the German Research Foundation (DFG projects WE 4722/1-1 and KO 2944/2-1, both part of the research unit INUIT). References Budke et al., Proc.19th ICNAA, Fort Collins, CO, USA, 949-951, 2013. Hartmann et al., Atmos. Chem. Phys., 11, 1753-1767, 2011. Hartmann et al., Atmos. Chem. Phys., 13, 5751-5766, 2013. Hoose et al., Environ. Res. Lett. 5, 024009, 2010. Kanitz et al., Geophys. Res. Lett., 38, L17802, 2011. Niedermeier et al., Atmos. Chem. Phys., 11, 8767-8775, 2011. Murray et al., Chem. Soc. Rev., 41, 6519-6554, 2012. Wolber et al., P. Natl. A. Sci., 83, 7256-7260, 1986.
Owusu-Kwarteng, James; Wuni, Alhassan; Akabanda, Fortune; Tano-Debrah, Kwaku; Jespersen, Lene
2017-03-14
B. cereus are of particular interest in food safety and public health because of their capacity to cause food spoilage and disease through the production of various toxins. The aim of this study was to determine the prevalence, virulence factor genes and antibiotic resistance profile of B. cereus sensu lato isolated from cattle grazing soils and dairy products in Ghana. A total of 114 samples made up of 25 soil collected from cattle grazing farm land, 30 raw milk, 28 nunu (yoghurt-like product) and 31 woagashie (West African soft cheese). Ninety-six B. cereus sensu lato isolates from 54 positive samples were screened by PCR for the presence of 8 enterotoxigenic genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK and entFM), and one emetic gene (ces). Phenotypic resistance to 15 antibiotics were also determined for 96 B. cereus sensu lato isolates. About 72% (18 of 25 soil), 47% (14 of 30 raw milk), 35% (10 of 28 nunu) and 39% (12 of 31 woagashi) were positive for B. cereus sensu lato with mean counts (log 10 cfu/g) of 4.2 ± 1.8, 3.3 ± 2.0, 1.8 ± 1.4 and 2.6 ± 1.8 respectively. The distribution of enterotoxigenic genes revealed that 13% (12/96 isolates) harboured all three gene encoding for haemolytic enterotoxin HBL complex genes (hblA, hblC and hblD), 25% (24/96 isolates) possessed no HBL gene, whereas 63% (60/96 isolates) possessed at least one of the three HBL genes. All three genes encoding for non-haemolytic enterotoxin (nheA, nheB and nheC) were detected in 60% (57/96) isolates, 14% (13/96) harboured only one gene, 19% (18/96) whereas 8% possessed none of the NHE genes. The detection rates of cytk, entFM, and ces genes were 75, 67 and 9% respectively. Bacillus cereus s. l. isolates were generally resistant to β-lactam antibiotics such as ampicillin (98%), oxacillin (92%), penicillin (100%), amoxicillin (100%), and cefepime (100%) but susceptible to other antibiotics tested. Bacillus cereus s. l. is prevalent in soil, raw milk and dairy products in Ghana. However, loads are at levels considered to be safe for consumption. Various enterotoxin genes associated with virulence of B. cereus are widespread among the isolates.
Telomere dysfunction and cell survival: Roles for distinct TIN2-containing complexes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Sahn-ho; Davalos, Albert R.; Heo, Seok-Jin
Telomeres are maintained by three DNA binding proteins (TRF1, TRF2 and POT1), and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. Along with two other proteins, TPP1 and hRap1, these form a soluble complex that may be the core telomere maintenance complex. It is not clear whether sub-complexes also exist in vivo. We provide evidence for two TIN2 sub-complexes with distinct functions in human cells. We isolated these two TIN2 sub-complexes from nuclear lysates of unperturbed cells and cells expressing TIN2 mutants TIN2-13, TIN2-15C, which cannot bind TRF2 or TRF1, respectively. In cells withmore » wild-type p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere uncapping and eventual growth arrest. In cells lacking p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere dysfunction and cell death. Our findings suggest that distinct TIN2 complexes exist, and that TIN2-15C-sensitive subcomplexes are particularly important for cell survival in the absence of functional p53.« less
NASA Astrophysics Data System (ADS)
H. E. S. S. Collaboration; Abramowski, A.; Acero, F.; Aharonian, F.; Akhperjanian, A. G.; Anton, G.; Balzer, A.; Barnacka, A.; Becherini, Y.; Becker, J.; Bernlöh, K.; Birsin, E.; Biteau, J.; Bochow, A.; Boisson, C.; Bolmont, J.; Bordas, P.; Brucker, J.; Brun, F.; Brun, P.; Bulik, T.; Büsching, I.; Carrigan, S.; Casanova, S.; Cerruti, M.; Chadwick, P. M.; Charbonnier, A.; Chaves, R. C. G.; Cheesebrough, A.; Cologna, G.; Conrad, J.; Dalton, M.; Daniel, M. K.; Davids, I. D.; Degrange, B.; Deil, C.; Dickinson, H. J.; Djannati-Ataï, A.; Domainko, W.; Drury, L. O'C.; Dubus, G.; Dutson, K.; Dyks, J.; Dyrda, M.; Egberts, K.; Eger, P.; Espigat, P.; Fallon, L.; Fegan, S.; Feinstein, F.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Füßling, M.; Gallant, Y. A.; Gast, H.; Gérard, L.; Gerbig, D.; Giebels, B.; Glicenstein, J. F.; Glück, B.; Göring, D.; Häffner, S.; Hague, J. D.; Hahn, J.; Hampf, D.; Harris, J.; Hauser, M.; Heinz, S.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hillert, A.; Hinton, J. A.; Hofmann, W.; Hofverberg, P.; Holler, M.; Horns, D.; Jacholkowska, A.; de Jager, O. C.; Jahn, C.; Jamrozy, M.; Jung, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kaufmann, S.; Keogh, D.; Khélifi, B.; Klochkov, D.; Klużniak, D.; Kneiske, T.; Komin, Nu.; Kosack, K.; Kossakowski, R.; Krayzel, F.; Laffon, H.; Lamanna, G.; Lenain, J.-P.; Lennarz, D.; Lohse, T.; Lopatin, A.; Lu, C.-C.; Marandon, V.; Marcowith, A.; Masbou, J.; Maxted, N.; Mayer, M.; McComb, T. J. L.; Medina, M. C.; Méhault, J.; Moderski, R.; Mohamed, M.; Moulin, E.; Naumann, C. L.; Naumann-Godo, M.; de Naurois, M.; Nedbal, D.; Nekrassov, D.; Nguyen, N.; Nicholas, B.; Niemiec, J.; Nolan, S. J.; Ohm, S.; de Oña Wilhelmi, E.; Opitz, B.; Ostrowski, M.; Oya, I.; Panter, M.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perez, J.; Petrucci, P.-O.; Peyaud, B.; Pita, S.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raue, M.; Rayner, S. M.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Ripken, J.; Rob, L.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Sanchez, D. A.; Santangelo, A.; Schlickeiser, R.; Schulz, A.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Sheidaei, F.; Skilton, J. L.; Sol, H.; Spengler, G.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Szostek, A.; Tavernet, J.-P.; Terrier, R.; Tluczykont, M.; Valerius, K.; van Eldik, C.; Vasileiadis, G.; Venter, C.; Viana, A.; Vincent, P.; Völk, H. J.; Volpe, F.; Vorobiov, S.; Vorster, M.; Wagner, S. J.; Ward, M.; White, R.; Wierzcholska, A.; Zacharias, M.; Zajczyk, A.; Zdziarski, A. A.; Zech, A.; Zechlin, H.-S.
2012-05-01
The Carina arm region, containing the supernova remnant SNR G284.3-1.8, the high-energy (HE; E > 100 MeV) binary 1FGL J1018.6-5856 and the energetic pulsar PSR J1016-5857 and its nebula, has been observed with the H.E.S.S. telescope array. The observational coverage of the region in very-high-energy (VHE; E > 0.1 TeV) γ-rays benefits from deep exposure (40 h) of the neighboring open cluster Westerlund 2. The observations have revealed a new extended region of VHE γ-ray emission. The new VHE source HESS J1018-589 shows a bright, point-like emission region positionally coincident with SNR G284.3-1.8 and 1FGL J1018.6-5856 and a diffuse extension towards the direction of PSR J1016-5857. A soft (Γ = 2.7 ± 0.5stat)photon index, with a differential flux at 1 TeV of N0 = (4.2 ± 1.1) × 10-13 TeV-1 cm-2 s-1 is found for the point-like source, whereas the total emission region including the diffuse emission region is well fit by a power-law function with spectral index Γ = 2.9 ± 0.4stat and differential flux at 1 TeV of N0 = (6.8 ± 1.6) × 10-13 TeV-1 cm-2 s-1. This H.E.S.S. detection motivated follow-up X-ray observations with the XMM-Newton satellite to investigate the origin of the VHE emission. The analysis of the XMM-Newton data resulted in the discovery of a bright, non-thermal point-like source (XMMU J101855.4-58564) with a photon index of Γ = 1.65 ± 0.08 in the center of SNR G284.3-1.8, and a thermal, extended emission region coincident with its bright northern filament. The characteristics of this thermal emission are used to estimate the plasma density in the region as n ≈ 0.5 cm-3 (2.9 kpc/d)2. The position of XMMU J101855.4-58564 is compatible with the position reported by the Fermi-LAT collaboration for the binary system 1FGL J1018.6-5856 and the variable Swift XRT source identified with it. The new X-ray data are used alongside archival multi-wavelength data to investigate the relationship between the VHE γ-ray emission from HESS J1018-589 and the various potential counterparts in the Carina arm region.
Mendiburu, Andrés Z; de Carvalho, João A; Coronado, Christian R
2015-03-21
Estimation of the lower flammability limits of C-H compounds at 25 °C and 1 atm; at moderate temperatures and in presence of diluent was the objective of this study. A set of 120 C-H compounds was divided into a correlation set and a prediction set of 60 compounds each. The absolute average relative error for the total set was 7.89%; for the correlation set, it was 6.09%; and for the prediction set it was 9.68%. However, it was shown that by considering different sources of experimental data the values were reduced to 6.5% for the prediction set and to 6.29% for the total set. The method showed consistency with Le Chatelier's law for binary mixtures of C-H compounds. When tested for a temperature range from 5 °C to 100 °C, the absolute average relative errors were 2.41% for methane; 4.78% for propane; 0.29% for iso-butane and 3.86% for propylene. When nitrogen was added, the absolute average relative errors were 2.48% for methane; 5.13% for propane; 0.11% for iso-butane and 0.15% for propylene. When carbon dioxide was added, the absolute relative errors were 1.80% for methane; 5.38% for propane; 0.86% for iso-butane and 1.06% for propylene. Copyright © 2014 Elsevier B.V. All rights reserved.
Leggett, C. J.; Parker, B. F.; Zhang, Z.; Dau, P. D.; Lukens, W. W.; Peterson, S. M.; Cardenas, A. J. P.; Warner, M. G.; Gibson, J. K.; Arnold, J.
2016-01-01
A non-oxido V(v) complex with glutaroimide-dioxime (H3L), a ligand for recovering uranium from seawater, was synthesized from aqueous solution as Na[V(L)2]·2H2O, and the structure determined by X-ray diffraction. It is the first non-oxido V(v) complex that has been directly synthesized in and crystallized from aqueous solution. The distorted octahedral structure contains two fully deprotonated ligands (L3–) coordinating to V5+, each in a tridentate mode via the imide N (R V–N = 1.96 Å) and oxime O atoms (R V–O = 1.87–1.90 Å). Using 17O-labelled vanadate as the starting material, concurrent 17O/51V/1H/13C NMR, in conjunction with ESI-MS, unprecedentedly demonstrated the stepwise displacement of the oxido V 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 O bonds by glutaroimide-dioxime and verified the existence of the “bare” V5+/glutaroimide-dioxime complex, [V(L)2]–, in aqueous solution. In addition, the crystal structure of an intermediate 1 : 1 V(v)/glutaroimide-dioxime complex, [VO2(HL)]–, in which the oxido bonds of vanadate are only partially displaced, corroborates the observations by NMR and ESI-MS. Results from this work provide important insights into the strong sorption of vanadium on poly(amidoxime) sorbents in the recovery of uranium from seawater. Also, because vanadium plays important roles in biological systems, the syntheses of the oxido and non-oxido V5+ complexes and the unprecedented demonstration of the displacement of the oxido VO bonds help with the on-going efforts to develop new vanadium compounds that could be of importance in biological applications. PMID:28660055
The binary protein-protein interaction landscape of Escherichia coli
Rajagopala, Seesandra V.; Vlasblom, James; Arnold, Roland; Franca-Koh, Jonathan; Pakala, Suman B.; Phanse, Sadhna; Ceol, Arnaud; Häuser, Roman; Siszler, Gabriella; Wuchty, Stefan; Emili, Andrew; Babu, Mohan; Aloy, Patrick; Pieper, Rembert; Uetz, Peter
2014-01-01
Efforts to map the Escherichia coli interactome have identified several hundred macromolecular complexes, but direct binary protein-protein interactions (PPIs) have not been surveyed on a large scale. Here we performed yeast two-hybrid screens of 3,305 baits against 3,606 preys (~70% of the E. coli proteome) in duplicate to generate a map of 2,234 interactions, approximately doubling the number of known binary PPIs in E. coli. Integration of binary PPIs and genetic interactions revealed functional dependencies among components involved in cellular processes, including envelope integrity, flagellum assembly and protein quality control. Many of the binary interactions that could be mapped within multi-protein complexes were informative regarding internal topology and indicated that interactions within complexes are significantly more conserved than those interactions connecting different complexes. This resource will be useful for inferring bacterial gene function and provides a draft reference of the basic physical wiring network of this evolutionarily significant model microbe. PMID:24561554
Kerkhoff, Claus; Nacken, Wolfgang; Benedyk, Malgorzata; Dagher, Marie Claire; Sopalla, Claudia; Doussiere, Jacques
2005-03-01
The Ca2+- and arachidonic acid-binding S100A8/A9 protein complex was recently identified by in vitro studies as a novel partner of the phagocyte NADPH oxidase. The present study demonstrated its functional relevance by the impaired oxidase activity in neutrophil-like NB4 cells, after specific blockage of S100A9 expression, and bone marrow polymorphonuclear neutrophils from S100A9-/- mice. The impaired oxidase activation could also be mimicked in a cell-free system by pretreatment of neutrophil cytosol with an S100A9-specific antibody. Further analyses gave insights into the molecular mechanisms by which S100A8/A9 promoted NADPH oxidase activation. In vitro analysis of oxidase activation as well as protein-protein interaction studies revealed that S100A8 is the privileged interaction partner for the NADPH oxidase complex since it bound to p67phox and Rac, whereas S100A9 did interact with neither p67phox nor p47phox. Moreover, S100A8/A9 transferred the cofactor arachidonic acid to NADPH oxidase as shown by the impotence of a mutant S100A8/A9 complex unable to bind arachidonic acid to enhance NADPH oxidase activity. It is concluded that S100A8/A9 plays an important role in phagocyte NADPH oxidase activation.
NASA Astrophysics Data System (ADS)
Androniuk, Iuliia; Landesman, Catherine; Henocq, Pierre; Kalinichev, Andrey G.
2017-06-01
As a first step in developing better molecular scale understanding of the effects of organic additives on the adsorption and mobility of radionuclides in cement under conditions of geological nuclear waste repositories, two complementary approaches, wet chemistry experiments and molecular dynamics (MD) computer simulations, were applied to study the sorption behaviour of two simple model systems: gluconate and uranyl on calcium silicate hydrate phases (C-S-H) - the principal mineral component of hardened cement paste (HCP). Experimental data on sorption and desorption kinetics and isotherms of adsorption for gluconate/C-S-H and U(VI)/C-S-H binary systems were collected and quantitatively analysed for C-S-H samples synthesised with various Ca/Si ratios (0.83, 1.0, 1.4) corresponding to various stages of HCP aging and degradation. Gluconate labelled with 14C isotope was used in order to improve the sensitivity of analytical detection technique (LSC) at particularly low concentrations (10-8-10-5 mol/L). There is a noticeable effect of Ca/Si ratio on the gluconate sorption on C-S-H, with stronger sorption at higher Ca/Si ratios. Sorption of organic anions on C-S-H is mediated by the presence of Ca2+ at the interface and strongly depends on the surface charge and Ca2+ concentration. In parallel, classical MD simulations of the same model systems were performed in order to identify specific surface sorption sites most actively involved in the sorption of gluconate and uranyl on C-S-H and to clarify molecular mechanisms of adsorption.
NASA Astrophysics Data System (ADS)
Chauhan, H. P. S.; Carpenter, Jaswant; Joshi, Sapana
2014-09-01
The bis(N,N-dimethyldithiocarbamato-S,S‧)antimony(III) complexes have been obtained by the reaction of chloro bis(N,N-dimethyldithiocarbamato-S,S‧)antimony(III) with corresponding oxo or thio donor ligands such as sodium benzoate 1, sodium thioglycolate 2, phenol 3, sodium 1-propanethiolate 4, potassium thioacetate 5, sodium salicylate 6, ethane-1,2-dithiolate 7 and disodium oxalate 8. These complexes have been characterized by the physicochemical [melting point, molecular weight determination and elemental analysis (C, H, N, S and Sb)], spectral [UV-Visible, FT-IR, far IR, NMR (1H and 13C)], thermogravimetric (TG & DTA) analysis, ESI-Mass and powder X-ray diffraction studies. Thermogravimetric analysis of the complexes confirmed the final decomposition product as highly pure antimony sulfide (Sb2S3) and powder X-ray diffraction studies show that the complexes are in lower symmetry with monoclinic crystal lattice and nano-ranged particle size (11.51-20.82 nm). The complexes have also been screened against some bacterial and fungal strains for their antibacterial and antifungal activities and compared with standard drugs. These show that the complexes have greater activities against some human pathogenic bacteria and fungi than the activities of standard drugs.
11 CFR 100.26 - Public communication (2 U.S.C. 431(22)).
Code of Federal Regulations, 2010 CFR
2010-01-01
... 11 Federal Elections 1 2010-01-01 2010-01-01 false Public communication (2 U.S.C. 431(22)). 100.26...) General Definitions § 100.26 Public communication (2 U.S.C. 431(22)). Public communication means a communication by means of any broadcast, cable, or satellite communication, newspaper, magazine, outdoor...
11 CFR 100.26 - Public communication (2 U.S.C. 431(22)).
Code of Federal Regulations, 2011 CFR
2011-01-01
... 11 Federal Elections 1 2011-01-01 2011-01-01 false Public communication (2 U.S.C. 431(22)). 100.26...) General Definitions § 100.26 Public communication (2 U.S.C. 431(22)). Public communication means a communication by means of any broadcast, cable, or satellite communication, newspaper, magazine, outdoor...
11 CFR 100.26 - Public communication (2 U.S.C. 431(22)).
Code of Federal Regulations, 2012 CFR
2012-01-01
... 11 Federal Elections 1 2012-01-01 2012-01-01 false Public communication (2 U.S.C. 431(22)). 100.26...) General Definitions § 100.26 Public communication (2 U.S.C. 431(22)). Public communication means a communication by means of any broadcast, cable, or satellite communication, newspaper, magazine, outdoor...
11 CFR 100.26 - Public communication (2 U.S.C. 431(22)).
Code of Federal Regulations, 2014 CFR
2014-01-01
... 11 Federal Elections 1 2014-01-01 2014-01-01 false Public communication (2 U.S.C. 431(22)). 100.26...) General Definitions § 100.26 Public communication (2 U.S.C. 431(22)). Public communication means a communication by means of any broadcast, cable, or satellite communication, newspaper, magazine, outdoor...
11 CFR 100.26 - Public communication (2 U.S.C. 431(22)).
Code of Federal Regulations, 2013 CFR
2013-01-01
... 11 Federal Elections 1 2013-01-01 2012-01-01 true Public communication (2 U.S.C. 431(22)). 100.26...) General Definitions § 100.26 Public communication (2 U.S.C. 431(22)). Public communication means a communication by means of any broadcast, cable, or satellite communication, newspaper, magazine, outdoor...
NASA Astrophysics Data System (ADS)
Cordiner, M. A.; Charnley, S. B.; Kisiel, Z.; McGuire, B. A.; Kuan, Y.-J.
2017-12-01
The 100 m Robert C. Byrd Green Bank Telescope K-band (KFPA) receiver was used to perform a high-sensitivity search for rotational emission lines from complex organic molecules in the cold interstellar medium toward TMC-1 (cyanopolyyne peak), focussing on the identification of new carbon-chain-bearing species as well as molecules of possible prebiotic relevance. We report a detection of the carbon-chain oxide species HC7O and derive a column density of (7.8+/- 0.9)× {10}11 cm-2. This species is theorized to form as a result of associative electron detachment reactions between oxygen atoms and C7H-, and/or reaction of C6H2 + with CO (followed by dissociative electron recombination). Upper limits are given for the related HC6O, C6O, and C7O molecules. In addition, we obtained the first detections of emission from individual 13C isotopologues of HC7N, and derive abundance ratios HC7N/HCCC13CCCCN = 110 ± 16 and HC7N/HCCCC13CCCN = 96 ± 11, indicative of significant 13C depletion in this species relative to the local interstellar elemental 12C/13C ratio of 60-70. The observed spectral region covered two transitions of HC11N, but emission from this species was not detected, and the corresponding column density upper limit is 7.4× {10}10 {{cm}}-2 (at 95% confidence). This is significantly lower than the value of 2.8× {10}11 {{cm}}-2 previously claimed by Bell et al. and confirms the recent nondetection of HC11N in TMC-1 by Loomis et al. Upper limits were also obtained for the column densities of malononitrile and the nitrogen heterocycles quinoline, isoquinoline, and pyrimidine.
High-velocity runaway stars from three-body encounters
NASA Astrophysics Data System (ADS)
Gvaramadze, V. V.; Gualandris, A.; Portegies Zwart, S.
2010-01-01
We performed numerical simulations of dynamical encounters between hard, massive binaries and a very massive star (VMS; formed through runaway mergers of ordinary stars in the dense core of a young massive star cluster) to explore the hypothesis that this dynamical process could be responsible for the origin of high-velocity (≥ 200 - 400 km s-1) early or late B-type stars. We estimated the typical velocities produced in encounters between very tight massive binaries and VMSs (of mass of ≥ 200 M⊙) and found that about 3 - 4% of all encounters produce velocities ≥ 400 km s-1, while in about 2% of encounters the escapers attain velocities exceeding the Milky Ways's escape velocity. We therefore argue that the origin of high-velocity (≥ 200 - 400 km s-1) runaway stars and at least some so-called hypervelocity stars could be associated with dynamical encounters between the tightest massive binaries and VMSs formed in the cores of star clusters. We also simulated dynamical encounters between tight massive binaries and single ordinary 50 - 100 M⊙ stars. We found that from 1 to ≃ 4% of these encounters can produce runaway stars with velocities of ≥ 300 - 400 km s-1 (typical of the bound population of high-velocity halo B-type stars) and occasionally (in less than 1% of encounters) produce hypervelocity (≥ 700 km s-1) late B-type escapers.
Hyde, Eva I; Callow, Philip; Rajasekar, Karthik V; Timmins, Peter; Patel, Trushar R; Siligardi, Giuliano; Hussain, Rohanah; White, Scott A; Thomas, Christopher M; Scott, David J
2017-08-30
The ParB protein, KorB, from the RK2 plasmid is required for DNA partitioning and transcriptional repression. It acts co-operatively with other proteins, including the repressor KorA. Like many multifunctional proteins, KorB contains regions of intrinsically disordered structure, existing in a large ensemble of interconverting conformations. Using NMR spectroscopy, circular dichroism and small-angle neutron scattering, we studied KorB selectively within its binary complexes with KorA and DNA, and within the ternary KorA/KorB/DNA complex. The bound KorB protein remains disordered with a mobile C-terminal domain and no changes in the secondary structure, but increases in the radius of gyration on complex formation. Comparison of wild-type KorB with an N-terminal deletion mutant allows a model of the ensemble average distances between the domains when bound to DNA. We propose that the positive co-operativity between KorB, KorA and DNA results from conformational restriction of KorB on binding each partner, while maintaining disorder. © 2017 The Author(s).
NASA Astrophysics Data System (ADS)
Barot, D. K.; Chaube, H. A.; Rana, V. A.
2017-05-01
The complex relative dielectric function ɛ*(ω) = ɛ'-jɛ″ of binary mixture of 1-Butyl-3-methylimadazolium (BMiCl) with water of varying concentration have been measured using Precision LCR meter in the frequency range 20 Hz to 2 MHz at 293.15 K. The dielectric and electrical properties of BMiCl and water are represented in terms of electrical conductivity σ*(ω) and complex relative dielectric function ɛ*(ω). To describe the relationship of the electrical conductivity with concentration, the empirical Casteel-Amis (C-A) equation was used. The influence of concentration variation of BMiCl in water to the various electrical parameters was discussed. All of these presentations are used to explore various processes contributed in the electrical/dielectric properties of the mixtures of BMiCl and water.
2011-03-01
Karystinos and D. A. Pados, “New bounds on the total squared correlation and optimum design of DS - CDMA binary signature sets,” IEEE Trans. Commun...vol. 51, pp. 48-51, Jan. 2003. [99] C. Ding, M. Golin, and T. Klφve, “Meeting the Welch and Karystinos-Pados bounds on DS - CDMA binary signature sets...Designs, Codes and Cryptography, vol. 30, pp. 73-84, Aug. 2003. [100] V. P. Ipatov, “On the Karystinos-Pados bounds and optimal binary DS - CDMA
11 CFR 100.11 - State (2 U.S.C. 431(12)).
Code of Federal Regulations, 2010 CFR
2010-01-01
... 11 Federal Elections 1 2010-01-01 2010-01-01 false State (2 U.S.C. 431(12)). 100.11 Section 100.11 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.11 State (2 U.S.C. 431(12)). State means each State of the United States, the District of...
Identification of Au–S complexes on Au(100)
Walen, Holly; Liu, Da -Jiang; Oh, Junepyo; ...
2016-01-25
In this study, using a combination of scanning tunneling microscopy and density functional theory (DFT) calculations, we have identified a set of related Au–S complexes that form on Au(100), when sulfur adsorbs and lifts the hexagonal surface reconstruction. The predominant complex is diamond-shaped with stoichiometry Au 4S 5. All of the complexes can be regarded as combinations of S–Au–S subunits. The complexes exist within, or at the edges of, p(2 × 2) sulfur islands that cover the unreconstructed Au regions, and are observed throughout the range of S coverage examined in this study, 0.009 to 0.12 monolayers. A qualitative modelmore » is developed which incorporates competitive formation of complexes, Au rafts, and p(2 × 2) sulfur islands, as Au atoms are released by the surface structure transformation.« less
Feasibility study for a secondary Na/S battery
NASA Technical Reports Server (NTRS)
Abraham, K. M.; Schiff, R.; Brummer, S. B.
1979-01-01
The feasibility of a moderate temperature Na battery was studied. This battery is to operate at a temperature in the range of 100-150 C. Two kinds of cathode were investigated: (1) a soluble S cathode consisting of a solution of Na2Sn in an organic solvent and (2) an insoluble S cathode consisting of a transition metal dichalcogenide in contact with a Na(+)ion conducting electrolyte. Four amide solvents, dimethyl acetamide, diethyl acetamide, N-methyl acetamide and acetamide, were investigated as possible solvents for the soluble S cathode. Results of stability and electrochemical studies using these solvents are presented. The dialkyl substituted amides were found to be superior. Although the alcohol 1,3-cyclohexanediol was found to be stable in the presence of Na2Sn at 130 C, its Na2Sn solutions did not appear to have suitable electrochemical properties.
MARVELS Radial Velocity Solutions to Seven Kepler Eclipsing Binaries
NASA Astrophysics Data System (ADS)
Heslar, Michael Francis; Thomas, Neil B.; Ge, Jian; Ma, Bo; Herczeg, Alec; Reyes, Alan; SDSS-III MARVELS Team
2016-01-01
Eclipsing binaries serve momentous purposes to improve the basis of understanding aspects of stellar astrophysics, such as the accurate calculation of the physical parameters of stars and the enigmatic mass-radius relationship of M and K dwarfs. We report the investigation results of 7 eclipsing binary candidates, initially identified by the Kepler mission, overlapped with the radial velocity observations from the SDSS-III Multi-Object APO Radial-Velocity Exoplanet Large-Area Survey (MARVELS). The RV extractions and spectroscopic solutions of these eclipsing binaries were generated by the University of Florida's 1D data pipeline with a median RV precision of ~60-100 m/s, which was utilized for the DR12 data release. We performed the cross-reference fitting of the MARVELS RV data and the Kepler photometric fluxes obtained from the Kepler Eclipsing Binary Catalog (V2) and modelled the 7 eclipsing binaries in the BinaryMaker3 and PHOEBE programs. This analysis accurately determined the absolute physical and orbital parameters of each binary. Most of the companion stars were determined to have masses of K and M dwarf stars (0.3-0.8 M⊙), and allowed for an investigation into the mass-radius relationship of M and K dwarfs. Among the cases are KIC 9163796, a 122.2 day period "heartbeat star", a recently-discovered class of eccentric binaries known for tidal distortions and pulsations, with a high eccentricity (e~0.75) and KIC 11244501, a 0.29 day period, contact binary with a double-lined spectrum and mass ratio (q~0.45). We also report on the possible reclassification of 2 Kepler eclipsing binary candidates as background eclipsing binaries based on the analysis of the flux measurements, flux ratios of the spectroscopic and photometric solutions, the differences in the FOVs, the image processing of Kepler, and RV and spectral analysis of MARVELS.
NASA Astrophysics Data System (ADS)
Xu, Xiang; Guan, Huade; Skrzypek, Grzegorz; Simmons, Craig T.
2017-10-01
The stable carbon isotope composition (δ13C) has been demonstrated to be a useful indicator of environmental conditions occurring during plant growth. Previous studies suggest that tree leaf δ13C is correlated with mean annual precipitation (MAP) over a broad range of climates with precipitation between 100 and 2000 mm/year. However, this relationship confirmed at the large scale may not be present at the local scale with complex terrain where factors other than precipitation may lead to additional variability in plant water stress. In this study, we investigated δ13C of tree leaves in a native vegetation catchment over a local gradient of hydro-climatic conditions induced by two hillslopes with opposite aspects. Significant seasonal variations, calculated as a difference between the maximum and minimum δ13C values for each tree, were observed for two species, up to 1.9‰ for Eucalyptus (E.) paniculata, and up to 2.7‰ for Acacia (A.) pycnantha on the north-facing slope (NFS). Also the mean δ13C values calculated from all investigated trees of each hillslope were significantly different and leaf δ13C on the NFS was higher by 1.4 ± 0.5‰ than that on the south-facing slope (SFS). These results cannot be explained by the negligible difference in precipitation between the two hillslopes located just 200 m apart. The correlation coefficients between the δ13C of E. tree leaves and the integrated aridity index (AI) were statistically significant for temporal observations on the NFS (R2 0.18-0.44, p-value 0.00-0.06), and spatial observations (R2 = 0.35, p-value 0.05) at the end of the dry season. These results suggest that AI as a measure of plant water stress is better associated with leaf δ13C than precipitation. Therefore, leaf δ13C value can be used as a valuable proxy for plant water stress across the landscape in both time and space.
Tate, Jennifer J.; Georis, Isabelle; Rai, Rajendra; Vierendeels, Fabienne; Dubois, Evelyne; Cooper, Terrance G.
2015-01-01
The TorC1 protein kinase complex is a central component in a eukaryotic cell’s response to varying nitrogen availability, with kinase activity being stimulated in nitrogen excess by increased intracellular leucine. This leucine-dependent TorC1 activation requires functional Gtr1/2 and Ego1/3 complexes. Rapamycin inhibition of TorC1 elicits nuclear localization of Gln3, a GATA-family transcription activator responsible for the expression of genes encoding proteins required to transport and degrade poor nitrogen sources, e.g., proline. In nitrogen-replete conditions, Gln3 is cytoplasmic and Gln3-mediated transcription minimal, whereas in nitrogen limiting or starvation conditions, or after rapamycin treatment, Gln3 is nuclear and transcription greatly increased. Increasing evidence supports the idea that TorC1 activation may not be as central to nitrogen-responsive intracellular Gln3 localization as envisioned previously. To test this idea directly, we determined whether Gtr1/2- and Ego1/3-dependent TorC1 activation also was required for cytoplasmic Gln3 sequestration and repressed GATA factor-mediated transcription by abolishing the Gtr-Ego complex proteins. We show that Gln3 is sequestered in the cytoplasm of gtr1Δ, gtr2Δ, ego1Δ, and ego3Δ strains either long term in logarithmically glutamine-grown cells or short term after refeeding glutamine to nitrogen-limited or -starved cells; GATA factor−dependent transcription also was minimal. However, in all but a gtr1Δ, nuclear Gln3 localization in response to nitrogen limitation or starvation was adversely affected. Our data demonstrate: (i) Gtr-Ego-dependent TorC1 activation is not required for cytoplasmic Gln3 sequestration in nitrogen-rich conditions; (ii) a novel Gtr-Ego-TorC1 activation-independent mechanism sequesters Gln3 in the cytoplasm; (iii) Gtr and Ego complex proteins participate in nuclear Gln3-Myc13 localization, heretofore unrecognized functions for these proteins; and (iv) the importance of searching for new mechanisms associated with TorC1 activation and/or the regulation of Gln3 localization/function in response to changes in the cells’ nitrogen environment. PMID:26024867
Inspection of U.S. Flag Vessels in Foreign Countries. An Application of Cost Effectiveness Analysis.
1983-12-01
2 83 p3 18 2 7.0346.30 1 IJ 1 100 3! .20 -40 2 2 83 183 1012 23 1857.99 1 1 9 10e 1185.70 40o80 1226.50 2 02 83 183 1082 23 2477.05 1 155 ICf CCOC.CO...Q000.00 C3CC.00 0 02 83 183 108 3 a 13 1 15 ioe 0000.00 0300.00 030C.03 0 02 83 183 1082 23 24.71 1 I15 10e 0000;00 0000.00 0000.00 a 02 I~a J3fj...1541:11 1 1 63 000..83 00?J:8r CgCi:gS 2 02 83 283 C2e3 05 472.76 1 C61 035 0000.0 OOOC.OC 030c0.00 0 03 83 183 1082 23 4583 .5 112 088 5,2.00 35.50
Hu, Jia; Feng, Hao; Xie, Yaoming; King, R Bruce; Schaefer, Henry F
2018-03-29
Stepwise interaction of first row transition metal atoms with 1,5-cyclooctadiene to give (C 8 H 12 ) 2 M complexes is studied using the M06-L/DZP density functional method. The experimentally known (C 8 H 12 ) 2 Ni is the thermodynamically most favorable complex, with a predicted geometry consistent with its experimental structure as determined by X-ray crystallography. The other transition metal atoms from scandium to zinc also interact exothermically with 1,5-cyclooctadiene to give (C 8 H 12 ) 2 M derivatives, but these exhibit lower symmetry than the S 4 symmetry exhibited by (C 8 H 12 ) 2 Ni. Carbon-hydrogen activation of CH 2 groups in a C 8 H 12 ligand is predicted for most systems. Thus, conversion of (η 2,2 -C 8 H 12 ) 2 M to (η 3,2 -C 8 H 11 )(η 2,1 -C 8 H 13 )M, through a hydride intermediate (η 3,2 -C 8 H 11 )(η 2,2 -C 8 H 12 )MH, is predicted for scandium, vanadium, chromium, manganese, and cobalt. For titanium with a low-lying empty orbital, further C-H activation through a hydride intermediate (η 6 -C 8 H 10 )(η 2,1 -C 8 H 13 )TiH is predicted, leading ultimately to (η 6 -C 8 H 10 )(η 1,1 -C 8 H 14 )Ti, in which the hexahapto η 6 -C 8 H 10 ligand is shown by NICS to be aromatic. These two C-H activation processes on a titanium center represent the dehydrogenation of 1,5-cyclooctadiene to 1,3,5-cyclooctatriene with the second 1,5-cyclooctadiene ligand as the hydrogen acceptor. For zinc C-H activation terminates at (η 1 -C 8 H 11 )(C 8 H 12 )ZnH, which has a C-Zn-H three-center bond. No energetically favorable C-H activation processes are predicted for the iron, nickel, and copper (η 2,2 -C 8 H 12 ) 2 M derivatives.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vuong, Van Hiep; Do Thi, Kim Anh; Thuan Nguyen, Khac
2016-10-14
The La-excess alloys La{sub 1+δ}(Fe{sub 0.85}Si{sub 0.15}){sub 13} (δ = 0.06 and 0.09) exhibit large magnetocaloric effect which has been attributed to the occurrence of itinerant-electron metamagnetic transition near the Curie temperature T{sub C}. The maximum entropy change −ΔS{sub m} was shown to be from 4.5 to 11.5 J/kg K for the applied field variation ΔH from 20 to 70 kOe, respectively. The estimated relative cooling power for ΔH = 70 kOe was 418 J/kg. The alloys show a typical NaZn{sub 13}-type cubic structure, featuring a doping-induced magnetovolume effect with the increase in T{sub C}. Under the applied pressure up to 2 GPa, the T{sub C} asmore » deduced from resistance measurements decreased linearly, ΔT{sub C} = 113 (for δ = 0.06) and 111 K (for δ = 0.09), together with a corresponding decrease of resistivity, Δρ = 6.1 μΩ m at room temperature for both samples. At a low pressure, the effect of spontaneous magnetostriction on T{sub C} caused by applying the pressure appeared to have a similar magnitude to that of the negative magnetovolume effect caused by La-excess doping. In comparison with other stoichiometric La(Fe{sub 1−x}Si{sub x}){sub 13} compounds, the pressure in our case was shown to have a smaller influence on T{sub C}.« less
NASA Astrophysics Data System (ADS)
Duchene, Gaspard; Lacour, Sylvestre; Moraux, Estelle; Bouvier, Jerome; Goodwin, Simon
2018-01-01
While stellar multiplicity is an ubiquitous outcome of star formation, there is a clear dichotomy between the multiplicity properties of young (~1 Myr-old) stellar clusters, like the ONC, which host a mostly field-like population of visual binaries, and those of equally young sparse populations, like the Taurus-Auriga region, which host twice as many stellar companions. Two distinct scenarios can account for this observation: one in which different star-forming regions form different number of stars, and one in which multiplicity properties are universal at birth but where internal cluster dynamics destroy many wide binaries. To solve this ambiguity, one must probe binaries that are sufficiently close so as not to be destroyed through interactions with other cluster members. To this end, we have conducted a survey for 10-100 au binaries in the ONC using the aperture masking technique with the VLT adaptive optics system. Among our sample of the 42 ONC members, we discovered 13 companions in this range of projected separations. This is consistent with the companion frequency observed in the Taurus population and twice as high as that observed among field stars. This survey thus strongly supports the idea that stellar multiplicity is characterized by near-universal initial properties that can later be dynamically altered. On the other hand, this exacerbates the question of the origin of field stars, since only clusters much denser than the ONC can effectively destroyed binaries closer than 100 au.
Synthesis Of Labeled Metabolites
Martinez, Rodolfo A.; Silks, III, Louis A.; Unkefer, Clifford J.; Atcher, Robert
2004-03-23
The present invention is directed to labeled compounds, for example, isotopically enriched mustard gas metabolites including: [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1,1'-sulfonylbis[2-(methylthio); [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1-[[2-(methylsulfinyl)ethyl]sulfonyl]-2-(methylthio); [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1,1'-sulfonylbis[2-(methylsulfinyl)]; and, 2,2'-sulfinylbis([1,2-.sup.13 C.sub.2 ]ethanol of the general formula ##STR1## where Q.sup.1 is selected from the group consisting of sulfide (--S--), sulfone (--S(O)--), sulfoxide (--S(O.sub.2)--) and oxide (--O--), at least one C* is .sup.13 C, X is selected from the group consisting of hydrogen and deuterium, and Z is selected from the group consisting of hydroxide (--OH), and --Q.sup.2 --R where Q.sup.2 is selected from the group consisting of sulfide (--S--), sulfone(--S(O)--), sulfoxide (--S(O.sub.2)--) and oxide (--O--), and R is selected from the group consisting of hydrogen, a C.sub.1 to C.sub.4 lower alkyl, and amino acid moieties, with the proviso that when Z is a hydroxide and Q.sup.1 is a sulfide, then at least one X is deuterium.
NASA Astrophysics Data System (ADS)
Dharmaraja, Jeyaprakash; Esakkidurai, Thirugnanasamy; Subbaraj, Paramasivam; Shobana, Sutha
2013-10-01
Mixed ligand Cu(II) complexes of 2-aminobenzamide (2AB) and amino acids viz., glycine (gly), L-alanine (ala), L-valine (val) and L-phenylalanine (phe) have been synthesised and characterized by various physico-chemical and spectral techniques. The calculated g-tensor values for Cu(II) complexes at 77 K and 300 K, show the distorted octahedral geometry which has been confirmed from the absorption studies. Consequently, the thermal studies illustrate that the loss of water and acetate molecules in the initial stage which are followed by the decomposition of organic residues. The powder X-ray diffraction and SEM analysis reflect that all the complexes have well-defined crystallinity nature with homogeneous morphology. The binding activities of CT DNA with CuAB complexes have been examined by absorption studies. Further, the oxidative cleavage interactions of 2-aminobenzamide and CuAB complexes with DNA were studied by gel electrophoresis method in H2O2 medium. Also, the complex formation of Cu(II) involving 2-aminobenzamide and amino acids were carried out by a combined pH-metric and spectrophotometric techniques in 50% (v/v) water-ethanol mixture at 300, 310, 320 and 330 ± 0.1 K with I = 0.15 mol dm-3 (NaClO4). In solution, CuAB and CuAB2 species has been detected and the binding modes of 2-aminobenzamide and amino acids in both binary and mixed ligand complexes are same. The calculated stabilization value of Δ log K, log X and log X' indicates higher stabilities for the mixed ligand complexes rather than their binary species. The thermodynamic parameters like ΔG, ΔH and ΔS have been determined from temperature dependence of the stability constant. In vitro biological activities of 2-aminobenzamide, CuA and CuAB complexes show remarkable activities against some bacterial and fungal strains. The percentage distribution of various binary and mixed ligand species in solution at dissimilar pH intervals were also evaluated.
NASA Astrophysics Data System (ADS)
Teleb, Said M.; Gaballa, Akmal S.; Elmosallamy, M. A. F.; Nour, El-Metwally
2005-09-01
The interaction of the mixed oxygen-nitrogen cyclic base, N, N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane (DD18C6) with π-acceptors such as picric acid (HPA) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) has been studied spectrophotometrically in chloroform at 25 °C. The results obtained indicate the formation of 1:4 charge-transfer complexes with the general formula (DD18C6)(acceptor) 4. The electronic and infrared spectra of charge-transfer complexes along with the 1H NMR spectra were recorded and discussed. Based on the data obtained, the complexes were formulated as [(DD18C6H 2)(HPA) 2](PA) 2 and [(DD18C6H 2)(DDQ) 2](DDQH) 2. A general mechanism explaining the formation of the DDQ complex has been suggested.
Boensch, C; Huang, S S; Connolly, D T; Huang, J S
1999-04-09
The cell surface retention sequence (CRS) binding protein-1 (CRSBP-1) is a newly identified membrane glycoprotein which is hypothesized to be responsible for cell surface retention of the oncogene v-sis and c-sis gene products and other secretory proteins containing CRSs. In simian sarcoma virus-transformed NIH 3T3 cells (SSV-NIH 3T3 cells), a fraction of CRSBP-1 was demonstrated at the cell surface and underwent internalization/recycling as revealed by cell surface 125I labeling and its resistance/sensitivity to trypsin digestion. However, the majority of CRSBP-1 was localized in intracellular compartments as evidenced by the resistance of most of the 35S-metabolically labeled CRSBP-1 to trypsin digestion, and by indirect immunofluorescent staining. CRSBP-1 appeared to form complexes with proteolytically processed forms (generated at and/or after the trans-Golgi network) of the v-sis gene product and with a approximately 140-kDa proteolytically cleaved form of the platelet-derived growth factor (PDGF) beta-type receptor, as demonstrated by metabolic labeling and co-immunoprecipitation. CRSBP-1, like the v-sis gene product and PDGF beta-type receptor, underwent rapid turnover which was blocked in the presence of 100 microM suramin. In normal and other transformed NIH 3T3 cells, CRSBP-1 was relatively stable and did not undergo rapid turnover and internalization/recycling at the cell surface. These results suggest that in SSV-NIH 3T3 cells, CRSBP-1 interacts with and forms ternary and binary complexes with the newly synthesized v-sis gene product and PDGF beta-type receptor at the trans-Golgi network and that the stable binary (CRSBP-1.v-sis gene product) complex is transported to the cell surface where it presents the v-sis gene product to unoccupied PDGF beta-type receptors during internalization/recycling.
Castro-Chavez, Fernando
2012-01-01
Background Three binary representations of the genetic code according to the ancient I Ching of Fu-Xi will be presented, depending on their defragging capabilities by pairing based on three biochemical properties of the nucleic acids: H-bonds, Purine/Pyrimidine rings, and the Keto-enol/Amino-imino tautomerism, yielding the last pair a 32/32 single-strand self-annealed genetic code and I Ching tables. Methods Our working tool is the ancient binary I Ching's resulting genetic code chromosomes defragged by vertical and by horizontal pairing, reverse engineered into non-binaries of 2D rotating 4×4×4 circles and 8×8 squares and into one 3D 100% symmetrical 16×4 tetrahedron coupled to a functional tetrahedron with apical signaling and central hydrophobicity (codon formula: 4[1(1)+1(3)+1(4)+4(2)]; 5:5, 6:6 in man) forming a stella octangula, and compared to Nirenberg's 16×4 codon table (1965) pairing the first two nucleotides of the 64 codons in axis y. Results One horizontal and one vertical defragging had the start Met at the center. Two, both horizontal and vertical pairings produced two pairs of 2×8×4 genetic code chromosomes naturally arranged (M and I), rearranged by semi-introversion of central purines or pyrimidines (M' and I') and by clustering hydrophobic amino acids; their quasi-identity was disrupted by amino acids with odd codons (Met and Tyr pairing to Ile and TGA Stop); in all instances, the 64-grid 90° rotational ability was restored. Conclusions We defragged three I Ching representations of the genetic code while emphasizing Nirenberg's historical finding. The synthetic genetic code chromosomes obtained reflect the protective strategy of enzymes with a similar function, having both humans and mammals a biased G-C dominance of three H-bonds in the third nucleotide of their most used codons per amino acid, as seen in one chromosome of the i, M and M' genetic codes, while a two H-bond A-T dominance was found in their complementary chromosome, as seen in invertebrates and plants. The reverse engineering of chromosome I' into 2D rotating circles and squares was undertaken, yielding a 100% symmetrical 3D geometry which was coupled to a previously obtained genetic code tetrahedron in order to differentiate the start methionine from the methionine that is acting as a codifying non-start codon. PMID:23431415
Kuhn, Félix P; Hammoud, Sonia; Lefèvre-Colau, Marie-Martine; Poiraudeau, Serge; Feydy, Antoine
2017-02-01
To determine the prevalence of simple and complex sacral perineural Tarlov cysts (TCs) in a cohort of children and adults. Retrospective observational epidemiological study assessing 1100 consecutive sacral magnetic resonance (MR) studies, including 100 children and adolescents. All patients underwent 1.5T MR imaging with T1 and T2 weighted image acquisitions in sagittal and axial planes. All perineural cysts affecting the sacral nerve roots S1-S4 were quantitatively and qualitatively assessed. Two hundred and sixty-three sacral TCs were found in 132 adult patients (13.2%), with a female predominance (68%). None was found in children. The prevalence of TCs increased with age. The average number of cysts per patient was 2.0±1.2 with a maximum of 6 cysts in a single patient. Most of the cysts (87.5%) showed a homogenous central fluid collection and a parietal course of the nerve fibers. Complex patterns were present in 33 cysts (12.5%) within which 28 cysts showed endocystic crossing of nerve fibers and 5 cysts contained internal septations. Seventy cysts (26.6%) eroded the adjacent bone and 13 cysts (4.9%) extended to the pelvis. The prevalence of sacral TCs in our cohort corresponded to 13%, with a female predominance. Interestingly no TCs were found in children or adolescents (<18 years). In relation to the non-negligible percentage of complex cysts with internal septations, or endocystic crossing of nerve fibers, pre-interventional characterization of sacral TCs might help to choose an appropriate procedure in the treatment of rare symptomatic variants. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Matsumoto, Yasumasa; Yamada, Ken-ichi; Tomioka, Kiyoshi
2008-06-20
The asymmetric construction of quaternary carbon centers by conjugate addition of Grignard reagents to 3-methyl- and 3-ethylcyclohexenones was realized in a maximum enantioselectivity of 80% by using a C 2 symmetric chiral N-heterocyclic carbene (NHC)-copper catalyst, generated from (4 S,5 S)-1,3-bis(2-methoxyphenyl)-4,5-diphenyl-4,5-dihydro-1 H-imidazol-3-ium tetrafluoroborate and copper(II) triflate. The stereostructures of the NHC-Au complexes were analyzed by X-ray crystallography, which rationalized the good stereocontrolling ability of N-aryl NHCs.
Nestor, Gustav; Anderson, Taigh; Oscarson, Stefan; Gronenborn, Angela M
2017-05-03
NMR of a uniformly 13 C-labeled carbohydrate was used to elucidate the atomic details of a sugar-protein complex. The structure of the 13 C-labeled Manα(1-2)Manα(1-2)ManαOMe trisaccharide ligand, when bound to cyanovirin-N (CV-N), was characterized and revealed that in the complex the glycosidic linkage torsion angles between the two reducing-end mannoses are different from the free trisaccharide. Distances within the carbohydrate were employed for conformational analysis, and NOE-based distance mapping between sugar and protein revealed that Manα(1-2)Manα(1-2)ManαOMe is bound more intimately with its two reducing-end mannoses into the domain A binding site of CV-N than with the nonreducing end unit. Taking advantage of the 13 C spectral dispersion of 13 C-labeled carbohydrates in isotope-filtered experiments is a versatile means for a simultaneous mapping of the binding interactions on both, the carbohydrate and the protein.
Experimental study of the Ca-Mg-Zn system using diffusion couples and key alloys
NASA Astrophysics Data System (ADS)
Zhang, Yi-Nan; Kevorkov, Dmytro; Bridier, Florent; Medraj, Mamoun
2011-03-01
Nine diffusion couples and 32 key samples were prepared to map the phase diagram of the Ca-Mg-Zn system. Phase relations and solubility limits were determined for binary and ternary compounds using scanning electron microscopy, electron probe microanalysis and x-ray diffraction (XRD). The crystal structure of the ternary compounds was studied by XRD and electron backscatter diffraction. Four ternary intermetallic (IM) compounds were identified in this system: Ca3MgxZn15-x (4.6<=x<=12 at 335 °C, IM1), Ca14.5Mg15.8Zn69.7 (IM2), Ca2Mg5Zn13 (IM3) and Ca1.5Mg55.3Zn43.2 (IM4). Three binary compounds were found to have extended solid solubility into ternary systems: CaZn11, CaZn13 and Mg2Ca form substitutional solid solutions where Mg substitutes for Zn atoms in the first two compounds, and Zn substitutes for both Ca and Mg atoms in Mg2Ca. The isothermal section of the Ca-Mg-Zn phase diagram at 335 °C was constructed on the basis of the obtained experimental results. The morphologies of the diffusion couples in the Ca-Mg-Zn phase diagram at 335 °C were studied. Depending on the terminal compositions of the diffusion couples, the two-phase regions in the diffusion zone have either a tooth-like morphology or contain a matrix phase with isolated and/or dendritic precipitates.
VizieR Online Data Catalog: HI4PI spectra and column density maps (HI4PI team+, 2016)
NASA Astrophysics Data System (ADS)
Hi4PI Collaboration; Ben Bekhti, N.; Floeer, L.; Keller, R.; Kerp, J.; Lenz, D.; Winkel, B.; Bailin, J.; Calabretta, M. R.; Dedes, L.; Ford, H. A.; Gibson, B. K.; Haud, U.; Janowiecki, S.; Kalberla, P. M. W.; Lockman, F. J.; McClure-Griffiths, N. M.; Murphy, T.; Nakanishi, H.; Pisano, D. J.; Staveley-Smith, L.
2016-09-01
The HI4PI data release comprises 21-cm neutral atomic hydrogen data of the Milky Way (-600km/s
New Insights into the Carbon Isotope Variations in Coral Skeletons (Invited)
NASA Astrophysics Data System (ADS)
Swart, P. K.
2010-12-01
The origin of the carbon isotopic composition of coral skeletons has been a subject of speculation and controversy since the first stable C and O isotopic measurements were made on corals in the 1960s and the first models of fractionation were proposed by Weber and coworkers. Early models focused on the interactions between the zooxanthellae and the coral organism and the relationship with insolation. Models were proposed that linked higher levels of photosynthesis to both 13C enriched and 13C depleted skeletal material. While the model which showed elevated 13C values related to enhanced photosynthesis generally has found favor and fits the majority of the data from experimental and field studies, more recent work has also shown the importance of the natural variability of the δ13C of the dissolved inorganic carbon on interannual and longer time scales. This variability can overwhelm photosynthetic induced variability. For example, changes over the time period of 100s of years, caused by the addition of fossil fuel CO2 to the atmosphere, has resulted in a general decline in the δ13C of coral skeletons since ~1800. These changes are even larger in instances in which local variations in δ13C are related to land use changes and the openness of the environment. Recently there has been concern regarding the decrease in the pH of the oceans related to increases in oceanic pCO2. This also has potential to changes the δ13C of the coral skeleton. Finally there are seasonal variations in the types of organic compounds being oxidized by the coral. This may be related to the types of materials being translocated between the zooxanthellae and the coral. All these factors make changes in the δ13C of coral skeletons much more than a reflection of the influence of insolation.
11 CFR 100.27 - Mass mailing (2 U.S.C. 431(23)).
Code of Federal Regulations, 2011 CFR
2011-01-01
... 11 Federal Elections 1 2011-01-01 2011-01-01 false Mass mailing (2 U.S.C. 431(23)). 100.27 Section...) General Definitions § 100.27 Mass mailing (2 U.S.C. 431(23)). Mass mailing means a mailing by United... nature within any 30-day period. A mass mailing does not include electronic mail or Internet...
11 CFR 100.27 - Mass mailing (2 U.S.C. 431(23)).
Code of Federal Regulations, 2010 CFR
2010-01-01
... 11 Federal Elections 1 2010-01-01 2010-01-01 false Mass mailing (2 U.S.C. 431(23)). 100.27 Section...) General Definitions § 100.27 Mass mailing (2 U.S.C. 431(23)). Mass mailing means a mailing by United... nature within any 30-day period. A mass mailing does not include electronic mail or Internet...
11 CFR 111.13 - Service of subpoenas, orders and notifications (2 U.S.C. 437d(a) (3), (4)).
Code of Federal Regulations, 2010 CFR
2010-01-01
... 11 Federal Elections 1 2010-01-01 2010-01-01 false Service of subpoenas, orders and notifications (2 U.S.C. 437d(a) (3), (4)). 111.13 Section 111.13 Federal Elections FEDERAL ELECTION COMMISSION GENERAL COMPLIANCE PROCEDURE (2 U.S.C. 437g, 437d(a)) Enforcement § 111.13 Service of subpoenas, orders...
Bächle, Christina; Fröhlich-Reiterer, Elke; Hahn, Eva; Icks, Andrea; Ludwig, Karl-Heinz; Mönkemöller, Kirsten; Razum, Oliver; Rosenbauer, Joachim; Holl, Reinhard W.
2015-01-01
Objective To study the impact of maternal country of birth on type-1-diabetes (T1D) therapy and outcome. Study Design and Methods 27,643 T1D patients aged ≤20 years with documented maternal country of birth from the multicenter German/Austrian diabetes patient registry (DPV) were analyzed. Patients were categorized based on their mother’s origin: Germany/Austria (reference), Turkey, Southern Europe, and Eastern Europe. To compare BMI standard deviation score (BMI-SDS), diabetes therapy and outcome between groups, multivariable regression was applied with adjustments for age, sex and duration of diabetes. Based on observed marginal frequencies, adjusted estimates were calculated. Linear regression was used for continuous data, logistic regression for binary data and Poisson regression for count data. All statistical analyses were performed using SAS 9.4. Significance was set at a two-tailed p<0.05. Results 83.3% of patients were offspring of native mothers. A Turkish, Southern or Eastern European background was documented in 2.4%, 1.7% and 4.3% of individuals. After demographic adjustment, patients with migration background had a higher mean BMI-SDS (Turkey, Southern Europe or Eastern Europe vs. Germany/Austria: 0.58±0.03, 0.40±0.04, or 0.37±0.02 vs. 0.31±0.01; ±SE) and a lower use of insulin pumps (26.8%, 27.9%, or 32.6% vs. 37.9%) compared to offspring of native mothers. Mean HbA1c was worst in individuals of Turkish mothers (Turkey vs. Germany/Austria: 69.7±0.7 vs. 66.6±0.1 mmol/mol; ±SE). Patients of Eastern European descent had an increased rate of severe hypoglycemia (22.09±0.13 vs. 16.13±0.02 events per 100 patient-years) and ketoacidosis was more prevalent in offspring of Turkish or Southern European mothers (7.50±0.10, or 7.13±0.11 vs. 6.54±0.02 events per 100 patient-years). Patients of Turkish descent were more often hospitalized (57.2±2.7 vs. 48.5±0.4 per 100 patient-years). All differences were significant. Conclusion The differences in diabetes therapy and outcome among patients with distinct migration background suggest that specific challenges have to be considered in clinical care. PMID:26295472
NASA Astrophysics Data System (ADS)
Rajegowda, H. R.; Kumar, P. Raghavendra; Hosamani, Amar; Butcher, R. J.; Naveen, S.; Lokanath, N. K.
2018-03-01
A new chiral Schiff base ligand 2-{N-[(2S)-(1-hydroxy-3-phenylpropan-2-yl]ethanimidoyl} phenol ((S)sbnd H2L) was obtained by acid catalyzed condensation of (2S)-(-)-2-amino-3-phenyl-1-propanol with 2‧-hydroxyacetophenone. The palladium complex was prepared by treating a solution of (S)sbnd H2L in acetone with a solution of Na2PdCl4 in water in 1:1 M ratio. The new ligand and its complex were characterized by FT-IR, 1H, 13C{1H} NMR spectroscopy, polarimetry and elemental analysis and their molecular structures were determined by single crystal X-ray diffraction. Both the compounds crystallizes in monoclinic system in the space group P21. There exists an intra [Osbnd H ⋯N (1.62(5) Å)] and intermolecular [Osbnd H ⋯O (1.53(5) Å) and Csbnd H ⋯O (2.59 Å)] hydrogen bonding and secondary interactions in the crystal of (S)sbnd H2L. The structure of the palladium complex was found very interesting wherein the ligand coordinated to metal center as tridentate dianionic (O-, N, O-) fashion, (S)-L, resulting in a tetranuclear palladium cluster, [Pd4((S)-L)4]. In these supramolecular structures phenolate oxygen coordinated to Pd(II) ion as Pdsbnd O terminal bonds [1.934(12) - 1.977(11) Å] and the alkoxide oxygen coordinated as Pdsbnd Osbnd Pd bridging bonds [1.993(11) - 2.012(12) Å]. The Pdsbnd N bond lengths found were in the range of 1.949(13) to 1.919(12) Å. There exists two asymmetric tetranuclear complex molecules in its crystal lattice. There exists very strong metal-metal bond interaction, Pd(2)sbnd Pd(3) [3.0410(18) Å] and Pd(6)sbnd Pd(7) [3.0517(19) Å] respectively in the two asymmetric units.
Chen, Chun-Yen; Kao, Pei-Chun; Tsai, Chia-Jung; Lee, Duu-Jong; Chang, Jo-Shu
2013-10-01
Spirulina platensis produces nutraceutical product C-phycocyanin (C-PC) and simultaneously mitigates CO2 emissions during its growth. Using a designed flat-type photobioreactor, the S. platensis biomass production was markedly enhanced, leading to a CO2 removal rate and a biomass concentration of 0.23 g/L/d and 2.25 g/L, respectively. The cell growth, CO2 fixation rate and C-PC production of S. platensis were investigated when it was cultivated under different irradiation conditions. As the light intensity increased from 100 to 700 μmol/m(2)/s, the overall biomass productivity, CO2 consumption rate and maximal C-PC productivity increased significantly to 0.74, 1.53 and 0.11 g/L/d, respectively. After determining the suitable light intensity, the nitrogen concentration was also adjusted to further enhance the performance of CO2 fixation and C-PC production. The results show that with an optimal nitrogen concentration of 0.045 M, the CO2 consumption rate and maximal C-PC productivity were further increased to 1.58 and 0.13 g/L/d, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.
Aktories, Klaus; Barth, Holger
2004-04-01
Clostridium botulinum C2 toxin is a member of the family of binary actin-ADP-ribosylating toxins. It consists of the enzyme component C2I, and the separated binding/translocation component C2II. Proteolytically activated C2II forms heptamers and binds to a carbohydrate cell surface receptor. After attachment of C2I, the toxin complex is endocytosed to reach early endosomes. At low pH of endosomes, C2II-heptamers insert into the membrane, form pores and deliver C2I into the cytosol. Here, C2I ADP-ribosylates actin at Arg177 to block actin polymerization and to induce depolymerization of actin filaments. The mini-review describes main properties of C2 toxin and discusses new findings on the involvement of chaperones in the up-take process of the toxin.
Barth, Holger; Stiles, Bradley G
2008-01-01
Binary bacterial toxins are unique AB-type toxins, composed of two non-linked proteins that act as a binding/translocation component and an enzyme component. All known actin-ADP-ribosylating toxins from clostridia possess this binary structure. This toxin family is comprised of the prototypical Clostridium botulinum C2 toxin, Clostridium perfringens iota toxin, Clostridium difficile CDT, and Clostridium spiroforme toxin. Once in the cytosol of host cells, these toxins transfer an ADP-ribose moiety from nicotinamide-adenosine-dinucleotide onto G-actin that then leads to depolymerization of actin filaments. In recent years much progress has been made towards understanding the cellular uptake mechanism of binary actin-ADP-ribosylating toxins, and in particular that of C2 toxin. Both components act in a precisely concerted manner to intoxicate eukaryotic cells. The binding/translocation (B-) component forms a complex with the enzyme (A-) component and mediates toxin binding to a cell-surface receptor. Following receptor-mediated endocytosis, the enzyme component escapes from acidic endosomes into the cytosol. Acidification of endosomes triggers pore formation by the binding/translocation component in endosomal membranes and the enzyme component subsequently translocates through the pore. This step requires a host cell chaperone, Hsp90. Due to their unique structure, binary toxins are naturally "tailor made" for transporting foreign proteins into the cytosol of host cells. Several highly specific and cell-permeable recombinant fusion proteins have been designed and successfully used in experimental cell research. This review will focus on the recent progress in studying binary actin ADP-ribosylating toxins as highly effective virulence factors and innovative tools for cell physiology as well as pharmacology.
11 CFR 100.27 - Mass mailing (2 U.S.C. 431(23)).
Code of Federal Regulations, 2014 CFR
2014-01-01
... 100.27 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.27 Mass mailing (2 U.S.C. 431(23)). Mass mailing means a mailing by United States mail or facsimile of more than 500 pieces of mail matter of an identical or substantially similar...
11 CFR 100.27 - Mass mailing (2 U.S.C. 431(23)).
Code of Federal Regulations, 2012 CFR
2012-01-01
... 100.27 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.27 Mass mailing (2 U.S.C. 431(23)). Mass mailing means a mailing by United States mail or facsimile of more than 500 pieces of mail matter of an identical or substantially similar...
11 CFR 100.27 - Mass mailing (2 U.S.C. 431(23)).
Code of Federal Regulations, 2013 CFR
2013-01-01
... 100.27 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.27 Mass mailing (2 U.S.C. 431(23)). Mass mailing means a mailing by United States mail or facsimile of more than 500 pieces of mail matter of an identical or substantially similar...
NASA Astrophysics Data System (ADS)
Sathiyaraj, Ethiraj; Padmavathy, Krishnaraj; Kumar, Chandran Udhaya; Krishnan, Kannan Gokula; Ramalingan, Chennan
2017-11-01
Bis(N-cyclopropyl-N-4-chlorobenzyldithiocarbamato-S,S‧)cadmium(II) (1) and (2,2‧-bipyridine) bis(N-cyclopropyl-N-4-chlorobenzyldithiocarbamato-S,S‧)cadmium(II) (2) have been synthesized and characterized by FT-IR, 1HNMR and 13C NMR analyses. For the complex 2, single crystal X-ray diffraction analysis and computational studies (optimized geometry, HOMO-LUMO and MEP) have been executed employing DFT/B3LYP method with LANL 2DZ basic set. The optimized bond lengths and bond angles agree well with the experimental results. The complexes 1 and 2 have been used as single source precursors for the synthesis of ethyleneglycol capped CdS1 and CdS2 nanoparticles, respectively. CdS1 and CdS2 nanoparticles have been synthesized by solvothermal method. PXRD, SEM, Elemental colour mapping, EDAX, TEM and UV-Vis spectroscopy have been used to characterize the as-prepared CdS nanoparticles. The X-ray diffraction pattern confirms both their hexagonal structures.
NASA Astrophysics Data System (ADS)
Choi, Seung Ho; Park, Sun Kyu; Lee, Jung-Kul; Kang, Yun Chan
2015-06-01
Multi-shell structured binary transition metal oxide powders with a Ni/Co mole ratio of 1:2 are prepared by a simple spray drying process. Precursor powder particles prepared by spray drying from a spray solution of citric acid and ethylene glycol have completely spherical shape, fine size, and a narrow size distribution. The precursor powders turn into multi-shell powders after a post heat-treatment at temperatures between 250 and 800 °C. The multi-shell structured powders are formed by repeated combustion and contraction processes. The multi-shell powders have mixed crystal structures of Ni1-xCo2O4-x and NiO phases regardless of the post-treatment temperature. The reversible capacities of the powders post-treated at 250, 400, 600, and 800 °C after 100 cycles are 584, 913, 808, and 481 mA h g-1, respectively. The low charge transfer resistance and high lithium ion diffusion rate of the multi-shell powders post-treated at 400 °C with optimum grain size result in superior electrochemical properties even at high current densities.
Weak interactions and cooperativity effects on disiloxane: a look at the building block of silicones
NASA Astrophysics Data System (ADS)
Martín-Fernández, Carlos; Montero-Campillo, M. Merced; Alkorta, Ibon; Elguero, José
2018-06-01
The behaviour of disiloxane 1 towards a set of Lewis acids (LA) and Lewis bases (LB) forming complexes through its oxygen and silicon atoms, respectively, was studied at the MP2/aug‧-cc-pVTZ level of theory, exploring a wide variety of non-covalent interactions. Disiloxane is a moderate electron acceptor and a good electron donor, exhibiting in the latter case binding energies up to almost -100 kJ/mol with BeCl2. Cooperativity effects were also analysed by looking at ternary 1:LA:LB complexes. Shorter intermolecular distances than in the corresponding binary complexes and a negative contribution of the three-body term to the binding energy indicate that the non-covalent interactions allowed by disiloxane through its acid and basic centres cooperate between them to reinforce both donor-acceptor pairs. These effects are particularly strong in complexes involving beryllium and triel bonds, but are also relevant for complexes containing hydrogen bonds.
Activities in Cu2S-FeS-SnS melts at 1200 °C
NASA Astrophysics Data System (ADS)
Eric, R. Hurman
1993-04-01
The dew-point technique was used to measure the vapor pressures of SnS over liquid sulfides of the system Cu2S-FeS-SnS at 1200 °C. Activities of SnS were generated from the measured vapor pressures of SnS. Activities of Cu2S and FeS were evaluated both in binary and ternary melts by Gibbs-Duhem calculations from the known SnS activity data. The systems Cu2S-SnS and Cu2S-FeS exhibit negative departures from ideal behavior, while FeS-SnS melts exhibit positive deviations.
NASA Astrophysics Data System (ADS)
Bhattacharjee, Chira R.; Goswami, Pankaj; Pramanik, Harun A. R.; Paul, Pradip C.; Mondal, Paritosh
2011-05-01
Two new mixed-ligand iron(III) complexes, [Fe(L n)(acac)(C 2H 5OH)] incorporating coordinated ethanol from the reaction solvent were accessed from the reaction of [Fe(acac) 3] with [ONO] donor dibasic tridentate unsymmetrical Schiff base ligands derived from condensation of 2-hydroxy-1-napthaldehyde with 2-aminophenol (H 2L 1) or 2-aminobenzoic acid (H 2L 2). The thermal study (TGA-DTA) provided evidence for weakly bound ethanol which is readily substituted by neutral N-donor molecule imidazole, benzimidazole or pyridine to produce an array of newer complexes, [Fe(L n)(acac)X] ( n = 1, 2; X = Im, Bim, Py). The compounds were characterized by elemental analyses, FT-IR, UV-vis, solution electrical conductivity, FAB mass, 1H and 13C NMR spectroscopy. Room temperature magnetic susceptibility measurements ( μeff ˜ 5.8 B.M.) are consistent with spin-free octahedral iron(III) complexes. Cyclic voltammetry of ethanol complexes revealed a quasi-reversible one electron redox response (Δ Ep > 100 mV) for the Fe(III)/Fe(II) couple. Low half wave redox potential ( E1/2) values suggested easy redox susceptibility. The ground state geometries of the ethanol and imidazole complexes have been ascertained to be distorted octahedral by density functional theory using DMol3 program at BLYP/DNP level.
McTernan, Patrick M; Chandrayan, Sanjeev K; Wu, Chang-Hao; Vaccaro, Brian J; Lancaster, W Andrew; Yang, Qingyuan; Fu, Dax; Hura, Greg L; Tainer, John A; Adams, Michael W W
2014-07-11
The archaeon Pyrococcus furiosus grows optimally at 100 °C by converting carbohydrates to acetate, CO2, and H2, obtaining energy from a respiratory membrane-bound hydrogenase (MBH). This conserves energy by coupling H2 production to oxidation of reduced ferredoxin with generation of a sodium ion gradient. MBH is encoded by a 14-gene operon with both hydrogenase and Na(+)/H(+) antiporter modules. Herein a His-tagged MBH was expressed in P. furiosus and the detergent-solubilized complex purified under anaerobic conditions by affinity chromatography. Purified MBH contains all 14 subunits by electrophoretic analysis (13 subunits were also identified by mass spectrometry) and had a measured iron:nickel ratio of 15:1, resembling the predicted value of 13:1. The as-purified enzyme exhibited a rhombic EPR signal characteristic of the ready nickel-boron state. The purified and membrane-bound forms of MBH both preferentially evolved H2 with the physiological donor (reduced ferredoxin) as well as with standard dyes. The O2 sensitivities of the two forms were similar (half-lives of ∼ 15 h in air), but the purified enzyme was more thermolabile (half-lives at 90 °C of 1 and 25 h, respectively). Structural analysis of purified MBH by small angle x-ray scattering indicated a Z-shaped structure with a mass of 310 kDa, resembling the predicted value (298 kDa). The angle x-ray scattering analyses reinforce and extend the conserved sequence relationships of group 4 enzymes and complex I (NADH quinone oxidoreductase). This is the first report on the properties of a solubilized form of an intact respiratory MBH complex that is proposed to evolve H2 and pump Na(+) ions. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.
Stull, Jamie A; Stich, Troy A; Service, Rachel J; Debus, Richard J; Mandal, Sanjay K; Armstrong, William H; Britt, R David
2010-01-20
Antiferromagnetically coupled Mn(III)Mn(IV) dimers have been commonly used to study biological systems that exhibit complex exchange interactions. Such is the case for the oxygen evolving complex (OEC) in photosystem II (PSII), where we have studied whether the C-terminal carboxylate of D1-Ala344 is directly bound to the Mn cluster. To probe these protein-derived carboxylate hyperfine interactions, which give direct bonding information, Q-band (34 GHz) Mims ENDOR was performed on a Mn(III)Mn(IV) dimer ([Mn(III)Mn(IV)(mu-O)(2)mu-OAc(TACN)(2)](BPh(4))(2)) (1) that was labeled with (13)C (I = (1)/(2)) at the carboxylate position of the acetate bridge. A(dip) is computed based on atomic coordinates from available X-ray crystal structures to be [-2.4, -0.8, 3.2] MHz. The value for A(iso) was determined based on simulation of the experimental ENDOR data, for complex 1 A(iso) = -1 MHz. Similar studies were then performed on PSII from Synechocystis sp. PCC 6803, in which all alanine-derived C=O groups are labeled with (13)C including the C-terminal alpha-COO(-) group of D1 (Ala344), as well as PSII proteins uniformly labeled with (13)C. Using recent X-ray crystallography data from T. elongatus the values for A(dip) were calculated and simulations of the experimental data led to A(iso) values of 1.2, 1, and 2 MHz, respectively. We infer from complex 1 that an A(iso) significantly larger than 1.2 MHz for a Mn-coordinating carboxylate moiety is unlikely. Therefore, we support the closer arrangement of Ala344 suggested by the Loll and Guskov structures and conclude that the C-terminal carboxylate of D1 polypeptide is directly bound to the Mn cluster.
Wang, Peng; Zhou, Weijian; Niu, Zhenchuan; Cheng, Peng; Wu, Shugang; Xiong, Xiaohu; Lu, Xuefeng; Du, Hua
2018-04-01
Given that cities contributed most of China's CO 2 emissions, understanding the emission characteristics of urban atmospheric CO 2 is critical for regulating CO 2 emissions. Regular observations of atmospheric CO 2 concentration, △ 14 C and δ 13 C values were performed at four different sites in Xi'an, China in 2016 to illustrate the temporal and spatial variations of CO 2 emissions and recognize their sources and sinks in urban carbon cycles. We found seasonal variations in CO 2 concentration and δ 13 C values, the peak to peak amplitude of which was 80.8ppm for CO 2 concentration and 4.0‰ for its δ 13 C. With regard to the spatial variations, the urban CO 2 "dome" effect was the most pronounced during the winter season. The use of △ 14 C combines with δ 13 C measurements aid in understanding the emission patterns. The results show that in the winter season, emissions from fossil fuel derived CO 2 (CO 2ff ) contributed 61.8±10.6% and 57.4±9.7% of the excess CO 2 (CO 2ex ) in urban and suburban areas respectively. Combining with the result of estimated δ 13 C value of fossil fuel (δ 13 C ff =-24‰), which suggest coal burning was the dominant source of fossil fuel emissions. In contrast, the proportions of CO 2ff in CO 2ex varied more in the summer season than that in the winter season, ranging from 42.3% to >100% with the average contributions of 82.5±23.8% and 90.0±24.8%. Given the estimation of δ 13 C value of local sources (δ 13 C s ) was -21.9‰ indicates that the intensively biogenic activities, such as soil respiration and corn growth have significantly impacted urban carbon cycles, and occasionally played a role of carbon sink. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Liu, Michael C.; Dupuy, Trent J.; Leggett, S. K.
2010-10-01
Highly unequal-mass ratio binaries are rare among field brown dwarfs, with the mass ratio distribution of the known census described by q (4.9±0.7). However, such systems enable a unique test of the joint accuracy of evolutionary and atmospheric models, under the constraint of coevality for the individual components (the "isochrone test"). We carry out this test using two of the most extreme field substellar binaries currently known, the T1 + T6 epsilon Ind Bab binary and a newly discovered 0farcs14 T2.0 + T7.5 binary, 2MASS J12095613-1004008AB, identified with Keck laser guide star adaptive optics. The latter is the most extreme tight binary resolved to date (q ≈ 0.5). Based on the locations of the binary components on the Hertzsprung-Russell (H-R) diagram, current models successfully indicate that these two systems are coeval, with internal age differences of log(age) = -0.8 ± 1.3(-1.0+1.2 -1.3) dex and 0.5+0.4 -0.3(0.3+0.3 -0.4) dex for 2MASS J1209-1004AB and epsilon Ind Bab, respectively, as inferred from the Lyon (Tucson) models. However, the total mass of epsilon Ind Bab derived from the H-R diagram (≈ 80 M Jup using the Lyon models) is strongly discrepant with the reported dynamical mass. This problem, which is independent of the assumed age of the epsilon Ind Bab system, can be explained by a ≈ 50-100 K systematic error in the model atmosphere fitting, indicating slightly warmer temperatures for both components; bringing the mass determinations from the H-R diagram and the visual orbit into consistency leads to an inferred age of ≈ 6 Gyr for epsilon Ind Bab, older than previously assumed. Overall, the two T dwarf binaries studied here, along with recent results from T dwarfs in age and mass benchmark systems, yield evidence for small (≈100 K) errors in the evolutionary models and/or model atmospheres, but not significantly larger. Future parallax, resolved spectroscopy, and dynamical mass measurements for 2MASS J1209-1004AB will enable a more stringent application of the isochrone test. Finally, the binary nature of this object reduces its utility as the primary T3 near-IR spectral typing standard; we suggest SDSS J1206+2813 as a replacement. Most of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.
Yang, Xiaohong; Lee, Sang-Rok; Choi, Yun-Seok; Alexander, Veronica J; Digenio, Andres; Yang, Qingqing; Miller, Yury I; Witztum, Joseph L; Tsimikas, Sotirios
2016-04-01
Elevated apoC-III levels predict increased cardiovascular risk when present on LDL and HDL particles. We developed novel high-throughput chemiluminescent ELISAs that capture apoB, lipoprotein (a) [Lp(a)], and apoA-I in plasma and then detect apoC-III on these individual lipoproteins as apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoAI complexes, respectively. We assessed the effects on these complexes of placebo or 100-300 mg volanesorsen, a generation 2.0+ antisense drug that targets apoC3 mRNA in patients with hypertriglyceridemia, including familial chylomicronemia syndrome (n = 3), volanesorsen monotherapy (n = 51), and as add-on to fibrate (n = 26), treated for 85 days and followed for 176 days. Compared with placebo, volanesorsen was associated with an 82.3 ± 11.7%, 81.3 ± 15.7%, and 80.8 ± 13.6% reduction in apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoA-I, respectively (300 mg dose;P< 0.001 for all), at day 92. Strong correlations in all assay measures were noted with total plasma apoC-III, chylomicron-apoC-III, and VLDL-apoC-III. In conclusion, novel high-throughput ELISAs were developed to detect lipoprotein-associated apoC-III, including for the first time on Lp(a). Volanesorsen uniformly lowers apoC-III on apoB-100, Lp(a), and apoA-I lipoproteins, and may be a potent agent to reduce triglycerides and cardiovascular risk mediated by apoC-III. Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.
Identifying root exudates in field contaminated soil systems
NASA Astrophysics Data System (ADS)
Rosenfeld, C.; Martinez, C. E.
2012-12-01
Carbon (C) compounds exuded from plant roots comprise a significant and reactive fraction of belowground C pools. These exudates substantially alter the soil directly surrounding plant roots and play a vital role in the global C cycle, soil ecology, and ecosystem mobility of both nutrients and contaminants. In soils, the solubility and bioavailability of metals such as iron, zinc, and cadmium are intricately linked to the quantity and chemical characteristics of the C compounds allocated to the soil by plants. Cadmium (Cd), a toxic heavy metal, forms stronger bonds with reduced S- and N-containing compounds than with carboxylic acids, which may influence exudate composition in hyperaccumulator and tolerant plants grown in Cd contaminated soils. We hypothesize that hyperaccumulator plants will exude a larger quantity of aromatic N and chelating di- and tri-carboxylic acid molecules, while plants that exclude heavy metals from uptake will exude a larger proportion of reduced S containing molecules. This study examines how a variety of techniques can measure the low concentrations of complex organic mixtures exuded by hyperaccumulator and non-hyperaccumulator plants grown in Cd-contaminated soils. Two congeneric plants, Thlaspi caerulescens (Ganges ecotype), and T. caerulescens (Prayon ecotype) were grown in 0.5 kg pots filled with Cd-contaminated field soils from Chicago, IL. Field soils were contaminated as a result of the application of contaminated biosolids in the 1960's and 1970's. Pots were fitted for rhizon soil moisture samplers, micro-lysimeters developed for in situ collection of small volumes in unsaturated soils, prior to planting. Plants were grown for 8 weeks before exudate collection. After the 8 weeks of growth, a pulse-chase isotope tracer method using the C stable isotope, 13C, was employed to differentiate plant-derived compounds from background soil and microbial-derived compounds. Plants were placed in a CO2 impermeable chamber, and the soil surface was covered by CO2 impermeable sheets to ensure that all 13C in the soil results from photoassimilated C released by roots and not soil-atmosphere gas exchange. Ambient CO2 was drawn down in the system until the CO2 concentration within the tent was less than 50 ppm, after which the labeled 13CO2 was introduced, returning the CO2 concentration to the ambient level (~375 ppm). The CO2 pulse lasted for 60 minutes to allow enough time for 13C assimilation within the plants. In order to determine the ideal sampling time, soil pore water samples were extracted every 1-2 hours following the 13C pulse application, over the course of 24 hours. Samples were analyzed for delta 13C as well as %C, and results indicate that the greatest plant-derived dissolved organic C is present at about 6 hours following the 13C pulse. A second experiment will also be conducted using a combination of NMR and mass spectrometry methods to obtain detailed information regarding chemical structures within exudate samples.
Jakobsen, Hans J; Bildsøe, Henrik; Skibsted, Jørgen; Brorson, Michael; Gor'kov, Peter; Gan, Zhehong
2010-02-01
A strategy, involving (i) sensitivity enhancement for the central transition (CT) by population transfer (PT) employing WURST inversion pulses to the satellite transitions (STs) in natural abundance (33)S MAS NMR for two different MAS frequencies (nu(r)=5.0 and 10.0kHz) at 14.1T and (ii) a (33)S static QCPMG experiment at 19.6T, has allowed acquisition and analysis of very complex solid-state (33)S CT NMR spectra for the disordered tetrathioperrhenate anion ReS(4)(-) in [(C(2)H(5))(4)N][ReS(4)]. This strategy of different NMR experiments combined with spectral analysis/simulations has allowed determination of precise values for two sets of quadrupole coupling parameters (C(Q) and eta(Q)) assigned to the two different S sites for the four sulfur atoms in the ReS(4)(-) anion in the ratio S1:S2=1:3. These sets of C(Q), eta(Q) values for the S1 and S2 site are quite similar and the magnitudes of the quadrupole coupling constants (C(Q)=2.2-2.5MHz) are a factor of about three larger than observed for other tetrathiometalates A(2)MS(4) (A=NH(4), Cs, Rb and M=W, Mo). In addition, the spectral analysis also leads to a determination of the chemical shift anisotropy (CSA) parameters (delta(sigma) and eta(sigma)) for the S1 and S2 site, however, with much lower precisions (about 20% error margins) compared to those for C(Q), eta(Q), because the magnitudes of the two CSAs (i.e., delta(sigma)=60-90ppm) are about a factor of six smaller than observed for the other tetrathiometalates mentioned above. This large difference in the magnitudes of the anisotropic parameters C(Q) and delta(sigma) for the ReS(4)(-) anion, compared to those for the WS(4)(2-) and MoS(4)(2-) anions determined previously under identical experimental conditions, accounts for the increased complexity of the PT-enhanced (33)S MAS spectra observed for the ReS(4)(-) anion in this study. This difference in C(Q) also contributes significantly to the intensity distortions observed in the outer wings of the CTs when employing PT from the STs under conditions of slow-speed MAS. Copyright 2009 Elsevier Inc. All rights reserved.
Bursaphelenchus xylophilus is killed by homologues of 2-(1-undecyloxy)-1-ethanol
NASA Astrophysics Data System (ADS)
Kim, Junheon; Lee, Sang-Myeong; Park, Chung Gyoo
2016-07-01
2-(1-Undecyloxy)-1-ethanol, monochamol, is a male-produced aggregation pheromone of the Monochamus species, which are efficient vectors of the pine wood nematode (PWN), Bursaphelenchus xylophilus, which cause devastating damage to pines worldwide. The nematicidal activity of synthetic monochamol and its homologues (ROEtOH: R = C7-C13) were investigated to find potential alternatives to the currently used PWN control agents abamectin and emamectin. Compounds with C7-C13 chain length alkyl groups exhibited 100% nematicidal activity at a concentration of 1000 mg/L. At a concentration of 100 mg/L, 2-(1-nonyloxy)-1-ethanol (C9OEtOH), 2-(1-decyloxy)-1-ethanol (C10OEtOH), 2-(1-undecyloxy)-1-ethanol (C11OEtOH), and 2-(1-dodecyloxy)-1-ethanol (C12OEtOH) showed 100% nematicidal activity, but the others showed weaker activities. C11OEtOH showed similar nematicidal activity to abamectin in terms of LD90 values, which were 13.30 and 12.53 mg/L, respectively. However, C9OEtOH, C10OEtOH, and C12OEtOH (LC90 values: 53.63, 38.18, and 46.68 mg/L, respectively) were less effective than C11OEtOH and abamectin. These results indicate that monochamol could be an effective alternative agent against PWN. The relationship of insecticidal and nematicidal activity to different carbon chain lengths in compounds is discussed.
Absolute parameters of young stars: QZ Carinae
NASA Astrophysics Data System (ADS)
Walker, W. S. G.; Blackford, M.; Butland, R.; Budding, E.
2017-09-01
New high-resolution spectroscopy and BVR photometry together with literature data on the complex massive quaternary star QZ Car are collected and analysed. Absolute parameters are found as follows. System A: M1 = 43 (±3), M2 = 19 (+3 -7), R1 = 28 (±2), R2 = 6 (±2), (⊙); T1 ˜ 28 000, T2 ˜ 33 000 K; System B: M1 = 30 (±3), M2 = 20 (±3), R1 = 10 (±0.5), R2 = 20 (±1), (⊙); T1 ˜ 36 000, T2 ˜ 30 000 K (model dependent temperatures). The wide system AB: Period = 49.5 (±1) yr, Epochs, conjunction = 1984.8 (±1), periastron = 2005.3 (±3) yr, mean separation = 65 (±3), (au); orbital inclination = 85 (+5 -15) deg, photometric distance ˜2700 (±300) pc, age = 4 (±1) Myr. Other new contributions concern: (a) analysis of the timing of minima differences (O - C)s for the eclipsing binary (System B); (b) the width of the eclipses, pointing to relatively large effects of radiation pressure; (c) inferences from the rotational widths of lines for both Systems A and B; and (d) implications for theoretical models of early-type stars. While feeling greater confidence on the quaternary's general parametrization, observational complications arising from strong wind interactions or other, unclear, causes still inhibit precision and call for continued multiwavelength observations. Our high-inclination value for the AB system helps to explain failures to resolve the wide binary in the previous years. The derived young age independently confirms membership of QZ Car to the open cluster Collinder 228.
Biodegradation kinetics were studied for binary and complex mixtures of nine polycyclic aromatic hydrocarbons (PAHs): naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, 2-ethylnaphthalene, phenanthrene, anthracene, pyrene, fluorene and fluoranthene. Discrepancies between the ...
Kazemi, Zahra; Amiri Rudbari, Hadi; Mirkhani, Valiollah; Sahihi, Mehdi; Moghadam, Majid; Tangestaninejad, Shahram; Mohammadpoor-Baltork, Iraj; Kajani, Abolghasem Abbasi; Azimi, Gholamhassan
2017-07-28
The reaction of a racemic mixture of Schiff base tridentate ligand with vanadium(V) affords homochiral vanadium complex, (VO(R-L)) 2 O and (VO(S-L)) 2 O due to ligand "self-recognition" process. The formation of homochiral vanadium complex was confirmed by 1 H NMR, 13 C NMR and X-ray diffraction. The HSA- and DNA-binding of the resultant complex is assessed by absorption, fluorescence and circular dichroism (CD) spectroscopy methods. Based on the results, the HSA- and DNA-binding constant, K b , were found to be 8.0 × 10 4 and 1.9 × 10 5 M -1 , respectively. Interestingly, in vitro cytotoxicity assay revealed the potent anticancer activity of this complex on two prevalent cancer cell lines of MCF-7 (IC50 value of 14 μM) and HeLa (IC50 value of 36 μM), with considerably low toxicity on normal human fibroblast cells. The maximum cell mortality of 12.3% obtained after 48 h incubation of fibroblast cells with 100 μM of the complex. Additionally, the specific DNA- and HSA-binding was also shown using molecular docking method. The synthesized complex displayed high potential for biomedical applications especially for development of novel and efficient anticancer agents. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Theoretical and Computational Studies of Stability, Transition and Flow Control in High-Speed Flows
2011-02-22
A. H. Nayfeh. Nonparallel stability of boundary layers with pressure gradients and suction. Technical Report AGARD - CP -224, 1977. [Squ33] H. B. Squire...only. µ = µr ( T Tr )3/2 Tr + Ts T + Ts , (2.13) 8 K = µcp Pr , (2.14) where µr = 1.7894 × 10−5 Ns/m2, Tr = 288.0 K, Ts = 110.33 K, and cp is the...fraction of species s Cpf = frozen specific heat, cal/g-mole-K Cp ,s = specific heat at constant pressure of species s, cal/g-mole Dij = binary diffusion
Highly stable and regenerable Mn-based/SBA-15 sorbents for desulfurization of hot coal gas.
Zhang, F M; Liu, B S; Zhang, Y; Guo, Y H; Wan, Z Y; Subhan, Fazle
2012-09-30
A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700-850°C. The successive nine desulfurization-regeneration cycles at 800°C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn(2)O(3) particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800°C is 13.8 g S/100g sorbents, which is remarkably higher than these of 40 wt%LaFeO(3)/SBA-15 (4.8 g S/100g sorbents) and 50 wt%LaFe(2)O(x)/MCM-41 (5.58 g S/100g sorbents) used only at 500-550°C. This suggested that the loading of Mn(2)O(3) active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization. Copyright © 2012 Elsevier B.V. All rights reserved.
78 FR 46256 - Scope and Definitions (2 U.S.C. 431)
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-31
... FEDERAL ELECTION COMMISSION 11 CFR Part 100 Scope and Definitions (2 U.S.C. 431) CFR Correction In Title 11 of the Code of Federal Regulations, revised as of January 1, 2012, on page 42, in Sec. 100.19, a heading is added to paragraph (a) to read as follows: Sec. 100.19 File, filed or filing (2 U.S.C...
NASA Astrophysics Data System (ADS)
Li, Jili; Wang, Xiaofeng; Zhao, Junwei; Chen, Jian; Jia, Tiekun; Cao, Chuanbao
2016-03-01
Novel 2D LiNi1/3Co1/3Mn1/3O2 hierarchical nanosheets are successfully synthesized through a simple sol-gel strategy with ethanol dispersion of carbon nanotubes as addictive. The nanosheets with thickness of ∼100 nm appear porous and are formed by 100 nm nanoparticles. As cathode for lithium ion battery, the 2D porous hierarchical nanosheets demonstrate high specific capacity of 137.7 mAh g-1 at 20C (1C = 200 mA g-1), which is much higher than those of its counterparts. The high capacity can be still maintained during 100 charge/discharge cycles and the capacity retention is up to 90.1%. The excellent rate capability and cyclability may be attributed to the distinct 2D porous hierarchical structure.
Structural Basis for Inhibition of Mammalian Adenylyl Cyclase by Calcium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mou, Tung-Chung; Masada, Nanako; Cooper, Dermot M.F.
2009-09-11
Type V and VI mammalian adenylyl cyclases (AC5, AC6) are inhibited by Ca{sup 2+} at both sub- and supramicromolar concentration. This inhibition may provide feedback in situations where cAMP promotes opening of Ca{sup 2+} channels, allowing fine control of cardiac contraction and rhythmicity in cardiac tissue where AC5 and AC6 predominate. Ca{sup 2+} inhibits the soluble AC core composed of the C1 domain of AC5 (VC1) and the C2 domain of AC2 (IIC2). As observed for holo-AC5, inhibition is biphasic, showing 'high-affinity' (K{sub i} = {approx}0.4 {mu}M) and 'low-affinity' (K{sub i} = {approx}100 {mu}M) modes of inhibition. At micromolar concentration,more » Ca{sup 2+} inhibition is nonexclusive with respect to pyrophosphate (PP{sub i}), a noncompetitive inhibitor with respect to ATP, but at >100 {mu}M Ca{sup 2+}, inhibition appears to be exclusive with respect to PP{sub i}. The 3.0 {angstrom} resolution structure of G{alpha}s{center_dot}GTP{gamma}S/forskolin-activated VC1:IIC2 crystals soaked in the presence of ATP{alpha}S and 8 {mu}M free Ca{sup 2+} contains a single, loosely coordinated metal ion. ATP soaked into VC1:IIC2 crystals in the presence of 1.5 mM Ca{sup 2+} is not cyclized, and two calcium ions are observed in the 2.9 {angstrom} resolution structure of the complex. In both of the latter complexes VC1:IIC2 adopts the 'open', catalytically inactive conformation characteristic of the apoenzyme, in contrast to the 'closed', active conformation seen in the presence of ATP analogues and Mg{sup 2+} or Mn{sup 2+}. Structures of the pyrophosphate (PP{sub i}) complex with 10 mM Mg{sup 2+} (2.8 {angstrom}) or 2 mM Ca{sup 2+} (2.7 {angstrom}) also adopt the open conformation, indicating that the closed to open transition occurs after cAMP release. In the latter complexes, Ca{sup 2+} and Mg{sup 2+} bind only to the high-affinity 'B' metal site associated with substrate/product stabilization. Ca{sup 2+} thus stabilizes the inactive conformation in both ATP- and PP{sub i}-bound states.« less
NASA Astrophysics Data System (ADS)
Aita, M. N.; Minoru, K.; Kobari, T.; Yoshikawa, C.; Ishii, R.
2016-02-01
Carbon and nitrogen isotope ratios of biota are controlled by two factors, a metabolic system and a lifestyle of predator and a regional variability of environmental parameters on food web system. To evaluate the environmental factors (i.e., nutrients and temperature) on the basic food web in the marine ecosystem. We studied the seasonal variation of nitrogen and carbon isotope ratios of zooplankton in the subarctic site of K2 (47ºN, 160ºE) and the subtropical one of S1 (30ºN, 145ºE) in the western North Pacific Ocean, both of which are JAMSTEC observation site. Biota were collected in eight depths (0-50, 50-100, 100-150, 150-200, 200-300, 300-500, 500-750, 750-1000m) at both sites using IONESS from February 2010 to July 2011. All samples were classified under a stereomicroscope into species or genus level and used adult stage for isotopic analysis. We also collected water samples from seasonal and vertical (from the surface to 1,000m depth) profiles in δ15N (NO3+ + NO2-) at K2 and S1 in special reference to nitrogen cycles. The δ15N and δ13C values of amphipods and copepod, omnivorous zooplankton in the surface ocean, showed a large seasonal variation. The δ15N values of zooplankton and nitrate ions in the water at the S1 site tended to be lower than those at the K2 site, indicating that the basic food web could be affected by nitrogen fixation. We further compared the trophic fractionation of carbon and nitrogen isotopes (Δδ13C, Δδ15N). It was observed that a simple relationship exists in the Δδ15N/Δδ13C regardless of species and ecosystems. This contention suggests a unified regularity is maintained in the lower to higher trophic level in the marine ecosystem.
Ghosh, Chiranjit; Maity, Abhijit; Banik, Gourab D; Som, Suman; Chakraborty, Arpita; Selvan, Chitra; Ghosh, Shibendu; Ghosh, Barnali; Chowdhury, Subhankar; Pradhan, Manik
2014-09-01
We report, for the first time, the clinical feasibility of a novel residual gas analyzer mass spectrometry (RGA-MS) method for accurate evaluation of the (13)C-glucose breath test ((13)C-GBT) in the diagnosis of pre-diabetes (PD) and type 2 diabetes mellitus (T2D). In T2D or PD, glucose uptake is impaired and results in blunted isotope enriched (13)CO2 production in exhaled breath samples. Using the Receiver operating characteristics (ROC) curve analysis, an optimal diagnostic cut-off point of the (13)CO2/(12)CO2 isotope ratios expressed as the delta-over-baseline (DOB) value, was determined to be δDOB(13)C‰ = 28.81‰ for screening individuals with non-diabetes controls (NDC) and pre-diabetes (PD), corresponding to a sensitivity of 100% and specificity of 94.4%. We also determined another optimal diagnostic cut-off point of δDOB(13)C‰ = 19.88‰ between individuals with PD and T2D, which exhibited 100% sensitivity and 95.5% specificity. Our RGA-MS methodology for the (13)C-GBT also manifested a typical diagnostic positive and negative predictive value of 96% and 100%, respectively. The diagnostic accuracy, precision and validity of the results were also confirmed by high-resolution optical cavity enhanced integrated cavity output spectroscopy (ICOS) measurements. The δDOB(13)C‰ values measured with RGA-MS method, correlated favourably (R(2) = 0.979) with those determined by the laser based ICOS method. Moreover, we observed that the effects of endogenous CO2 production related to basal metabolic rates in individuals were statistically insignificant (p = 0.37 and 0.73) on the diagnostic accuracy. Our findings suggest that the RGA-MS is a valid and sufficiently robust method for the (13)C-GBT which may serve as an alternative non-invasive point-of-care diagnostic tool for routine clinical practices as well as for large-scale diabetes screening purposes in real-time.
NASA Astrophysics Data System (ADS)
Abadie, J.; Abbott, B. P.; Abbott, R.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Ajith, P.; Allen, B.; Allen, G.; Amador Ceron, E.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Antonucci, F.; Aoudia, S.; Arain, M. A.; Araya, M.; Aronsson, M.; Arun, K. G.; Aso, Y.; Aston, S.; Astone, P.; Atkinson, D. E.; Aufmuth, P.; Aulbert, C.; Babak, S.; Baker, P.; Ballardin, G.; Ballmer, S.; Barker, D.; Barnum, S.; Barone, F.; Barr, B.; Barriga, P.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Bauchrowitz, J.; Bauer, Th S.; Behnke, B.; Beker, M. G.; Belczynski, K.; Benacquista, M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bigotta, S.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birindelli, S.; Biswas, R.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Blom, M.; Blomberg, A.; Boccara, C.; Bock, O.; Bodiya, T. P.; Bondarescu, R.; Bondu, F.; Bonelli, L.; Bork, R.; Born, M.; Bose, S.; Bosi, L.; Boyle, M.; Braccini, S.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Brau, J. E.; Breyer, J.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Budzyński, R.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burguet-Castell, J.; Burmeister, O.; Buskulic, D.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calloni, E.; Camp, J. B.; Campagna, E.; Campsie, P.; Cannizzo, J.; Cannon, K. C.; Canuel, B.; Cao, J.; Capano, C.; Carbognani, F.; Caride, S.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarini, E.; Chalermsongsak, T.; Chalkley, E.; Charlton, P.; Chassande Mottin, E.; Chelkowski, S.; Chen, Y.; Chincarini, A.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Clark, D.; Clark, J.; Clayton, J. H.; Cleva, F.; Coccia, E.; Colacino, C. N.; Colas, J.; Colla, A.; Colombini, M.; Conte, R.; Cook, D.; Corbitt, T. R.; Corda, C.; Cornish, N.; Corsi, A.; Costa, C. A.; Coulon, J. P.; Coward, D.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Culter, R. M.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; D'Antonio, S.; Danzmann, K.; Dari, A.; Das, K.; Dattilo, V.; Daudert, B.; Davier, M.; Davies, G.; Davis, A.; Daw, E. J.; Day, R.; Dayanga, T.; De Rosa, R.; DeBra, D.; Degallaix, J.; del Prete, M.; Dergachev, V.; DeRosa, R.; DeSalvo, R.; Devanka, P.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Emilio, M. Di Paolo; Di Virgilio, A.; Díaz, M.; Dietz, A.; Donovan, F.; Dooley, K. L.; Doomes, E. E.; Dorsher, S.; Douglas, E. S. D.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Dueck, J.; Dumas, J. C.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Engel, R.; Etzel, T.; Evans, M.; Evans, T.; Fafone, V.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Ferrante, I.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Flaminio, R.; Flanigan, M.; Flasch, K.; Foley, S.; Forrest, C.; Forsi, E.; Fotopoulos, N.; Fournier, J. D.; Franc, J.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gammaitoni, L.; Garofoli, J. A.; Garufi, F.; Gemme, G.; Genin, E.; Gennai, A.; Gholami, I.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gill, C.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Gouaty, R.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Greverie, C.; Grosso, R.; Grote, H.; Grunewald, S.; Guidi, G. M.; Gustafson, E. K.; Gustafson, R.; Hage, B.; Hall, P.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Haughian, K.; Hayama, K.; Heefner, J.; Heitmann, H.; Hello, P.; Heng, I. S.; Heptonstall, A.; Hewitson, M.; Hild, S.; Hirose, E.; Hoak, D.; Hodge, K. A.; Holt, K.; Hosken, D. J.; Hough, J.; Howell, E.; Hoyland, D.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Jaranowski, P.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kandhasamy, S.; Kanner, J.; Katsavounidis, E.; Kawabe, K.; Kawamura, S.; Kawazoe, F.; Kells, W.; Keppel, D. G.; Khalaidovski, A.; Khalili, F. Y.; Khazanov, E. A.; Kim, C.; Kim, H.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Klimenko, S.; Kondrashov, V.; Kopparapu, R.; Koranda, S.; Kowalska, I.; Kozak, D.; Krause, T.; Kringel, V.; Krishnamurthy, S.; Krishnan, B.; Królak, A.; Kuehn, G.; Kullman, J.; Kumar, R.; Kwee, P.; Landry, M.; Lang, M.; Lantz, B.; Lastzka, N.; Lazzarini, A.; Leaci, P.; Leong, J.; Leonor, I.; Leroy, N.; Letendre, N.; Li, J.; Li, T. G. F.; Lin, H.; Lindquist, P. E.; Lockerbie, N. A.; Lodhia, D.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lu, P.; Luan, J.; Lubiński, M.; Lucianetti, A.; Lück, H.; Lundgren, A.; Machenschalk, B.; MacInnis, M.; Mackowski, J. M.; Mageswaran, M.; Mailand, K.; Majorana, E.; Mak, C.; Man, N.; Mandel, I.; Mandic, V.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Maros, E.; Marque, J.; Martelli, F.; Martin, I. W.; Martin, R. M.; Marx, J. N.; Mason, K.; Masserot, A.; Matichard, F.; Matone, L.; Matzner, R. A.; Mavalvala, N.; McCarthy, R.; McClelland, D. E.; McGuire, S. C.; McIntyre, G.; McIvor, G.; McKechan, D. J. A.; Meadors, G.; Mehmet, M.; Meier, T.; Melatos, A.; Melissinos, A. C.; Mendell, G.; Menéndez, D. F.; Mercer, R. A.; Merill, L.; Meshkov, S.; Messenger, C.; Meyer, M. S.; Miao, H.; Michel, C.; Milano, L.; Miller, J.; Minenkov, Y.; Mino, Y.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moe, B.; Mohan, M.; Mohanty, S. D.; Mohapatra, S. R. P.; Moraru, D.; Moreau, J.; Moreno, G.; Morgado, N.; Morgia, A.; Morioka, T.; Mors, K.; Mosca, S.; Moscatelli, V.; Mossavi, K.; Mours, B.; MowLowry, C.; Mueller, G.; Mukherjee, S.; Mullavey, A.; Müller-Ebhardt, H.; Munch, J.; Murray, P. G.; Nash, T.; Nawrodt, R.; Nelson, J.; Neri, I.; Newton, G.; Nishizawa, A.; Nocera, F.; Nolting, D.; Ochsner, E.; O'Dell, J.; Ogin, G. H.; Oldenburg, R. G.; O'Reilly, B.; O'Shaughnessy, R.; Osthelder, C.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Page, A.; Pagliaroli, G.; Palladino, L.; Palomba, C.; Pan, Y.; Pankow, C.; Paoletti, F.; Papa, M. A.; Pardi, S.; Pareja, M.; Parisi, M.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patel, P.; Pedraza, M.; Pekowsky, L.; Penn, S.; Peralta, C.; Perreca, A.; Persichetti, G.; Pichot, M.; Pickenpack, M.; Piergiovanni, F.; Pietka, M.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Pletsch, H. J.; Plissi, M. V.; Poggiani, R.; Postiglione, F.; Prato, M.; Predoi, V.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Quetschke, V.; Raab, F. J.; Rabaste, O.; Rabeling, D. S.; Radke, T.; Radkins, H.; Raffai, P.; Rakhmanov, M.; Rankins, B.; Rapagnani, P.; Raymond, V.; Re, V.; Reed, C. M.; Reed, T.; Regimbau, T.; Reid, S.; Reitze, D. H.; Ricci, F.; Riesen, R.; Riles, K.; Roberts, P.; Robertson, N. A.; Robinet, F.; Robinson, C.; Robinson, E. L.; Rocchi, A.; Roddy, S.; Röver, C.; Rogstad, S.; Rolland, L.; Rollins, J.; Romano, J. D.; Romano, R.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sakata, S.; Sakosky, M.; Salemi, F.; Sammut, L.; Sancho de la Jordana, L.; Sandberg, V.; Sannibale, V.; Santamaría, L.; Santostasi, G.; Saraf, S.; Sassolas, B.; Sathyaprakash, B. S.; Sato, S.; Satterthwaite, M.; Saulson, P. R.; Savage, R.; Schilling, R.; Schnabel, R.; Schofield, R.; Schulz, B.; Schutz, B. F.; Schwinberg, P.; Scott, J.; Scott, S. M.; Searle, A. C.; Seifert, F.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sergeev, A.; Shaddock, D. A.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sibley, A.; Siemens, X.; Sigg, D.; Singer, A.; Sintes, A. M.; Skelton, G.; Slagmolen, B. J. J.; Slutsky, J.; Smith, J. R.; Smith, M. R.; Smith, N. D.; Somiya, K.; Sorazu, B.; Speirits, F. C.; Stein, A. J.; Stein, L. C.; Steinlechner, S.; Steplewski, S.; Stochino, A.; Stone, R.; Strain, K. A.; Strigin, S.; Stroeer, A.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sung, M.; Susmithan, S.; Sutton, P. J.; Swinkels, B.; Talukder, D.; Tanner, D. B.; Tarabrin, S. P.; Taylor, J. R.; Taylor, R.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Thüring, A.; Titsler, C.; Tokmakov, K. V.; Toncelli, A.; Tonelli, M.; Torres, C.; Torrie, C. I.; Tournefier, E.; Travasso, F.; Traylor, G.; Trias, M.; Trummer, J.; Tseng, K.; Ugolini, D.; Urbanek, K.; Vahlbruch, H.; Vaishnav, B.; Vajente, G.; Vallisneri, M.; van den Brand, J. F. J.; Van Den Broeck, C.; van der Putten, S.; van der Sluys, M. V.; van Veggel, A. A.; Vass, S.; Vaulin, R.; Vavoulidis, M.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Veltkamp, C.; Verkindt, D.; Vetrano, F.; Viceré, A.; Villar, A.; Vinet, J.-Y.; Vocca, H.; Vorvick, C.; Vyachanin, S. P.; Waldman, S. J.; Wallace, L.; Wanner, A.; Ward, R. L.; Was, M.; Wei, P.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Wen, S.; Wessels, P.; West, M.; Westphal, T.; Wette, K.; Whelan, J. T.; Whitcomb, S. E.; White, D. J.; Whiting, B. F.; Wilkinson, C.; Willems, P. A.; Williams, L.; Willke, B.; Winkelmann, L.; Winkler, W.; Wipf, C. C.; Wiseman, A. G.; Woan, G.; Wooley, R.; Worden, J.; Yakushin, I.; Yamamoto, H.; Yamamoto, K.; Yeaton-Massey, D.; Yoshida, S.; Yu, P. P.; Yvert, M.; Zanolin, M.; Zhang, L.; Zhang, Z.; Zhao, C.; Zotov, N.; Zucker, M. E.; Zweizig, J.; LIGO Scientific Collaboration; Virgo Collaboration
2010-09-01
We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo. Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters and are still uncertain. The most confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our galaxy. These yield a likely coalescence rate of 100 Myr-1 per Milky Way Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 Myr-1 MWEG-1 to 1000 Myr-1 MWEG-1 (Kalogera et al 2004 Astrophys. J. 601 L179; Kalogera et al 2004 Astrophys. J. 614 L137 (erratum)). We convert coalescence rates into detection rates based on data from the LIGO S5 and Virgo VSR2 science runs and projected sensitivities for our advanced detectors. Using the detector sensitivities derived from these data, we find a likely detection rate of 0.02 per year for Initial LIGO-Virgo interferometers, with a plausible range between 2 × 10-4 and 0.2 per year. The likely binary neutron-star detection rate for the Advanced LIGO-Virgo network increases to 40 events per year, with a range between 0.4 and 400 per year.
Wang, Liqun; Luo, Haihua; Chen, Xiaohuan; Jiang, Yong; Huang, Qiaobing
2014-01-01
S100A8, S100A9 and S100A8/A9 complexes have been known as important endogenous damage-associated molecular pattern (DAMP) proteins. But the pathophysiological roles of S100A8, S100A9 and S100A8/A9 in cardiovascular diseases are incompletely explained. In this present study, the effects of homo S100A8, S100A9 and their hetero-complex S100A8/A9 on endothelial barrier function were tested respectively in cultured human umbilical venous endothelial cells (HUVECs). The involvement of TLR4 and RAGE were observed by using inhibitor of TLR4 and blocking antibody of RAGE. The clarification of different MAPK subtypes in S100A8/A9-induced endothelial response was implemented by using specific inhibitors. The calcium-dependency was detected in the absence of Ca2+ or in the presence of gradient-dose Ca2+. The results showed that S100A8, S100A9 and S100A8/A9 could induce F-actin and ZO-1 disorganization in HUVECs and evoked the increases of HUVEC monolayer permeability in a dose- and time-dependent manner. The effects of S100A8, S100A9 and S100A8/A9 on endothelial barrier function depended on the activation of p38 and ERK1/2 signal pathways through receptors TLR4 and RAGE. Most importantly, we revealed the preference of S100A8 on TLR4 and S100A9 on RAGE in HUVECs. The results also showed the calcium dependency in S100A8- and S100A9-evoked endothelial response, indicating that calcium dependency on formation of S100A8 or A9 dimmers might be the prerequisite for this endothelial functional alteration. PMID:24595267
Cesena, Fernando Henpin Yue; Laurinavicius, Antonio Gabriele; Valente, Viviane A; Conceição, Raquel D; Santos, Raul D; Bittencourt, Marcio S
2017-06-01
There is controversy whether management of blood cholesterol should be based or not on LDL-cholesterol (LDL-c) target concentrations. To compare the estimated impact of different lipid-lowering strategies, based or not on LDL-c targets, on the risk of major cardiovascular events in a population with higher cardiovascular risk. We included consecutive individuals undergoing a routine health screening in a single center who had a 10-year risk for atherosclerotic cardiovascular disease (ASCVD) ≥ 7.5% (pooled cohort equations, ACC/AHA, 2013). For each individual, we simulated two strategies based on LDL-c target (≤ 100 mg/dL [Starget-100] or ≤ 70 mg/dL [Starget-70]) and two strategies based on percent LDL-c reduction (30% [S30%] or 50% [S50%]). In 1,897 subjects (57 ± 7 years, 96% men, 10-year ASCVD risk 13.7 ± 7.1%), LDL-c would be lowered from 141 ± 33 mg/dL to 99 ± 23 mg/dL in S30%, 71 ± 16 mg/dL in S50%, 98 ± 9 mg/dL in Starget-100, and 70 ± 2 mg/dL in Starget-70. Ten-year ASCVD risk would be reduced to 8.8 ± 4.8% in S50% and 8.9 ± 5.2 in Starget-70. The number of major cardiovascular events prevented in 10 years per 1,000 individuals would be 32 in S30%, 31 in Starget-100, 49 in S50%, and 48 in Starget-70. Compared with Starget-70, S50% would prevent more events in the lower LDL-c tertile and fewer events in the higher LDL-c tertile. The more aggressive lipid-lowering approaches simulated in this study, based on LDL-c target or percent reduction, may potentially prevent approximately 50% more hard cardiovascular events in the population compared with the less intensive treatments. Baseline LDL-c determines which strategy (based or not on LDL-c target) is more appropriate at the individual level. Há controvérsias sobre se o controle do colesterol plasmático deve ou não se basear em metas de concentração de colesterol LDL (LDL-c). Comparar o impacto estimado de diferentes estratégias hipolipemiantes, baseadas ou não em metas de LDL-c, sobre o risco de eventos cardiovasculares maiores em uma população de risco cardiovascular mais elevado. Foram incluídos indivíduos consecutivamente submetidos a uma avaliação rotineira de saúde em um único centro e que apresentavam um risco em 10 anos de doença cardiovascular aterosclerótica (DCVAS) ≥ 7,5% ("pooled cohort equations", ACC/AHA, 2013). Para cada indivíduo, foram simuladas duas estratégias baseadas em meta de LDL-c (≤ 100 mg/dL [Emeta-100] ou ≤ 70 mg/dL [Emeta-70]) e duas estratégias baseadas em redução percentual do LDL-c (30% [E30%] ou 50% [E50%]). Em 1.897 indivíduos (57 ± 7 anos, 96% homens, risco em 10 anos de DCVAS 13,7 ± 7,1%), o LDL-c seria reduzido de 141 ± 33 mg/dL para 99 ± 23 mg/dL na E30%, 71 ± 16 mg/dL na E50%, 98 ± 9 mg/dL na Emeta-100 e 70 ± 2 mg/dL na Emeta-70. O risco em 10 anos de DCVAS seria reduzido para 8,8 ± 4,8% na E50% e para 8,9 ± 5,2 na Emeta-70. O número de eventos cardiovasculares maiores prevenidos em 10 anos por 1.000 indivíduos seria de 32 na E30%, 31 na Emeta-100, 49 na E50% e 48 na Emeta-70. Em comparação com a Emeta-70, a E50% evitaria mais eventos no tercil inferior de LDL-c e menos eventos no tercil superior de LDL-c. As abordagens hipolipemiantes mais agressivas simuladas neste estudo, com base em meta de LDL-c ou redução percentual, podem potencialmente prevenir cerca de 50% mais eventos cardiovasculares graves na população em comparação com os tratamentos menos intensivos. Os níveis basais de LDL-c determinam qual estratégia (baseada ou não em meta de LDL-c) é mais apropriada para cada indivíduo.
Epitope mapping of anti-interleukin-13 neutralizing antibody CNTO607.
Teplyakov, Alexey; Obmolova, Galina; Wu, Sheng-Jiun; Luo, Jinquan; Kang, James; O'Neil, Karyn; Gilliland, Gary L
2009-05-29
CNTO607 is a neutralizing anti-interleukin-13 (IL-13) human monoclonal antibody obtained from a phage display library. To determine how this antibody inhibits the biological effect of IL-13, we determined the binding epitope by X-ray crystallography. The crystal structure of the complex between CNTO607 Fab and IL-13 reveals the antibody epitope at the surface formed by helices A and D of IL-13. This epitope overlaps with the IL-4Ralpha/IL-13Ralpha1 receptor-binding site, which explains the neutralizing effect of CNTO607. The extensive antibody interface covers an area of 1000 A(2), which is consistent with the high binding affinity. The key features of the interface are the charge and shape complementarity of the molecules that include two hydrophobic pockets on IL-13 that accommodate Phe32 [complementarity-determining region (CDR) L2] and Trp100a (CDR H3) and a number of salt bridges between basic residues of IL-13 and acidic residues of the antibody. Comparison with the structure of the free Fab shows that the CDR residues do not change their conformation upon complex formation, with the exception of two residues in CDR H3, Trp100a and Asp100b, which change rotamer conformations. To evaluate the relative contribution of the epitope residues to CNTO607 binding, we performed alanine-scanning mutagenesis of the A-D region of IL-13. This study confirmed the primary role of electrostatic interactions for antigen recognition.
Optical Neural Classification Of Binary Patterns
NASA Astrophysics Data System (ADS)
Gustafson, Steven C.; Little, Gordon R.
1988-05-01
Binary pattern classification that may be implemented using optical hardware and neural network algorithms is considered. Pattern classification problems that have no concise description (as in classifying handwritten characters) or no concise computation (as in NP-complete problems) are expected to be particularly amenable to this approach. For example, optical processors that efficiently classify binary patterns in accordance with their Boolean function complexity might be designed. As a candidate for such a design, an optical neural network model is discussed that is designed for binary pattern classification and that consists of an optical resonator with a dynamic multiplex-recorded reflection hologram and a phase conjugate mirror with thresholding and gain. In this model, learning or training examples of binary patterns may be recorded on the hologram such that one bit in each pattern marks the pattern class. Any input pattern, including one with an unknown class or marker bit, will be modified by a large number of parallel interactions with the reflection hologram and nonlinear mirror. After perhaps several seconds and 100 billion interactions, a steady-state pattern may develop with a marker bit that represents a minimum-Boolean-complexity classification of the input pattern. Computer simulations are presented that illustrate progress in understanding the behavior of this model and in developing a processor design that could have commanding and enduring performance advantages compared to current pattern classification techniques.
Magnetic Behavior of a Dy8 Molecular Nanomagnet
NASA Astrophysics Data System (ADS)
Zhang, Qing; Sarachik, Myriam; Baker, Michael; Chen, Yizhang; Kent, Andrew; Stamatatos, Theocharis
2015-03-01
As part of a study of quantum tunneling in a newly synthesized family of dysprosium-based molecular magnets that exhibit a chiral spin structure, we report initial investigations of the magnetic response of a Dy8 cluster with the formula (Et4N)4[Dy8O(nd)8(NO3)10(H2O)2] .2MeCN. The molecular complex contains triangular arrangements of exchange coupled Dy(III) ions. The compound forms an approximate snub-square Archimedean lattice unit. The measured magnetization of this network of four triangles suggests the presence of multiple spin chiral vortexes. Single crystal susceptibility and magnetization measurements indicate the presence of a hard-axis direction and an easy plane. These principal orientations have been investigated in magnetic fields up to 5 Tesla for temperatures between 1.8 and 100 K using a SQUID-based Quantum Design MPMS magnetometer. Complex easy plane magnetic hysteresis loops emerge at lower temperatures measured using Hall probe magnetometry at sub 1 K temperatures. The analysis of these measurements will be discussed and compared with results of theoretical calculations. Work supported by ARO W911NF-13-1-1025 (CCNY), NSF-DMR-1309202 (NYU); the synthesis of the Dy8 cluster was supported by NSERC (Discovery grant to Th.C.S.).
NASA Astrophysics Data System (ADS)
Morishita, Hidetada; Tamiaki, Hitoshi
2009-03-01
Metal complexes of methyl 13 1- 18O-labelled pyropheophorbide- a1-M- 18O (M = Zn, Cu and Ni) were prepared by metallation of the 18O-labelled free base ( 1- 18O) and 18O-labelling of unlabelled nickel complex ( 1-Ni). The FT-IR spectra of 1-Zn and 1-Zn- 18O in CH 2Cl 2 showed that the 13-keto carbonyl stretching vibration mode moved to about a 30-cm -1 lower wavenumber by 18O-labelling of the 13 1-oxo moiety. In 1-Cu- 18O and 1-Ni- 18O, the 13-C dbnd 18O stretching modes were close to the highest-energy wavenumber mode of chlorin skeletal C-C/C-N vibrations at around 1650 cm -1 and they were coupled in CH 2Cl 2 to give two split IR bands (Fermi resonance). A similar coupling was observed in the resonance Raman scattering of 1-Ni- 18O in the solid state. The hydrogen-bonded 13-C dbnd 16O vibration mode of 1-Ni similarly coupled with the skeletal C-C/C-N mode in CCl 4 containing 1% (v/v) 1,1,1,3,3,3-hexafluoro-2-propanol, while such a coupling was not observed in a neat CCl 4 solution of 1-Ni possessing the 13-C dbnd 16O free from any interaction. The skeletal C-C/C-N band selectively coupled with the 13-C dbnd O, not with the 3-C dbnd O, when the difference in their peak maxima was less than 20 cm -1.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ben Smida, Youssef; Marzouki, Riadh; Georges, Samuel
A new sodium cobalt (II) arsenate Na{sub 4}Co{sub 7}(AsO{sub 4}){sub 6} has been synthesized by a solid-state reaction and its crystal structure determined from single crystal X-ray diffraction data. It crystallizes in the monoclinic system, space group C2/m, with a=10.7098(9) Å, b=14.7837(9) Å, c=6.6845(7) Å, and β=105.545(9)°. The structure is described as a three-dimensional framework built up of corner-edge sharing CoO{sub 6}, CoO{sub 4} and AsO{sub 4} polyhedra, with interconnecting channels along [100] in which the Na{sup +} cations are located. The densest ceramics with relative density of 94% was obtained by ball milling and optimization of sintering temperature, andmore » its microstructure characterized by scanning electron microscopy. The electrical properties of the ceramics were studied over a temperature interval from 280 °C to 560 °C using the complex impedance spectroscopy over the range of 13 MHz–5 Hz. The ionic bulk conductivity value of the sample at 360 °C is 2.51 10{sup −5} S cm{sup −1} and the measured activation energy is Ea=1 eV. The sodium migration pathways in the crystal structure were investigated computationally using the bond valence site energy (BVSE) model and classical molecular dynamics (MD) simulations. - Graphical abstract: Correlation between crystal structure, microstructure and ionic conductivity . Display Omitted - Highlights: • A new arsenate Na{sub 4}Co{sub 7}(AsO{sub 4}){sub 6} was prepared by solid state reaction. • Its crystal structure was determined by powder X-ray diffraction. • Na{sup +} ionic conductivity was probed by complex impedance spectroscopy. • Na{sup +} conduction pathways were modeled by bond-valence method and molecular dynamics.« less
Accuracy of binary black hole waveform models for aligned-spin binaries
NASA Astrophysics Data System (ADS)
Kumar, Prayush; Chu, Tony; Fong, Heather; Pfeiffer, Harald P.; Boyle, Michael; Hemberger, Daniel A.; Kidder, Lawrence E.; Scheel, Mark A.; Szilagyi, Bela
2016-05-01
Coalescing binary black holes are among the primary science targets for second generation ground-based gravitational wave detectors. Reliable gravitational waveform models are central to detection of such systems and subsequent parameter estimation. This paper performs a comprehensive analysis of the accuracy of recent waveform models for binary black holes with aligned spins, utilizing a new set of 84 high-accuracy numerical relativity simulations. Our analysis covers comparable mass binaries (mass-ratio 1 ≤q ≤3 ), and samples independently both black hole spins up to a dimensionless spin magnitude of 0.9 for equal-mass binaries and 0.85 for unequal mass binaries. Furthermore, we focus on the high-mass regime (total mass ≳50 M⊙ ). The two most recent waveform models considered (PhenomD and SEOBNRv2) both perform very well for signal detection, losing less than 0.5% of the recoverable signal-to-noise ratio ρ , except that SEOBNRv2's efficiency drops slightly for both black hole spins aligned at large magnitude. For parameter estimation, modeling inaccuracies of the SEOBNRv2 model are found to be smaller than systematic uncertainties for moderately strong GW events up to roughly ρ ≲15 . PhenomD's modeling errors are found to be smaller than SEOBNRv2's, and are generally irrelevant for ρ ≲20 . Both models' accuracy deteriorates with increased mass ratio, and when at least one black hole spin is large and aligned. The SEOBNRv2 model shows a pronounced disagreement with the numerical relativity simulation in the merger phase, for unequal masses and simultaneously both black hole spins very large and aligned. Two older waveform models (PhenomC and SEOBNRv1) are found to be distinctly less accurate than the more recent PhenomD and SEOBNRv2 models. Finally, we quantify the bias expected from all four waveform models during parameter estimation for several recovered binary parameters: chirp mass, mass ratio, and effective spin.
Brooke, L.T.
1975-01-01
Eggs of lake whitefish (Coregonus clupeaformis) were incubated in a constant-flow incubator at constant temperatures of 0.5, 2.0, 4.0, 5.9, 7.8, and 10.0 C. The time from fertilization to median hatch was inversely related to temperature, and ranged from 41.7 days at 10.0 C to 182 days at 0.5 C. The percentage hatch was highest (70.9-73.3%) at 4.0, 5.9, and 7.8 C, and was greatly reduced (6.0-28.4%) at 0.5, 2.0, and 10.0 C. The mortality of embryos was greatest during the early stages of development. Abnormally developed fry were most frequent (85.9% of the hatch) at 10.0 C, and least frequent (2.8%) at 4.0 C. Mean lengths of fry at hatching were shorter at 7.8 and 10.0 C (12.4 and 8.8 mm, respectively) than at lower temperatures (13.1 to 13.5 mm). The optimum temperature range for incubation of lake whitefish eggs was 3.2 to 8.1 C. Equations were derived for predicting development time to 20 successive stages, and to hatching, at constant incubation temperatures and at fluctuating daily mean water temperatures.
NASA Astrophysics Data System (ADS)
Shebl, Magdy; Adly, Omima M. I.; Abdelrhman, Ebtesam M.; El-Shetary, B. A.
2017-10-01
A new Schiff base ligand was synthesized by the reaction of 4-acetyl-5,6-diphenyl-3(2H)-pyridazinone with ethylenediamine. A series of binary copper(II) Schiff base complexes have been synthesized by using various copper(II) salts; AcO-, NO3-, ClO4-, Cl- and Br-. Ternary complexes were synthesized by using auxiliary ligands (L‧) [N,O-donor; 8-hydroxyquinoline and glycine or N,N-donor; 1,10-phenanthroline, bipyridyl and 2-aminopyridine]. The structures of the Schiff base and its complexes were characterized by elemental and thermal analyses, IR, electronic, mass, 1H NMR and ESR spectra in addition to conductivity and magnetic susceptibility measurements. The obtained complexes include neutral binuclear complexes as well as neutral and cationic mononuclear complexes according to the anion used and the experimental conditions. The ESR spin Hamiltonian parameters of some complexes were calculated and discussed. The metal complexes exhibited octahedral and square planar geometrical arrangements depending on the nature of the anion. Kinetic parameters (Ea, A, ΔH, ΔS and ΔG) of the thermal decomposition stages were evaluated using Coats-Redfern equations. The antimicrobial activity of the Schiff base and its complexes was screened against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), Gram-negative bacteria (Salmonella typhimurium and Escherichia coli), yeast (Candida albicans) and fungus (Aspergillus fumigatus). The antitumor activity of the Schiff base and some of its Cu(II) complexes was investigated against HepG-2 cell line.
Stability of iron-bearing carbonates in the deep Earth’s interior
Cerantola, Valerio; Bykova, Elena; Kupenko, Ilya; ...
2017-07-19
The presence of carbonates in inclusions in diamonds coming from depths exceeding 670 km are obvious evidence that carbonates exist in the Earth’s lower mantle. However, their range of stability, crystal structures and the thermodynamic conditions of the decarbonation processes remain poorly constrained. We investigate the behaviour of pure iron carbonate at pressures over 100 GPa and temperatures over 2,500 K using single-crystal X-ray diffraction and Mossbauer spectroscopy in laser-heated diamond anvil cells. On heating to temperatures of the Earth’s geotherm at pressures to B 50 GPa FeCO 3 partially dissociates to form various iron oxides. Furthermore, at higher pressures FeCO 3 forms two new structures— tetrairon(III) orthocarbonate Femore » $$3+\\atop{4}$$C 3O 12 and diiron(II) diiron(III) tetracarbonate Fe$$2+\\atop{2}$$ Fe$$3+\\atop{2}$$C 4 O 13, both phases containing CO 4 tetrahedra. Fe 4 C 4 O 13 is stable at conditions along the entire geotherm to depths of at least 2,500 km, thus demonstrating that self-oxidation-reduction reactions can preserve carbonates in the Earth’s lower mantle.« less
Hernández-Carranza, Paola; Ruiz-López, Irving Israel; Pacheco-Aguirre, Francisco Manuel; Guerrero-Beltrán, José Ángel; Ávila-Sosa, Raúl; Ochoa-Velasco, Carlos Enrique
2016-09-01
The aim of this research was to evaluate the effect of ultraviolet-C light on physicochemical, bioactive, microbial, and sensory characteristics of carrot beverages. Beverages were formulated with different concentrations of carrot juice (60, 80, and 100% [v/v]) and treated with ultraviolet-C light at different flow rates (0, 0.5, 3.9, and 7.9 mL s(-1)) and times (5, 10, 15, 20, and 30 min), equivalent to ultraviolet-C dosages of 13.2, 26.4, 39.6, 52.8, and 79.2 J cm(-2) Total soluble solids, pH, and titratable acidity were not affected by the ultraviolet-C light treatment. Ultraviolet-C light significantly affected (p < 0.05) color parameters of pure juice; however, at low concentration of juice, total color change was slightly affected (ΔE = 2.0 ± 0.7). Phenolic compounds (4.1 ± 0.1, 5.2 ± 0.2, and 8.6 ± 0.3 mg of GAE 100 mL(-1) of beverage with 60, 80, and 100% of juice, respectively) and antioxidant capacity (6.1 ± 0.4, 8.5 ± 0.4, and 9.4 ± 0.3 mg of Trolox 100 mL(-1) of beverage with 60, 80, and 100% of juice, respectively) of carrot beverages were not affected by ultraviolet-C light treatment. Microbial kinetics showed that mesophiles were mostly reduced at high flow rates in carrot beverages with 60% of juice. Maximum logarithmic reductions for mesophiles and total coliforms were 3.2 ± 0.1 and 2.6 ± 0.1, respectively, after 30 min of ultraviolet-C light processing. Beverages were well accepted (6-7) by judges who did not perceive the difference between untreated and Ultraviolet-C light treated beverages. © The Author(s) 2016.
NASA Astrophysics Data System (ADS)
Koga, Yoshikata; Westh, Peter; Yoshida, Koh; Inaba, Akira; Nakazawa, Yasuhiro
2014-09-01
Using the literature raw data of the speed of sound and the specific volume, the isothermal compressibility, κT, a second derivative thermodynamic quantity of G, was evaluated for liquid H2O in the pressure range up to 350 MPa and the temperature to 50 °C. We then obtained its pressure derivative, dκT/dp, a third derivative numerically without using a fitting function to the κT data. On taking yet another p-derivative at a fixed T graphically without resorting to any fitting function, the resulting d2κT/dp2, a fourth derivative, showed a weak but clear step anomaly, with the onset of the step named point X and its end point Y. In analogy with another third and fourth derivative pair in binary aqueous solutions of glycerol, dαp/dxGly and d2αp/dxGly2, at 0.1 MPa (αp is the thermal expansivity and xGly the mole fraction of solute glycerol) in our recent publication [J. Solution Chem. 43, 663-674 (2014); DOI:10.1007/s10953-013-0122-7], we argue that there is a gradual crossover in the molecular organization of pure H2O from a low to a high p-regions starting at point X and ending at Y at a fixed T. The crossover takes place gradually spanning for about 100 MPa at a fixed temperature. The extrapolated temperature to zero p seems to be about 70 - 80 °C for points X and 90 - 110 °C for Y. Furthermore, the mid-points of X and Y seem to extrapolate to the triple point of liquid, ice Ih and ice III. Recalling that the zero xGly extrapolation of point X and Y for binary aqueous glycerol at 0.1 MPa gives about the same T values respectively, we suggest that at zero pressure the region below about 70 °C the hydrogen bond network is bond-percolated, while above about 90 °C there is no hydrogen bond network. Implication of these findings is discussed.
Gonzalo-Lumbreras, R; Izquierdo-Hornillos, R
2000-05-26
An HPLC separation of a complex mixture containing 13 urinary anabolics and corticoids, and boldenone and bolasterone (synthetic anabolics) has been carried out. The applied optimization method involved the use of binary, ternary and quaternary mobile phases containing acetonitrile, methanol or tetrahydrofuran as organic modifiers. The effect of different reversed-phase packings and temperature on the separation was studied. The optimum separation was achieved by using a water-acetonitrile (60:40, v/v) mobile phase in reversed-phase HPLC at 30 degrees C, allowing the separation of all the analytes in about 24 min. Calibration graphs were obtained using bolasterone or methyltestosterone as internal standards. Detection limits were in the range 0.012-0.107 microg ml(-1). The optimized separation was applied to the analysis, after liquid-liquid extraction, of human urine samples spiked with steroids.
Van Guyse, Joachim F R; de la Rosa, Victor R; Hoogenboom, Richard
2018-02-21
Buckminster fullerene (C 60 )'s main hurdle to enter the field of biomedicine is its low bioavailability, which results from its extremely low water solubility. A well-known approach to increase the water solubility of C 60 is by complexation with γ-cyclodextrins. However, the formed complexes are not stable in time as they rapidly aggregate and eventually precipitate due to attractive intermolecular forces, a common problem in inclusion complexes of cyclodextrins. In this study we attempt to overcome the attractive intermolecular forces between the complexes by designing custom γ-cyclodextrin (γCD)-based supramolecular hosts for C 60 that inhibit the aggregation found in native γCD-C 60 complexes. The approach entails the introduction of either repulsive electrostatic forces or increased steric hindrance to prevent aggregation, thus enhancing the biomedical application potential of C 60 . These modifications have led to new sub-100 nm nanostructures that show long-term stability in solution. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
1983-11-01
Isolation FIT Fault Isolation Test FMC Fully Mission Capable FMEA Failure Modes and Effects Analysis FMECA Failure Modes, Effects and Criticality...8217 ..* ,/- " , " A ’’"""¢ 9 % ’ k " . " ~ .[:, .- v," . , , .’ % , o4,o 100 92 88 0 80 76 PERCENT -- __ OF F-16 60 FLIGHTS WITHOUT NATO NATO RADAR HILL BASE BASE...to manage a growth program adequately. 822/1-13 IV-13 %. - 70 60 F-ill 50 F-1 5 40- CL. C.c 30 - IF-1 S20 ICIC p 10 I~* -. -. - - -____ F-5E -4 -3 -2
HESS J1844-030: A New Gamma-Ray Binary?
NASA Astrophysics Data System (ADS)
McCall, Hannah; Errando, Manel
2018-01-01
Gamma-ray binaries are comprised of a massive, main-sequence star orbiting a neutron star or black hole that generates bright gamma-ray emission. Only six of these systems have been discovered. Here we report on a candidate stellar-binary system associated with the unidentified gamma-ray source HESS J1844-030, whose detection was revealed in the H.E.S.S. galactic plane survey. Analysis of 60 ks of archival Chandra data and over 100 ks of XMM-Newton data reveal a spatially associated X-ray counterpart to this TeV-emitting source (E>1012 eV), CXO J1845-031. The X-ray spectra derived from these exposures yields column density absorption in the range nH = (0.4 - 0.7) x 1022 cm-2, which is below the total galactic value for that part of the sky, indicating that the source is galactic. The flux from CXO J1845-031 increases with a factor of up to 2.5 in a 60 day timescale, providing solid evidence for flux variability at a confidence level exceeding 7 standard deviations. The point-like nature of the source, the flux variability of the nearby X-ray counterpart, and the low column density absorption are all indicative of a binary system. Once confirmed, HESS J1844-030 would represent only the seventh known gamma-ray binary, providing valuable data to advance our understanding of the physics of pulsars and stellar winds and testing high-energy astrophysical processes at timescales not present in other classes of objects.
Searching Planets Around Some Selected Eclipsing Close Binary Stars Systems
NASA Astrophysics Data System (ADS)
Nasiroglu, Ilham; Slowikowska, Agnieszka; Krzeszowski, Krzysztof; Zejmo, M. Michal; Er, Hüseyin; Goździewski, Krzysztof; Zola, Stanislaw; Koziel-Wierzbowska, Dorota; Debski, Bartholomew; Ogloza, Waldemar; Drozdz, Marek
2016-07-01
We present updated O-C diagrams of selected short period eclipsing binaries observed since 2009 with the T100 Telescope at the TUBITAK National Observatory (Antalya, Turkey), the T60 Telescope at the Adiyaman University Observatory (Adiyaman, Turkey), the 60cm at the Mt. Suhora Observatory of the Pedagogical University (Poland) and the 50cm Cassegrain telescope at the Fort Skala Astronomical Observatory of the Jagiellonian University in Krakow, Poland. All four telescopes are equipped with sensitive, back-illuminated CCD cameras and sets of wide band filters. One of the targets in our sample is a post-common envelope eclipsing binary NSVS 14256825. We collected more than 50 new eclipses for this system that together with the literature data gives more than 120 eclipse timings over the time span of 8.5 years. The obtained O-C diagram shows quasi-periodic variations that can be well explained by the existence of the third body on Jupiter-like orbit. We also present new results indicating a possible light time travel effect inferred from the O-C diagrams of two other binary systems: HU Aqr and V470 Cam.
More surprises from the violent gamma-ray binary LS 2883 /B1259-63.
NASA Astrophysics Data System (ADS)
Kargaltsev, Oleg; Hare, Jeremy; Pavlov, George G.
2018-01-01
We report the results of a Chandra X-ray Observatory (CXO) monitoring campaign of the high-mass gamma-ray binary LS 2883, which hosts the young pulsar B1259-63. The monitoring now covers two binary cycles (6.8 years) and allows us to conclude that ejections of high-velocity X-ray emitting material are common for this binary. In the first cycle we observed an extended feature which detached and moved away from the binary. The observed changes in position were consistent with a steady motion with v=(0.07+/-0.01)c and a slight hint of acceleration. Tracing the motion back in time suggested that the X-ray emitting matter was ejected close to periastron passage. In the last orbital cycle, accelerated motion (reaching (0.13+/-0.02)c) is strongly preferred over a steady motion (the latter would imply that the ejected material was launched ~400 days after the periastron passage). The moving feature is also more luminous, compared to the previous binary cycle, larger in its apparent extent, and exhibits a puzzling morphology. We will show the CXO movies from both binary cycles and discuss physical interpretation of the resolved outflow dynamics in this remarkable system, which provides unique insight into the properties of the pulsar and stellar winds and their interaction.
Boons, Kathleen; Noriega, Estefanía; Verherstraeten, Niels; David, Charlotte C; Hofkens, Johan; Van Impe, Jan F
2015-04-16
As most food systems are (semi-)solid, the effect of food structure on bacterial growth has been widely acknowledged. However, studies on the growth dynamics of yeasts have neglected the effect of food structure. In this paper, the growth dynamics of the spoilage yeast Saccharomyces cerevisiae was investigated at 23.5 °C in broth, singular, homogeneous biopolymer systems and binary biopolymer systems with a heterogeneous microstructure. The biopolymers gelatin and dextran were used to introduce the different levels of structure. The metabolizing ability of gelatin and dextran by S. cerevisiae was examined. To study microbial behavior in the binary systems at the micro level, mixtures were imaged with confocal laser scanning microscopy (CLSM). Growth dynamics and microscopic images of S. cerevisiae were compared with those obtained for Escherichia coli in the same model system (Boons et al., 2014). Different phase-separated, heterogeneous microstructures were obtained by changing the amount of added gelatin and dextran. Regardless of the microstructure, S. cerevisiae was preferentially located in the dextran phase. Metabolizing ability-tests indicated that gelatin could be consumed by S. cerevisiae but in the presence of glucose, no change in gelatin concentration was observed. No indication of dextran metabolizing ability was observed. When supplementing broth with gelatin or dextran alone, an enhanced growth rate and maximum cell density were observed. This enhancement was further increased by adding a second biopolymer, introducing a heterogeneous microstructure and hence increasing the medium structure complexity. The results obtained indicate that food structure complexity plays a significant role in the growth dynamics of S. cerevisiae, an important food spoiler. Copyright © 2014. Published by Elsevier B.V.
Chiou, C.T.; Kile, D.E.
1998-01-01
A series of single-solute and binary-solute sorption data have been obtained on representative samples of polar compounds (substituted ureas and phenolic compounds) and of nonpolar compounds (e.g., EDB and TCE) on a peat soil and a mineral (Woodburn) soil; the data extend to low relative solute concentrations (C(e)/S(w)). At relatively low C(e)/S(w), both the nonpolar and the polar solutes exhibit nonlinear sorption. The sorption nonlinearity approaches apparent saturation at about C(e)/S(w) = 0.010-0.015 for the nonpolar solutes and at about C(e)/S(w) = 0.10-0.13 for the polar solutes; above these C(e)/S(w) regions, the isotherms are practically linear. The nonlinear sorption capacities are greater for polar solutes than for nonpolar solutes and the peat soil shows a greater effect than the Woodburn soil. The small nonlinear sorption capacity for a nonpolar solute is suppressed indiscriminately by either a nonpolar or a polar cosolute at relatively low C(e)/S(w) of the cosolute. By contrast, the abilities of different cosolutes to suppress the nonlinear capacity of a nominal polar solute differ drastically. For polar solutes, a nonpolar cosolute exhibits a limited suppression even at high cosolute C(e)/S(w); effective suppression occurs when the cosolute is relatively polar and at various C(e)/S(w). These differences suggest that more than a single mechanism is required to account for the nonlinear sorption of both nonpolar and polar compounds at low C(e)/S(w). Mechanistic processes consistent with these observations and with soil surface areas are discussed along with other suggested models. Some important consequences of the nonlinear competitive sorption to the behavior of contaminants in natural systems are discussed.A number of conceptual models was postulated to account for the nonlinear solute sorption on soils of significant soil organic matter. A series of single-solute and binary-route sorption data was obtained representing samples of polar compounds of substituted ureas and phenolic compounds, and of nonpolar compounds of EDB and trichloroethylene on a peat soil and a mineral on a Woodburn soil. The nonlinear sorption capacities are greater for polar solutes than for nonpolar solutes and the peat soil shows a greater effect than the Woodburn soil.
Enhanced Electro-Optic Phase Shifts in Suspended Waveguides
2010-01-18
section,” J. Lightwave. Technol. (16), 1851–1853 (1998). 9. T . Ikegami , “Reflectivity of mode at facet and oscillation mode in double-heterostructure...Enhanced Electro-Optic Phase Shifts in Suspended Waveguides T . H. Stievater,1 D. Park,1 W. S. Rabinovich,1 M. W. Pruessner,1, S. Kanakaraju,2 C. J. K... T . H. Stievater, W. S. Rabinovich, P. G. Goetz, R. Mahon, and S. C. Binari, “A Surface-Normal Coupled- Quantum-Well Modulator at 1.55 Microns,” IEEE
Burton, B. P.; Rawn, C. J.; Roth, R. S.; Hwang, N. M.
1993-01-01
New data are presented on the phase equilibria and crystal chemistry of the binary systems CaO-Bi2O3 and CaO-CuO and the ternary CaO-Bi2O3-CuO. Symmetry data and unit cell dimensions based on single crystal and powder x-ray diffraction measurements are reported for several of the binary CaO-Bi2O3 phases, including corrected compositions for Ca4Bi6O13 and Ca2Bi2O5. The ternary system contains no new ternary phases which can be formed in air at ~700–900 °C. PMID:28053484
NASA Astrophysics Data System (ADS)
Ebrahimpoor, Sonia; Khoshnood, Razieh Sanavi; Beyramabadi, S. Ali
2016-12-01
Complexation of the Cd2+ ion with N, N'-dipyridoxylidene(1,4-butanediamine) Schiff base was studied in pure solvents including acetonitrile (AN), ethanol (EtOH), methanol (MeOH), tetrahydrofuran (THF), dimethylformamide (DMF), water (H2O), and various binary solvent mixtures of acetonitrile-ethanol (AN-EtOH), acetonitrile-methanol (AN-MeOH), acetonitrile-tetrahydrofuran (AN-THF), acetonitrile-dimethylformamide (AN-DMF), and acetonitrile-water (AN-H2O) systems at different temperatures using the conductometric method. The conductance data show that the stoichiometry of complex is 1: 1 [ML] in all solvent systems. A non-linear behavior was observed for changes of log K f of [Cd( N, N'-dipyridoxylidene(1,4-butanediamine)] complex versus the composition of the binary mixed solvents, which was explained in terms of solvent-solvent interactions. The results show that the thermodynamics of complexation reaction is affected by the nature and composition of the mixed solvents.
Jones, Leigh F; Rajaraman, Gopalan; Brockman, Jonathon; Murugesu, Muralee; Sanudo, E Carolina; Raftery, Jim; Teat, Simon J; Wernsdorfer, Wolfgang; Christou, George; Brechin, Euan K; Collison, David
2004-10-11
The syntheses, structures and magnetic properties of three new MnIII clusters, [Mn26O17(OH)8(OMe)4F10(bta)22(MeOH)14(H2O)2] (1), [Mn(0O6(OH)2(bta)8(py)8F8] (2) and [NHEt3]2[Mn3O(bta)6F3] (3), are reported (bta=anion of benzotriazole), thereby demonstrating the utility of MnF3 as a new synthon in Mn cluster chemistry. The "melt" reaction (100 degrees C) between MnF(3) and benzotriazole (btaH, C6H5N3) under an inert atmosphere, followed by dissolution in MeOH produces the cluster [Mn26O17(OH)8(OMe)4F10(bta)22(MeOH)14(H2O)2] (1) after two weeks. Complex 1 crystallizes in the triclinic space group P1, and consists of a complicated array of metal tetrahedra linked by mu3-O2- ions, mu3- and mu2-OH- ions, mu2-MeO- ions and mu2-bta- ligands. The "simpler" reaction between MnF3 and btaH in boiling MeOH (50 degrees C) also produces complex 1. If this reaction is repeated in the presence of pyridine, the decametallic complex [Mn10O6(OH)2(bta)8(py)8F8] (2) is produced. Complex 2 crystallizes in the triclinic space group P1 and consists of a "supertetrahedral" [Mn(III)10] core bridged by six mu3-O2- ions, two mu3-OH- ions, four mu2-F- ions and eight mu2-bta- ions. The replacement of pyridine by triethylamine in the same reaction scheme produces the trimetallic species [NHEt3]2[Mn3O(bta)6F3] (3). Complex 3 crystallises in the monoclinic space group P2(1)/c and has a structure analogous to that of the basic metal carboxylates of general formula [M3O(RCO2)6L3]0/+, which consists of an oxo-centred metal triangle with mu2-bta- ligands bridging each edge of the triangle and the fluoride ions acting as the terminal ligands. DC magnetic susceptibility measurements in the 300-1.8 K and 0.1-7 T ranges were investigated for all three complexes. For each, the value of chi(M)T decreases with decreasing temperatures; this indicates the presence of dominant antiferromagnetic exchange interactions in 1-3. For complex 1, the low-temperature value of chi(M)T is 10 cm(3) K mol(-1) and fitting of the magnetisation data gives S=4, g=2.0 and D=-0.90 cm(-1). For complex 2, the value of chi(M)T falls to a value of approximately 5.0 cm(3) K mol(-1) at 1.8 K, which is consistent with a small spin ground state. For the triangular complex 3, the best fit to the experimental chi(M)T versus T data was obtained for the following parameters: Ja = -5.01 cm(-1), Jb = +9.16 cm(-1) and g=2.00, resulting in an S=2 spin ground state. DFT calculations on 3, however, suggest an S=1 or S=0 ground state with J(a)=-2.95 cm(-1) and J(b)=-2.12 cm(-1). AC susceptibility measurements performed on 1 in the 1.8-4.00 K range show the presence of out-of-phase AC susceptibility signals, but no peaks. Low-temperature single-crystal studies performed on 1 on an array of micro-SQUIDS show the time- and temperature-dependent hysteresis loops indicative of single-molecule magnetism behaviour.
MAXI/GSC detection of a new outburst from SAX J1810.8-2609
NASA Astrophysics Data System (ADS)
Negoro, H.; Mihara, T.; Nakahira, S.; Yatabe, F.; Takao, Y.; Matsuoka, M.; Kawai, N.; Sugizaki, M.; Tachibana, Y.; Morita, K.; Sakamoto, T.; Serino, M.; Sugita, S.; Kawakubo, Y.; Hashimoto, T.; Yoshida, A.; Nakajima, M.; Sakamaki, A.; Maruyama, W.; Ueno, S.; Tomida, H.; Ishikawa, M.; Sugawara, Y.; Isobe, N.; Shimomukai, R.; Ueda, Y.; Tanimoto, A.; Morita, T.; Yamada, S.; Tsuboi, Y.; Iwakiri, W.; Sasaki, R.; Kawai, H.; Sato, T.; Tsunemi, H.; Yoneyama, T.; Yamauchi, M.; Hidaka, K.; Iwahori, S.; Kawamuro, T.; Yamaoka, K.; Shidatsu, M.
2018-05-01
We report a new X-ray outburst from the low-mass X-ray binary SAX J1810.8-2609 (aka V4722 Sgr; Ubertini et al. 1998, IAUC 6838) observed with MAXI/GSC. The enhancement was recognized from 2018 April 23 (MJD 58231), and X-ray count rates in the 2-4 keV and 4-10 keV bands peaked on April 26 at 0.085 +/- 0.008 c/s/cm2 ( 80 mCrab) and 0.096+/-0.008 c/s/cm2 ( 82 mCrab), respectively.
Proceedings of Damping , Held in San Diego, California on 13 - 15 February 1991. Volume 2
1991-08-01
Efficiency CBC* Dr. L. H. Sperling , J. J. Fay, and Dr. D. A. Thomas The Thermorheologically Complex Material CBD* Lt. Col. Ronald L. Bagley SESSION CC...Andrew S. Bicos. and J. S. Fechter The Need for Passive Damping in Feedback Controlled Flexible Struc- GBB tures Dr. Andreas von Flotow and D. W. Vos...Vibration Research, Southampton, England (R.C. Drew) Lehigh University, Bethlehem, Pennsylvania (L. Sperling ) MrS Corporation, Minneapolis, Minnesota