History of the AFRL/USC DARPA Program on Polynitrogen Chemistry. Volume 2
2004-10-01
published by Pyykkoe and Runeberg in 1991 as part of a systematic study of the isoelectronic dicyanamide series, but little emphasis was given to N5+ as...2003, 244, 93. [3] K. O. Christe, R. D. Wilson, W. W. Wilson, R. Bau, S. Sukumar, D. A. Dixon, J. Am. Chem. Soc. 1991 , 113, 1991 . [4] P...Pyykkoe, N. Runeberg, J. Mol. Struct. (Theochem.) 1991 , 234, 279. [5] R. Rawls, Chem. & Eng. News, Jan. 25 issue, 1999, pg. 7. [6] P. Zurer, Chem
Structure, Kinetics, and Thermodynamics of the Aqueous Uranyl(VI) Cation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kerisit, Sebastien N.; Liu, Chongxuan
2013-08-20
Molecular simulation techniques are employed to gain insights into the structural, kinetic, and thermodynamic properties of the uranyl(VI) cation (UO22+) in aqueous solution. The simulations make use of an atomistic potential model (force field) derived in this work and based on the model of Guilbaud and Wipff (Guilbaud, P.; Wipff, G. J. Mol. Struct. (THEOCHEM) 1996, 366, 55-63). Reactive flux and thermodynamic integration calculations show that the derived potential model yields predictions for the water exchange rate and free energy of hydration, respectively, that are in agreement with experimental data. The water binding energies, hydration shell structure, and self-diffusion coefficientmore » are also calculated and discussed. Finally, a combination of metadynamics and transition path sampling simulations is employed to probe the mechanisms of water exchange reactions in the first hydration shell of the uranyl ion. These atomistic simulations indicate, based on two-dimensional free energy surfaces, that water exchanges follow an associative interchange mechanism. The nature and structure of the water exchange transition states are also determined. The improved potential model is expected to lead to more accurate predictions of uranyl adsorption energies at mineral surfaces using potential-based molecular dynamics simulations.« less
Durig, Douglas T; Durig, M S; Durig, James R
2005-05-01
The infrared and Raman spectra of methyl, silyl, and germyl azide (XN3 where X=CH3, SiH3 and GeH3) have been predicted from ab initio calculations with full electron correlation by second order perturbation theory (MP2) and hybrid density function theory (DFT) by the B3LYP method with a variety of basis sets. These predicted data are compared to previously reported experimental data and complete vibrational assignments are provided for all three molecules. It is shown that several of the assignments recently proposed [J. Mol. Struct. (Theochem.) 434 (1998) 1] for methyl azide are not correct. Structural parameters for CH3N3 and GeH3N3 have been obtained by combining the previously reported microwave rotational constants with the ab initio MP2/6-311+G(d,p) predicted values. These "adjusted r0" parameters have very small uncertainties of +/-0.003 A for the XH distances and a maximum of +/-0.005 A for the heavy atom distances and +/-0.5 degrees for the angles. The predicted distance for the terminal NN bond which is nearly a triple bond is much better predicted by the B3LYP calculations, whereas the fundamental frequencies are better predicted by the scaled ab initio calculations. The results are discussed and compared to those obtained for some similar molecules.
de la Lande, A.; Maddaluno, J.; Parisel, O.; Darden, T. A.; Piquemal, J-P
2010-01-01
Following our previous study (Piquemal et al., New J. Chem., 2003, 27, 909), we present here a DFT study of the inhibition of the Tyrosinase enzyme. Broken-symmetry DFT computations are supplemented with Spin-Flip TD-DFT calculations, which, for the first time, are applied to such a dicopper enzyme. The chosen biomimetic model encompasses a dioxygen molecule, two Cu(II) cations, and six imidazole rings. The docking energy of a natural substrate, namely phenolate, together with those of several inhibitor and non-inhibitor compounds, are reported and show the ability of the model to rank the most potent inhibitors in agreement with experimental data. With respect to broken-symmetry calculations, the Spin-Flip TD-DFT approach reinforces the possibility for theory to point out potent inhibitors: the need for the deprotonation of the substrates, natural or inhibitors, is now clearly established. Moreover, Electron Localization Function (ELF) topological analysis computations are used to deeply track the particular electronic distribution of the Cu-O-Cu three-center bonds involved in the enzymatic Cu2O2 metallic core (Piquemal and Pilmé, J. Mol. Struct.: Theochem, 2006, 77, 764). It is shown that such bonds exhibit very resilient out-of-plane density expansions that play a key role in docking interactions: their 3D-orientation could be the topological electronic signature of oxygen activation within such systems. PMID:20396590
NASA Astrophysics Data System (ADS)
Barakat, Assem; Al-Majid, Abdullah Mohammed; Soliman, Saied M.; Islam, Mohammad Shahidul; Ghawas, Hussain Mansur; Yousuf, Sammer; Choudhary, M. Iqbal; Wadood, Abdul
2017-09-01
;The correct CCDC reference for the compound 3k is 1546475 instead of 1024287 as mentioned in the text on page 625. The authors regret this error and would like to apologize for any inconvenience caused to anyone.;
NASA Astrophysics Data System (ADS)
Vovna, Vitaliy I.; Korochentsev, Vladimir V.; Komissarov, Alexander A.; L'vov, Igor B.; Myshakina, Nataliya S.
2016-01-01
The authors regret to inform that it was given erroneous spelling of Vitaliy I. Vovna author name in the published version of the article. It was written "Vitaliy V. Vovna" instead of "Vitaliy I. Vovna".
NASA Astrophysics Data System (ADS)
Reinscheid, F.; Reinscheid, U. M.
2016-04-01
The authors regret to inform that a typographical error occurred in the published version of the article. In the last sentence of the abstract and of the conclusion the correct expression with the specific optical rotation should read "-10 < [α] < +10". We would like to apologize for the inconvenience caused.
2013-01-01
Koura, S. Kohara , K. Takeuchi, S. Takahashi, L. A. Curtiss, M. Grimsditch and M.-L. Saboungi, J. Mol. Struct., 1996, 382, 163–169. 49 L.-J. Chen, X...Cheng, C.-J. Lin and C.-M. Huang, Electrochim. Acta, 2002, 47, 1475–1480. 50 S. Kohara , N. Koura, Y. Idemoto, S. Takahashi, M.-L. Saboungi and L. A
NASA Astrophysics Data System (ADS)
Mani, Devendra; Pal, Nitish; Kaufmann, Matin; Schwaab, Gerhard; Havenith, Martina
2016-06-01
Propargyl alcohol (hereafter abbreviated as PA) is a molecule of astrophysical interest and has been probed extensively using microwave spectroscopy.1,2 It is a multifunctional molecule and offers multiple sites for hydrogen bonding interactions. Therefore, it has also attracted the attention of groups interested in weak intermolecular interactions. Recently, the Ar…PA complex3 and PA-dimer4 have been studied using microwave spectroscopy. More recently, there have been matrix-isolation infrared spectroscopic studies on PA-water5 and PA-acetylene6 complexes. In the present work, clusters of PA and water were formed in the helium nanodroplets and probed using a combination of infrared spectroscopy and mass spectrometry. Using ab-initio quantum mechanical calculations, PA-water clusters were optimised and five minimum structures were found on the potential energy hypersurface, which were used as a guidance to the experiments. We used D2O for the experiments since our laser sources at Bochum do not cover the IR spectral region of H2O. IR spectra of PA-D2O complex were recorded in the region of symmetric and antisymmetric stretches of the bound D2O. Multiple signals were found in these regions which were dependent on the concentration of PA as well as D2O. Using pickup curves most of these signals could be assigned to 1:1 PA:D2O clusters. The ab-initio calculations helped in a definitive assignment of the spectra to the different conformers of PA-D2O complex. The details will be presented in the talk. References: 1. E. Hirota, J. Mol. Spec. 26, 335 (1968). 2. J.C. Pearson and B.J. Drouin, J. Mol. Spectrosc. 234, 149 (2005). 3. D. Mani and E. Arunan, ChemPhysChem 14, 754 (2013). 4. D. Mani and E. Arunan, J. Chem. Phys. 141, 164311 (2014). 5. J. Saini, K.S. Vishwanathan, J. Mol. Struct. 1118, 147 (2016). 6. K. Sundararajan et al., J. Mol. Struct. 1121, 26 (2016).
Annual Report on Electronics Research at The University of Texas at Austin.
1982-05-15
Professor, Physics, 471-5747 L. Frommhold, Professor, Physics, 471-5100 J. Keto , Associate Professor, Physics, 471-4151 H.J. Kimble, Assistant Professor...Scattering Cross Section of Argon Diatom," Canad. J. Physics, 59, 1418 (1981). *Michael H. Proffitt, J.W. Keto and Lothar Frommhold, "Col- lision Induced...Elec- tron Diffraction Study of the Structure of Anthraquinone and Anthracene," J. Mol. Struct. 77, 127-138 (1981). J.W. Keto , T.D. Raymond and Chien-Yu
NASA Astrophysics Data System (ADS)
Sıdır, Yadigar Gülseven; Sıdır, İsa; Demiray, Ferhat
2017-08-01
The authors regret to inform that three references in the article titled ;Dipole moment and solvatochromism of benzoic acid liquid crystals: Tuning the dipole moment and molecular orbital energies by substituted Au under external electric field; are not given in the manuscript. This is purely an oversight mistake. The references are as shown in this correction. The authors would like to apologize for any inconvenience caused.
2012-11-05
organization of measles virus fusion complexes. J Virol 83: 10480–10493. 24. Bishop KA, Hickey AC, Khetawat D, Patch JR, Bossart KN, et al. (2008...its receptor, sialyllactose. Structure 13: 803–815. 38. Colf LA, Juo ZS, Garcia KC (2007) Structure of the measles virus hemagglutinin. Nat Struct Mol...Biol 14: 1227–1228. 39. Hashiguchi T, Kajikawa M, Maita N, Takeda M, Kuroki K, et al. (2007) Crystal structure of measles virus hemagglutinin provides
NASA Astrophysics Data System (ADS)
Kim, Sunghoon; Kim, Dongil; Lee, Ha-Jin; Lee, Hyosun
2015-05-01
The authors regret to inform that 4,4‧-bis-(N,N-di(1H-pyrazolyl-1-methyl)phenyl)methane (L2) and its binuclear 4,4‧-bis-(N,N-di-(1H-pyrazolyl-1-methyl)phenyl)methane(dichloro)Zn(II) complex, namely, [L2Zn2Cl4] in the paper were published as the thesis for the degree of master in the Department of Chemistry at Kyungpook National University in 2003.
Redetermination of 2-methyl-4-nitropyridine N-oxide
Peukert, Max; Seichter, Wilhelm; Weber, Edwin
2014-01-01
An improved crystal structure of the title compound, C6H6N2O3, is reported. The structure, previously solved [Li et al. (1987 ▶). Jiegou Huaxue (Chin. J. Struct. Chem.), 6, 20–24] in the orthorhombic space group Pca21 and refined to R = 0.067, has been solved in the orthorhombic space group Pbcm with data of enhanced quality, giving an improved structure (R = 0.0485). The molecule adopts a planar conformation with all atoms lying on a mirror plane. The crystal structure is composed of molecular sheets extending parallel to the ab plane and connected via C—H⋯O contacts involving ring H atoms and O atoms of the N-oxide and nitro groups, while van der Waals forces consolidate the stacking of the layers. PMID:24826136
Simulaid: a simulation facilitator and analysis program.
Mezei, Mihaly
2010-11-15
Simulaid performs a large number of simulation-related tasks: interconversion and modification of structure and trajectory files, optimization of orientation, and a large variety of analysis functions. The program can handle structures in PDB (Berman et al., Nucleic Acids Res 2000, 28, 235), Charmm (Brooks et al., J Comput Chem 4, 187) CRD, Amber (Case et al.), Macromodel (Mohamadi et al., J Comput Chem 1990, 11, 440), Gromos/Gromacs (Hess et al.), InsightII (InsightII. Accelrys Inc.: San Diego, 2005), Grasp (Nicholls et al., Proteins: Struct Funct Genet 1991, 11, 281) .crg, Tripos (Tripos International, S. H. R., St. Louis, MO) .mol2 (input only), and in the MMC (Mezei, M.; MMC: Monte Carlo program for molecular assemblies. Available at: http://inka.mssm.edu/~mezei/mmc) formats; and trajectories in the formats of Charmm, Amber, Macromodel, and MMC. Analysis features include (but are not limited to): (1) simple distance calculations and hydrogen-bond analysis, (2) calculation of 2-D RMSD maps (produced both as text file with the data and as a color-coded matrix) and cross RMSD maps between trajectories, (3) clustering based on RMSD maps, (4) analysis of torsion angles, Ramachandran (Ramachandran and Sasiskharan, Adv Protein Chem 1968, 23, 283) angles, proline kink (Visiers et al., Protein Eng 2000, 13, 603) angles, pseudorotational (Altona and Sundaralingam, J Am Chem Soc 1972, 94, 8205; Cremer and Pople, J Am Chem Soc 1975, 97, 1354) angles, and (5) analysis based on circular variance (Mezei, J Mol Graphics Model 2003, 21, 463). Torsion angle evolutions are presented in dial plots (Ravishanker et al., J Biomol Struct Dyn 1989, 6, 669). Several of these features are unique to Simulaid. 2010 Wiley Periodicals, Inc.
Cross-language Babel structs—making scientific interfaces more efficient
NASA Astrophysics Data System (ADS)
Prantl, Adrian; Ebner, Dietmar; Epperly, Thomas G. W.
2013-01-01
Babel is an open-source language interoperability framework tailored to the needs of high-performance scientific computing. As an integral element of the Common Component Architecture, it is employed in a wide range of scientific applications where it is used to connect components written in different programming languages. In this paper we describe how we extended Babel to support interoperable tuple data types (structs). Structs are a common idiom in (mono-lingual) scientific application programming interfaces (APIs); they are an efficient way to pass tuples of nonuniform data between functions, and are supported natively by most programming languages. Using our extended version of Babel, developers of scientific codes can now pass structs as arguments between functions implemented in any of the supported languages. In C, C++, Fortran 2003/2008 and Chapel, structs can be passed without the overhead of data marshaling or copying, providing language interoperability at minimal cost. Other supported languages are Fortran 77, Fortran 90/95, Java and Python. We will show how we designed a struct implementation that is interoperable with all of the supported languages and present benchmark data to compare the performance of all language bindings, highlighting the differences between languages that offer native struct support and an object-oriented interface with getter/setter methods. A case study shows how structs can help simplify the interfaces of scientific codes significantly.
2009-12-01
other services for early UNIX systems at Bell labs. In many UNIX based systems, the field added to ‘etc/ passwd ’ file to carry GCOS ID information was...charset, and external. struct options_main { /* Option flags */ opt_flags flags; /* Password files */ struct list_main * passwd ; /* Password file...object PASSWD . It is part of several other data structures. struct PASSWD { int id; char *login; char *passwd_hash; int UID
NASA Astrophysics Data System (ADS)
Saeidian, Hamid; Faraz, Sajjad Mousavi; Mirjafary, Zohreh; Babri, Mehran
2018-07-01
Recently, Blum from OPCW laboratory investigated HD, HS2, HS3 and higher polysulfides and their corresponding reactive intermediates by using Amsterdam Density Functional (ADF) calculations [22, 23]. In his presentation, he mentioned that analysis of MO energy levels for episulfonium ions of HD, HS2 and HS3 shows that the sulfur centered LUMOs for HS2 and HS3 are LUMO+1 for HD ion; and LUMOs energy levels of HS2 and HS3 are decreased by addition of polarizable sulfur atoms. He also showed that no four-membered sulfonium ion ring structures are formed for HS2, HS3 and higher polysulfides; and episulfonium ion is the only reactive intermediate for them.
DAMQT: A package for the analysis of electron density in molecules
NASA Astrophysics Data System (ADS)
López, Rafael; Rico, Jaime Fernández; Ramírez, Guillermo; Ema, Ignacio; Zorrilla, David
2009-09-01
DAMQT is a package for the analysis of the electron density in molecules and the fast computation of the density, density deformations, electrostatic potential and field, and Hellmann-Feynman forces. The method is based on the partition of the electron density into atomic fragments by means of a least deformation criterion. Each atomic fragment of the density is expanded in regular spherical harmonics times radial factors, which are piecewise represented in terms of analytical functions. This representation is used for the fast evaluation of the electrostatic potential and field generated by the electron density and nuclei, as well as for the computation of the Hellmann-Feynman forces on the nuclei. An analysis of the atomic and molecular deformations of the density can be also carried out, yielding a picture that connects with several concepts of the empirical structural chemistry. Program summaryProgram title: DAMQT1.0 Catalogue identifier: AEDL_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDL_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GPLv3 No. of lines in distributed program, including test data, etc.: 278 356 No. of bytes in distributed program, including test data, etc.: 31 065 317 Distribution format: tar.gz Programming language: Fortran90 and C++ Computer: Any Operating system: Linux, Windows (Xp, Vista) RAM: 190 Mbytes Classification: 16.1 External routines: Trolltech's Qt (4.3 or higher) ( http://www.qtsoftware.com/products), OpenGL (1.1 or higher) ( http://www.opengl.org/), GLUT 3.7 ( http://www.opengl.org/resources/libraries/glut/). Nature of problem: Analysis of the molecular electron density and density deformations, including fast evaluation of electrostatic potential, electric field and Hellmann-Feynman forces on nuclei. Solution method: The method of Deformed Atoms in Molecules, reported elsewhere [1], is used for partitioning the molecular electron density into atomic fragments, which are further expanded in spherical harmonics times radial factors. The partition is used for defining molecular density deformations and for the fast calculation of several properties associated to density. Restrictions: The current version is limited to 120 atoms, 2000 contracted functions, and l=5 in basis functions. Density must come from a LCAO calculation (any level) with spherical (not Cartesian) Gaussian functions. Unusual features: The program contains an OPEN statement to binary files (stream) in file GOPENMOL.F90. This statement has not a standard syntax in Fortran 90. Two possibilities are considered in conditional compilation: Intel's ifort and Fortran2003 standard. This latter is applied to compilers other than ifort (gfortran uses this one, for instance). Additional comments: The distribution file for this program is over 30 Mbytes and therefore is not delivered directly when download or e-mail is requested. Instead a html file giving details of how the program can be obtained is sent. Running time: Largely dependent on the system size and the module run (from fractions of a second to hours). References: [1] J. Fernández Rico, R. López, I. Ema, G. Ramírez, J. Mol. Struct. (Theochem) 727 (2005) 115.
Crystal structure and infrared spectra of dicesium trans-tetraaquadichlorochromium(III) chloride
NASA Astrophysics Data System (ADS)
Neumann, E.; Stefov, V.; Šoptrajanov, B.; Engelen, B.; Lutz, H. D.
2004-12-01
The crystal structure of dicesium trans-tetraaquadichlorochromium(III) chloride Cs 2Cr IIICl 5·4H 2O with trans-[M IIIX 2(H 2O) 4] + complex ions (space group C2/c, Z=4, a=1915.3(4) pm, b=614.1(1) pm, c=1392.0(3) pm, and β=118.24(3)°, final R1=0.0246 for 2100 unique reflections) was redetermined by single-crystal X-ray diffraction studies. It was found to crystallize in a 2c super structure of the structure reported previously (Inorg. Chem. 20 (1981) 1566; Inorg. Chem. 36 (1997) 2248). The obtained structure data now agree with the results of infrared spectroscopic studies, which has been confirmed in this work, namely that there are two different hydrate H 2O molecules in the structure. Phase transitions, static or dynamic disorder of the hydrate H 2O molecules, and space group C2/m proposed in the literature were ruled out. The coordinates of the four hydrogen positions derived from the X-ray data have been improved via the O-H distances derived from the wave numbers of the OD stretching modes of matrix isolated HDO molecules (2426, 2323, and 2306 cm -1, 263 K) by using the νOD versus rO-H correlation curve reported in the literature (J. Mol. Struct. 404 (1997) 63). The νOD versus rH⋯Cl correlation curve reported by Mikenda (J. Mol. Struct. 147 (1986) 1) should be improved, especially for strong hydrogen bonds. The two hydrate H 2O molecules of the title compound are strongly distorted with a weak and a relatively strong O-H⋯Cl hydrogen bond each thus intramolecular coupling of the two OH stretching vibrations to coupled ones is largely reduced and, hence, the wavenumbers of the OH and OD stretching modes of the HDO molecules mainly resemble those of the H 2O and D 2O molecules. The strength of the hydrogen bonds is in accordance with the predictions of the competitive and synergetic effects. Chloro ligands are weaker hydrogen bond acceptor groups than chloride ions.
Two new polytypes of 2,4,6-tribromobenzonitrile
Britton, Doyle; Noland, Wayland E.; Tritch, Kenneth J.
2016-01-01
Three polymorphs of 2,4,6-tribromobenzonitrile (RCN), C7H2Br3N, two of which are novel and one of which is a redetermination of the original structure first determined by Carter & Britton [(1972). Acta Cryst. B28, 945–950] are found to be polytypic. Each has a layer structure which differs only in the stacking of the layers. Each layer is composed of molecules associated through C≡N⋯Br contacts which form R 2 2(10) rings. Two such rings are associated with each N atom; one with each ortho-Br atom. No new polytypes of 1,3,5-tribromo-2-isocyanobenzene (RNC) were found but a re-determination of the original structure by Carter et al. [(1977). Cryst. Struct. Commun. 6, 543–548] is presented. RNC was found to be isostructural with one of the novel polytypes of RCN. Unit cells were determined for 23 RCN samples and 11 RNC samples. Polytypes could not be distinguished based on crystal habits. In all four structures, each molecule of the asymmetric unit lies across a mirror plane. PMID:26958382
Monohalogenated ferrocenes C5H5FeC5H4 X (X = Cl, Br and I) and a second polymorph of C5H5FeC5H4I
Romanov, Alexander S.; Mulroy, Joseph M.; Khrustalev, Victor N.; Antipin, Mikhail Yu.; Timofeeva, Tatiana V.
2009-01-01
The structures of the three title monosubstituted ferrocenes, namely 1-chloroferrocene, [Fe(C5H5)(C5H4Cl)], (I), 1-bromoferrocene, [Fe(C5H5)(C5H4Br)], (II), and 1-iodoferrocene, [Fe(C5H5)(C5H4I)], (III), were determined at 100 K. The chloro- and bromoferrocenes are isomorphous crystals. The new triclinic polymorph [space group P , Z = 4, T = 100 K, V = 943.8 (4) Å3] of iodoferrocene, (III), and the previously reported monoclinic polymorph of (III) [Laus, Wurst & Schottenberger (2005 ▶). Z. Kristallogr. New Cryst. Struct. 220, 229–230; space group Pc, Z = 4, T = 100 K, V = 924.9 Å3] were obtained by crystallization from ethanolic solutions at 253 and 303 K, respectively. All four phases contain two independent molecules in the unit cell. The relative orientations of the cyclopentadienyl (Cp) rings are eclipsed and staggered in the independent molecules of (I) and (II), while (III) demonstrates only an eclipsed conformation. The triclinic and monoclinic polymorphs of (III) contain nonbonded intermolecular I⋯I contacts, causing different packing modes. In the triclinic form of (III), the molecules are arranged in zigzag tetramers, while in the monoclinic form the molecules are arranged in zigzag chains along the a axis. Crystallographic data for (III), along with the computed lattice energies of the two polymorphs, suggest that the monoclinic form is more stable. PMID:19893225
NASA Astrophysics Data System (ADS)
Salehzadeh, Sadegh; Maleki, Farahnaz
2018-02-01
The title paper contains two types of calculations that are in disagreement with some basic concepts of chemistry. The first one is calculating a macroscopic amount of energy difference between one pair of enantiomers that is not correct. The second one is that the different bond orders for R and S stereoisomers and for different pathways of hyperconjugation/electron delocalization have been reported that both are impossible. In addition, the term electron transfer has been wrongly used for donor-acceptor orbital interactions inside one molecule where nothing is oxidized or reduced. Furthermore, the paper has missed some necessary comparisons with a previously published work of authors. There are also some technical problems in the title paper that are discussed in the present comment article.
Interactive Visual Simulation of Communication Systems. Volume 2
1988-04-29
struct( int non; ) ARM *PARAMPTR; Itypedef struct float x[8], y [8]; FILE *fp; mnt time; ) STATE, *STATEPTR; *psk8_dem (pparam, size,pstate,pstar) I...i*THETA); pstate-> y ~i]=sin(i*THETA) ; pstate->fp=fopen ( "graf .dat"l,"w"); pstate->time=0; Iif (length output_fifo(o)==maxlength-output_fifo(0...time) fprintf(pstate->fp,"\
Struct2Net: a web service to predict protein–protein interactions using a structure-based approach
Singh, Rohit; Park, Daniel; Xu, Jinbo; Hosur, Raghavendra; Berger, Bonnie
2010-01-01
Struct2Net is a web server for predicting interactions between arbitrary protein pairs using a structure-based approach. Prediction of protein–protein interactions (PPIs) is a central area of interest and successful prediction would provide leads for experiments and drug design; however, the experimental coverage of the PPI interactome remains inadequate. We believe that Struct2Net is the first community-wide resource to provide structure-based PPI predictions that go beyond homology modeling. Also, most web-resources for predicting PPIs currently rely on functional genomic data (e.g. GO annotation, gene expression, cellular localization, etc.). Our structure-based approach is independent of such methods and only requires the sequence information of the proteins being queried. The web service allows multiple querying options, aimed at maximizing flexibility. For the most commonly studied organisms (fly, human and yeast), predictions have been pre-computed and can be retrieved almost instantaneously. For proteins from other species, users have the option of getting a quick-but-approximate result (using orthology over pre-computed results) or having a full-blown computation performed. The web service is freely available at http://struct2net.csail.mit.edu. PMID:20513650
Forensic Memory Analysis for Apple OS X
2012-06-14
x86. Table 5. Template interface fields. Variable Python Type Description template dict template implementing the C stuct interface MBR_NAME str ...dictionary key, variable name for a struct member template[MBR_NAME] tuple dictionary value, a struct member description MBR_TYPE str C type of the...named member OFFSET int offset in bytes for the member SIZE int size in bytes for the member type FIELD str lsof field represented by member
The Rotation-Torsion Spectrum of CH_2DOH
NASA Astrophysics Data System (ADS)
Hilali, A. El; Coudert, L. H.; Margulès, L.; Motiyenko, R.; Klee, S.
2010-06-01
Due to the asymmetry of the CH_2D group, the internal rotation problem in the partially deuterated species of methanol CH_2DOH is a complicated one as, unlike in the normal species CH_3OH, the inertia tensor depends on the angle of internal rotation. The CH_2DOH species also displays a dense far infrared torsional spectrum difficult to assign. Recently 38 torsional subbands of CH_2DOH have been identified, but for most of them there is neither an assignment nor an analysis of their rotational structure. In this paper an analysis of the rotation-torsion spectrum of CH_2DOH will be presented. The rotational structure of 23 torsional subbands have been assigned. These subbands are Δ v_t &ge 1 perpendicular subbands with a value of v'_t up to 10b and values of K' and K'' ranging from 0 to 9. For all subbands, the Q-branch was assigned, for 3 subbands, the R- and P-branches could also be found. The results of the rotational analysis with an expansion in J(J+1) of the new subbands and of already observed ones will be presented. When available, microwave lines within the lower torsional level, recorded in this work or already measured, were added to the data set. A theoretical approach aimed at calculating the rotation-torsion energy levels has also been developed. It is based on an expansion in terms of rotation-torsion operators with C_s symmetry and accounts for the dependence of the inertia tensor on the angle of internal rotation. This approach will be used to carry out a preliminary global analyses of the wavenumbers and of the frequencies. Lauvergnat, Coudert, Klee, and Smirnov, J. Mol. Spec. 256 (2009) 204. Quade, Liu, Mukhopadhyay, and Su, J. Mol. Spec. 192 (1998) 378; Mukhopadhyay, J. Mol. Struct. 695-696 (2004) 357. Liu and Quade, J. Mol. Spec. 146 (1991) 252 Mukhopadhyay et al., J. Chem. Phys. 116 (2002) 3710.
First High Resolution IR Study of the νb{14} (a') A-Type Band Near 421.847 \\wn of 2-^{13}C-PROPENE
NASA Astrophysics Data System (ADS)
Daunt, S. J.; Grzywacz, Robert; Billinghurst, Brant E.
2017-06-01
This is is the first high resolution IR study of any band of the 2-^{13}C-propene species. There have been only two previous high resolution studies of vibration-rotation bands of the normal species. The band examined here is the νb{14} (A') CCC skeletal bending near 421.847 \\wn which has an A-Type asymmetric rotor structure. The spectra were recorded on the FTS at the Far-IR beamline of the Canadian Light Source with a resolution of Δν = 0.0009 \\wn. We have assigned and fitted around 2200 transitions and determined ground and upper state rotational constants. Lines with J up to 49 and K up to 12 were included. The subbands with K greater than 12 were perturbed and show torsional splittings that vary from small to extremely large. The fitting was done with the PGOPHER program of Colin Western. The GS constants are in good agreement with the MW constants reported recently by Craig, Groner and co-workers. Ainetschian, Fraser, Ortigoso & Pate, J. Chem. Phys. 100, 729 ff. (1994); Lafferty, Flaud & Herman, J. Mol. Struct. 780-781, 65 ff. (2006). Western, J. Quant. Spectrosc. Rad. Transf. 186, 221 ff. (2017). Paper M109, 71st ISMS Symposium (2016); J. Mol. Spectrosc. 328, 1-6 (2016).
StructRNAfinder: an automated pipeline and web server for RNA families prediction.
Arias-Carrasco, Raúl; Vásquez-Morán, Yessenia; Nakaya, Helder I; Maracaja-Coutinho, Vinicius
2018-02-17
The function of many noncoding RNAs (ncRNAs) depend upon their secondary structures. Over the last decades, several methodologies have been developed to predict such structures or to use them to functionally annotate RNAs into RNA families. However, to fully perform this analysis, researchers should utilize multiple tools, which require the constant parsing and processing of several intermediate files. This makes the large-scale prediction and annotation of RNAs a daunting task even to researchers with good computational or bioinformatics skills. We present an automated pipeline named StructRNAfinder that predicts and annotates RNA families in transcript or genome sequences. This single tool not only displays the sequence/structural consensus alignments for each RNA family, according to Rfam database but also provides a taxonomic overview for each assigned functional RNA. Moreover, we implemented a user-friendly web service that allows researchers to upload their own nucleotide sequences in order to perform the whole analysis. Finally, we provided a stand-alone version of StructRNAfinder to be used in large-scale projects. The tool was developed under GNU General Public License (GPLv3) and is freely available at http://structrnafinder.integrativebioinformatics.me . The main advantage of StructRNAfinder relies on the large-scale processing and integrating the data obtained by each tool and database employed along the workflow, of which several files are generated and displayed in user-friendly reports, useful for downstream analyses and data exploration.
1980-08-01
erosion resistant surface should be designed and con - structed on the downstream face after trees and trash have been removed. The owner should also...made by the Division of Waterways to con - struct a drop inlet spillway at North Dike in order to provide a more constant iake level. Plans (12 sheets...provide a more constant lake level. Plans (12 sheets) for this pro - * posal were prepared for the Division of Waterways by Robert G. Brown & Associ
We are Family: the Conformations of 1-FLUOROALKANES, C_nH2n+1F (n = 2,3,4,5,6,7,8)
NASA Astrophysics Data System (ADS)
Obenchain, Daniel A.; Orellana, W.; Cooke, S. A.
2016-06-01
he pure rotational spectra of the n = 5, 6, 7, and 8 members of the 1-fluoroalkane family have been recorded between 7 GHz and 14 GHz using chirped pulse Fourier transform microwave spectroscopy. The spectra have been analyzed and results will be presented and compared with previous work on the n= 2, 3, and 4 members. The lowest energy conformer for all family members has the common feature that the fluorine is in a gauche position relative to the alkyl tail for which all other heavy atom dihedral angles, where appropriate, are 180 degrees. For the n = 3 and higher family members the second lowest energy conformer has all heavy atom dihedral angles equal to 180 degrees. For each family member transitions carried by both low energy conformers were observed in the collected rotational spectra. Quantum chemical calculations were performed and trends in the energy separations between these two common conformers will be presented as a function of chain length. Furthermore, longer chain lengths have been examined using only quantum chemical calculations and results will be presented. M. Hayashi, M. Fujitake, T. Inagusa, S. Miyazaki, J.Mol.Struct., 216, 9-26, 1990 W. Caminati, A. C. Fantoni, F. Manescalchi, F. Scappini, Mol.Phys., 64, 1089 ,1988 L. B. Favero, A. Maris, A. Degli Esposti, P. G. Favero, W. Caminati, G. Pawelke, Chem.Eur.J., 6(16), 3018-3025, 2000
NASA Astrophysics Data System (ADS)
Kamnev, A. A.; Antonyuk, L. P.; Tugarova, A. V.; Tarantilis, P. A.; Polissiou, M. G.; Gardiner, P. H. E.
2002-06-01
Structural and compositional features of whole cells of the plant-growth-promoting rhizobacterium Azospirillum brasilense Sp7 under standard and heavy metal-stressed conditions are analysed using Fourier transform infrared (FTIR) spectroscopy and compared with the FT-Raman spectroscopic data obtained previously [J. Mol. Struct. 563-564 (2001) 199]. The structural spectroscopic information is considered together with inductively coupled plasma-mass spectrometric (ICP-MS) analytical data on the content of the heavy metal cations (Co2+, Cu2+ and Zn2+) in the bacterial cells. As a bacterial response to heavy metal stress, all the three metals, being taken up by bacterial cells from the culture medium (0.2 mM) in significant amounts (ca. 0.12, 0.48 and 4.2 mg per gram of dry biomass for Co, Cu and Zn, respectively), are shown to induce essential metabolic changes in the bacterium revealed in the spectra, including the accumulation of polyester compounds in bacterial cells and their enhanced hydration affecting certain IR vibrational modes of functional groups involved.
1HNMR study of methotrexate serum albumin (MTX SA) binding in rheumatoid arthritis
NASA Astrophysics Data System (ADS)
Sułkowska, A.; Maciążek-Jurczyk, M.; Bojko, B.; Równicka, J.; Sułkowski, W. W.
2008-11-01
Rheumatoid arthritis (RA) is an immunologically depended disease. It is characterized by a chronic, progressive inflammatory process. Methotrexate (4-amino-10-methylfolic acid, MTX) is the modifying drug used to treat RA. The aim of the presented studies is to determine the low affinity binding site of MTX in bovine (BSA) and human (HSA) serum albumin with the use of proton nuclear magnetic resonance ( 1HNMR) spectroscopy. The analysis of 1HNMR spectra of MTX in the presence of serum albumin (SA) allows us to observe the interactions between aromatic rings of the drug and the rings of amino acids located in the hydrophobic subdomains of the protein. On the basis of the chemical shifts σ [ppm] and the relaxation times T1 [s] of drug protons the hydrophobic interaction between MTX-SA and the stoichiometric molar ratio of the complex was evaluated. This work is a part of a spectroscopic study on MTX-SA interactions [A. Sułkowska, M. Maciążek, J. Równicka, B. Bojko, D. Pentak, W.W. Sułkowski, J. Mol. Struct. 834-836 (2007) 162-169].
The Equivalence of the Methyl Groups in Puckered 3,3-DIMETHYL Oxetane
NASA Astrophysics Data System (ADS)
Macario, Alberto; Blanco, Susana; Lopez, Juan Carlos
2016-06-01
The spectroscopic study of molecules with large amplitude vibrations have led to reconsider the concept of molecular structure. Sometimes identifying definite bond lengths and angles is not enough to reproduce the experimental data so one must have information on the large amplitude molecular vibration potential energy function and dynamics. 3,3-dimethyloxetane (DMO) has non-planar ring equilibrium configuration and a double minimum potential function for ring-puckering with a barrier of 47 cm-1. The observation of endocyclic 13C and 18O monosubstituted isotopologues allow to conclude that the ring is puckered. However an interesting feature was observed for the 13C substitutions at the methyl carbon atoms. While two different axial and equatorial 13C-methyl groups spectra are predicted from a rigid non-planar ring DMO model, only one species was found. The observed rotational transitions appear at a frequency close to the average of the frequencies predicted for each isotopologue. The observed lines have the same intensity as that found for the 13C_α isotopomer and double that that found for the 13C_β isotopomer.^c This behaviour evidences that the two methyl groups of DMO are equivalent as could be expected for a planar ring. In this work we show how consideration of the potential function and the path for ring puckering motion to calculate the proper kinetic energy terms allow to reproduce the experimental results. Ab initio computations at the CCSD/6-311++G(d,p) level, tested on related systems, have been done for this purpose. J. A. Duckett, T. L. Smithson, and H. Wieser, J. Mol. Spectrosc. 1978, 69 , 159; J. Mol. Struct. 1979, 56, 157 J. C. López, A. G. Lesarri, R. M. Villamañán and J. L. Alonso, J. Mol. Spectrosc. 1990, 141, 231 R. Sánchez, S. Blanco, A. Lesarri, J. C. López and J. L. Alonso, Phys. Chem. Chem. Phys. 2005, 7, 1157
StructAlign, a Program for Alignment of Structures of DNA-Protein Complexes.
Popov, Ya V; Galitsyna, A A; Alexeevski, A V; Karyagina, A S; Spirin, S A
2015-11-01
Comparative analysis of structures of complexes of homologous proteins with DNA is important in the analysis of DNA-protein recognition. Alignment is a necessary stage of the analysis. An alignment is a matching of amino acid residues and nucleotides of one complex to residues and nucleotides of the other. Currently, there are no programs available for aligning structures of DNA-protein complexes. We present the program StructAlign, which should fill this gap. The program inputs a pair of complexes of DNA double helix with proteins and outputs an alignment of DNA chains corresponding to the best spatial fit of the protein chains.
NASA Astrophysics Data System (ADS)
Maciążek-Jurczyk, M.; Sułkowska, A.; Bojko, B.; Równicka-Zubik, J.; Sułkowski, W. W.
2009-09-01
The monitoring of drug concentration in blood serum is necessary in multi-drug therapy. Mechanism of drug binding with serum albumin (SA) is one of the most important factors which determine drug concentration and its transport to the destination tissues. In rheumatoid diseases drugs which can induce various adverse effects are commonly used in combination therapy. Such proceeding may result in the enhancement of those side effects due to drug interaction. Interaction of phenylbutazone and colchicine in binding to serum albumin and competition between them in gout has been studied by proton nuclear magnetic resonance ( 1H NMR) technique. The aim of the study was to determine the low affinity binding sites, the strength and kind of interaction between serum albumin and drugs used in combination therapy. The study of competition between phenylbutazone and colchicine in binding to serum albumin points to the change of their affinity to serum albumin in the ternary systems. This should be taken into account in multi-drug therapy. This work is a subsequent part of the spectroscopic study on Phe-COL-SA interactions [A. Sułkowska, et al., J. Mol. Struct. 881 (2008) 97-106].
NASA Astrophysics Data System (ADS)
Keller, F.; Perrin, A.; Flaud, J.-M.; Johns, J. W. C.; Lu, Z.; Looi, E. C.
1998-10-01
The analysis of the ν6, ν7, ν8, and ν9bands of H15N16O3located at 646.9641, 578.4719, 743.6166, and 458.2917 cm-1, respectively, has been carried out in the 400-800 cm-1region using high-resolution Fourier transform spectra recorded at Ottawa. Using the ground state energy levels calculated from thev= 0 rotational constants of H15N16O3[A. P. Cox, M. C. Ellis, C. J. Attfield, and A. C. Ferris,J. Mol. Struct.320, 91-106 (1994)], it was possible to assign theA-type ν6and ν7bands and theC-type ν8and ν9bands of H15N16O3up to highJandKarotational quantum numbers. Thev6= 1,v7= 1, v8= 1, andv9= 1 experimental energy levels were then introduced in a least-squares fit calculation and precise upper state Hamiltonian constants (band centers and rotational constants) were determined allowing one to reproduce the infrared data to within the experimental uncertainty.
Lizunov, A Y; Gonchar, A L; Zaitseva, N I; Zosimov, V V
2015-10-26
We analyzed the frequency with which intraligand contacts occurred in a set of 1300 protein-ligand complexes [ Plewczynski et al. J. Comput. Chem. 2011 , 32 , 742 - 755 .]. Our analysis showed that flexible ligands often form intraligand hydrophobic contacts, while intraligand hydrogen bonds are rare. The test set was also thoroughly investigated and classified. We suggest a universal method for enhancement of a scoring function based on a potential of mean force (PMF-based score) by adding a term accounting for intraligand interactions. The method was implemented via in-house developed program, utilizing an Algo_score scoring function [ Ramensky et al. Proteins: Struct., Funct., Genet. 2007 , 69 , 349 - 357 .] based on the Tarasov-Muryshev PMF [ Muryshev et al. J. Comput.-Aided Mol. Des. 2003 , 17 , 597 - 605 .]. The enhancement of the scoring function was shown to significantly improve the docking and scoring quality for flexible ligands in the test set of 1300 protein-ligand complexes [ Plewczynski et al. J. Comput. Chem. 2011 , 32 , 742 - 755 .]. We then investigated the correlation of the docking results with two parameters of intraligand interactions estimation. These parameters are the weight of intraligand interactions and the minimum number of bonds between the ligand atoms required to take their interaction into account.
Xiao, Yiling; McElheny, Dan; Hoshi, Minako; Ishii, Yoshitaka
2018-01-01
Intense efforts have been made to understand the molecular structures of misfolded amyloid β (Aβ) in order to gain insight into the pathological mechanism of Alzheimer's disease. Solid-state NMR spectroscopy (SSNMR) is considered a primary tool for elucidating the structures of insoluble and noncrystalline amyloid fibrils and other amyloid assemblies. In this chapter, we describe a detailed protocol to obtain the first atomic model of the 42-residue human Aβ peptide Aβ(1-42) in structurally homogeneous amyloid fibrils from our recent SSNMR study (Nat Struct Mol Biol 22:499-505, 2015). Despite great biological and clinical interest in Aβ(1-42) fibrils, their structural details have been long-elusive until this study. The protocol is divided into four sections. First, the solid-phase peptide synthesis (SPPS) and purification of monomeric Aβ(1-42) is described. We illustrate a controlled incubation method to prompt misfolding of Aβ(1-42) into homogeneous amyloid fibrils in an aqueous solution with fragmented Aβ(1-42) fibrils as seeds. Next, we detail analysis of Aβ(1-42) fibrils by SSNMR to obtain structural restraints. Finally, we describe methods to construct atomic models of Aβ(1-42) fibrils based on SSNMR results through two-stage molecular dynamics calculations.
Conformational Studies of 1-OCTYNE from Rotational Spectroscopy
NASA Astrophysics Data System (ADS)
Maturo, Mark P.; Obenchain, Daniel A.; Melchreit, Robert; Cooke, S. A.; Novick, Stewart E.
2017-06-01
Alkanes of the form CH_3(CH_2)_nCH_3 generally favor ground state geometries that have co-planar carbon atoms. In this study, we have looked at a long chain hydrocarbon with a terminal carbon-carbon triple bond, viz., 1-octyne. Guided by the results of the 1-hexyne studies, three possible low energy conformers were studied which we reference as anti-anti (AA, straight chain), anti-gauche (AG, terminal methyl group is gauche), and gauche-anti (GA, ethyl group is gauche). An initial broadband chirp-pulse was performed between 7-13 GHz and a total of sixty-eight transitions were fit. Additional measurements on a Balle Flygare cavity instrument yielded an additional seventy-three lines belonging to three of the conformers. Transitions for all 8 of the singly substituted ^{13}C isotopologues, in natural abundance, have also been observed for the AA conformer. Ab-initio optimizations at the MP2/6-311++g(2d,2p) level of theory and basis set for these three conformers will be compared to experimental rotational constants. Structure determinations of the AA conformer will also be discussed. Atticks, K.; Bohn, R. K.; Michaels H. H. Int'l J. of Quantum Chem. 2001, 85, 514-519; Utzat, K.; Bohn, R. K.; Michaels H. H. J. Mol. Struct. 2007, 841, 22-27
Project Level Performance Database for Rigid Pavements in Texas, II
DOT National Transportation Integrated Search
2011-08-01
Over the years, the Texas Department of Transportation (TxDOT) has built a number of CRCP (continuously reinforced : concrete pavement) experimental sections to investigate the effects of design, materials, and construction variables on CRCP : struct...
Evaluation of hybrid slurry resulting from the introduction of additives to mineral slurry.
DOT National Transportation Integrated Search
2011-09-01
Drilled shaft construction often requires the use of drill slurry to maintain borehole stability during excavation : and concreting. Florida Department of Transportation (FDOT) specifications require the use of mineral slurry : for all primary struct...
Assessment of limestone blended cements for transportation applications : final report.
DOT National Transportation Integrated Search
2017-09-01
This research assessed the applicability of Type IL cements satisfying AASHTO M 240 specifications for use in transportation applications in place of Type I/II cements which satisfy AASHTO M 85 specifications for construction of transportation struct...
Large-scale laboratory observations of wave forces on a highway bridge superstructure.
DOT National Transportation Integrated Search
2011-10-01
The experimental setup and data are presented for a laboratory experiment conducted to examine realistic wave forcing on a highway bridge : superstructure. The experiments measure wave conditions along with the resulting forces, pressures, and struct...
FAA computer security : concerns remain due to personnel and other continuing weaknesses
DOT National Transportation Integrated Search
2000-08-01
FAA has a history of computer security weaknesses in a number of areas, including its physical security management at facilities that house air traffic control (ATC) systems, systems security for both operational and future systems, management struct...
Terahertz Rotational Spectroscopy of the so Radical
NASA Astrophysics Data System (ADS)
Martin-Drumel, M. A.; Cuisset, A.; Eliet, S.; Mouret, G.; Hindle, F.; Pirali, O.
2013-06-01
Sulfur monoxide SO (X^3Σ^-) is a well-known interstellar radical identified in a wide variety of astrophysical environments. Due to its high reactivity and its role in chemical reactions involving O and S atoms, SO is also a reaction intermediate in combustion processes and chemistry of the Earth atmosphere. We have recorded pure rotational transitions of SO in the THz spectral range using synchrotron-based Fourier-Transform (FT) FIR and continous wave (CW) THz techniques. A FT-FIR spectrum of SO has been recorded at the AILES beamline of SOLEIL synchrotron in the spectral range 44-93 wn using a resolution of 0.001 wn allowing an accuracy on line position of 0.00007 wn (≃ 2 MHz). A multipass absorption discharge cell aligned to an absorption path length of 24 m has been used. A continuous electrical discharge (1 A / 980 V) in a flowing mixture of H_2S, He, H_2 and air (respectively at pressure of 0.01, 1.15, 0.14 and 0.06 mbar) was used to produce SO. On this spectrum, 102 transitions of SO have been identified with N=31 to 65. Among the observed lines, 99 are detected for the first time (22 new transitions belong to the HIFI spectral windows). Due to our limited instrumental resolution, transitions involving N ranging from 31 to 43 show unresolved fine structure triplets. Recently, in order to observe all fine structure components in the HIFI spectral windows, we have recorded a high resolution CW-THz spectrum of SO. At the time of the writing, this spectrum was under analysis. C. A. Gottlieb and J. A. Ball, Astrophys. J. 184, L59 (1973) G.A. Blake et al., Astrophys. J. 315, 621 (1987) J. B. Burkholder et al., J. Mol. Spectrosc. 124, 379 (1987) M. A. Martin-Drumel et al., Rev. Sci. Instrum. 82, 113106 (2011) S. Eliet et al., J. Mol. Struct. 1006, 13 (2011)
NASA Astrophysics Data System (ADS)
Müller, Holger S. P.; Coutens, A.; Walters, A.; Grabow, J.-U.; Belloche, A.; Menten, K. M.; Schlemmer, S.
2009-06-01
We have carried out a molecular line survey of Sagittarius B2(N) in the 3 mm region with selected recordings at 2 and 1.3 mm to probe the chemical complexity in massive star-forming regions. Noteworthy results include the detection of aminoacetonitrile, a possible precursor of the aminoacid glycine, the detection of ^{13}C isotopologs of vinyl cyanide, and the detection of ethyl formate as well as normal-propyl cyanide. The heavy atoms in the latter molecule form a chain. An isomer with a branched structure, iso-propyl cyanide, also exists, but its rotational spectrum has only been recorded in few transitions up to 40 GHz. Therefore, laboratory measurements were extended. The molecule is rather asymmetric (κ = -0.5766) with a strong a-dipole moment component of 4.05 (2) D and a still sizable c-component of 1.4 (2) D.^e Measurements in Köln were carried out in selected regions between 40 and 600 GHz. Since the c-type transitions appeared to be weaker than predicted additional Stark (and also zero-field) measurements have been carried out in Hannover between 6 and 20 GHz. We will present results of these laboratory spectroscopic investigations as well as the outcome of a search for the molecule in our Sgr B2(N) line survey. A. Belloche, K. M. Menten, C. Comito, H. S. P. Müller, P. Schilke, J. Ott, S. Thorwirth, C. Hieret, Astron. Astrophys. 482 (2008) 179; Erratum 492 (2008) 796. H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, P. Schilke, J. Mol. Spectrosc. 251 (2008) 319. A. Belloche, R. T. Garrod, H. S. P. Müller, K. M. Menten, C. Comito, P. Schilke, Astron. Astrophys. (2009), accepted. G. E. Herberich, Z. Naturforsch. 22a (1967) 543. J. R. Durig, Y. S. Li, J. Mol. Struct. 21 (1974) 289.
Prospective Work for Alma: the Millimeterwave and Submillimeterwave Spectrum of 13C-GLYCOLALDEHYDE
NASA Astrophysics Data System (ADS)
Haykal, Imane; Margulès, Laurent; Huet, Therese R.; Motiyenko, Roman; Guillemin, J.-C.
2011-06-01
Glycolaldehyde has been identified in interstellar sources. The relative abundance ratios of the three isomers (acetic acid) : (glycolaldehyde) : (methylformate) were estimated . The detection of 13C_1 and 13C_2 isotopomers of methylformate has been recently reported in Orion, as a result of the detailled labororatory spectroscopic study. Therefore the spectroscopy of the 13C isotopomers of glycolaldehyde is investigated in laboratory in order to provide data for an astronomical search. The instrument ALMA will certainly be a good instrument to detect them. Up to now, only the microwave spectra of 13CH_2OH-CHO and of CH_2OH-13CHO have been observed several years ago in the 12-40 GHz range. Spectra of both species are presently recorded in Lille in the 150-950 GHz range with the new submillimetre-wave spectrometer based on harmonic generation of a microwave synthesizer source, using only solid-state devices, and coupled to a cell of 2.2 m length The absolute accuracy of the line positions is better than 30 KHz. The rotational structure of the ground state and of the three first excited vibrational states has been observed. Two 13C enriched samples were used. The analysis is in progress. This work is supported by the Programme National de Physico-Chimie du Milieu Interstellaire (PCMI-CNRS) and by the contract ANR-08-BLAN-0054 J. M. Hollis, S. N. Vogel, L. E. Snyder, et al., Astrophys. J. 554(2001) L81 R. A. H. Butler, F. C. De Lucia, D. T Petkie, et al., Astrophys. J. Supp. 134 (2001) 319 M. T. Beltran, C. Codella, S. Viti, R. Niri, R. Cesaroni, Astrophys. J. 690 (2009) L93. M. Carjaval, L. Margulès, B. Tercero et al., Astron. Astrophys. 500 (2009) 1109. K.-M. Marstokk and H. Møllendal, J. Mol. Struct. 16 (1973) 259. R. A. Motiyenko, L. Margulès, E. A. Alekseev et al., J. Mol. Spectrosc. 264 (2010) 94.
Effective Sealing and Monitoring of Small Movement Expansion Joints in Connecticut Bridges
DOT National Transportation Integrated Search
2017-03-01
One in nine bridges in the United States is rated as structurally deficient by the 2013 Infrastructure Report Card published by the American Society of Civil Engineers. One of the primary degradation factors that contribute to compromising the struct...
A review of federal and Minnesota laws on pedestrian, bicycle, and non-motorized transportation.
DOT National Transportation Integrated Search
2013-10-01
Minnesotas transportation system supports the movement and travel of people, vehicles, and freight : through a wide range of land-, water-, and air-based modes of transportation.21 This multimodal transportation system exists within a legal struct...
1983-08-01
cases, the crystalline regions are often lamellar in struct- rg and the lamellae fre- quently occur in some form of spherulitic morphology. Since, in a...12181 Dr. D. H. Whitmore Department of Materials Science Dr. A. P. B. Lever Northwestern University Chemistry Department Evanston, Illinois 60201 1 York
2005-10-31
Weierstall, K. Downing** and R. M. Glaeser*. J. Struct. Biol. 144, p209. 2003. 292 "A new thin-film phase of pentacene ". J. Wu and J. Spence. J...electron diffraction methods, we have discovered a new phase of pentacene , a material important for attempts to develop organic semiconductors
Assessing diversity and phytoremediation potential of seagrass in tropical region
USDA-ARS?s Scientific Manuscript database
Seagrass ecosystem is one of the most important resources in the coastal areas. Seagrasses support and provide habitats for many coastal organisms in tropical region. Seagrasses are specialized marine flowering plants that have adapted to the nearshore environment with heterogeneous landscape struct...
As an outcome of this project data on the applicability of protein polymer membranes for application to water desalination will be obtained. This will provide information on the stability and permeability of these membranes under simulated desalination conditions. The struct...
Fundamental Studies on Crashworthiness Design with Uncertainties in the System
2005-01-01
studied; examples include using the Response Surface Methods (RSM) and Design of Experiment (DOE) [2-4]. Space Mapping (SM) is another practical...Exposed to Impact Load Using a Space Mapping Technique,” Struct. Multidisc. Optim., Vol. 27, pp. 411-420 (2004). 6. Mayer, R. R., Kikuchi, N. and Scott
Fundamental Studies on Crashworthiness Design with Uncertainties in the System
2005-01-01
studied; examples include using the Response Surface Methods (RSM) and Design of Experiment (DOE) [2-4]. Space Mapping (SM) is another practical...to Impact Load Using a Space Mapping Technique," Struct. Multidisc. Optim., Vol. 27, pp. 411-420 (2004). 6. Mayer, R. R., Kikuchi, N. and Scott, R
Scaling Concolic Execution of Binary Programs for Security Applications
2013-08-01
Byte Array “<><><>” “<>” (89 times) 4/5 672 1 Sendmail 2 struct passwd (Linux) (“”,“root”,0,0,“root”,“”,“”) (“”,“root”,0,0,“rootroo”,“”,“”) 1/1 526
PKSOI Bulletin. Volume 2, Issue 4, July 2010
2010-07-01
are a “ blogger ” and would like to check out our blogs related to Peace and Stability Operations please visit our website and make comments. You may...leaders and officials. In several instances, the USG had con- structed beautiful facilities-a school and a clinic-without engaging sufficiently with
USDA-ARS?s Scientific Manuscript database
The temperature-dependent alteration of flagellar motility gene expression is critical for the foodborne pathogen Listeria monocytogenes to respond to a changing environment. In this study, a genetic determinant, L. monocytogenes f2365_0220 (lmof2365_0220), encoding a putative protein that is struct...
Electromagnetic Scattering from Two Dielectric Spheres: Comparison between Theory and Experiment,
1982-08-30
struct, a very complex computer program to perform the calculations. It should be noted that several errors (probably typographical) were disco - vered in...their equations and virtually all of them had to be rederived. In a future publication we will present a corrected set of equations along with several
DOT National Transportation Integrated Search
2005-02-01
Accelerated load testing of paved and unpaved roads is the application of a large number of load repetitions in a short period of time. This type of testing is an economic way to determine the behavior of roads and compare different materials, struct...
Synthesis and Characterization of Selected 4,4'-Diaminoalkoxyazobenzenes
The role of the -N(CH2CH20H)2 group in producing a mutagenic response from 4-«3-(2h) Uroxyethoxy)4-amino)phenylazo)-N,N-bis(2-hydroxyethyl)-aniline has been investigated. To accomplish this goal, a group ofsubstituted 4,4'-diaminoazobenzene dyes was synthesized, and their struct...
USDA-ARS?s Scientific Manuscript database
Soybeans (Glycine max L. Merill) and soy-based food products are major dietary sources of saponins. An oleanane triterpenoid saponin, soyasaponin Bh (1) containing a unique five-membered ring with a hemiacetal functionality together with seven known saponins were isolated from soybeans. Their struct...
NASA Astrophysics Data System (ADS)
Oller Aramayo, S. A.; Nallim, L. G.; Oller, S.
2013-12-01
This paper shows an integrated structural design optimization of a composite rotor-hydrofoil of a water current turbine by means the finite elements method (FEM), using a Serial/Parallel mixing theory (Rastellini et al. Comput. Struct. 86:879-896, 2008, Martinez et al., 2007, Martinez and Oller Arch. Comput. Methods. 16(4):357-397, 2009, Martinez et al. Compos. Part B Eng. 42(2011):134-144, 2010) coupled with a fluid-dynamic formulation and multi-objective optimization algorithm (Gen and Cheng 1997, Lee et al. Compos. Struct. 99:181-192, 2013, Lee et al. Compos. Struct. 94(3):1087-1096, 2012). The composite hydrofoil of the turbine rotor has been design using a reinforced laminate composites, taking into account the optimization of the carbon fiber orientation to obtain the maximum strength and lower rotational-inertia. Also, these results have been compared with a steel hydrofoil remarking the different performance on both structures. The mechanical and geometrical parameters involved in the design of this fiber-reinforced composite material are the fiber orientation, number of layers, stacking sequence and laminate thickness. Water pressure in the rotor of the turbine is obtained from a coupled fluid-dynamic simulation (CFD), whose detail can be found in the reference Oller et al. (2012). The main purpose of this paper is to achieve a very low inertia rotor minimizing the start-stop effect, because it is applied in axial water flow turbine currently in design by the authors, in which is important to take the maximum advantage of the kinetic energy. The FEM simulation codes are engineered by CIMNE (International Center for Numerical Method in Engineering, Barcelona, Spain), COMPack for the solids problem application, KRATOS for fluid dynamic application and RMOP for the structural optimization. To validate the procedure here presented, many turbine rotors made of composite materials are analyzed and three of them are compared with the steel one.
Zobnina, Veranika; Lambreva, Maya D; Rea, Giuseppina; Campi, Gaetano; Antonacci, Amina; Scognamiglio, Viviana; Giardi, Maria Teresa; Polticelli, Fabio
2017-01-01
In the photosystem II (PSII) of oxygenic photosynthetic organisms, the reaction center (RC) core mediates the light-induced electron transfer leading to water splitting and production of reduced plastoquinone molecules. The reduction of plastoquinone to plastoquinol lowers PSII affinity for the latter and leads to its release. However, little is known about the role of protein dynamics in this process. Here, molecular dynamics simulations of the complete PSII complex embedded in a lipid bilayer have been used to investigate the plastoquinol release mechanism. A distinct dynamic behavior of PSII in the presence of plastoquinol is observed which, coupled to changes in charge distribution and electrostatic interactions, causes disruption of the interactions seen in the PSII-plastoquinone complex and leads to the "squeezing out" of plastoquinol from the binding pocket. Displacement of plastoquinol closes the second water channel, recently described in a 2.9 Å resolution PSII structure (Guskov et al. in Nat Struct Mol Biol 16:334-342, 2009), allowing to rule out the proposed "alternating" mechanism of plastoquinol-plastoquinone exchange, while giving support to the "single-channel" one. The performed simulations indicated a pivotal role of D 1 -Ser264 in modulating the dynamics of the plastoquinone binding pocket and plastoquinol-plastoquinone exchange via its interaction with D 1 -His252 residue. The effects of the disruption of this hydrogen bond network on the PSII redox reactions were experimentally assessed in the D 1 site-directed mutant Ser264Lys.
Fitting the High-Resolution Spectroscopic Data for Ncncs
NASA Astrophysics Data System (ADS)
Kisiel, Zbigniew; Winnewisser, Brenda P.; Winnewisser, Manfred; De Lucia, Frank C.; Tokaryk, Dennis; Ross, Stephen Cary; Billinghurst, Brant E.
2014-06-01
NCNCS is a quasi-linear molecule that displays plentiful spectroscopic signatures of transition from the asymmetric top to the linear rotor regime. The transition takes place on successive excitation of the ν_7 bending mode at ca 80 cm-1. The unusual spectroscopic manifestations on crossing the barrier to linearity are explained by quantum monodromy and described quantitatively by the generalised semi-rigid bender Hamiltonian. Nevertheless, analysis to experimental accuracy of the extensive mm-wave spectrum of NCNCS recorded with the FASSST technique has only so far been achieved with the use of separate J(J+1) expansions for each (v_7, K_a) transition sequence.^c In addition, several selective perturbations identified between transition sequences in different vibrational levels^c are still unfitted. Presently we seek effective approximations to the vibration-rotation Hamiltonian that would allow combining multiple sequences into a fit, would allow a perturbation analysis, and could use mm-wave data together with high-resolution infrared measurements of NCNCS made at the Canadian Light Source. The understanding of effective fits to low-K_a subsets of rotational transitions in the FASSST spectrum has already allowed confident assignment of the 34S and both 13C isotopic species of NCNCS in natural abundance, as will be described. B.P.Winnewisser, et al., Phys. Rev. Lett. 95 243002 (2005). M.Winnewisser, et al., J. Mol. Struct. 798, 1 (2006). B.P.Winnewisser, et al., Phys. Chem. Chem. Phys. 12, 8158 (2010).
Clean Energy for the Commonwealth Powered by UMass
2009-04-15
Nanomagnetics Zeolite membranes Polymer-inorganic nanocomposites MEMS Nanostructured catalysts Plant Biotechnology Biochem., Cell wall struct., Agronomy Crambe...power management Low-power device networks Energy scavenging Flame Modeling Combustion chemistry Molecular-beam mass spectrometry Building Design...Thayumanavan, PhD. UMass Amherst Professor of Chemistry and Director, Fueling the Future Center for Chemical Innovation – Paul Osenar, PhD. Chief
2007-02-01
699. 5. Hanson, M. A., and Stevens, R. C. (2000) Cocrystal structure of synaptobrevin-ll bound to botulinum neurotoxin type B at 2.0 A resolution...R. C. (2000). Cocrystal structure of synaptobrevin-II bound to botulinum neurotoxin type B at 2.0 A resolution. Nature Struct. Biol. 7, 687–692. 23
Targeting Dysregulated Epigenetic Enzymes for Prostate Cancer Treatment
2016-10-01
decreased protein levels of SIRT2 leads to the inability to down-regulate the hyper -acetylated form of p300. SIRT2-dependent deacetylation of p300...nature06546. 32. Thompson PR, Wang D, Wang L, Fulco M, Pediconi N, Zhang D, et al. Regulation of the p300 HAT domain via a novel activation loop . Nat Struct
A Circuit Extraction System and Graphical Display for VLSI (Very Large Scale Integrated) Design.
1989-12-01
understandable as a net-list. The file contains information on the different physical layers of a polysilicon chip, not how these layers combine to form...yperc; struct vwsurf vsurf =DEFAULT_VWSURF(pixwt-ndd); stt-uct vwsurf vsurf2 DEFAULT-VWSURF(pixwfLndd); ma in) another[ Ol =IV while (anothler[0O = ’y
USDA-ARS?s Scientific Manuscript database
The present study describes the development of a real time Taqman polymerase chain reaction (PCR) assay using a fluorescent labeled probe for the detection and quantitation of chicken parvovirus (ChPV) in feces. The primers and probes were designed based on the nucleotide sequence of the non struct...
Poetic Praxis: Engaging Body, Mind, and Soul in the Social Foundations Classroom
ERIC Educational Resources Information Center
MacKenzie, Sarah K.,
2013-01-01
Across the space of this paper I seek to share a particular attempt to holistically engage students enrolled in a Social Foundations of Education course, in the process of de(con)structing knowledge, through the work of collectively creating found poetry. I do not seek to show right pedagogical practice; rather, it is my hope that this paper may…
1983-01-01
RENT OF FAC /FUEL SUPPLY 29 X299 AUTO TECHNIQUE BELGIQUE S A BELGIUM ARMY LEASE-RENT OF FAC /OTHER NON-BLDG STRUCT 31 HOFFMAN CO VIRGINIA ARMY LEASE...HARRISON & PALMI RIDGE ELECTRICAL E INC MISSOURI ARMY CONSTR: CONSTRUCTION/PARFING FACILITIES $ 123 SUSSEX ELECTRICO C MARYLAND ARMY CONSTR: CONSTRUCTION
NASA Astrophysics Data System (ADS)
Gnanasekar, Sharon Priya; Goubet, Manuel; Arunan, Elangannan; Georges, Robert; Soulard, Pascale; Asselin, Pierre; Huet, T. R.; Pirali, Olivier
2015-06-01
The H2O-CH3F complex could have two geometries, one with a hydrogen bond and one with the newly proposed carbon bond. While in general carbon bonds are weaker than hydrogen bonds, this complex appears to have comparable energies for the two structures. Infrared (IR) and microwave (MW) spectroscopic measurements using, respectively, the Jet-AILES apparatus and the FTMW spectrometer at the PhLAM laboratory, have been carried out to determine the structure of this complex. The IR spectrum shows the formation of the CH3F- H2O hydrogen bonded complex and small red-shifts in OH frequency most probably due to (CH3F)m-(H2O)n clusters. Noticeably, addition of CH_3F in the mixture promotes the formation of small water clusters. Preliminary MW spectroscopic measurements indicate the formation of the hydrogen bonded complex. So far, we have no experimental evidence for the carbon bonded structure. However, calculations of the Ar-CH3F complex show three energetically equivalent structures: a T-shape, a "fluorine" bond and a carbon bond. The MW spectrum of the (Ar)n-CH3F complexes is currently under analysis. Mani, D; Arunan, E. Phys. Chem. Chem. Phys. 2013, 15, 14377. Cirtog, M; Asselin, P; Soulard, P; Tremblay, B; Madebene, B; Alikhani, M. E; Georges, R; Moudens, A; Goubet, M; Huet, T.R; Pirali, O; Roy, P. J. Phys. Chem. A. 2011, 115, 2523 Kassi, S; Petitprez, D; Wlodarczak, G. J. Mol. Struct. 2000, 517-518, 375
The Millimeterwave Spectrum of n-BUTYL Cyanide
NASA Astrophysics Data System (ADS)
Ordu, Matthias H.; Müller, Holger S. P.; Lewen, Frank; Schlemmer, Stephan; Nez, Marc Nu; Walters, Adam
2011-06-01
The rotational spectrum of n-butyl cyanide (C_4H_9CN) was measured between 75 and 130 GHz using a novel all-solid-state spectrometer with a total absorption path of 44 m. In the course of the analysis of the spectrum, about 3000 transitions were assigned and a full set of quartic centrifugal distortion parameters with some sextic and octic terms could be determined for each of the three known conformers (anti-anti, anti-gauche(methyl end) and gauche(CN end)-anti). The work was motivated by the fact that n-butyl cyanide is likely to be found in interstellar hot core environments. This is indicated by the discovery of n-propyl cyanide (C_3H_7CN), the next smaller alkyl cyanide, in the ISM. The increased accuracy of the model, which will be additionally extended by future laboratory measurements around 200 GHz, may now be employed for a prediction of the spectrum up to 300 GHz with a feasible uncertainty for astronomic line surveys. Furthermore, there are two less abundant conformers, cis-gauche-gauche and trans-gauche-gauche, which have not yet been detected in the rotational spectrum. Due to the increased sensitivity of the new spectrometer, it seems possible now for the first time to identify their sectroscopic fingerprints in the recorded data. A. Belloche, R. T. Garrod, H. S. P.Müller, K. M. Menten, C. Comito, and P. Schilke, Astronomy & Astrophysics 499, 215 (2009) R. K. Bohn, J. L. Pardus, J. August, T. Brupbacher, W. Jäger, J. Mol. Struct. 413-414, 293 (1997)
Subsurface Assessment at McMurdo Station, Antarctica
2017-02-01
collected at the T-site for design and construction of a foundation for a wind turbine (after Oswell et al. 2010...foundation for a wind turbine (after Oswell et al. 2010). 5.3 Surface snowmelt and frost susceptibility The gravelly sand with silts found in this...maximum unfrozen density with low moisture content. Compaction of fill materials for con- structing wind turbine foundations at the T-site commenced
1991-08-15
Conversely, displays Atr con- past experience to the experimental stimuli. structed %xith normal density- controlled KDE cues but %ith 5. Excluding...frame. This 3Ndisplays, gray background is displayed’ on ail introduces 50% -scintillation (density control lion even frames (labelled 1:0). Other non ...video tapes were prepared, each of whsich contained all the experimental ASL signs but distributed 1 2 3 4 into dliffereint. filter groups . Eight
USDA-ARS?s Scientific Manuscript database
The cattle tick, Rhipicephalus (Boophilus) microplus, has a genome over 2.4 times the size of the human genome, and with over 70% of repetitive DNA, this genome would prove very costly to sequence at today's prices and difficult to assemble and analyze. BAC clones give insight into the genome struct...
Laser Spectroscopic Study of CaH in the B^2σ^+ and D^2σ^+ States
NASA Astrophysics Data System (ADS)
Watanabe, Kyohei; Uchida, Kanako; Kobayashi, Kaori; Matsushima, Fusakazu; Moriwaki, Yoshiki
2015-06-01
Calcium hydride is one of the abundant molecules in the stellar environment, and is considered as a probe of stellar analysis. Ab initio calculations have shown that the electronic excited states of CaH have complex potential curves. It is suggested that the B^2σ^+ state has an interesting double minimum potential due to the avoided crossing. Such a potential leads to drastic change of the rotational constants when the vibrational energy level goes across the potential barrier. Spectroscopic studies on CaH began in the 1920's, and many studies have been carried out since then. Bell et al. extensively assigned the D^2σ^+-X^2σ^+ bands in the UV region. Bernath's group has observed transitions in the IR and visible regions and identified their upper states as the A^2σ^+, B^2σ^+ and E^2σ^+ states. We have carried out a laser induced fluorescence (LIF) study in the UV region between 360 and 430 nm. We have produced CaH by using laser ablation of a calcium target in a hydrogen gas environment, then molecules have been excited by a second harmonic pulse of dye laser and the fluorescence from molecules have been detected through a monochromator. Detection of the D^2σ^+-X^2σ^+ bands already identified by Bell et al. indicates the production of CaH. In addition, many other bands have been also found and a few bands have been assigned by using the combination differences, the lower state of these bands have been confirmed to the vibrational ground state of X^2σ^+ state. We have tentatively assigned these bands as the B^2σ^+ -X^2σ^+ transition. We will discuss the assignment of these bands, together with the rotational constants comparing with those calculated from the ab initio potential. B. Barbuy, R. P. Schiavon, J. Gregorio-Hetem, P. D. Singh C. Batalha , Astron. Astrophys. Sippl. Ser. 101, 409 (1993). P. F. Weck and P. C .Stabcil, J. Chem. Phys. {118}, 9997 (2003). R. S. Mulliken, Phys. Rev. {25}, 509 (1925). G. D. Bell, M, Herman, J. W. C. Johns, and E. R. Peck, Physica Scripta {20}, 609 (1979). A. Shayesteh, K. A. Walker, I. Gordon, D. R. T. Appadoo, and P. F. Bernath, J. Mol. Struct. {695-696}, 23 (2004). R. S. Ram, K. Tereszchuk, I. E. Gordon, K. A. Walker, and P. F. Bernath, J. Mol. Spec. {266}, 86 (2011). G. Li, J. J. Harrison, R. S. Ram, C. M. Western, and P. F. Bernath Quant. Spectrosc. Rad. Transfer. {113}, 67 (2012). A. Shayesteh, R. S. Ram, and P. F. Bernath, J. Mol. Spec. {288}, 46 (2013).
Mammary Tumor Development: Stromal-Epithelial Interactions in Oncogenesis.
1996-09-01
differentiation, prolif- erative preneoplastic lesions, or invasive adenocarcinomas , depending on the promoter con- struct used and the animal’s age when...Zn). Virgin RSV-SGF transgenic mice showed marked preneoplastic MG ductal proliferation by 6 mo. By 8 mo., 1/3 had developed adenocarcinoma . Virgin...fat pRSGF Constitutively expressed Highly abnormal. None Normal Observed at 8 1/3 of mice show months of age invasive secretory adenocarcinoma SGF
Gender and Racial Equity in the U.S. Military Occupational Distribution
1988-09-30
suggested here could be operating. Discussion of those cited follows. Structural Discrimination The terms racism , sexism , institutional racism , and struct...a statistically significant level. Specifically, they were consistently underrepresented in the core technical occupations while White males...with Black enlisted men who number 198,000, or 30% of enlisted Army men, and 396,000, or 22% of enlisted men in the DoD Services (Quarterly Statistics
A Toolkit for Designing User Interfaces
1990-03-01
as the NPS IB can provide prototyping capability. Interface generators are available commercially for nearly every computing machine on the market ...structure which holds attributes of the message buffer window is shown in Figure 4.2. The variables nlines and nchars hold the number of lines in the...window its appearance of scrolling 46 /* define a type and structure for the message buffer */ struct messbuf( long nlines ; /* number of lines in the
1984-04-01
wavelengths. A direct application of such a laser is isotope separation. 2. For a brief status report of the Laboratory’s high- explosive flash...operation in the fall of 1982. in a 50-MeV Advanced Test Accelerator Facility (the ATA)1 that we are con- structing at our high- explosives test loca...chemical explosives in target-damage studies. Potential hazards associated with the ATA experiments were considered in choosing our site. LLNL’s
Intrasystem Analysis Program (IAP) Structural Design Study.
1981-06-01
accuracy constraints, and user competence . This report is designed to serve as a guide in con- structing procedures and identifying those aspects of the...parameters. 3.3.3 Userability The term "Userability" refers here to the level of competence assumed for an IAP analyst in need of a procedure. There...media the wires pass through is homogeneous along the length of the wires. Under these assumptions the wave propagation is predominantly tranverse
Simulation-Based Military Regional Anesthesia Training System
2008-12-01
and Zhang, X.Z., 2006 : Development of an MR-brake-based haptic device, Smart Mater. Struct., 15, 1960-66. Meislin, H., Criss, E. A. et al ., 1997...operations were superficial wounds or wounds to the extremities (Trunkey, 1983; Rush et al ., 2007). This was partly due to the advent of body... et al ., 1997). Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated to
Dynamic Multiaxial Response of a Hot-Pressed Aluminum Nitride
2012-01-05
Hutchinson, Adv. Appl . Mech. 29 (1992). [34] H. Ming-Yuan, J.W. Hutchinson, Int. J. Solids Struct. 25 (1989) 1053. [35] J. Salem , L. Ghosn, Int. J...Dynamic Multiaxial Response of a Hot- Pressed Aluminum Nitride by Guangli Hu, C. Q. Chen, K. T. Ramesh, and J. W. McCauley ARL-RP-0487...Laboratory Aberdeen Proving Ground, MD 21005-5066 ARL-RP-0487 June 2014 Dynamic Multiaxial Response of a Hot- Pressed Aluminum Nitride
Structures of the Procapsid and Mature Virion of Enterovirus 71 Strain 1095
Cifuente, Javier O.; Lee, Hyunwook; Yoder, Joshua D.; Shingler, Kristin L.; Carnegie, Michael S.; Yoder, Jennifer L.; Ashley, Robert E.; Makhov, Alexander M.; Conway, James F.
2013-01-01
Enterovirus 71 (EV71) is an important emerging human pathogen with a global distribution and presents a disease pattern resembling poliomyelitis with seasonal epidemics that include cases of severe neurological complications, such as acute flaccid paralysis. EV71 is a member of the Picornaviridae family, which consists of icosahedral, nonenveloped, single-stranded RNA viruses. Here we report structures derived from X-ray crystallography and cryoelectron microscopy (cryo-EM) for the 1095 strain of EV71, including a putative precursor in virus assembly, the procapsid, and the mature virus capsid. The cryo-EM map of the procapsid provides new structural information on portions of the capsid proteins VP0 and VP1 that are disordered in the higher-resolution crystal structures. Our structures solved from virus particles in solution are largely in agreement with those from prior X-ray crystallographic studies; however, we observe small but significant structural differences for the 1095 procapsid compared to a structure solved in a previous study (X. Wang, W. Peng, J. Ren, Z. Hu, J. Xu, Z. Lou, X. Li, W. Yin, X. Shen, C. Porta, T. S. Walter, G. Evans, D. Axford, R. Owen, D. J. Rowlands, J. Wang, D. I. Stuart, E. E. Fry, and Z. Rao, Nat. Struct. Mol. Biol. 19:424–429, 2012) for a different strain of EV71. For both EV71 strains, the procapsid is significantly larger in diameter than the mature capsid, unlike in any other picornavirus. Nonetheless, our results demonstrate that picornavirus capsid expansion is possible without RNA encapsidation and that picornavirus assembly may involve an inward radial collapse of the procapsid to yield the native virion. PMID:23637404
DOE Office of Scientific and Technical Information (OSTI.GOV)
Montemayor, Eric J.; Didychuk, Allison L.; Liao, Honghong
U6 small nuclear RNA (snRNA) is a key component of the active site of the spliceosome, a large ribonucleoprotein complex that catalyzes the splicing of precursor messenger RNA. Prior to its incorporation into the spliceosome, U6 is bound by the protein Prp24, which facilitates unwinding of the U6 internal stem-loop (ISL) so that it can pair with U4 snRNA. A previously reported crystal structure of the `core' of the U6 small nuclear ribonucleoprotein (snRNP) contained an ISL-stabilized A62G mutant of U6 bound to all four RNA-recognition motif (RRM) domains of Prp24 [Montemayoret al.(2014),Nature Struct. Mol. Biol.21, 544–551]. The structure revealedmore » a novel topology containing interlocked rings of protein and RNA that was not predicted by prior biochemical and genetic data. Here, the crystal structure of the U6 snRNP core with a wild-type ISL is reported. This complex crystallized in a new space group, apparently owing in part to the presence of an intramolecular cross-link in RRM1 that was not observed in the previously reported U6-A62G structure. The structure exhibits the same protein–RNA interface and maintains the unique interlocked topology. However, the orientation of the wild-type ISL is altered relative to the A62G mutant structure, suggesting inherent structural dynamics that may facilitate its pairing with U4. Consistent with their similar architectures in the crystalline state, the wild-type and A62G variants of U6 exhibit similar Prp24-binding affinities and electrophoretic mobilities when analyzed by gel-shift assay.« less
Contactless decontamination of hair samples: cannabinoids.
Restolho, José; Barroso, Mário; Saramago, Benilde; Dias, Mário; Afonso, Carlos A M
2017-02-01
Room temperature ionic liquids (ILs) have already been shown to provide efficient extraction media for several systems, and to capture volatile compounds, namely opiates. In this work, a novel, contactless, artefact-free extraction procedure for the removal of Δ 9 -tetrahrydrocannabinol (THC) from the surface of human hair is presented. To prepare in vitro cannabinoids-contaminated hair, samples were flushed with hashish smoke for 7 h. The decontamination experiments were carried at 100 °C for 24 h, according to the procedure previously described. Fifty-three ILs were screened and presented decontamination efficiencies ranging from 0 to 96 %. Although the majority of the ILs presented efficiencies above 90%, the 1-ethanol-3-methyl tetrafluoroborate (96%) was chosen for further process optimization. The Design of Experiments results demonstrated that all studied variables were significant for the process and the obtained optimum conditions were: 100 °C, 13 h and 175 mg of IL. In the work of Perrotin-Brunel et al. (J. Mol. Struct. 2011, 987, 67), it is demonstrated that, at 100 °C, full conversion of tetrahydrocannabinolic acid (THCA) into THC is obtained after 60 min. Since our decontamination takes place over 13 h at 100 °C, full conversion of THCA into THC is expected. Additionally, our method was compared with the method proposed by Cairns et al. (Forensic Sci. Int. 2004, 145, 97), through the analysis of 15 in vitro contaminated hair samples. The results demonstrated that with our method a mean extraction efficiency of 11 % higher was obtained. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
1981-03-23
25% Rotational angle - 350 degrees Temperature range - -65°C to + 125°C Vibration - 15 g Shock - 50 g Rotational load life - 25,000,000...structed of multi-layered metal foils, vacuum deposited on thin films of Mylar, Kapton, or similar plastics) slowly outgas and contaminate their own...armor. Intumescent coating is a paint derivative, which swells 5 to 50 times its original thickness when exposed to high temperatures ( 350 ° to 500
2014-04-01
can strongly affect formation of fatigue cracks. El Bartali et al. [7] quantified plastic strain at the grain scale in a duplex stainless steel and mea... Fatigue Fract Eng Mater Struct 2013. [7] El Bartali A, Aubin V, Degallaix S. Fatigue damage analysis in a duplex stainless steel by digital image...S. Surface observation and measurement techniques to study the fatigue damage micromechanisms in a duplex stainless steel . Int J Fatigue 2009;31:2049
Jayashree, B; Rajgopal, S; Hoisington, D; Prasanth, V P; Chandra, S
2008-09-24
Structure, is a widely used software tool to investigate population genetic structure with multi-locus genotyping data. The software uses an iterative algorithm to group individuals into "K" clusters, representing possibly K genetically distinct subpopulations. The serial implementation of this programme is processor-intensive even with small datasets. We describe an implementation of the program within a parallel framework. Speedup was achieved by running different replicates and values of K on each node of the cluster. A web-based user-oriented GUI has been implemented in PHP, through which the user can specify input parameters for the programme. The number of processors to be used can be specified in the background command. A web-based visualization tool "Visualstruct", written in PHP (HTML and Java script embedded), allows for the graphical display of population clusters output from Structure, where each individual may be visualized as a line segment with K colors defining its possible genomic composition with respect to the K genetic sub-populations. The advantage over available programs is in the increased number of individuals that can be visualized. The analyses of real datasets indicate a speedup of up to four, when comparing the speed of execution on clusters of eight processors with the speed of execution on one desktop. The software package is freely available to interested users upon request.
NASA Astrophysics Data System (ADS)
Pchelkin, Vladimir; Beloglazov, Mikhail
The distributions of the amplitudes of natural emissions of electromagnetic field in the Shu-mann resonance frequency range are investigated. From the data of Lovozero observatory daily variations of the number of overshoots of signal amplitude above given thresholds were con-structed. A possibility is discussed of applicability for the considered frequency range a known from the literature formula, which describes analytically the peak distribution of the spherics. We note the influence of magnetic disturbances on amplitude distribution function.
1979-12-18
feet, the crews were in- structed to take additional measurements. At very long beaches, such as at Presque Isle State Park, in Pennsylvania , the...REGULATION ON BEACHES AND BOATING FACILITIES- LAKES ERIE AND) ONTARIO AND CONNECTING WATERWAYS -I RECREATION BEACHES INVENTORY 3 December 18, 1979 Contract...CATALOG NUMBER 4. TITLE (and Subtitle) S. TYPE OF REPORT & PERIOD COVERED Impacts of Lake Level Regulation on Beaches and Boating Facilities--Lake Erie and
2008-05-01
4 ). The three-dimensional spatial orientation of the atoms for these resolved solution structures (Protein Data Bank accession codes: 2gt3...Crystal structure of the Escherichia coli peptide methionine sulphoxide reductase at 1.9 Å resolution . Struct. Fold. Des. 8: 1167 – 1178. 2 . Brot...sources (8). There is a 67% sequence identity between the E.coli and human MsrA ( 2 ). N-terminus C-terminus Figure 2 . Three-dimensional structure
2006-02-01
6. Hanson, M. A., and Stevens, R. C. (2000) Cocrystal structure of synaptobrevin-ll bound to botulinum neurotoxin type B at 2.0 A resolution, Nature...Hanson, R.C. Stevens, Cocrystal structure of synaptobre- vin-ll bound to botulinum neurotoxin type B at 2.0 Å resolution, Nat. Struct. Biol. 7 (2000...of the Glu212 carboxylate in the catalytic pathway, Biochemistry 43, 6637-6644. 4. Hanson, M. A., and Stevens, R. C. (2000) Cocrystal structure of
1992-05-22
Carbide because of its high thermal the mirror on its backside or edge. Shott Zerodur conductivity. Edge cooling causes a larger exceeded the limit by about...Characterization Angstrom-level noncontact profiling of mirrors for soft x-ray lithography............ 134 Paul Glenn Nonspecular Scattering from X-Ray...structed by patterning a Mo/Si Tropel Division of GCA Corporation. multilayer coated silicon wafer. The mirrors were coated at AT&T Bell The multilayer
Genome-Wide Analysis of Translational Control in Tuberous Sclerosis Complex
2012-07-01
particular non-AUG codons in the 5’UTR. However, these data was “noisy” and required a machine-learning algorithm to identify TIS codons. We develop...To investigate how nutrient signaling affects the folding of nascent chains, we used firefly luciferase (Luc) as a reporter because of its high...folding as the structural basis for the rapid de novo folding of firefly luciferase. Nat Struct Biol 6(7):697-705. 12. Gupta R, Kasturi P, Bracher A
Effect of Riblets on Pressure Recovery in a Straight-Walled Diffuser
1990-12-01
in the boundary layer velocity pro - file. As the flow continues to oppose the adverse pressure gradient, the fluid near the wall begins to flow in the...and was 37 inches long. The floor and ceiling of the test section were con - 3 structed of wood and the side panels were made of plexiglass. Both side...the diffuser remained fairly con - stant at 52 percent. The riblet results seem to follow the same trend, providing an approximate 35 percent increase in
Lamb Wave Propagation in a Restricted Geometry Composite PI-Joint Specimen (Preprint)
2011-11-01
adhesive, and were located along the length and height of the specimen as depicted in Figure 3. The sensors were 6.35 mm round disks of PZT , with a...in both cases for R1, R2, and R3. 3D Finite Element Model Geometry 200mm length 50mm width 140mm height x z y PZT Actuation Sensor...health monitoring using scanning laser vibrometry: III. Lamb waves for fatigue crack detection”, Smart Mater. Struct., Vol. 14, No. 6, 2005. 16
Avalanche Characteristics of Silicide Schottky Barrier Diodes
1988-01-01
respectively. Detectors should be con- structed of materials where a and 0 differ greatly, and then the multiplication should be initiated by the...8217 MASTER OF SCIENCE OSLD r In the Graduate College THE UNIVERSITY OF ARIZONA 1 9 8 7 ale L. STATEMENT BY AUTHOR This thesis has been submitted in...the head of the major department or the Dean of the Graduate College when in his or her judgement the proposed use of the material is in the interests
Efficient Estimation of Mutual Information for Strongly Dependent Variables
2015-05-11
the two possibilities: for a fixed dimension d and near- est neighbor parameter k, we find a constant ↵ k,d , such that if V̄ (i)/V (i) < ↵ k,d , then...also compare the results to several baseline estima- tors: KSG (Kraskov et al., 2004), generalized near- est neighbor graph (GNN) (Pál et al., 2010...Amaury Lendasse, and Francesco Corona. A boundary corrected expansion of the moments of near- est neighbor distributions. Random Struct. Algorithms
2006-11-22
multiple muta- tions were not studied, (iii) a vaccinia virus (VACV)- T7 system was used for transient expression, (iv) pseudotyped retrovi- ruses were used...those studies produced little to no detectable GP1 or GP2 in the transient VACV- T7 expression assays, whereas in our studies with the DNA con- structs...type GP2 was detected in pseudotyped retroviruses, a result seemingly in conflict with these authors’ findings with the VACV- T7 expression. Although
The Free Jet Microwave Spectrum of 2-PHENYLETHYLAMINE-WATER
NASA Astrophysics Data System (ADS)
Melandri, Sonia; Giuliano, B. Michela; Maris, Assimo; Caminati, Walther
2009-06-01
2-Phenylethylamine (PEA) is the parent structure for a variety of important compounds including dopamine, tyrosine, anphetamine and adrenaline. Due to the flexibility of the side chain, the conformational hypersurface of the isolated molecule contains several minima at relatively low energy. The conformational surface was studied by various spectroscopic and theoretical techniques and four of the five stable conformers were detected. The most stable conformers observed in isolated conditions are those in which the methylene side chain is folded into a gauche structure and the amino hydrogen is oriented towards the aromatic ring to form a weakly hydrogen bonded structure, while in the less stable conformers the amino group is in the anti position, thus the energy difference between the gauche and anti conformers (ca 4 kJ mol^{-1}) represents the energy associated with this weak interaction. Since bioactive molecules can be found in different environments including aqueous media and rotational spectroscopy coupled with high level ab initio calculations gives the most detailed structural picture, we studied the free jet microwave spectrum of the adducts formed between PEA and water in the region 60-78 GHz. The dominant spectrum is that of the 1:1 adduct of PEA and water where PEA is in its most stable gauche conformation and the water molecole is bound to the nitrogen lone pair. The orientation of the water molecole is such that the oxygen atom is closest (ca 2.5 Å) and equidistant from the ring and chain hydrogen atoms. The experimental data were complemented by ab initio calculations at the MP2/6311++G** level of theory; several stable conformations of the PEA-W have been characterized and the observed structure corresponds to the global minimum. The bonding of water seems to affect only slightly the structure of isolated PEA and the main structural parameters of the flexible amino side chain remain basically unaltered. Some lines still remain unassigned in the spectrum and we are hoping to assign them to a second conformational species of PEA-W. (a) S. J. Martinez, J. C. Alfano and D. H. Levy J. Mol. Struct. 158 82 1993. (b)P. D. Godfrey,L. D. Hatherley and R. D. Brown J. Am. Chem. Soc. 117 8204 1995. (c)S. Sun and E. R. Bernstein J. Am. Chem. Soc. 118 5086 1996. (d) J. A. Dickinson, M. R. Hockridge, R. T. Kroemer, E. G. Robertson, J. P. Simons, J. McCombie and M. Walker J. Am. Chem. Soc. 120 2622 1998. (e) J. C. Lopez, V. Cortijo, S. Blanco and J. Alonso PCCP 9 4521 2007.
1983-09-01
fluctuat- structed for the present purpose and a small amount of ing velocity components. The present experimental data milk was introduced into the...water flow. Finely dis- will also be compared with the nuerical results and the parsed milk droplets serve as the scattering particles._ experimental...correlation coefficient for the radial In the photoultipIler, I.e., f’ a 0.01. The mean mass transport Is 0.3 < Rvf < 0.4 though the momentum concentration
Characterization of Ignition and Combustion Properties of Nanowire-based Energetics
2013-07-23
Sannia, A. Cincotti, G. Cao, Chem. Eng. Sci. 54 (15–16) (1999) 3053–3061. [4] C. Rossi, K. Zhang, D. Esteve, P. Alphonse , P. Tailhades, C. Vahlas, J...94 (5) (2003) 2923–2929. [30] K. Zhang, C. Rossi, G.A.A. Rodriguez, C. Tenail- leau, P. Alphonse , Appl. Phys. Lett. 91 (11) (2007) 113117/1–113117/3...Pister, Smart Mater. Struct. 10(6), 1145 (2001). 8C. Rossi, K. Zhang, D. Esteve, P. Alphonse , P. Tailhades, and C. Vahlas, J. Microelectromech. Syst. 16
Advanced Numerical Methods for Simulating Nonlinear Multirate Lumped Parameter Models
1991-05-01
defining a Waveform: typedef struct Waveform char *name; /* character string of the name of the variable */ double tn; /* time of the beginning of the...A State-Space Approach, Reprinted from Proc. Third Ann. Allerton Conf. Circuits and Systems Thoery , 659-668, in Computer-Aided Circuit Design...kg/n 3) 1025.9 kg/m3 @ 15* C. v Kinematic Viscosity of Water (m2/sec) 1.19x10-6 m2/sec @ 15* C. G Acceleration of Gravity (m/sec2) 9.80665 m/sec 2 L
DOE Office of Scientific and Technical Information (OSTI.GOV)
Buchko, Garry W.; Daughdrill, Gary W.; De Lorimier, Robert
1999-12-28
Human XPA is an essential component in the multienzyme nucleotide excision repair (NER) pathway. The solution structure of the minimal DNA binding domain of XPA (XPA-MBD: M98-F219) was recently determined [Buchko et al. (1998) Nucleic Acids Res. 26, 2779-2788, Ikegami et al (1998) Nat. Struct. Biol. 5, 701-706] and shown to consist of a compact zinc-binding core and a loop-rich C-terminal subdomain connected by a linker sequence.
2008-05-01
2(b) is again 1.0 mm but has been reduced by an order of magnitude to 0.5 mm. It can be seen that the geometric resolution is now the limiting term...activity) of the system. The on-axis geometric efficiency for a pinhole is given by: (2) and represents the fraction of emitted photons that pass through...0.96 mm. The slight increase in the recon- structed diameter is due to the total resolution of the setup being limited by the geometric resolution which
2008-05-01
controlled processing. Bhanu-Prasad et al .37 conducted a systematic study of PM-processed 2124/SiC/30p aluminum composites 4 5 in which matrix alloy...Mater., 27, 173-178. [5] Wang A, Rack HJ (1991). Transition wear behavior of SiC-particulate- and SiC- whisker-reinforced 7091 Al metal matrix...modeling of particle distribution effects on fatigue in Al -SiCp composites. Mater. Sci. Eng. A, Struct. Mater. Prop. Microstruct. Process., 300, 113-124
2013-07-01
FabI, but share low sequence identity and are poorly inhibited by triclosan.25,26 S. pneumoniae and P. aeruginosa contain FabK,24 and Vibrio cholerae,27...with 0.2 mM IPTG. The cells were harvested after an overnight induction period at 17 °C. The cells were lysed and sonicated and loaded onto a nickel...of enoyl- (acyl-carrier protein) reductase, FabV, from Vibrio fischeri. Acta Crystallogr., Sect. F: Struct. Biol. Cryst. Commun. 2012, 68, 78−80. (27
NASA Astrophysics Data System (ADS)
Cordier, P.; Sun, X.; Fressengeas, C.; Taupin, V.
2015-12-01
A crossover between atomistic description and continuous representation of grain boundaries in polycrystals is set-up to model the periodic arrays of structural units by using dislocation and disclination dipole arrays along grain boundaries. Continuous modeling of the boundary is built by bottom-up processing, meaning that the strain, rotation, curvature, disclination and dislocation density fields are calculated by using the discrete atomic positions generated by molecular dynamics simulations. Continuous modeling of a 18.9° symmetric tilt boundary in copper [1] is conducted as a benchmark case. Its accuracy is validated by comparison with a similar recent technique [2]. Then, results on the 60.8° Mg2SiO4 tilt boundary [3-4] are presented. By linking the atomistic description with continuum mechanics representations, they provide new insights into the structure of the grain boundary. [1] Fressengeas, C., Taupin, V., Capolungo, L., 2014. Continuous modelling of the structure of symmetric tilt boundaries. Int. J. Solids Struct. 51, 1434-1441. [2] Zimmerman, J.A., Bammann, D.J., Gao, H., 2009. Deformation gradients for continuum mechanical analysis of atomistic simulations. Int. J. Solids Struct. 46, 238-253. [3] Cordier, P., Demouchy, S., Beausir, B., Taupin, V., Barou, F., Fressengeas, C., 2014. Disclinations provide the missing mechanism for deforming olivine-rich rocks in the mantle. Nature 507, 51-56. [4] Adjaoud, O., Marquardt, K., Jahn, S., 2012. Atomic structures and energies of grain boundaries in Mg2SiO4 forsterite from atomistic modeling. Phys. Chem. Miner. 39, 749-760.
NASA Astrophysics Data System (ADS)
Winnewisser, Manfred; Winnewisser, Brenda P.; De Lucia, Frank C.; Tokaryk, Dennis W.; Forthomme, Damien; Ross, Sephen C.; Billinghurst, Brant E.
2012-06-01
There are only pellet low resolution infrared spectra reported in the literature for sulfur di-cyanide S(CN){_2}, and none at all for cyanogen iso-thiocyanate, NCNCS. These two molecules are linked by a thermal isomerization reaction: NCSCN plus heat yields mainly NCNCS. Despite its difficult synthesis and its short kinetic life time, NCNCS is the best example so far of a quasi-linear molecule which clearly exhibits the distinctive monodromy-induced} dislocation of the ro-vibrational energy levels. The momentum maps (monodromy plots) of various physical quantities, such as effective rotational constants, ro-vibrational energies, dipole moment components etc. for NCNCS show at the top of the punt of the two-dimensional champaign-bottle potential energy function all the effects of quantum monodromy and exited state quantum phase transitions. For that reason it would be highly interesting to observe for NCNCS the high-resolution FIR bands of the lowest quasi-linear bending vibration. At the Canadian Light Source in May-June 2011 we first had to obtain the far-infrared spectrum of the precursor molecule S(CN)2 with the IFS125HR Bruker Fourier transform spectrometer. Six of the fundamental vibrational modes of this molecule have been observed and measured with the maximum resolution of 0.00096 cm-1. The analysis of the measured and assigned band systems is presently being carried out and will be reported in this contribution. The experimental strategy for synthesizing NCNCS and observing its FIR bands in a flow system through a multi-pass infrared absorption cell will also be discussed. B. P. Winnewisser, M. Winnewisser, I. R. Medvedev, F. C. De Lucia, S. C. Ross and J. Koput, Phys. Chem. Chem. Phys., 2010, 12, 8158-8189. D. Larese and F. Iachello, J. Mol. Struct., 1006 (2011) 611-628
A wireless strain sensor consumes less than 10 mW
NASA Astrophysics Data System (ADS)
Hew, Y.; Deshmukh, S.; Huang, H.
2011-10-01
This paper presents a wireless strain sensor that consumes about 9 mW. To achieve such an ultra-low power operation, a voltage-controlled oscillator (VCO) is utilized to convert the direct-current (DC) strain signal to a high frequency oscillatory signal. This oscillatory signal is then transmitted using an unpowered wireless transponder (Huang et al 2011 Smart Mater. Struct. 20 015017). A photocell-based energy harvester was developed to power the wireless strain sensor. The energy harvested from a flash light placed at 65 cm away is sufficient to power the wireless strain sensor continuously. The implementation of the wireless strain sensor and its characterization are presented.
Innovative intelligent technology of distance learning for visually impaired people
NASA Astrophysics Data System (ADS)
Samigulina, Galina; Shayakhmetova, Assem; Nuysuppov, Adlet
2017-12-01
The aim of the study is to develop innovative intelligent technology and information systems of distance education for people with impaired vision (PIV). To solve this problem a comprehensive approach has been proposed, which consists in the aggregate of the application of artificial intelligence methods and statistical analysis. Creating an accessible learning environment, identifying the intellectual, physiological, psychophysiological characteristics of perception and information awareness by this category of people is based on cognitive approach. On the basis of fuzzy logic the individually-oriented learning path of PIV is con- structed with the aim of obtaining high-quality engineering education with modern equipment in the joint use laboratories.
1978-06-01
FNO GlX GJP GMO HIP HJ( 11MN ILO JLN KLb: B ABCD AC? ADO AE1 AHL A J t’ Ar*N AD? CDL CEM CON CiJ ChP CN 0 DEN DFH D1K DJ? DMO EFJ ECK EHI’ EiD FUL FIN...Westlake Village, CA 91361 II.- CoN TIro I ING OFF 1C- NAME., AN C) AP"tOFF 12 R.. POFRT o AT " Air Force Office of Scientific Research September 1977...explains the techniques devel- oped by Box and Hunter (1961) and Daniel (1962) for con - structing Resolution IV screening designs from two Resolution
Watching proteins function with time-resolved x-ray crystallography
NASA Astrophysics Data System (ADS)
Šrajer, Vukica; Schmidt, Marius
2017-09-01
Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115-54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201-41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651-9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237-51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5-20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242-6, Barends et al 2015 Science 350 445-50, Pande et al 2016 Science 352 725-9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline challenges and further developments necessary to broaden the application of these methods to many important proteins and enzymes of biomedical relevance.
Watching proteins function with time-resolved x-ray crystallography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Šrajer, Vukica; Schmidt, Marius
Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in actionmore » and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline challenges and further developments necessary to broaden the application of these methods to many important proteins and enzymes of biomedical relevance.« less
Sulzenbacher, G; Driguez, H; Henrissat, B; Schülein, M; Davies, G J
1996-12-03
Endoglucanase I (EG I) is a cellulase, from glycosyl hydrolase family 7, which cleaves the beta-1,4 linkages of cellulose with overall retention of configuration. The structure of the EG I from Fusarium oxysproum, complexed to a nonhydrolyzable thiooligosaccharide substrate analogue, has been determined by X-ray crystallography at a resolution of 2.7 A utilizing the 4-fold noncrystallographic symmetry present in the asymmetric unit. The electron density map clearly reveals the presence of three glucosyl units of the inhibitor, consistent with the known number of sugar-binding subsites, located at the active site of the enzyme in the -2, -1, and +1 subsites, i.e., actually spanning the point of enzymatic cleavage. The pyranose ring at the point of potential enzymatic cleavage is clearly distorted from the standard 4C1 chair as was originally suggested for beta-retaining enzymes by Phillips [Ford, L.O., Johnson, L.N., Machin, P. A., Phillips, D.C., & Tijan, T. (1974) J. Mol. Biol, 88, 349-371]. The distortion observed goes beyond the "sofa" conformation observed in previous studies and results in a conformation whose salient feature is the resulting quasi-axial orientation for the glycosidic bond and leaving group, as predicted by stereoelectronic theory. An almost identical conformation has recently been observed in a complex of chitobiase with its unhydrolyzed substrate [Tews, I., Perrakis, A., Oppenheim, A., Dauter, Z., Wilson, K. S., & Vorgias, C. E. (1996) Nat. Struct. Biol. 3, 638-648]. The striking similarity between these two complexes extends beyond the almost identical pyranose ring distortion. The overlap of the two respective sugars places the enzymatic nucleophile of endoglucanase I in coincidence with the C2 acetamido oxygen of N-acetylglucosamine in the catalytic site of the chitobiase, substantiating the involvement of this group in the catalytic mechanism of chitobiase and related chitinolytic enzymes. The endoglucanase I complex with the thiosaccharide substrate analogue clearly illustrates the potential of nonhydrolyzable sulfur-linked oligosaccharides in the elucidation of substrate binding and catalysis by glycosyl hydrolases.
NASA Astrophysics Data System (ADS)
Sengupta, Tapan K.; Gullapalli, Atchyut
2016-11-01
Spinning cylinder rotating about its axis experiences a transverse force/lift, an account of this basic aerodynamic phenomenon is known as the Robins-Magnus effect in text books. Prandtl studied this flow by an inviscid irrotational model and postulated an upper limit of the lift experienced by the cylinder for a critical rotation rate. This non-dimensional rate is the ratio of oncoming free stream speed and the surface speed due to rotation. Prandtl predicted a maximum lift coefficient as CLmax = 4π for the critical rotation rate of two. In recent times, evidences show the violation of this upper limit, as in the experiments of Tokumaru and Dimotakis ["The lift of a cylinder executing rotary motions in a uniform flow," J. Fluid Mech. 255, 1-10 (1993)] and in the computed solution in Sengupta et al. ["Temporal flow instability for Magnus-robins effect at high rotation rates," J. Fluids Struct. 17, 941-953 (2003)]. In the latter reference, this was explained as the temporal instability affecting the flow at higher Reynolds number and rotation rates (>2). Here, we analyze the flow past a rotating cylinder at a super-critical rotation rate (=2.5) by the enstrophy-based proper orthogonal decomposition (POD) of direct simulation results. POD identifies the most energetic modes and helps flow field reconstruction by reduced number of modes. One of the motivations for the present study is to explain the shedding of puffs of vortices at low Reynolds number (Re = 60), for the high rotation rate, due to an instability originating in the vicinity of the cylinder, using the computed Navier-Stokes equation (NSE) from t = 0 to t = 300 following an impulsive start. This instability is also explained through the disturbance mechanical energy equation, which has been established earlier in Sengupta et al. ["Temporal flow instability for Magnus-robins effect at high rotation rates," J. Fluids Struct. 17, 941-953 (2003)].
NASA Astrophysics Data System (ADS)
Song, Di; Kang, Guozheng; Kan, Qianhua; Yu, Chao; Zhang, Chuanzeng
2015-08-01
Based on the experimental observations for the uniaxial low-cycle stress fatigue failure of super-elastic NiTi shape memory alloy microtubes (Song et al 2015 Smart Mater. Struct. 24 075004) and a new definition of damage variable corresponding to the variation of accumulated dissipation energy, a phenomenological damage model is proposed to describe the damage evolution of the NiTi microtubes during cyclic loading. Then, with a failure criterion of Dc = 1, the fatigue lives of the NiTi microtubes are predicted by the damage-based model, the predicted lives are in good agreement with the experimental ones, and all of the points are located within an error band of 1.5 times.
Emission of Polychlorinated Naphthalenes during Thermal Related Processes
NASA Astrophysics Data System (ADS)
Liu, Guorui; Zheng, Minghui; Du, Bing; Liu, Wenbin; Zhang, Bing; Xiao, Ke
2010-05-01
Due to the structural similarity of polychlorinated naphthalenes (PCNs) to those of dioxins, PCNs exhibit toxicological properties similar to dioxins (Olivero-Verbel et al., 2004). Based on their high toxicity, persistence, bioaccumulation, and long-distance transmission, PCNs were also selected as a candidate POP for the UN-ECE (United Nations Economic Commission for Europe) POP protocol (Lerche et al., 2002). In addition, some studies suggested that PCNs contributed a greater proportion of the dioxin-like activity than polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) contributed in some locations (Kannan et al., 1998). However, the identification and quantitation for PCN sources are very scarce compared with PCDD/Fs. Understanding the emission levels and developing the emission inventory of PCNs is important for regulatory and source reduction purposes. In this study, several potential sources were preliminarily investigated for PCN release. Coking process (CP), iron ore sintering (IOS), and electric arc furnace steel making units (AF) were selected due to their huge activity level of industrial production in China. Municipal solid waste incineration (MSWI) and medical waste incineration (MWI) were also investigated because of the possible high concentration of PCNs in stack gas. Two plants were investigated for each thermal related process, except for MWI with one incinerator was investigated. The stack gas samples were collected by automatic isokinetic sampling system (Isostack Basic, TCR TECORA, Milan Italy). Isotope dilution high resolution gas chromatography coupled with high resolution mass spectrometry (HRGC/HRMS) technique was used for the identification and quantitation of PCN congeners. The concentrations of PCNs from the selected thermal processes were determined in this study. The average concentrations of total PCNs were 26 ng Nm-3 for CP, 65 ng Nm-3 for IOS, 720 ng Nm-3 for AF, 443 ng Nm-3 for MSWI, and 45 ng Nm-3 for MWI. The emission factors of PCNs were derived, and the average values were 6 μg tonne-1 for CP, 42 μg tonne-1 for IOS, 2980 μg tonne-1 for AF, 1354 μg tonne-1 for MSWI, and 937 μg tonne-1 for MWI, which could be helpful for estimating the annual emission amounts of PCNs from the investigated sources. However, since the investigated plant numbers for each process are limited, there might be large uncertainties when developing the PCN emission inventory. From the obtained data in the preliminary investigation, it could be seen that these investigated sources are worthy of further concerns for PCN emission. Further investigation on PCN release from thermal related process is still in process. References Kannan, K., Imagawa, T., Blankenship, A.L., et al., 1998. Isomer-specific analysis and toxic evaluation of polychlorinated naphthalenes in soil, sediment, and biota collected near the site of a former chlor-alkali plant. Environ Sci Technol 32, 2507-2514. Lerche, D., van de Plassche, E., Schwegler, A., et al., 2002. Selecting chemical substances for the UN-ECE POP protocol. Chemosphere 47, 617-630. Olivero-Verbel, J., Vivas-Reyes, R., Pacheco-Londono, et al., 2004. Discriminant analysis for activation of the aryl hydrocarbon receptor by polychlorinated naphthalenes. J Mol Struc-Theochem 678, 157-161.
NASA Technical Reports Server (NTRS)
Wheeler, R. M.; Fitzpatrick, A. H.; Tibbitts, T. W.
2012-01-01
Potato (Solanum tuberosum L.) cvs. Russet Burbank, Denali, and Norland, were grown in environmental rooms controlled at approx 350 micro mol/mol (ambient during years 1987/1988) and 1000 micro mol/mol (enriched) CO2 concentrations. Plants and electric lamps were arranged to provide two irradiance zones, 400 and 800 micro mol/mol/square m/S PPF and studies were repeated using two photoperiods (12-h light / 12-h dark and continuous light). Leaf photosynthetic rates and leaf stomatal conductance were measured using fully expanded, upper canopy leaves at weekly intervals throughout growth (21 through 84 days after transplanting). Increasing the CO2 from approx 350 to 1000 micro mol/mol under the 12-h photoperiod increased leaf photosynthetic rates by 39% at 400 micro mol/mol/square m/S PPF and 27% at 800 micro mol/mol/square m/S PPF. Increasing the CO2 from approx 350 to 1000 micro mol/mol under continuous light decreased leaf photosynthetic rates by 7% at 400 micro mol/mol/square m/S PPF and 13% at 800 micro mol/mol/square m/S PPF. Increasing the CO2 from approx 350 to 1000 micro mol/mol under the 12-h photoperiod plants decreased stomatal conductance by an average of 26% at 400 micro mol/mol/square m/S PPF and 42% at 800 micro mol/mol/square m/S PPF. Under continuous light, CO2 enrichment resulted in a small increase (2%) of stomatal conductance at 400 micro mol/mol/square m/S PPF, and a small decrease (3%) at 800 micro mol/mol/square m/S PPF. Results indicate that CO2 enrichment under the 12-h photoperiod showed the expected increase in photosynthesis and decrease in stomatal conductance for a C3 species like potato, but the decreases in leaf photosynthetic rates and minimal effect on conductance from CO2 enrichment under continuous light were not expected. The plant leaves under continuous light showed more chlorosis and some rusty flecking versus plants under the 12-h photoperiod, suggesting the continuous light was more stressful on the plants. The increased rates of leaf photosynthesis with increased CO2 concentration paralleled trends in biomass production (published previously) but were not proportional to the biomass yields.
NASA Astrophysics Data System (ADS)
Baker, Catherine M.
Teaching people with disabilities tech skills empowers them to create solutions to problems they encounter and prepares them for careers. However, computer science is typically taught in a highly visual manner which can present barriers for people who are blind. The goal of this dissertation is to understand and decrease those barriers. The first projects I present looked at the barriers that blind students face. I first present the results of my survey and interviews with blind students with degrees in computer science or related fields. This work highlighted the many barriers that these blind students faced. I then followed-up on one of the barriers mentioned, access to technology, by doing a preliminary accessibility evaluation of six popular integrated development environments (IDEs) and code editors. I found that half were unusable and all had some inaccessible portions. As access to visual information is a barrier in computer science education, I present three projects I have done to decrease this barrier. The first project is Tactile Graphics with a Voice (TGV). This project investigated an alternative to Braille labels for those who do not know Braille and showed that TGV was a potential alternative. The next project was StructJumper, which created a modified abstract syntax tree that blind programmers could use to navigate through code with their screen reader. The evaluation showed that users could navigate more quickly and easily determine the relationships of lines of code when they were using StructJumper compared to when they were not. Finally, I present a tool for dynamic graphs (the type with nodes and edges) which had two different modes for handling focus changes when moving between graphs. I found that the modes support different approaches for exploring the graphs and therefore preferences are mixed based on the user's preferred approach. However, both modes had similar accuracy in completing the tasks. These projects are a first step towards the goal of making computer science education more accessible to blind students. By identifying the barriers that exist and creating solutions to overcome them, we can support increasing the number of blind students in computer science.
Correlation between vortex structures and unsteady loads for flapping motion in hover
NASA Astrophysics Data System (ADS)
Jardin, Thierry; Chatellier, Ludovic; Farcy, Alain; David, Laurent
2009-10-01
During the past decade, efforts were made to develop a new generation of unmanned aircrafts, qualified as Micro-Air Vehicles. The particularity of these systems resides in their maximum dimension limited to 15 cm, which, in terms of aerodynamics, corresponds to low Reynolds number flows ( Re ≈ 102 to 104). At low Reynolds number, the concept of flapping wings seems to be an interesting alternative to the conventional fixed and rotary wings. Despite the fact that this concept may lead to enhanced lift forces and efficiency ratios, it allows hovering coupled with a low-noise generation. Previous studies (Dickinson et al. in Science 284:1954-1960, 1999) revealed that the flow engendered by flapping wings is highly vortical and unsteady, inducing significant temporal variations of the loads experienced by the airfoil. In order to enhance the aerodynamic performance of such flapping wings, it is essential to give further insight into the loads generating mechanisms by correlating the spatial and temporal evolution of the vortical structures together with the time-dependent lift and drag. In this paper, Time Resolved Particle Image Velocimetry is used as a basis to evaluate both unsteady forces and vortical structures generated by an airfoil undergoing complex motion (i.e. asymmetric flapping flight), through the momentum equation approach and a multidimensional wavelet-like vortex parameterization method, respectively. The momentum equation approach relies on the integration of flow variables inside and around a control volume surrounding the airfoil (Noca et al. in J Fluids Struct 11:345-350, 1997; Unal et al. in J Fluids Struct 11:965-971, 1997). Besides the direct link performed between the flow behavior and the force mechanisms, the load characterization is here non-intrusive and specifically convenient for flapping flight studies thanks to its low Reynolds flows’ sensitivity and adaptability to moving bodies. Results are supported by a vortex parameterization which evaluates the circulation of the multiple vortices generated in such complex flows. The temporal evolution of the loads matches the flow behavior and hence reveals the preponderant inertial force component and that due to vortical structures.
Analysis of trace impurities in neon by a customized gas chromatography.
Yin, Min Kyo; Lim, Jeong Sik; Moon, Dong Min; Lee, Gae Ho; Lee, Jeongsoon
2016-09-09
Excimer lasers, widely used in the semiconductor industry, are crucial for analyzing the purity of premix laser gases for the purpose of controlling stable laser output power. In this study, we designed a system for analyzing impurities in pure neon (Ne) base gas by customized GC. Impurities in pure neon (H2 and He), which cannot be analyzed at the sub-μmol/mol level using commercial GC detectors, were analyzed by a customized pulsed-discharge Ne ionization detector (PDNeD) and a pressurized injection thermal conductivity detector using Ne as the carrier gas (Pres. Inj. Ne-TCD). From the results, trace species in Ne were identified with the following detection limits: H2, 0.378μmol/mol; O2, 0.119μmol/mol; CH4, 0.880μmol/mol; CO, 0.263μmol/mol; CO2, 0.162μmol/mol (PDNeD); and He, 0.190μmol/mol (Pres. Inj. Ne-TCD). This PDNeD and pressurized injection Ne-TCD technique thus developed permit the quantification of trace impurities present in high-purity Ne. Copyright © 2016. Published by Elsevier B.V.
Bai, Xiaoming; Bessa, Miguel A.; Melro, Antonio R.; ...
2016-10-01
The authors would like to inform that one of the modifications proposed in the article “High-fidelity micro-scale modeling of the thermo-visco-plastic behavior of carbon fiber polymer matrix composites” [1] was found to be unnecessary: the paraboloid yield criterion is sufficient to describe the shear behavior of the epoxy matrix considered (Epoxy 3501-6). The authors recently noted that the experimental work [2] used to validate the pure matrix response considered engineering shear strain instead of its tensorial counter-part, which caused the apparent inconsistency with the paraboloid yield criterion. A recently proposed temperature dependency law for glassy polymers is evaluated herein, thusmore » better agreement with the experimental results for this epoxy is observed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bai, Xiaoming; Bessa, Miguel A.; Melro, Antonio R.
The authors would like to inform that one of the modifications proposed in the article “High-fidelity micro-scale modeling of the thermo-visco-plastic behavior of carbon fiber polymer matrix composites” [1] was found to be unnecessary: the paraboloid yield criterion is sufficient to describe the shear behavior of the epoxy matrix considered (Epoxy 3501-6). The authors recently noted that the experimental work [2] used to validate the pure matrix response considered engineering shear strain instead of its tensorial counter-part, which caused the apparent inconsistency with the paraboloid yield criterion. A recently proposed temperature dependency law for glassy polymers is evaluated herein, thusmore » better agreement with the experimental results for this epoxy is observed.« less
Webb, Jena; Coomes, Oliver T; Mergler, Donna; Ross, Nancy A
2018-01-01
Polycyclic aromatic hydrocarbons (PAHs) are contaminants with carcinogenic effects but little is known about their presence in environments surrounding oil drilling operations and spills or exposure levels in nearby communities. The objective of this study was to characterize PAH levels in people living near oil drilling operations in relation to fish consumption, occupation, source of water and other socio-demographic characteristics. This pilot study examined PAH exposure by measuring 1-hydroxypyrene (1-OHP) in urine samples using high-performance liquid chromatography and fluorescence detection from 75 women and men in the Ecuadorian and Peruvian Amazon living near oil drilling operations and who answered a questionnaire collecting socio-demographic, occupational and dietary information. Data were analyzed using multiple linear regression models. The mean value of 1-OHP was 0.40 μmol/mol creatinine, 95% CI 0.32-0.46 μmol/mol creatinine. Women who used water from a surface source (for washing clothes or bathing) had almost twice the amount of 1-OHP in their urine (mean 1-OHP = 0.41 μmol/mol creatinine, 95% CI 0.28-0.54 μmol/mol creatinine, n = 23) as women who used water from either a well, a spring or rain (mean 1-OHP = 0.22 μmol/mol creatinine, 95% CI 0.11-0.34 μmol/mol creatinine, n = 6). Men who reported eating a bottom-dwelling species as their most commonly consumed fish (mean 1-OHP = 0.50 μmol/mol creatinine, 95% CI 0.36-0.64 μmol/mol creatinine, n = 31) had twice as much 1-OHP in their urine as men who reported a pelagic fish (mean 1-OHP = 0.25 μmol/mol creatinine, 95% CI 0.15-0.35 μmol/mol creatinine, n = 15), signaling either oral (fish consumption) or dermal (while standing in water fishing benthic species) exposure. More contact with surface water and benthic fish may result in higher levels of 1-OHP in human urine among the study population. Reducing the amount of oil and wastes entering the waterways in Andean Amazonia would be one way to reduce exposure.
Effects of CO2 on stomatal conductance: do stomata open at very high CO2 concentrations?
NASA Technical Reports Server (NTRS)
Wheeler, R. M.; Mackowiak, C. L.; Yorio, N. C.; Sager, J. C.
1999-01-01
Potato and wheat plants were grown for 50 d at 400, 1000 and 10000 micromoles mol-1 carbon dioxide (CO2). and sweetpotato and soybean were grown at 1000 micromoles mol-1 CO2 in controlled environment chambers to study stomatal conductance and plant water use. Lighting was provided with fluorescent lamps as a 12 h photoperiod with 300 micromoles m-2 s-1 PAR. Mid-day stomatal conductances for potato were greatest at 400 and 10000 micromoles mol-1 and least at 1000 micromoles mol-1 CO2. Mid-day conductances for wheat were greatest at 400 micromoles mol-1 and least at 1000 and 10000 micromoles mol-1 CO2. Mid-dark period conductances for potato were significantly greater at 10000 micromoles mol-1 than at 400 or 1000 micromoles mol-1, whereas dark conductance for wheat was similar in all CO2 treatments. Temporarily changing the CO2 concentration from the native 1000 micromoles mol-1 to 400 micromoles mol-1 increased mid-day conductance for all species, while temporarily changing from 1000 to 10000 micromoles mol-1 also increased conductance for potato and sweetpotato. Temporarily changing the dark period CO2 from 1000 to 10000 micromoles mol-1 increased conductance for potato, soybean and sweetpotato. In all cases, the stomatal responses were reversible, i.e. conductances returned to original rates following temporary changes in CO2 concentration. Canopy water use for potato was greatest at 10000, intermediate at 400, and least at 1000 micromoles mol-1 CO2, whereas canopy water use for wheat was greatest at 400 and similar at 1000 and 10000 micromoles mol-1 CO2. Elevated CO2 treatments (i.e. 1000 and 10000 micromoles mol-1) resulted in increased plant biomass for both wheat and potato relative to 400 micromoles mol-1, and no injurious effects were apparent from the 10000 micromoles mol-1 treatment. Results indicate that super-elevated CO2 (i.e. 10000 micromoles mol-1) can increase stomatal conductance in some species, particularly during the dark period, resulting in increased water use and decreased water use efficiency.
Maisuradze, Gia G; Leitner, David M
2007-05-15
Dihedral principal component analysis (dPCA) has recently been developed and shown to display complex features of the free energy landscape of a biomolecule that may be absent in the free energy landscape plotted in principal component space due to mixing of internal and overall rotational motion that can occur in principal component analysis (PCA) [Mu et al., Proteins: Struct Funct Bioinfo 2005;58:45-52]. Another difficulty in the implementation of PCA is sampling convergence, which we address here for both dPCA and PCA using a tetrapeptide as an example. We find that for both methods the sampling convergence can be reached over a similar time. Minima in the free energy landscape in the space of the two largest dihedral principal components often correspond to unique structures, though we also find some distinct minima to correspond to the same structure. 2007 Wiley-Liss, Inc.
Electronic and crystal structure of NiTi martensite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanati, M.; Albers, R.C.; Pinski, F.J.
1998-11-01
All of the first-principles electronic-structure calculations for the martensitic structure of NiTi have used the experimental atomic parameters reported by Michal and Sinclair [Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. {bold B37}, 1803 (1981)]. We have used first-principles, full-potential, linear muffin-tin orbital calculations to examine the total energy of all the experimental martensitic structures reported in the literature. We find that another crystal structure, that of Kudoh {ital et al.} [Acta Metall. Mater. {bold 33}, 2049 (1985)], has the lowest total energy at zero temperature. Ground-state and formation energies were calculated for all of the experimental structures. Total andmore » local densities of states were calculated and compared with each other for the structures of both Kudoh {ital et al.} and Michal and Sinclair thinsp {copyright} {ital 1998} {ital The American Physical Society}« less
Effect of Intramolecular Dispersion Interactions on the Conformational Preferences of Monoterpenoids
NASA Astrophysics Data System (ADS)
Loru, Donatella; Vigorito, Annalisa; Santos, Andreia; Tang, Jackson; Sanz, M. Eugenia
2017-06-01
The rotational spectra of several monoterpenoids have been reinvestigated with a 2-8 GHz chirped pulse FTMW spectrometer. Axial conformers, in addition to previously reported equatorial conformers, have been detected for carvone, perillaldehyde, and limonene. Observation of the ^{13}C isotopologues of these monoterpenoids in their natural abundances allowed the determination of r_s and r_0 structures. Axial conformers are stabilised by dispersion interactions between the six-membered ring of the monoterpenoids and the isopropenyl group. Comparison of experimental data with ab initio and density functional calculations shows that an accurate description of dispersion interactions is still a challenge for theoretical methods. J. R. Avilés Moreno, F. Partal Ureña, J. J. López González and T. R. Huet, Chem. Phys. Lett., 2009, 473, 17-20. J. R. Avilés Moreno, T. R. Huet and J. J. López González, Struct. Chem., 2013, 24, 1163-1170.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Drozhdin, A.I.; Brown, B.C.; Johnson, D.E.
2007-06-01
Results of modeling with the 3-D STRUCT and MARS15 codes of beam loss localization and related radiation effects are presented for the slipstacking injection to the Fermilab Main Injector. Simulations of proton beam loss are done using multi-turn tracking with realistic accelerator apertures, nonlinear fields in the accelerator magnets and time function of the RF manipulations to explain the results of beam loss measurements. The collimation system consists of one primary and four secondary collimators. It intercepts a beam power of 1.6 kW at a scraping rate of 5% of 5.5E+13 ppp, with a beam loss rate in the ringmore » outside the collimation region of 1 W/m or less. Based on thorough energy deposition and radiation modeling, a corresponding collimator design was developed that satisfies all the radiation and engineering constraints.« less
Calculation of Stress Intensity Factors for Interfacial Cracks in Fiber Metal Laminates
NASA Technical Reports Server (NTRS)
Wang, John T.
2009-01-01
Stress intensity factors for interfacial cracks in Fiber Metal Laminates (FML) are computed by using the displacement ratio method recently developed by Sun and Qian (1997, Int. J. Solids. Struct. 34, 2595-2609). Various FML configurations with single and multiple delaminations subjected to different loading conditions are investigated. The displacement ratio method requires the total energy release rate, bimaterial parameters, and relative crack surface displacements as input. Details of generating the energy release rates, defining bimaterial parameters with anisotropic elasticity, and selecting proper crack surface locations for obtaining relative crack surface displacements are discussed in the paper. Even though the individual energy release rates are nonconvergent, mesh-size-independent stress intensity factors can be obtained. This study also finds that the selection of reference length can affect the magnitudes and the mode mixity angles of the stress intensity factors; thus, it is important to report the reference length used with the calculated stress intensity factors.
Pyrolysis kinetics and thermal behavior of waste sawdust biomass using thermogravimetric analysis.
Mishra, Ranjeet Kumar; Mohanty, Kaustubha
2018-03-01
The present study reports pyrolysis behavior of three waste biomass using thermogravimetric analysis to determine kinetic parameters at five different heating rates. Physiochemical characterization confirmed that these biomass have the potential for fuel and energy production. Pyrolysis experiments were carried out at five different heating rates (5-25 °C min -1 ). Five model-free methods such as Kissinger-Akahira-Sunose (KAS), Ozawa-Flynn-Wall (OFW), Friedman, Coats-Redfern, and distributed activation energy (DAEM) were used to calculate the kinetic parameters. The activation energy was found to be 171.66 kJ mol -1 , 148.44 kJ mol -1 , and 171.24 kJ mol -1 from KAS model; 179.29 kJ mol -1 , 156.58 kJ mol -1 , and 179.47 kJ mol -1 from OFW model; 168.58 kJ mol -1 , 181.53 kJ mol -1 , and 184.61 kJ mol -1 from Friedman model; and 206.62 kJ mol -1 , 171.63 kJ mol -1 , and 160.45 kJ mol -1 from DAEM model for PW, SW, AN biomass respectively. The calculated kinetic parameters are in good agreement with other reported biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.
Abou-Elezz Fouad Mohammed, Khaled; Sarmiento-Franco, Luis; Santos-Ricalde, Ronald; Solorio-Sanchez, Javier Francisco
2012-06-01
This study aimed to evaluate the potential of Moringa oleifera fresh leaves (MOL) as feed supplement on the performance and egg quality of Rhode Island Red (RIR) hens under the tropical conditions of Yucatan, Mexico. Forty-eight RIR hens were allocated in 12 floor pen replicates each with four birds. Thereafter, the replicates were divided into three groups which were corresponded to ad libitum feed (control), ad libitum feed supplemented with MOL T1 (AL + MOL) and restricted feed amount (20% lower than control) with MOL T2 (RCD + MOL), respectively. T1 (AL + MOL) had higher egg laying rate (71.4% versus 66.6%), higher daily egg mass production (45.4 versus 41.9 g/day), lower feed intake (121.3 versus 127.5 g/day) and better feed conversion ratio (2.8 versus 3.2 g feed:g egg) versus control. T2 / (RCD + MOL) had lower values of body weight, egg laying rate, egg weight and egg mass, and recorded better feed conversion ratio than the control group. The control group recorded a higher percentage of pecked eggs versus T1 and T2 (6.5% versus 1.2% and 2.0 %). Similar intake of MOL (3.1 and 3.4 g DM/day) was recorded in T1 (AL + MOL) and T2 (RCD + MOL). Yolk color was improved significantly in T1 (AL + MOL) than both control and T2 (RCD + MOL), while T2 (RCD + MOL) had eggs with lower yolk and higher albumen percentages than the other two ad libitum groups. The results suggest that MOL could be used successfully as sustainable tropical feed resource for RIR hens.
NASA Technical Reports Server (NTRS)
Yorio, Neil C.; Wheeler, Raymond M.; Weigel, Russell C.
1995-01-01
Growth measurements were taken of potato plantlets (Solanum tuberosum L.) cvs. Norland (NL), Denali (DN), and Kennebec (KN), grown in vitro. Studies were conducted in a growth chamber, with nodal explants grown for 21 days on Murashige and Skoog salts with either 0, 1, 2, or 3% sucrose and capped with loose-fitted Magenta 2-way caps that allowed approximately 2.25 air exchanges/hour. Plantlets were exposed to either 100 or 300 micro mol/sq m/s photosynthetic photon flux (PPF), and the growth chamber was maintained at either 400 or 4000 micro mol/mol CO2. Regardless of PPF, all cvs. that were grown at 4000 micro mol/mol CO2 showed significant increases in total plantlet dry weight (TDW) and shoot length (SL) when sucrose was omitted from the media, indicating an autotrophic response. At 400 micro mol/mol CO2, all cvs. showed an increase in TDW and SL with increasing sucrose under both PPF levels. Within any sucrose treatment, the highest TDW for all cvs. resulted from 300 micro mol/sq m/s PPF and 4000 micro mol/mol CO2 At 4000 micro mol/mol CO2, TDW showed no further increase with sucrose levels above 1% for cvs. NL and DN at both PPF levels, suggesting that sucrose levels greater than 1% may hinder growth when CO2 enrichment is used.
Ureaplasma parvum causes hyperammonemia in a pharmacologically immunocompromised murine model.
Wang, X; Greenwood-Quaintance, K E; Karau, M J; Block, D R; Mandrekar, J N; Cunningham, S A; Mallea, J M; Patel, R
2017-03-01
A relationship between hyperammonemia and Ureaplasma infection has been shown in lung transplant recipients. We have demonstrated that Ureaplasma urealyticum causes hyperammonemia in a novel immunocompromised murine model. Herein, we determined whether Ureaplasma parvum can do the same. Male C3H mice were given mycophenolate mofetil, tacrolimus, and prednisone for 7 days, and then challenged with U. parvum intratracheally (IT) and/or intraperitoneally (IP), while continuing immunosuppression over 6 days. Plasma ammonia concentrations were determined and compared using Wilcoxon rank-sum tests. Plasma ammonia concentrations of immunosuppressed mice challenged IT/IP with spent broth (median, 188 μmol/L; range, 102-340 μmol/L) were similar to those of normal (median, 226 μmol/L; range, 154-284 μmol/L, p > 0.05), uninfected immunosuppressed (median, 231 μmol/L; range, 122-340 μmol/L, p > 0.05), and U. parvum IT/IP challenged immunocompetent (median, 226 μmol/L; range, 130-330 μmol/L, p > 0.05) mice. Immunosuppressed mice challenged with U. parvum IT/IP (median 343 μmol/L; range 136-1,000 μmol/L) or IP (median 307 μmol/L; range 132-692 μmol/L) had higher plasma ammonia concentrations than those challenged IT/IP with spent broth (p < 0.001). U. parvum can cause hyperammonemia in pharmacologically immunocompromised mice.
Simultaneous application of ethylene and 1-MCP affects banana ripening features during storage.
Botondi, Rinaldo; De Sanctis, Federica; Bartoloni, Serena; Mencarelli, Fabio
2014-08-01
In order to avoid the ripening blocking effect of 1-MCP (1-methylcyclopropene) on bananas when applied before ethylene commercial treatment, 1-MCP in combination with 'CD ethylene' (ethylene-cyclodextrin complex) was used in gas formulations: 300 nmol mol(-1) 1-MCP + 1200, 2400 or 4800 nmol mol(-1) ethylene (ETH). Control bananas received 1-MCP alone or 4800 nmol mol(-1) ethylene alone or no treatment. Treatments were done on overseas shipped bananas, at 14 °C, 90% relative humidity (RH), for 16 h; the bananas were stored under the same atmospheric conditions. After 4 or 12 days the bananas were commercially treated with 500 µmol mol(-1) ethylene. A 300 nmol mol(-1) 1-MCP treatment significantly blocked banana ripening in terms of physiological and technological parameters, inhibiting ethylene production and respiration, despite the commercial ethylene treatment. The application of 300 nmol mol(-1) 1-MCP + 1200 or 2400 nmol mol(-1) ethylene delayed ripening but with a regular pattern. A 300 nmol mol(-1) 1-MCP + 4800 nmol mol(-1) ethylene application did not delay ripening as did 4800 nmol mol(-1) ethylene treatment. The development of black spots was closely associated with advanced ripening/senescence of fruits. The combined 300 nmol mol(-1) 1-MCP + 1200 or 2400 nmol mol(-1) ethylene treatment appears to be a promising treatment to extend banana storage, following overseas shipping. © 2014 Society of Chemical Industry.
Li, Jiao; Wu, Dan-Dan; Zhang, Ji-Xiang; Wang, Jing; Ma, Jing-Jing; Hu, Xue; Dong, Wei-Guo
2018-05-07
To investigate the antitumor activity of α-hederin in hepatocellular carcinoma (HCC) cells and its underlying mechanisms in vitro and in vivo . SMMC-7721, HepG-2 and Huh-7 HCC cells were cultured in vitro and treated with α-hederin (0, 5 μmol/L, 10 μmol/L, 15 μmol/L, 20 μmol/L, 25 μmol/L, 30 μmol/L, 35 μmol/L, 40 μmol/L, 45 μmol/L, 50 μmol/L, 55 μmol/L, or 60 μmol/L) for 12 h, 24 h, or 36 h, and cell viability was then detected by the Cell Counting Kit-8. SMMC-7721 cells were treated with 0, 5 μmol/L, 10 μmol/L, or 20 μmol/L α-hederin for 24 h with or without DL-buthionine- S , R -sulfoximine (2 mmol/L) or N -acetylcysteine (5 mmol/L) pretreatment for 2 h, and additional assays were subsequently performed. Apoptosis was observed after Hoechst staining. Glutathione (GSH) and adenosine triphosphate (ATP) levels were measured using GSH and ATP Assay Kits. Intracellular reactive oxygen species (ROS) levels were determined by measuring the oxidative conversion of 2',7'-dichlorofluorescin diacetate. Disruption of the mitochondrial membrane potential was evaluated using JC-1 staining. The protein levels of Bax, Bcl-2, cleaved caspase-3, cleaved caspase-9, apoptosis-inducing factor and cytochrome C were detected by western blotting. The antitumor efficacy of α-hederin in vivo was evaluated in a xenograft tumor model. The α-hederin treatment induced apoptosis of HCC cells. The apoptosis rates in the control, low-dose α-hederin (5 μmol/L), mid-dose α-hederin (10 μmol/L) and high-dose α-hederin (20 μmol/L) groups were 0.90% ± 0.26%, 12% ± 2.0%, 21% ± 2.1% and 37% ± 3.8%, respectively ( P < 0.05). The α-hederin treatment reduced intracellular GSH and ATP levels, induced ROS, disrupted the mitochondrial membrane potential, increased the protein levels of Bax, cleaved caspase-3, cleaved caspase-9, apoptosis-inducing factor and cytochrome C, and decreased Bcl-2 expression. The α-hederin treatment also inhibited xenograft tumor growth in vivo . The α-hederin saponin induces apoptosis of HCC cells via the mitochondrial pathway mediated by increased intracellular ROS and may be an effective treatment for human HCC.
NASA Astrophysics Data System (ADS)
Rodrigues, Amanda Goulart; De Ros, Luiz Fernando; Neumann, Reiner; Borghi, Leonardo
2015-06-01
Abundant early diagenetic siderites occur as spherulites and rhombohedral microcrystalline and macrocrystalline crystals in the cores of the 2-MU-1-RJ well, drilled in the Paraíba do Sul Deltaic Complex, Rio de Janeiro (Brazil). The host sediments of the siderites are siliciclastic, hybrid, and carbonate deposits. Intense pedogenetic processes affected the siliciclastic sediments immediately after deposition, comprising clay illuviation, plants bioturbation, feldspar dissolution, and iron oxide/hydroxide precipitation. Siderite and pyrite are the main diagenetic constituents. The other diagenetic products are kaolinite, smectite, argillaceous and carbonate pseudomatrix, quartz overgrowths, diagenetic titanium minerals, jarosite, and iron oxides/hydroxides. Early diagenetic siderites were separated into four groups based on their elemental and stable isotopic composition, as well as on their paragenetic relationships with the other constituents and with the host sediments. Spherulitic to macrocrystalline siderites from group 1 are almost pure (average: 94.7 mol% FeCO3; 1.2 mol% MgCO3; 2.3 mol% CaCO3; 1.8 mol% MnCO3) and precipitated from meteoric porewaters in continental siliciclastic rocks under suboxic conditions (δ18Ovpdb values range in - 10.28 to - 5.57‰ and the δ13Cvpdb values in - 12.68 to - 4.33‰). Microcrystalline rhombohedral siderites from group 2 have zonation due to substantial Ca and Mg substitution (core average: 78.5 mol% FeCO3; 4.2 mol% MgCO3; 15.7 mol% CaCO3; 1.6 mol% MnCO3; edge average: 74.0 mol% FeCO3; 9.2 mol% MgCO3; 15.6 mol% CaCO3; 1.1 mol% MnCO3), and δ13Cvpdb and δ18Ovpdb values of + 0.17‰ and - 1.96‰, precipitated from marine porewaters in packstones/wackestones under methanogenic conditions. The group 3 is represented by irregular spherulitic siderites with moderate Ca and Mg substitutions (average: 80.2 mol% FeCO3; 7.9 mol% MgCO3; 11.3 mol% CaCO3; 0.6 mol% MnCO3), with δ18Ovpdb values ranging from - 5.96 to - 7.61‰ and δ13Cvpdb values ranging from - 5.15 to - 10.41‰. The group 4 microcrystalline siderites are magnesium-rich (average: 57.3 mol% FeCO3; 31.4 mol% MgCO3; 9.6 mol% CaCO3; 1.7 mol% MnCO3; δ13Cvpdb + 1.43‰ and δ18Ovpdb - 14.09‰). The group 3 and 4 siderites were formed from brackish porewater under suboxic conditions in hybrid and siliciclastic rocks. These variations in siderites are probably related to the Paraíba do Sul River dynamics, to sea level changes and to climatic variations that took place during the Quaternary.
Agapito, Filipe; Santos, Rui C; Borges dos Santos, Rui M; Martinho Simões, José A
2015-03-26
The gas-phase enthalpy of formation of cubane (603.4 ± 4 kJ mol(-1)) was calculated using an explicitly correlated composite method (W1-F12). The result obtained for cubane, together with the experimental value for the enthalpy of sublimation, 54.8 ± 2.0 kJ mol(-1), led to 548.6 ± 4.5 kJ mol(-1) for the solid-phase enthalpy of formation. This value is only 6.8 kJ mol(-1) higher than the 50-year-old original calorimetric result. The carbon-hydrogen bond dissociation enthalpy (C-H BDE) of cubane (438.4 ± 4 kJ mol(-1)), together with properties relevant for its experimental determination using gas-phase ion thermochemistry, namely the cubane gas-phase acidity (1704.6 ± 4 kJ mol(-1)), cubyl radical electron affinity (45.8 ± 4 kJ mol(-1)), cubane ionization energy (1435.1 ± 4 kJ mol(-1)), cubyl radical cation proton affinity (918.8 ± 4 kJ mol(-1)), cubane cation appearance energy (1099.6 ± 4 kJ mol(-1)), and cubyl ionization energy (661.2 ± 4 kJ mol(-1)), were also determined. These values were compared with those calculated for unstrained hydrocarbons (viz., methane, ethane, and isobutane). The strain energy of cubane (667.2 kJ mol(-1)) and cubyl radical (689.4 kJ mol(-1)) were independently estimated via quasihomodesmotic reactions. These values were related via a simple model to the C-H BDE in cubane. Taking into account the accuracy of the computational method, the comparison with high-precision experimental results, and the data consistency afforded by the relevant thermodynamic cycles, we claim an uncertainty better than ±4 kJ mol(-1) for the new enthalpy of formation values presented.
Phenytoin intoxication during concurrent diazepam therapy
Rogers, Howard J.; Haslam, Robert A.; Longstreth, James; Lietman, Paul S.
1977-01-01
Phenytoin elimination is a saturable process obeying Michaelis-Menten kinetics. Plasma phenytoin levels are not related linearly to dose, and small changes in enzyme activity produced by concurrent drug therapy could alter plasma levels. Two cases of phenytoin intoxication associated with simultaneous administration of diazepam are reported. Intravenous phenytoin infusions were given and the apparent Km and Vmax computed from the resulting plasma phenytoin levels. In one case `Km' and `Vmax' were 0.8 μmol/1 and 1.3 μmol/1/hour respectively during concurrent diazepam administration, and 50.3 μmol/1 and 4.4 μmol/1/hour after discontinuation of diazepam. In the second case phenytoin infusion with diazepam gave `Km' and `Vmax' values of 0.012 μmol/1 and 0.95 μmol/1/hour. Without diazepam these were 28.8 μmol/1 and 0.92 μmol/1/hour respectively. PMID:599366
40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.
Code of Federal Regulations, 2010 CFR
2010-07-01
... concentrations for intake-air humidity. You may use a time-weighted mean combustion air humidity to calculate this correction if your combustion air humidity remains within a tolerance of ±0.0025 mol/mol of the... equation: ER30AP10.095 Example: x NOxuncor = 700.5 µmol/mol x H2O = 0.022 mol/mol x NOxcor = 700.5 · (9.953...
40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.
Code of Federal Regulations, 2011 CFR
2011-07-01
... concentrations for intake-air humidity. You may use a time-weighted mean combustion air humidity to calculate this correction if your combustion air humidity remains within a tolerance of ±0.0025 mol/mol of the... equation: ER30AP10.095 Example: x NOxuncor = 700.5 µmol/mol x H2O = 0.022 mol/mol x NOxcor = 700.5 · (9.953...
Low-melting point heat transfer fluid
Cordaro, Joseph Gabriel; Bradshaw, Robert W.
2010-11-09
A low-melting point, heat transfer fluid made of a mixture of five inorganic salts including about 29.1-33.5 mol % LiNO.sub.3, 0-3.9 mol % NaNO.sub.3, 2.4-8.2 mol % KNO.sub.3, 18.6-19.9 mol % NaNO.sub.2, and 40-45.6 mol % KNO.sub.2. These compositions can have liquidus temperatures below 80.degree. C. for some compositions.
Ibrahim, Mohd Hafiz; Jaafar, Hawa Z E; Karimi, Ehsan; Ghasemzadeh, Ali
2014-01-01
A split plot 3 by 4 experiment was designed to investigate and distinguish the relationships among production of secondary metabolites, soluble sugar, phenylalanine ammonia lyase (PAL; EC 4.3.1.5) activity, leaf gas exchange, chlorophyll content, antioxidant activity (DPPH), and lipid peroxidation under three levels of CO2 (400, 800, and 1200 μ mol/mol) and four levels of light intensity (225, 500, 625, and 900 μ mol/m(2)/s) over 15 weeks in Labisia pumila. The production of plant secondary metabolites, sugar, chlorophyll content, antioxidant activity, and malondialdehyde content was influenced by the interactions between CO2 and irradiance. The highest accumulation of secondary metabolites, sugar, maliondialdehyde, and DPPH activity was observed under CO2 at 1200 μ mol/mol + light intensity at 225 μ mol/m(2)/s. Meanwhile, at 400 μ mol/mol CO2 + 900 μ mol/m(2)/s light intensity the production of chlorophyll and maliondialdehyde content was the highest. As CO2 levels increased from 400 to 1200 μ mol/mol the photosynthesis, stomatal conductance, f v /f m (maximum efficiency of photosystem II), and PAL activity were enhanced. The production of secondary metabolites displayed a significant negative relationship with maliondialdehyde indicating lowered oxidative stress under high CO2 and low irradiance improved the production of plant secondary metabolites that simultaneously enhanced the antioxidant activity (DPPH), thus improving the medicinal value of Labisia pumila under this condition.
NASA Technical Reports Server (NTRS)
Stanciel, K.; Mortley, D. G.; Hileman, D. R.; Loretan, P. A.; Bonsi, C. K.; Hill, W. A.
2000-01-01
The effects of elevated CO2 on growth, pod, and seed yield, and gas exchange of 'Georgia Red' peanut (Arachis hypogaea L.) were evaluated under controlled environmental conditions. Plants were exposed to concentrations of 400 (ambient), 800, and 1200 micromoles mol-1 CO2 in reach-in growth chambers. Foliage fresh and dry weights increased with increased CO2 up to 800 micromoles mol-1, but declined at 1200 micromoles mol-1. The number and the fresh and dry weights of pods also increased with increasing CO2 concentration. However, the yield of immature pods was not significantly influenced by increased CO2. Total seed yield increased 33% from ambient to 800 micromoles mol-1 CO2, and 4% from 800 to 1200 micromoles mol-1 CO2. Harvest index increased with increasing CO2. Branch length increased while specific leaf area decreased linearly as CO2 increased from ambient to 1200 micromoles mol-1. Net photosynthetic rate was highest among plants grown at 800 micromoles mol-1. Stomatal conductance decreased with increased CO2. Carboxylation efficiency was similar among plants grown at 400 and 800 micromoles mol-1 and decreased at 1200 micromoles mol-1 CO2. These results suggest that CO2 enrichment from 400 to 800 micromoles mol-1 had positive effects on peanut growth and yield, but above 800 micromoles mol-1 enrichment seed yield increased only marginally.
Liang, Junchao; Shen, Fengge; Xing, Mingxun; Deng, Xuming; Yu, Lu
2011-01-01
Background The targeting of Staphylococcus aureus biofilm structures are now gaining interest as an alternative strategy for developing new types of antimicrobial agents. Magnolol (MOL) shows inhibitory activity against S. aureus biofilms and Triton X-100-induced autolysis in vitro, although there are no data regarding the molecular mechanisms of MOL action in bacteria. Methodology/Principal Findings The molecular basis of the markedly reduced autolytic phenotype and biofilm inhibition triggered by MOL were explored using transcriptomic analysis, and the transcription of important genes were verified by real-time RT-PCR. The inhibition of autolysis by MOL was evaluated using quantitative bacteriolytic assays and zymographic analysis, and antibiofilm activity assays and confocal laser scanning microscopy were used to elucidate the inhibition of biofilm formation caused by MOL in 20 clinical isolates or standard strains. The reduction in cidA, atl, sle1, and lytN transcript levels following MOL treatment was consistent with the induced expression of their autolytic repressors lrgA, lrgB, arlR, and sarA. MOL generally inhibited or reversed the expression of most of the genes involved in biofilm production. The growth of S. aureus strain ATCC 25923 in the presence of MOL dose-dependently led to decreases in Triton X-100-induced autolysis, extracellular murein hydrolase activity, and the amount of extracellular DNA (eDNA). MOL may impede biofilm formation by reducing the expression of cidA, a murein hydrolase regulator, to inhibit autolysis and eDNA release, or MOL may directly repress biofilm formation. Conclusions/Significance MOL shows in vitro antimicrobial activity against clinical and standard S. aureus strains grown in planktonic and biofilm cultures, suggesting that the structure of MOL may potentially be used as a basis for the development of drugs targeting biofilms. PMID:22046374
In situ gas analysis for high pressure applications using property measurements
NASA Astrophysics Data System (ADS)
Moeller, J.; Span, R.; Fieback, T.
2013-10-01
As the production, distribution, and storage of renewable energy based fuels usually are performed under high pressures and as there is a lack of in situ high pressure gas analysis instruments on the market, the aim of this work was to develop a method for in situ high pressure gas analysis of biogas and hydrogen containing gas mixtures. The analysis is based on in situ measurements of optical, thermo physical, and electromagnetic properties in gas mixtures with newly developed high pressure sensors. This article depicts the calculation of compositions from the measured properties, which is carried out iteratively by using highly accurate equations of state for gas mixtures. The validation of the method consisted of the generation and measurement of several mixtures, of which three are presented herein: a first mixture of 64.9 mol. % methane, 17.1 mol. % carbon dioxide, 9 mol. % helium, and 9 mol. % ethane at 323 K and 423 K in a pressure range from 2.5 MPa to 17 MPa; a second mixture of 93.0 mol. % methane, 4.0 mol. % propane, 2.0 mol. % carbon dioxide, and 1.0 mol. % nitrogen at 303 K, 313 K, and 323 K in a pressure range from 1.2 MPa to 3 MPa; and a third mixture of 64.9 mol. % methane, 30.1 mol. % carbon dioxide, and 5.0 mol. % nitrogen at 303 K, 313 K, and 323 K in a pressure range from 2.5 MPa to 4 MPa. The analysis of the tested gas mixtures showed that with measured density, velocity of sound, and relative permittivity the composition can be determined with deviations below 1.9 mol. %, in most cases even below 1 mol. %. Comparing the calculated compositions with the generated gas mixture, the deviations were in the range of the combined uncertainty of measurement and property models.
Sun, B; Zhang, Y; Ding, M; Xi, Q; Liu, G; Li, Y; Liu, D; Chen, X
2018-02-01
This contribution reports the effects of Moringa oleifera leaves (MOLs) meal on the growth performances, nutrient digestibility, carcass trait, meat quality, antioxidant capacity and biochemical parameters of growing New Zealand white rabbits. The MOL was substituted for alfalfa meal at levels of 0, 10%, 20% and 30% to obtain respective diets MOL0, MOL10, MOL20 and MOL30. Each treatment was replicated five times with 10 rabbits per replicate. Results showed the average daily weight gain (ADWG) and feed conversion ratio (FCR) of rabbits fed MOL20 diet were significantly better (p < 0.05) than those of other three dietary groups. Liver and spleen index of rabbits fed MOL20 and MOL30 diets was significantly higher (p < 0.05) than that of the groups fed with lower M. oleifera leaves (MOL0, MOL10). The meat drip loss of rabbits fed with diet MOL10 was significantly lower (p < 0.05) than that of rabbits fed other diets. All rabbits fed MOL dietary groups had lower (p < 0.05) shear force of longissimus dorsi than the group without M. oleifera leaves. No significant differences were found in the digestibility of crude fibre (CF), crude fat (EE), ash, crude protein (CP) and nitrogen-free extract (NFE) among the dietary groups. Moringa oleifera leaves also have a significant impact on serum albumin (ALB), low-density lipoprotein cholesterol (LDLC), triiodothyroxine (T 3 ) and tetraiodothyroxine (T 4 ) values and the activity of superoxide dismutase (SOD) and catalase (CAT) in serum and liver. The results indicated that M. oleifera leaves could be developed as a good feed source, and it not only could substitute for alfalfa meal well but also has a significant effect on growth performance, meat quality, antioxidant and biochemical parameters of rabbits. © 2017 Blackwell Verlag GmbH.
Jost, Tobias; Zipprich, Alexander; Glomb, Marcus A
2018-04-18
Methylglyoxal is a major 1,2-dicarbonyl compound in vivo and leads to nonenzymatic protein modifications, known as advanced glycation endproducts. Especially long-lived proteins like collagen are prone to changes of the mechanical or biological function, respectively, by accumulation of Maillard-derived modifications. Specifically, the resulting nonenzymatic cross-link structures in parallel to the natural maturation process of collagen fibrils lead to complications with age or during disease. A novel lysine-lysine amide cross-link derived from methylglyoxal, 2,15-diamino-8-methyl-9-oxo-7,10-diaza-1,16-hexadecanedioic acid, named MOLA, was synthesized and identified in vitro and in vivo. Tail tendons of young, adult, and old rats (3, 12, and 22 months) were enzymatically digested prior to analysis of acid-labile glycation products via liquid chromatography-tandem mass spectrometry (LC-MS/MS). As a result, nine monovalent amino acid modifications, mostly originating from methylglyoxal (36 μmol/mol leucine-equivalents in total), and four glycation cross-links (0.72 μmol/mol glucosepane, 0.24 μmol/mol DODIC (3-deoxyglucosone-derived imidazoline cross-link), 0.04 μmol/mol MODIC (methylglyoxal-derived imidazoline cross-link), 0.34 μmol/mol MOLA) were quantitated in senescent tendon collagen. The results correlated with increased tail tendon breaking time from 10 to 190 min and indicate that methylglyoxal is a major player in the aging process of connective tissue.
NASA Astrophysics Data System (ADS)
Jiang, Qiaowen; Cao, Zhimin; Wang, Daoru; Li, Yuanchao; Wu, Zhongjie; Ni, Jianyu
2017-12-01
Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set (1902 to 2005), the annual variations in Ba/Ca and Mn/Ca ratios of Porites lutea skeletons at an eastern offshore area of Hainan Island (19°12´28.4´´N, 110°37´38.8´´E) were analyzed using inductively coupled plasma-optic emission spectrometry (ICP-OES). The analysis results showed that Ba/Ca ratios varied from a minimum of 3.120 μmol mol-1 in 1903 to a maximum of 10.064 μmol mol-1 in 1944, with an average of 5.256 μmol mol-1. Mn/Ca ratios varied from 0.206 to 5.708 μmol mol-1 with an annual average of 1.234 μmol mol-1, with peak values in 2001, 1964 and 1932, that correlated with strong rainfall events caused by typhoons. Variation in Ba/Ca and Mn/Ca ratios were compared with available river discharge and precipitation records, providing insight into past climatological events. Human activities and their indirect effects could impact the strength of the relationship between Ba/Ca and Mn/Ca ratios and observed precipitation and terrestrial input in the future.
Atmospheric air pollutants: CO in Nitrogen, 5 μmol/mol
NASA Astrophysics Data System (ADS)
Konopelko, L. A.; Pankratov, V. V.; Pankov, A. A.; Ivahnenko, B. V.; Efremova, O. V.; Bakovec, N. V.; Mironchik, A. M.; Aleksandrov, V. V.
2017-01-01
This article presents the report on the COOMET supplementary comparison "Atmospheric air pollutants: CO in Nitrogen, 5 μmol/mol". Carbon monoxide (CO) is present in atmosphere due to different natural and anthropogenic sources. CO is a toxic gas and in concentrations higher than (3-5) μmol/mol it is hazardous to human health. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Abd Wahid, Muhamad Azhar; Megat Mohd Noor, Megat Johari; Goto, Masafumi; Sugiura, Norio; Othman, Nor'azizi; Zakaria, Zuriati; Ahmad Mohammed, Thamer; Jusoh, Ahmad; Hara, Hirofumi
2017-08-01
The natural coagulant Moringa oleifera lectin (MoL) as cationic protein is a promising candidate in coagulation process of water treatment plant. Introducing the gene encoding MoL into a host, Pichia pastoris, to secrete soluble recombinant protein is assessed in this study. Initial screening using PCR confirmed the insertion of MoL gene, and SDS-PAGE analysis detected the MoL protein at 8 kDa. Cultured optimization showed the highest MoL protein at 520 mg/L was observed at 28 °C for 144 h of culturing by induction in 1% methanol. Approximately, 0.40 mg/mL of recombinant MoL protein showed 95 ± 2% turbidity removal of 1% kaolin suspension. In 0.1% kaolin suspension, the concentration of MoL at 10 μg/mL exhibits the highest turbidity reduction at 68 ± 1%. Thus, recombinant MoL protein from P. pastoris is an effective coagulant for water treatment.
AC Conductivity and Dielectric Properties of Borotellurite Glass
NASA Astrophysics Data System (ADS)
Taha, T. A.; Azab, A. A.
2016-10-01
Borotellurite glasses with formula 60B2O3-10ZnO-(30 - x)NaF- xTeO2 ( x = 0 mol.%, 5 mol.%, 10 mol.%, and 15 mol.%) have been synthesized by thermal melting. X-ray diffraction (XRD) analysis confirmed that the glasses were amorphous. The glass density ( ρ) was determined by the Archimedes method at room temperature. The density ( ρ) and molar volume ( V m) were found to increase with increasing TeO2 content. The direct-current (DC) conductivity was measured in the temperature range from 473 K to 623 K, in which the electrical activation energy of ionic conduction increased from 0.27 eV to 0.48 eV with increasing TeO2 content from 0 mol.% to 15 mol.%. The dielectric parameters and alternating-current (AC) conductivity ( σ ac) were investigated in the frequency range from 1 kHz to 1 MHz and temperature range from 300 K to 633 K. The AC conductivity and dielectric constant decreased with increasing TeO2 content from 0 mol.% to 15 mol.%.
NASA Astrophysics Data System (ADS)
Ouma, Immaculate L. A.; Naidoo, Eliazer B.; Ofomaja, Augustine E.
2017-08-01
Magnetite nanoparticles and magnetite-pine cone nanocomposite were prepared and applied in the adsorption of hexavalent chromium from water. Pine cone powder stabilized the nanoparticles and acted as a support while simultaneously introducing functional groups which improved metal adsorption. The nanocomposite retained the nanoparticles magnetic properties while improving chromium adsorption efficiency. Adsorption of hexavalent chromium on both materials was pH and concentration dependent with the most efficient adsorption occurring at pH 2 and 75 mg/L. On both materials, chromium adsorption was spontaneous with Gibbs free energy values of -19.2 kJ mol-1 to -23.7 kJ mol-1 and -18.0 kJ mol-1 to -24.2 kJ mol-1 for nanoparticles and nanocomposite respectively between 298 K and 319 K. The changes in enthalpy and entropy were determined to be 44.4 kJ mol-1, 212.7 J K-1 mol-1 and 78.3 kJ mol-1, 323.3 J K-1 mol-1 for the prepared nanoparticles and nanocomposite respectively.
Effect of somatostatin-14 on duodenal mucosal bicarbonate secretion in guinea pigs.
Odes, H S; Muallem, R; Reimer, R; Ioffe, S; Beil, W; Schwenk, M; Sewing, K F
1995-03-01
The role of somatostatin-14 in duodenal mucosal HCO3- secretion was investigated in anesthetized, indomethacin-treated guinea pigs. Net HCO3- output from the isolated, perfused (24 mM NaHCO3 + 130 mM NaCl) proximal duodenum was measured during intravenous infusion (alone or in combination) of somatostatin-14, carbachol, vasoactive intestinal peptide (VIP), and prostaglandin E2 (PGE2). In homogenates of duodenal enterocytes, the effect of these agents on adenylate cyclase activity was studied. Basal duodenal HCO3- secretion (3.5 +/- 0.2 mumol/cm/10 min) was reduced dose dependently by somatostatin-14 (10(-11) mol/kg, 10(-9) mol/kg, and 10(-7) mol/kg). Carbachol, VIP, and PGE2 (all 10(-8) mol/kg) increased basal duodenal HCO3- secretion two- to threefold. Somatostatin-14 (10(-7) mol/kg) abolished the stimulatory effect of carbachol and VIP, but not that of PGE2. Basal adenylate cyclase activity in isolated duodenal enterocytes (9.4 +/- 1.0 pmol cAMP/mg protein/min) was unaltered by somatostatin (10(-6) mol/liter) or carbachol (10(-3) mol/liter). VIP (10(-8) mol/liter) and PGE2 (10(-7) mol/liter) increased adenylate cyclase activity two- to threefold, and these effects were unchanged by somatostatin-14 (10(-6) mol/liter). In conclusion, somatostatin-14 inhibits basal and carbachol- and VIP-stimulated duodenal HCO3- secretion, and its mechanism of action is not via inhibition of adenylate cyclase activity in duodenal enterocytes.
Gas-phase acidities of cysteine-polyalanine peptides I: A(3,4)CSH and HSCA(3,4).
Ren, Jianhua; Tan, John P; Harper, Robert T
2009-10-15
The gas-phase acidities of four cysteine-polyalanine peptides, A(3,4)CSH and HSCA(3,4), were determined using the extended Cooks kinetic method with full entropy analysis. A triple-quadrupole mass spectrometer with an electrospray interface was employed for the experimental study. The ion activation was achieved via collision-induced dissociation (CID) experiments. The deprotonation enthalpies (Delta(acid)H) of the peptides were determined to be 332.2 +/- 2.0 kcal/mol (A(3)CSH), 325.9 +/- 2.0 kcal/mol (A(4)CSH), 319.3 +/- 3.0 kcal/mol (HSCA(3)), and 319.2 +/- 4.0 kcal/mol (HSCA(4)). The deprotonation entropies (Delta(acid)S) of the peptides were estimated based on the entropy term (Delta(DeltaS)) and the deprotonation entropies of the reference acids. By using the deprotonation enthalpies and entropies, the gas-phase acidities (Delta(acid)G) of the peptides were derived: 325.0 +/- 2.0 kcal/mol (A(3)CSH), 320.2 +/- 2.0 kcal/mol (A(4)CSH), 316.3 +/- 3.0 kcal/mol (HSCA(3)), and 315.4 +/- 4.0 kcal/mol (HSCA(4)). Conformations and energetic information of the peptides were calculated through simulated annealing (Tripos), geometry optimization (AM1), and single-point energy calculations (B3LYP/6-31+G(d)), respectively. The calculated theoretical deprotonation enthalpies (Delta(acid)H) of 334.2 kcal/mol (A(3)CSH), 327.7 kcal/mol (A(4)CSH), 320.6 kcal/mol (HSCA(3)), and 318.6 kcal/mol (HSCA(4)) are in good agreement with the experimentally determined values. Both the experimental and computational studies suggest that the two N-terminal cysteine peptides, HSCA(3,4), are significantly more acidic than the corresponding C-terminal ones, A(3,4)CSH. The high acidities of the former are likely due to the helical conformational effects for which the thiolate anion may be strongly stabilized by the interaction with the helix macrodipole.
Leedman, P J; Newman, J D; Harrison, L C
1989-07-01
We studied the subunit structure of the human TSH receptor in thyroid tissue from patients with Graves' disease and multinodular goiter by TSH affinity chromatography, immunoprecipitation with Graves' immunoglobulins (Igs), and a modified technique of Western blotting. Human TSH receptor-binding activity was purified about 1,270-fold by sequential affinity chromatography on wheat germ lectin-agarose and TSH-agarose. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of nonreduced affinity-purified receptors eluted in sodium dodecyl sulfate sample buffer revealed three noncovalently linked subunits of 70,000, 50,000, and 35,000 mol wt. When reduced, a major subunit of 25,000 mol wt was identified. When 3 mol/L NaCl was used to elute affinity-purified receptors only the 50,000 mol wt nonreduced subunit was detected. This subunit bound [125I]bovine TSH and was precipitated by Graves' Igs. Modifications to the conventional Western blotting technique enabled thyroglobulin components (approximately 220,000 mol wt), thyroid microsomal antigen (a doublet of approximately 110,000 mol wt), and putative TSH receptor subunits of 70,000 and 50,000 mol wt to be identified in thyroid particulate membranes by Graves' Igs. Blotting of affinity-purified receptors eluted in sodium dodecyl sulfate sample buffer revealed subunits of either 70,000 or 50,000 mol wt, with a minority of Graves' serum samples. We conclude that the nonreduced human TSH receptor is an oligomeric complex comprising three different subunits of 70,000, 50,000, and 35,000 mol wt. The reduced receptor exists as a single subunit of 25,000 mol wt, which may be disulfide linked to form the higher mol wt forms. The 70,000 and 50,000 mol wt subunits contain epitopes that bind Graves' Igs in modified Western blots, thus directly confirming that the human TSH receptor is a target for Graves' Igs.
NASA Astrophysics Data System (ADS)
Pommier, Matthieu; Clerbaux, Cathy; Coheur, Pierre-Francois
2017-09-01
Formic acid (HCOOH) concentrations are often underestimated by models, and its chemistry is highly uncertain. HCOOH is, however, among the most abundant atmospheric volatile organic compounds, and it is potentially responsible for rain acidity in remote areas. HCOOH data from the Infrared Atmospheric Sounding Interferometer (IASI) are analyzed from 2008 to 2014 to estimate enhancement ratios from biomass burning emissions over seven regions. Fire-affected HCOOH and CO total columns are defined by combining total columns from IASI, geographic location of the fires from Moderate Resolution Imaging Spectroradiometer (MODIS), and the surface wind speed field from the European Centre for Medium-Range Weather Forecasts (ECMWF). Robust correlations are found between these fire-affected HCOOH and CO total columns over the selected biomass burning regions, allowing the calculation of enhancement ratios equal to 7.30 × 10-3 ± 0.08 × 10-3 mol mol-1 over Amazonia (AMA), 11.10 × 10-3 ± 1.37 × 10-3 mol mol-1 over Australia (AUS), 6.80 × 10-3 ± 0.44 × 10-3 mol mol-1 over India (IND), 5.80 × 10-3 ± 0.15 × 10-3 mol mol-1 over Southeast Asia (SEA), 4.00 × 10-3 ± 0.19 × 10-3 mol mol-1 over northern Africa (NAF), 5.00 × 10-3 ± 0.13 × 10-3 mol mol-1 over southern Africa (SAF), and 4.40 × 10-3 ± 0.09 × 10-3 mol mol-1 over Siberia (SIB), in a fair agreement with previous studies. In comparison with referenced emission ratios, it is also shown that the selected agricultural burning plumes captured by IASI over India and Southeast Asia correspond to recent plumes where the chemistry or the sink does not occur. An additional classification of the enhancement ratios by type of fuel burned is also provided, showing a diverse origin of the plumes sampled by IASI, especially over Amazonia and Siberia. The variability in the enhancement ratios by biome over the different regions show that the levels of HCOOH and CO do not only depend on the fuel types.
Barik, Sudhakar; Brulla, W. J.; Bryant, M. P.
1985-01-01
Methanogenic enrichments catabolizing 13 mM phenylacetate or 4 mM phenol were established at 37°C, using a 10% inoculum from a municipal anaerobic digester. By using agar roll tubes of the basal medium plus 0.1% yeast extract-25 mM fumarate, a hydrogenotrophic lawn of Wolinella succinogenes and phenol or phenylacetate, strains P-2 and PA-1, respectively, were isolated in coculture with W. succinogenes. With the lawn deleted, PA-1 was isolated in pure culture. Strain P-2 is apparently a new species of anaerobic, motile, gram-negative, spindle-shaped, small rod that as yet has been grown only in coculture with W. succinogenes. It used phenol, hydrocinnamate, benzoate, and phenylacetate as energy sources. Product recovery by the coculture, per mole of phenol and 4.4 mol of fumarate used, included 2.03, 0.12, 0.08, and 3.23 mol, respectively, of acetate, propionate, butyrate, and succinate. Carbon recovery was 75% and H recovery was 80%, although CO2 and a few other possible products were not determined. That P-2 is an obligate proton-reducing acetogen and possible pathways for its degradation of phenol are discussed. Strain PA-1 is apparently a new species of anaerobic, motile, relatively small, gram-negative rod. It utilized compounds such as phenylacetate, hydrocinnamate, benzoate, phenol, resorcinol, gallate, 4-aminophenol, 2-aminobenzoate, pyruvate, Casamino Acids, and aspartate as energy sources in coculture with W. succinogenes. Per mole of phenylacetate and 1.44 mol of fumarate used, 1.04, 0.53, and 0.78 mol of acetate, propionate, and succinate, respectively, were recovered from the coculture. Only about 50% of the carbon and H were recovered. In coculture with Methanospirillum hungatei, 0.96 mol of acetate and 0.25 mol of methane were recovered per mol of pyruvate used; 0.90 mol of acetate and 0.33 mol of methane, per mol of fumarate used; 0.93 mol of acetate and 0.54 mol of methane, per mol of aspartate used; and 1.71 mol of acetate and 0.57 mol of methane, per mol of glucose used. Carbon and H recoveries, assuming CO2 and ammonia were produced in stoichiometric amounts, were 97 and 98% for pyruvate, 72.5 and 82% for fumarate, 96.5 and 98% for aspartate, and 61.8 and 76% for glucose. No explanation such as contamination could be found for the fact that the coculture PA-1 plus Wolinella sp. did not use glucose; after growth with M. hungatei on pyruvate, however, the latter coculture used glucose. The PA-1 pure culture produced 0.86 mol of propionate per mol of succinate used during growth. PA-1 produced a small amount of H2. Strain PA-1 is the most versatile anaerobic bacterium yet known that catabolizes monobenzenoids in the absence of electron acceptors such as sulfate or nitrate. PMID:16346852
USDA-ARS?s Scientific Manuscript database
Materials and Methods The simulation exercise and model improvement were implemented in phase-wise. In the first modelling activities, the model sensitivities were evaluated to given CO2 concentrations varying from 360 to 720 'mol mol-1 at an interval of 90 'mol mol-1 and air temperature increments...
Bohman-Frieze-Wormald model on the lattice, yielding a discontinuous percolation transition
NASA Astrophysics Data System (ADS)
Schrenk, K. J.; Felder, A.; Deflorin, S.; Araújo, N. A. M.; D'Souza, R. M.; Herrmann, H. J.
2012-03-01
The BFW model introduced by Bohman, Frieze, and Wormald [Random Struct. Algorithms1042-983210.1002/rsa.20038, 25, 432 (2004)], and recently investigated in the framework of discontinuous percolation by Chen and D'Souza [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.106.115701 106, 115701 (2011)], is studied on the square and simple-cubic lattices. In two and three dimensions, we find numerical evidence for a strongly discontinuous transition. In two dimensions, the clusters at the threshold are compact with a fractal surface of fractal dimension df=1.49±0.02. On the simple-cubic lattice, distinct jumps in the size of the largest cluster are observed. We proceed to analyze the tree-like version of the model, where only merging bonds are sampled, for dimension two to seven. The transition is again discontinuous in any considered dimension. Finally, the dependence of the cluster-size distribution at the threshold on the spatial dimension is also investigated.
NASA Astrophysics Data System (ADS)
Zhang, He; Yang, Jinglei
2014-06-01
Part I of this study (H Zhang and J Yang 2014 Smart Mater. Struct. 23 065003) reported the preparation and characterization of epoxy microcapsules (EP-capsules) and amine loaded hollow glass bubbles (AM-HGBs), and the modeling of a two-part self-healing system. In part II, the self-healing performance of this material system is systematically investigated. Various factors including the ratio, the total concentration and the size of the two carriers are studied as well as the healing temperature and the post heat treatment process. The best healing performance is obtained at a ratio of 1:3 of EP-capsules to AM-HGBs. It is observed that a higher concentration of larger carriers, together with a higher healing temperature, enables better healing behavior. Healing efficiency of up to 93% is obtained in these systems. In addition, post heat treatment decreases the healing efficiency due to stoichiometric mismatch of healing agents caused by leakage of amine in the HGBs at elevated temperature.
Plaga, W; Vielhaber, G; Wallach, J; Knappe, J
2000-01-21
The recently determined crystal structure of pyruvate formate-lyase (PFL) suggested a new view of the mechanism of this glycyl radical enzyme, namely that intermediary thiyl radicals of Cys-418 and Cys-419 participate in different ways [Becker, A. et al. (1999) Nat. Struct. Biol. 6, 969-975]. We report here a suicide reaction of PFL that occurs with the substrate-analog methacrylate with retention of the protein radical (K(I)=0.42 mM, k(i)=0.14 min(-1)). Using [1-(14)C]methacrylate (synthesized via acetone cyanhydrin), the reaction end-product was identified by peptide mapping and cocrystallization experiments as S-(2-carboxy-(2S)-propyl) substituted Cys-418. The stereoselectivity of the observed Michael addition reaction is compatible with a radical mechanism that involves Cys-418 thiyl as nucleophile and Cys-419 as H-atom donor, thus supporting the functional assignments of these catalytic amino acid residues derived from the protein structure.
Engineering Ascorbate Peroxidase Activity Into Cytochrome C Peroxidase
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meharenna, Y.T.; Oertel, P.; Bhaskar, B.
2009-05-26
Cytochrome c peroxidase (CCP) and ascorbate peroxidase (APX) have very similar structures, and yet neither CCP nor APX exhibits each others activities with respect to reducing substrates. APX has a unique substrate binding site near the heme propionates where ascorbate H-bonds with a surface Arg and one heme propionate (Sharp et al. (2003) Nat. Struct. Biol. 10, 303--307). The corresponding region in CCP has a much longer surface loop, and the critical Arg residue that is required for ascorbate binding in APX is Asn in CCP. In order to convert CCP into an APX, the ascorbate-binding loop and critical argininemore » were engineered into CCP to give the CCP2APX mutant. The mutant crystal structure shows that the engineered site is nearly identical to that found in APX. While wild-type CCP shows no APX activity, CCP2APX catalyzes the peroxidation of ascorbate at a rate of {approx}12 min{sup -1}, indicating that the engineered ascorbate-binding loop can bind ascorbate.« less
Endocytosis of lysosomal acid phosphatase; involvement of mannose receptor and effect of lectins.
Imai, K; Yoshimura, T
1994-08-01
Acid phosphatase and beta-glucosidase are unique among lysosomal enzymes in that they have both high mannose and complex type sugasr chains, whereas oligosaccharide chains of lysosomal enzymes in matrix are of high mannose type. We have previously shown that beta-glucosidase was endocytosed into macrophages via an unidentified receptor different from a mannose/fucose receptor (K. Imai, Cell Struct. Funct. 13, 325-332, 1988). Here, we show that uptake of acid phosphatase purified from rat liver lysosomes into rat macrophages was inhibited by ligands for a mannose/fucose receptor and was mediated via an apparently single binding site with Kuptake of 24.7 nM. These results indicate that acid phosphatase and beta-glucosidase recognize different types of receptors even if they have similar sugar chains. Polyvalent concanavalin A which binds both to the enzyme and to macrophages specifically stimulated the uptake in a dose dependent manner, whereas wheat germ agglutinin and phytohaemagglutinin did not.
Jaafar, Hawa Z. E.; Karimi, Ehsan; Ghasemzadeh, Ali
2014-01-01
A split plot 3 by 4 experiment was designed to investigate and distinguish the relationships among production of secondary metabolites, soluble sugar, phenylalanine ammonia lyase (PAL; EC 4.3.1.5) activity, leaf gas exchange, chlorophyll content, antioxidant activity (DPPH), and lipid peroxidation under three levels of CO2 (400, 800, and 1200 μmol/mol) and four levels of light intensity (225, 500, 625, and 900 μmol/m2/s) over 15 weeks in Labisia pumila. The production of plant secondary metabolites, sugar, chlorophyll content, antioxidant activity, and malondialdehyde content was influenced by the interactions between CO2 and irradiance. The highest accumulation of secondary metabolites, sugar, maliondialdehyde, and DPPH activity was observed under CO2 at 1200 μmol/mol + light intensity at 225 μmol/m2/s. Meanwhile, at 400 μmol/mol CO2 + 900 μmol/m2/s light intensity the production of chlorophyll and maliondialdehyde content was the highest. As CO2 levels increased from 400 to 1200 μmol/mol the photosynthesis, stomatal conductance, f v/f m (maximum efficiency of photosystem II), and PAL activity were enhanced. The production of secondary metabolites displayed a significant negative relationship with maliondialdehyde indicating lowered oxidative stress under high CO2 and low irradiance improved the production of plant secondary metabolites that simultaneously enhanced the antioxidant activity (DPPH), thus improving the medicinal value of Labisia pumila under this condition. PMID:24683336
Study on separation of minor actinides from HLLW with new extractant of TODGA-DHOA/Kerosene
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Guo-an; Zhu, Wen-bin; Li, Feng-feng
2013-07-01
The extraction behavior of U, Np, Pu, Am, rare earth elements and Sr from nitric acid solutions by TODGA/dodecan, DHOA/dodecane and TODGA-DHOA/dodecane were investigated, respectively. Based on experimental results, a separation process was proposed for minor actinide isolation from high level liquid waste (HLLW): the TODGA-DHOA/kerosene system. The multi-stage counter-current cascade experiments were carried out for the purpose by 0.1 mol/l TODGA-1.0 mol/l DHOA/kerosene with miniature mixer- settler contactor rigs (8 stages for extraction, 6 stages for scrubbing, 8 stages for first stripping, 8 stages for second stripping). The results show that the recovery efficiencies of the actinides and lanthanidesmore » are more than 99.9%, whereas less than 1% Sr was extracted by 0.1 mol/l TODGA - 1.0 mol/l DHOA/kerosene. The stripping efficiencies of U, Np and Pu are more than 95% in the first stripping step by 0.5 mol/l HNO{sub 3} + 0.5 mol/l AHA(aceto-hydroxamic acid), all of the remained actinides and lanthanides can be stripped by 0.01 mol/l HNO{sub 3} in the second stripping step. 99% Sr was extracted by 0.1 mol/l TODGA/kerosene, so Sr can be recovered efficiently directly from the raffinate by 0.1 mol/l TODGA/kerosene. (authors)« less
Sawardekar, Swapna B; Patel, Tejal C; Uchil, Dinesh
2016-01-01
The objective was to compare antiplatelet effect of lycopene with aspirin and to study effect of combination of the two on platelet aggregation in vitro, using platelets from healthy volunteers. Platelets were harvested; platelet count of platelet-rich plasma adjusted to 2.5 Χ 10(5)/μL. Aspirin (140 μmol/L) and lycopene (4, 6, 8, 10, and 12 μmol/L) were studied in vitro against adenosine-5'- diphosphate (ADP) (2.5 μM/L) and collagen. All the concentrations of lycopene (4-12 μmol/L) exhibited reduction in maximum platelet aggregation induced by aggregating agents ADP and collagen (P < 0.01 vs. vehicle) and were comparable with aspirin. Lycopene at concentration 10 μmol/L showed maximum platelet inhibition (47.05% ± 19.56%) against ADP, whereas lycopene at concentration 8 μmol/L showed maximum platelet inhibition (54.26% ± 30.71%) against collagen. Four μmol/L of lycopene combined with 140 μmol/L and 70 μmol/L aspirin showed greater inhibition of platelets as compared to aspirin 140 μmol/L alone, against both ADP and collagen. The study favorably compares lycopene and aspirin with respect to their antiplatelet activities against ADP and collagen. Lycopene can be considered as a potential target for modifying the thrombotic and pro-inflammatory events associated with platelet activation.
EFFECTS OF ELEVATED CO2 AND N-FERTILIZATION ON SURVIVAL OF PONDEROSA PINE FINE ROOTS
We used minihizaotrons to assess the effects of elevated CO2N and season on the life-span of ponderosa pine (Pinus ponderosa Dougl. Ex Laws.) fine roots. CO2 levels were ambient air (A), ambient air + 175 ?mol mol-1 (A+175) and ambient air + 350 ?mol mol-1 (A+350). N treatments ...
The Thermodynamic Conjugation Stabilization of 1,3-Butadiyne Is Zero
ERIC Educational Resources Information Center
Rogers, Donald W.; Zavitsas, Andreas A.; Matsunaga, Nikita
2010-01-01
Many textbooks point out that the thermodynamic stabilization enthalpy of 1 mol of 1,3-butadiene relative to 2 mol of 1-butene or to 1 mol of 1,4-pentadiene is slightly less than 4 kcal mol[superscript -1], owing to conjugation between the double bonds in the 1,3 configuration. It is reasonable to suppose that the analogous thermochemical…
3-(2,3-Dioxoindolin-1-yl)propanenitrile
Qachchachi, Fatima-Zahrae; Kandri Rodi, Youssef; Essassi, El Mokhtar; Bodensteiner, Michael; El Ammari, Lahcen
2014-01-01
The asymmetric unit of the title compound, C11H8N2O2, contains two independent molecules (A and B). Each molecule is build up from fused five- and six-membered rings with the former linked to a cyanoethyl group. The indoline ring and two carbonyl O atoms of each molecule are nearly coplanar, with the largest deviations from the mean planes being 0.0198 (9) (molecule A) and 0.0902 (9) Å (molecule B), each by a carbonyl O atom. The fused ring system is nearly perpendicular to the mean plane passing through the cyanoethyl chains, as indicated by the dihedral angles between them of 69.72 (9) (molecule A) and 69.15 (9)° (molecule B). In the crystal, molecules are linked by C—H⋯O and π–π [intercentroid distance between inversion-related indoline (A) rings = 3.6804 (7) Å] interactions into a double layer that stacks along the a-axis direction. PMID:24765047
NASA Technical Reports Server (NTRS)
Choi, Sung R.; Bansal, Narottam P.
2003-01-01
Various electrolyte materials for solid oxide fuel cells were fabricated by hot pressing 10 mol% yttria-stabilized zirconia (10-YSZ) reinforced with two different forms of alumina particulates and platelets each containing 0 to 30 mol% alumina. Flexure strength and fracture toughness of platelet composites were determined as a function of alumina content at 1000 C in air and compared with those of particulate composites determined previously. In general, elevated-temperature strength and fracture toughness of both composite systems increased with increasing alumina content. For a given alumina content, flexure strength of particulate composites was greater than that of platelet composites at higher alumina contents (greater than or equal to 20 mol%), whereas, fracture toughness was greater in platelet composites than in particulate composites, regardless of alumina content. The results of slow crack growth (SCG) testing, determined at 1000 C via dynamic fatigue testing for three different composites including 0 mol% (10-YSZ matrix), 30 mol % particulate and 30 mol% platelet composites, showed that susceptibility to SCG was greatest with SCG parameter n = 6 to 8 for both 0 and 30 mol% particulate composites and was least with n = 33 for the 30 mol% platelet composite.
Mazubert, Alex; Taylor, Cameron; Aubin, Joelle; Poux, Martine
2014-06-01
Microwave effects have been quantified, comparing activation energies and pre-exponential factors to those obtained in a conventionally-heated reactor for biodiesel production from waste cooking oils via transesterification and esterification reactions. Several publications report an enhancement of biodiesel production using microwaves, however recent reviews highlight poor temperature measurements in microwave reactors give misleading reaction performances. Operating conditions have therefore been carefully chosen to investigate non-thermal microwave effects alone. Temperature is monitored by an optical fiber sensor, which is more accurate than infrared sensors. For the transesterification reaction, the activation energy is 37.1kJ/mol (20.1-54.2kJ/mol) in the microwave-heated reactor compared with 31.6kJ/mol (14.6-48.7kJ/mol) in the conventionally-heated reactor. For the esterification reaction, the activation energy is 45.4kJ/mol (31.8-58.9kJ/mol) for the microwave-heated reactor compared with 56.1kJ/mol (55.7-56.4kJ/mol) for conventionally-heated reactor. The results confirm the absence of non-thermal microwave effects for homogenous-catalyzed reactions. Copyright © 2014 Elsevier Ltd. All rights reserved.
Production of hydrogen, ethanol and volatile fatty acids from the seaweed carbohydrate mannitol.
Xia, Ao; Jacob, Amita; Herrmann, Christiane; Tabassum, Muhammad Rizwan; Murphy, Jerry D
2015-10-01
Fermentative hydrogen from seaweed is a potential biofuel of the future. Mannitol, which is a typical carbohydrate component of seaweed, was used as a substrate for hydrogen fermentation. The theoretical specific hydrogen yield (SHY) of mannitol was calculated as 5 mol H2/mol mannitol (615.4 mL H2/g mannitol) for acetic acid pathway, 3 mol H2/mol mannitol (369.2 mL H2/g mannitol) for butyric acid pathway and 1 mol H2/mol mannitol (123.1 mL H2/g mannitol) for lactic acid and ethanol pathways. An optimal SHY of 1.82 mol H2/mol mannitol (224.2 mL H2/g mannitol) was obtained by heat pre-treated anaerobic digestion sludge under an initial pH of 8.0, NH4Cl concentration of 25 mM, NaCl concentration of 50mM and mannitol concentration of 10 g/L. The overall energy conversion efficiency achieved was 96.1%. The energy was contained in the end products, hydrogen (17.2%), butyric acid (38.3%) and ethanol (34.2%). Copyright © 2015 Elsevier Ltd. All rights reserved.
A Novel Nanosecond Pulsed Power Unit for the Formation of ·OH in Water
NASA Astrophysics Data System (ADS)
Li, Shengli; Hu, Sheng; Zhang, Han
2012-04-01
A novel nanosecond pulsed power unit was developed for plasma treatment of wastewater, based on the theory of magnetic pulse compression and semiconductor opening switch (SOS). The peak value, rise time and pulse duration of the output voltage were observed to be -51 kV, 60 ns and 120 ns, respectively. The concentrations of ·OH generated by the novel nanosecond pulsed plasma power were determined using the method of high-performance liquid chromatography (HPLC). The results showed that the concentrations of ·OH increased with the increase in peak voltage, and the generation rates of ·OH were 4.1 × 10-10 mol/s, 5.7 × 10-10 mol/s, and 7.7 × 10-10 mol/s at 30 kV, 35 kV, and 40 kV, respectively. The efficiency of OH generation was found to be independent of the input parameters for applied power, with an average value of 3.23×10-12 mol/J obtained.
Ośmiałowski, Borys; Valkonen, Arto; Chęcińska, Lilianna
2013-10-05
The asymmetric unit of the title compound, C14H22N4O2·0.25C6H14·0.5H2O, contains two independent mol-ecules of 2,4-bis-(pivaloyl-amino)-pyrimidine (M) with similar conformations, one water mol-ecule and one-half n-hexane solvent mol-ecule situated on an inversion center. In one independent M mol-ecule, one of the two tert-butyl groups is rotationally disordered between two orientations in a 3:2 ratio. The n-hexane solvent mol-ecule is disordered between two conformations in the same ratio. The water mol-ecule bridges two independent M mol-ecules via O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds into a 2M·H2O unit, and these units are further linked by N-H⋯N hydrogen bonds into chains running in the [010] direction. Weak C-H⋯O inter-actions are observed between the adjacent chains.
2,11-Dibromo-5,8-dibutyl[4]helicene
Isobe, Hiroyuki; Matsuno, Taisuke; Hitosugi, Shunpei; Nakanishi, Waka
2012-01-01
A racemic mixture of the title compound, C26H26Br2, a brominated [4]helicene, crystallizes, forming columns of stacked molecules. There are two crystallographically unique molecules in the asymmetric unit, both with the same helical handedness. As is typical with helicene congeners, the unique molecules show short interatomic contacts between H atoms at the fjord region, with H⋯H distances of 1.87 and 1.94 Å. Molecules with the same helical handedness segregate in the crystal packing, forming homochiral columns. The stacked molecules are piled in a column with alternate orientations. The shortest C⋯C distance in the stacked molecules is 3.306 (4) Å. PMID:22606172
Chandra, Suman; Lata, Hemant; Khan, Ikhlas A; Elsohly, Mahmoud A
2008-10-01
Effect of different photosynthetic photon flux densities (0, 500, 1000, 1500 and 2000 μmol m(-2)s(-1)), temperatures (20, 25, 30, 35 and 40 °C) and CO2 concentrations (250, 350, 450, 550, 650 and 750 μmol mol(-1)) on gas and water vapour exchange characteristics of Cannabis sativa L. were studied to determine the suitable and efficient environmental conditions for its indoor mass cultivation for pharmaceutical uses. The rate of photosynthesis (PN) and water use efficiency (WUE) of Cannabis sativa increased with photosynthetic photon flux densities (PPFD) at the lower temperatures (20-25 °C). At 30 °C, PN and WUE increased only up to 1500 μmol m(-2)s(-1) PPFD and decreased at higher light levels. The maximum rate of photosynthesis (PN max) was observed at 30 °C and under 1500 μmol m(-2)s(-1) PPFD. The rate of transpiration (E) responded positively to increased PPFD and temperature up to the highest levels tested (2000 μmol m(-2)s(-1) and 40 °C). Similar to E, leaf stomatal conductance (gs) also increased with PPFD irrespective of temperature. However, gs increased with temperature up to 30 °C only. Temperature above 30 °C had an adverse effect on gs in this species. Overall, high temperature and high PPFD showed an adverse effect on PN and WUE. A continuous decrease in intercellular CO2 concentration (Ci) and therefore, in the ratio of intercellular CO2 to ambient CO2 concentration (Ci/Ca) was observed with the increase in temperature and PPFD. However, the decrease was less pronounced at light intensities above 1500 μmol m(-2)s(-1). In view of these results, temperature and light optima for photosynthesis was concluded to be at 25-30 °C and ∼1500 μmol m(-2)s(-1) respectively. Furthermore, plants were also exposed to different concentrations of CO2 (250, 350, 450, 550, 650 and 750 μmol mol(-1)) under optimum PPFD and temperature conditions to assess their photosynthetic response. Rate of photosynthesis, WUE and Ci decreased by 50 %, 53 % and 10 % respectively, and Ci/Ca, E and gs increased by 25 %, 7 % and 3 % respectively when measurements were made at 250 μmol mol-1 as compared to ambient CO2 (350 μmol mol(-1)) level. Elevated CO2 concentration (750 μmol mol(-1)) suppressed E and gs ∼ 29% and 42% respectively, and stimulated PN, WUE and Ci by 50 %, 111 % and 115 % respectively as compared to ambient CO2 concentration. The study reveals that this species can be efficiently cultivated in the range of 25 to 30 °C and ∼1500 μmol m(-2)s(-1) PPFD. Furthermore, higher PN, WUE and nearly constant Ci/Ca ratio under elevated CO2 concentrations in C. sativa, reflects its potential for better survival, growth and productivity in drier and CO2 rich environment.
NASA Astrophysics Data System (ADS)
Wang, Huan; Liang, Xiaoping; Liu, Kai; Zhou, Qianqian; Chen, Peng; Wang, Jun; Li, Jianxin
2016-03-01
Dy3+ doped SrAl2O4:Eu2+ phosphors were synthesized by high temperature solid phase method in a weak reducing atmosphere (5% H2 + 95% N2). The relationship between the crushed granularity and the phosphors brightness was studied. The effect of co-doping amount of Dy3+, Tb3+ and Si4+ on the structure and properties of SrAl2O4:Eu2+ via response surface method was investigated. Photoluminescence measurement results showed that the initial afterglow brightness of 0.002 mol% Dy3+ doped SrAl2O4:Eu2+0.002 phosphors decreased after first increased within the sintering temperature range from 1150 to 1400 °C, which created the highest value of 12,101 mcd/m2 at 1300 °C. Numerous coarse particles in the powder ought to be crushed for the practical application, however, the brightness became lower accompanied by the decrease of the granularity. The luminescence property of SrAl2O4:Eu2+ sintered at 1200 °C improved by co-doping Dy3+-Tb3+-Si4+. The results of response surface method showed that the influence extent on the luminescence property was Dy3+ > Tb3+ > Si4+. When the co-doping amount in SrAl2O4:Eu2+0.002 phosphors of Dy3+, Tb3+ and Si4+ was 0.001 mol%, 0.0005 mol% and 0.002 mol%, respectively, the initial afterglow brightness of SrAl2O4 was up to the highest value of 12,231 mcd/m2, which was in good agreement on the predicted maximum value of 12,519 mcd/m2 with the optimum co-doping amount of 0.0015 mol% Dy3+, 0.0005 mol% Tb3+ and 0.0017 mol% Si4+. The brightness of co-doped phosphors not only increased by 56.79% than that of SrAl2O4:Eu2+0.002, Dy3+0.002 sintered at 1200 °C, but also was above that of 1300 °C. The emission spectra results showed that, compared with 0.001 mol% Dy3+ doped phosphor, the emission peak of 0.001 mol% Dy3+-0.001 mol% Tb3+ co-doped phosphor generated red shift and increased by 9.3% in emission intensity; 0.001 mol% Dy3+-0.004 mol% Si4+ and 0.001 mol% Dy3+-0.001 mol% Tb3+-0.004 mol% Si4+ co-doped SrAl2O4:Eu2+0.002 emission peak created blue shift and increased by 37.2% and 47.6% in emission intensity, respectively.
2014-08-20
including zero-point energy ( ZPE ) corrections, 43.21 kcal/mol and 50.46 kcal/mol, respectively. The decomposition initiated by trans-HONO elimination can...CCSD(T)/cc-pVTZ level with ZPE corrections) of 47.00 kcal/mol and 48.27 kcal/mol, respectively. Thus, at the CCSD(T)/cc-pVTZ level, the ordering of
We conducted a 4-year study of Pinus ponderosa fine root (<2 mm) responses to atmospheric CO2 and N-fertilization. Seedlings were grown in open-top chambers at 3 CO2 levels (ambient, ambient+175 mol/mol, ambient+350 mol/mol) and 3 N-fertilization levels (0, 10, 20 g?m-2?yr-1). ...
A novel Ru/TiO2 hybrid nanocomposite catalyzed photoreduction of CO2 to methanol under visible light
NASA Astrophysics Data System (ADS)
Kumar, Pawan; Joshi, Chetan; Labhsetwar, Nitin; Boukherroub, Rabah; Jain, Suman L.
2015-09-01
A novel in situ synthesized Ru(bpy)3/TiO2 hybrid nanocomposite is developed for the photoreduction of CO2 into methanol under visible light irradiation. The prepared composite was characterized by means of SEM, TEM, XRD, DT-TGA, XPS, UV-Vis and FT-IR techniques. The photocatalytic activity of the synthesized hybrid catalyst was tested for the photoreduction of CO2 under visible light using triethylamine as a sacrificial donor. The methanol yield for the Ru(bpy)3/TiO2 hybrid nanocomposite was found to be 1876 μmol g-1 cat (φMeOH 0.024 mol Einstein-1) that was much higher in comparison with the in situ synthesized TiO2, 828 μmol g-1 cat (φMeOH 0.010 mol Einstein-1) and the homogeneous Ru(bpy)3Cl2 complex, 385 μmol g-1 cat (φMeOH 0.005 mol Einstein-1).A novel in situ synthesized Ru(bpy)3/TiO2 hybrid nanocomposite is developed for the photoreduction of CO2 into methanol under visible light irradiation. The prepared composite was characterized by means of SEM, TEM, XRD, DT-TGA, XPS, UV-Vis and FT-IR techniques. The photocatalytic activity of the synthesized hybrid catalyst was tested for the photoreduction of CO2 under visible light using triethylamine as a sacrificial donor. The methanol yield for the Ru(bpy)3/TiO2 hybrid nanocomposite was found to be 1876 μmol g-1 cat (φMeOH 0.024 mol Einstein-1) that was much higher in comparison with the in situ synthesized TiO2, 828 μmol g-1 cat (φMeOH 0.010 mol Einstein-1) and the homogeneous Ru(bpy)3Cl2 complex, 385 μmol g-1 cat (φMeOH 0.005 mol Einstein-1). Electronic supplementary information (ESI) available: GC chromatograms of reaction products and calibration curve for methanol analysis. See DOI: 10.1039/c5nr03712c
Elshahed, M S; McInerney, M J
2001-12-01
The anaerobic bacterium Syntrophus aciditrophicus metabolized benzoate in pure culture in the absence of hydrogen-utilizing partners or terminal electron acceptors. The pure culture of S. aciditrophicus produced approximately 0.5 mol of cyclohexane carboxylate and 1.5 mol of acetate per mol of benzoate, while a coculture of S. aciditrophicus with the hydrogen-using methanogen Methanospirillum hungatei produced 3 mol of acetate and 0.75 mol of methane per mol of benzoate. The growth yield of the S. aciditrophicus pure culture was 6.9 g (dry weight) per mol of benzoate metabolized, whereas the growth yield of the S. aciditrophicus-M. hungatei coculture was 11.8 g (dry weight) per mol of benzoate. Cyclohexane carboxylate was metabolized by S. aciditrophicus only in a coculture with a hydrogen user and was not metabolized by S. aciditrophicus pure cultures. Cyclohex-1-ene carboxylate was incompletely degraded by S. aciditrophicus pure cultures until a free energy change (DeltaG') of -9.2 kJ/mol was reached (-4.7 kJ/mol for the hydrogen-producing reaction). Cyclohex-1-ene carboxylate, pimelate, and glutarate transiently accumulated at micromolar levels during growth of an S. aciditrophicus pure culture with benzoate. High hydrogen (10.1 kPa) and acetate (60 mM) levels inhibited benzoate metabolism by S. aciditrophicus pure cultures. These results suggest that benzoate fermentation by S. aciditrophicus in the absence of hydrogen users proceeds via a dismutation reaction in which the reducing equivalents produced during oxidation of one benzoate molecule to acetate and carbon dioxide are used to reduce another benzoate molecule to cyclohexane carboxylate, which is not metabolized further. Benzoate fermentation to acetate, CO(2), and cyclohexane carboxylate is thermodynamically favorable and can proceed at free energy values more positive than -20 kJ/mol, the postulated minimum free energy value for substrate metabolism.
NASA Astrophysics Data System (ADS)
Wang, Dongmei; Wang, Weiwei; Xu, Nianjun; Sun, Xue
2016-12-01
Many species of microalga Dunaliella exhibit a remarkable tolerance to salinity and are therefore ideal for probing the effects of salinity. In this work, we assessed the effects of NaCl stress on the growth, activity and mRNA level of carbon and nitrogen metabolism enzymes of D. viridis. The alga could grow over a salinity range of 0.44 mol L-1 to 3.00 mol L-1 NaCl, but the most rapid growth was observed at 1.00 mol L-1 NaCl, followed by 2.00 mol L-1 NaCl. Paralleling these growth patterns, the highest initial and total Rubisco activities were detected in the presence of 1.00 mol L-1 NaCl, decreasing to 37.33% and 26.39% of those values, respectively, in the presence of 3.00 mol L-1 NaCl, respectively. However, the highest extracellular carbonic anhydrase (CA) activity was measured in the presence of 2.00 mol L-1 NaCl, followed by 1.00 mol L-1 NaCl. Different from the two carbon enzymes, nitrate reductase (NR) activity showed a slight change under different NaCl concentrations. At the transcriptional level, the mRNAs of Rubisco large subunit ( rbcL), and small subunit ( rbcS), attained their highest abundances in the presence of 1.00 and 2.00 mol L-1 NaCl, respectively. The CA mRNA accumulation was induced from 0.44 mol L-1 to 3.00 mol L-1 NaCl, but the NR mRNA showed the decreasing tendency with the increasing salinity. In conclusion, the growth and carbon fixation enzyme of Rubisco displayed similar tendency in response to NaCl stress, CA was proved be salt-inducible within a certain salinity range and NR showed the least effect by NaCl in D. viridis.
Elshahed, Mostafa S.; McInerney, Michael J.
2001-01-01
The anaerobic bacterium Syntrophus aciditrophicus metabolized benzoate in pure culture in the absence of hydrogen-utilizing partners or terminal electron acceptors. The pure culture of S. aciditrophicus produced approximately 0.5 mol of cyclohexane carboxylate and 1.5 mol of acetate per mol of benzoate, while a coculture of S. aciditrophicus with the hydrogen-using methanogen Methanospirillum hungatei produced 3 mol of acetate and 0.75 mol of methane per mol of benzoate. The growth yield of the S. aciditrophicus pure culture was 6.9 g (dry weight) per mol of benzoate metabolized, whereas the growth yield of the S. aciditrophicus-M. hungatei coculture was 11.8 g (dry weight) per mol of benzoate. Cyclohexane carboxylate was metabolized by S. aciditrophicus only in a coculture with a hydrogen user and was not metabolized by S. aciditrophicus pure cultures. Cyclohex-1-ene carboxylate was incompletely degraded by S. aciditrophicus pure cultures until a free energy change (ΔG′) of −9.2 kJ/mol was reached (−4.7 kJ/mol for the hydrogen-producing reaction). Cyclohex-1-ene carboxylate, pimelate, and glutarate transiently accumulated at micromolar levels during growth of an S. aciditrophicus pure culture with benzoate. High hydrogen (10.1 kPa) and acetate (60 mM) levels inhibited benzoate metabolism by S. aciditrophicus pure cultures. These results suggest that benzoate fermentation by S. aciditrophicus in the absence of hydrogen users proceeds via a dismutation reaction in which the reducing equivalents produced during oxidation of one benzoate molecule to acetate and carbon dioxide are used to reduce another benzoate molecule to cyclohexane carboxylate, which is not metabolized further. Benzoate fermentation to acetate, CO2, and cyclohexane carboxylate is thermodynamically favorable and can proceed at free energy values more positive than −20 kJ/mol, the postulated minimum free energy value for substrate metabolism. PMID:11722901
Bustamante, S; Orensanz, L M; Barahona, M V; García-Sacristán, A; Hernández, M
2001-01-01
The current study was designed to characterize the functionally active tachykinin receptors involved in tachykinin-elicited contractions in the pig intravesical ureter, and to investigate the possible modulation exerted by the natural tachykinins substance P (SP) and neurokinin A (NKA) on the non-adrenergic non-cholinergic (NANC) excitatory ureteral neurotransmission. In pig intravesical ureteral strips pretreated with phosphoramidon (10(-5) mol/L) to block the endopeptidase activities, isometric force recordings showed that SP, NKA, and the NK2 receptor selective agonist [beta-Ala(8)]-NKA (4-10), all three induced contractions, with the following potency order: NKA > [beta-Ala(8) ]-NKA (4-10) > SP. [Sar(9), Met(O(2))(11)]-SP and senktide, selective agonists of the NK1 and NK3 receptors, respectively, failed to modify the ureteral tone. Urothelium removal and incubation with tetrodotoxin (10(-6) mol/L), phentolamine (10(-7) mol/L), propranolol (3 x 10(-6) mol/L), atropine (10(-7) mol/L) and indomethacin (3 x 10(-6) mol/L), did not alter the contraction induced by a submaximal (10(-7) mol/L) dose of [beta-Ala(8)]-NKA (4-10). MEN 10,376 (10(-8)-10(-7) mol/L), a NK2 receptor antagonist, reduced the contraction to 3 x 10(-8) mol/L NKA. GR 82334 (10(-6) -10(-5) mol/L) and SR 142801 (10(-8)-10(-7) mol/L), selective antagonists of the NK1 and NK3 receptors, respectively, did not modify that contraction. In pig intravesical ureteral strips in NANC conditions, SP and NKA induced a potentiation of the contractions to electrical field stimulation (EFS) and to exogenous ATP. The results suggest that the tachykinins evoke a direct contraction of pig intravesical ureteral strips through NK2 receptors located in the smooth muscle. SP and NKA exert an enhancement of the NANC excitatory neurotransmission of the pig intravesical ureter.
Decrease of serum carnitine levels in patients with or without gastrointestinal cancer cachexia
Malaguarnera, Mariano; Risino, Corrado; Gargante, Maria Pia; Oreste, Giovanni; Barone, Gloria; Tomasello, Anna Veronica; Costanzo, Mario; Cannizzaro, Matteo Angelo
2006-01-01
AIM: To evaluate the levels of serum carnitine in patients with cancer in digestive organs and to compare them with other cancers in order to provide new insights into the mechanisms of cachexia. METHODS: Fifty-five cachectic patients with or without gastrointestinal cancer were enrolled in the present study. They underwent routine laboratory investigations, including examination of the levels of various forms of carnitine present in serum (i.e., long-chain acylcarnitine, short-chain acylcarnitine, free carnitine, and total carnitine). These values were compared with those found in 60 cancer patients in good nutritional status as well as with those of 30 healthy control subjects. RESULTS: When the cachectic patients with gastro-intestinal cancer were compared with the cachectic patients without gastrointestinal cancer, the difference was -6.8 μmol/L in free carnitine (P < 0.005), 0.04 μmol/L in long chain acylcarnitine (P < 0.05), 8.7 μmol/L in total carnitine (P < 0.001). In the cachectic patients with or without gastrointestinal cancer, the difference was 12.2 μmol/L in free carnitine (P < 0.001), 4.60 μmol/L in short chain acylcarnitine (P < 0.001), and 0.60 μmol /L in long-chain acylcarnitine (P < 0.005) and 17.4 μmol/L in total carnitine (P < 0.001). In the cachectic patients with gastrointestinal cancer and the healthy control subjects, the difference was 15.5 μmol/L in free carnitine (P < 0.001), 5.2 μmol /L in short-chain acylcarnitine (P < 0.001), 1.0 μmol/L in long chain acylcarnitine (P < 0.001), and 21.8 μmol/L in total carnitine (P < 0.001). CONCLUSION: Low serum levels of carnitine in terminal neoplastic patients are decreased greatly due to the decreased dietary intake and impaired endogenous synthesis of this substance. These low serum carnitine levels also contribute to the progression of cachexia in cancer patients. PMID:16874868
The challenges of numerically simulating analogue brittle thrust wedges
NASA Astrophysics Data System (ADS)
Buiter, Susanne; Ellis, Susan
2017-04-01
Fold-and-thrust belts and accretionary wedges form when sedimentary and crustal rocks are compressed into thrusts and folds in the foreland of an orogen or at a subduction trench. For over a century, analogue models have been used to investigate the deformation characteristics of such brittle wedges. These models predict wedge shapes that agree with analytical critical taper theory and internal deformation structures that well resemble natural observations. In a series of comparison experiments for thrust wedges, called the GeoMod2004 (1,2) and GeoMod2008 (3,4) experiments, it was shown that different numerical solution methods successfully reproduce sandbox thrust wedges. However, the GeoMod2008 benchmark also pointed to the difficulties of representing frictional boundary conditions and sharp velocity discontinuities with continuum numerical methods, in addition to the well-known challenges of numerical plasticity. Here we show how details in the numerical implementation of boundary conditions can substantially impact numerical wedge deformation. We consider experiment 1 of the GeoMod2008 brittle thrust wedge benchmarks. This experiment examines a triangular thrust wedge in the stable field of critical taper theory that should remain stable, that is, without internal deformation, when sliding over a basal frictional surface. The thrust wedge is translated by lateral displacement of a rigid mobile wall. The corner between the mobile wall and the subsurface is a velocity discontinuity. Using our finite-element code SULEC, we show how different approaches to implementing boundary friction (boundary layer or contact elements) and the velocity discontinuity (various smoothing schemes) can cause the wedge to indeed translate in a stable manner or to undergo internal deformation (which is a fail). We recommend that numerical studies of sandbox setups not only report the details of their implementation of boundary conditions, but also document the modelling attempts that failed. References 1. Buiter and the GeoMod2004 Team, 2006. The numerical sandbox: comparison of model results for a shortening and an extension experiment. Geol. Soc. Lond. Spec. Publ. 253, 29-64 2. Schreurs and the GeoMod2004 Team, 2006. Analogue benchmarks of shortening and extension experiments. Geol. Soc. Lond. Spec. Publ. 253, 1-27 3. Buiter, Schreurs and the GeoMod2008 Team, 2016. Benchmarking numerical models of brittle thrust wedges, J. Struct. Geol. 92, 140-177 4. Schreurs, Buiter and the GeoMod2008 Team, 2016. Benchmarking analogue models of brittle thrust wedges, J. Struct. Geol. 92, 116-13
Myosin dephosphorylation during rapid relaxation of hog carotid artery smooth muscle.
Driska, S P; Stein, P G; Porter, R
1989-02-01
Changes in myosin light chain phosphorylation were measured during histamine-induced rhythmic contractions of hog carotid artery smooth muscle strips. Histamine made the muscle strips contract spontaneously every 1-5 min, and this allowed measurement of the time course of phosphorylation in relation to force development under conditions where diffusion of the agonist through tissue would not complicate the interpretation of the data. In the absence of histamine, phosphorylation was low [0.12 +/- 0.04 mol P/mol of the 20,000-Da light chain (LC 20)]. Phosphorylation was slightly (but not significantly) higher in the presence of 10 microM histamine in the relaxed state between contractions (0.20 +/- 0.03 mol P/mol LC 20). In muscle strips frozen during force development, when force had reached half of its peak value, phosphorylation was 0.38 +/- 0.06 mol P/mol LC 20. The highest levels of phosphorylation (0.49 +/- 0.04 mol P/mol LC 20) were found in strips frozen at the peak of the rhythmic contractions. Strips frozen when force had declined to half of the peak force showed low levels of phosphorylation (0.17 +/- 0.07 mol P/mol LC 20), indicating that the myosin light chain phosphatase activity was quite high. Mathematical modeling of the kinase and phosphatase reactions suggested that the apparent first-order phosphatase rate constant was at least 0.08 s-1 under these conditions. To obtain a better estimate of this rate constant, a second series of phosphorylation measurements were made early in the relaxation phase of the rhythmic contractions. The highest phosphatase rate constant obtained from these measurements was 0.23 s-1.(ABSTRACT TRUNCATED AT 250 WORDS)
Cieplik, Jerzy; Pluta, Janusz; Bryndal, Iwona; Lis, Tadeusz
2013-11-27
The title compound, C26H23F3N4O, crystallizes with two symmetry-independent mol-ecules in the asymmetric unit, denoted A and B, which differ mainly in the rotation of the meth-oxy-phenyl ring. The -CF3 group of mol-ecule B is disordered by rotation, with the F atoms split over two sets of sites; the occupancy factor for the major component is 0.853 (4). The dihedral angles between the pyrimidine ring and the attached phenyl, meth-oxy-phenyl and tri-fluoro-methyl-phenyl rings are 8.1 (2), 37.5 (2) and 70.7 (2)°, respectively, in mol-ecule A, and 9.3 (2), 5.3 (2) and 79.7 (2)° in mol-ecule B. An intra-molecular N-H⋯N hydrogen bond occurs in each mol-ecule. In the crystal, two crystallographically independent mol-ecules associate into a dimer via a pair of N-H⋯N hydrogen bonds, with a resulting R 2 (2)(12) ring motif and π-π stacking inter-actions [centroid-centroid distance = 3.517 (4) Å] between the pyrimidine rings. For the A mol-ecules, there are inter-molecular C-H⋯O hydrogen bonds between an aryl C atom of meth-oxy-phenyl ring and a meth-oxy O atom of an adjacent mol-ecule. A similar inter-action is lacking in the B mol-ecules.
Sawardekar, Swapna B.; Patel, Tejal C.; Uchil, Dinesh
2016-01-01
Introduction: The objective was to compare antiplatelet effect of lycopene with aspirin and to study effect of combination of the two on platelet aggregation in vitro, using platelets from healthy volunteers. Materials and Methods: Platelets were harvested; platelet count of platelet-rich plasma adjusted to 2.5 Χ 105/μL. Aspirin (140 μmol/L) and lycopene (4, 6, 8, 10, and 12 μmol/L) were studied in vitro against adenosine-5’- diphosphate (ADP) (2.5 μM/L) and collagen Results: All the concentrations of lycopene (4–12 μmol/L) exhibited reduction in maximum platelet aggregation induced by aggregating agents ADP and collagen (P < 0.01 vs. vehicle) and were comparable with aspirin. Lycopene at concentration 10 μmol/L showed maximum platelet inhibition (47.05% ± 19.56%) against ADP, whereas lycopene at concentration 8 μmol/L showed maximum platelet inhibition (54.26% ± 30.71%) against collagen. Four μmol/L of lycopene combined with 140 μmol/L and 70 μmol/L aspirin showed greater inhibition of platelets as compared to aspirin 140 μmol/L alone, against both ADP and collagen. Conclusion: The study favorably compares lycopene and aspirin with respect to their antiplatelet activities against ADP and collagen. Lycopene can be considered as a potential target for modifying the thrombotic and pro-inflammatory events associated with platelet activation. PMID:26997718
Basic studies on the pyrolysis of lignin compounds
Byung-ho Hwang
2003-01-01
By pyrolyzing lignin model compounds 1-lV at 315°C, an investigation was carried out with some results. In the pyrolysis of lignin model compound I and 11, 0.47 mol of guaiacol, 0.57 mol of dimethoxyphenol (DMP), and 0.12 and 0.23 mol of dimethoxyaceton ophenone (DMAP) were produced respectively. In the pyrolysis of lignin model compound lll and lV, 0.26 mol of...
Stabilized aqueous hydrogen peroxide solution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malin, M.J.; Sciafani, L.D.
1988-05-17
This patent describes a stabilized aqueous hydrogen peroxide solution having a pH below 7 and an amount of Ferric ion up to about 2 ppm comprising hydrogen peroxide, acetanilide having a concentration which ranges between 0.74 M Mol/L and 2.22 mMol/L, and o-benzene disulfonic acid or salt thereof at a concentration between about 0.86 mMol/L to about 1.62 mMol/L.
Crystal structure of bis-(N-methyl-N-phenyl-amino)-tris-ulfane.
Barany, George; Henley, Matthew J; Polski, Lauren A; Schroll, Alayne L; Young, Victor G
2015-07-01
The title compound, C14H16N2S3, crystallized with two independent mol-ecules [(1 a ) and (1 b )] in the asymmetric unit. Both mol-ecules display a pseudo-trans conformation. The two consecutive S-S bond lengths of the tris-ulfane unit of mol-ecule (1 a ) are 2.06 (3) and 2.08 (3) Å, and 2.08 (3) and 2.07 (2) Å for mol-ecule (1 b ). Torsion angles about each of the two S-S bonds are 86.6 (2) and 87.0 (2)° for (1 a ), and -84.6 (2) and -85.9 (2)° for (1 b ). The core atoms, viz. the N-S-S-S-N moiety, of the two mol-ecules superimpose well if one is inverted on the other, but the phenyl groups do not. Thus, the two units are essentially conformational enanti-omers. In mol-ecule (1 a ), the two phenyl rings are inclined to one another by 86.7 (3)°, and in mol-ecule (1 b ), by 81.1 (3)°. In the crystal, mol-ecules are linked via C-H⋯π inter-actions, forming sheets lying parallel to (010).
Role of carbonic anhydrase in basal and stimulated bicarbonate secretion by the guinea pig duodenum.
Muallem, R; Reimer, R; Odes, H S; Schwenk, M; Beil, W; Sewing, K F
1994-05-01
The role of carbonic anhydrase in the process of proximal duodenal mucosal bicarbonate secretion was investigated in the guinea pig. In a series of experiments in vivo, the duodenum was perfused with 24 mmol/liter NaHCO3 solution (+ NaCl for isotonicity) to ensure that active duodenal HCO3- secretion against a concentration gradient was measured. Acetazolamide (80 mg/kg) was infused intravenously to examine the role of carbonic anhydrase on basal and agonist-stimulated HCO3- secretion. Acetazolamide abolished basal HCO3- secretion and significantly decreased HCO3- secretion after stimulation with dibutyryl 5'-cyclic adenosine monophosphate (dBcAMP, 10(-5) mol/kg), dibutyryl 5'-cyclic guanosine monophosphate (dBcGMP, 10(-5) mol/kg), prostaglandin E2 (PGE2, 10(-6) mol/kg), PGF2 alpha (10(-6) mol/kg), tetradecanoyl-phorbol-acetate (TPA, 10(-7) mol/kg), glucagon (10(-7) mol/kg), vasoactive intestinal polypeptide (VIP, 10(-8) mol/kg), and carbachol (10(-8) mol/kg). Utilizing a fluorescence technique, we could detect the enzyme carbonic anhydrase in equal amounts in villous and crypt cells of the proximal duodenal epithelium; no activity was demonstrated in tissues pretreated with acetazolamide. In conclusion, carbonic anhydrase is required for both basal and stimulated duodenal HCO3- secretion.
Hydrogen-bonding patterns in 5-fluoro-cytosine-melamine co-crystal (4/1).
Mohana, Marimuthu; Muthiah, Packianathan Thomas; Sanjeewa, Liurukara D; McMillen, Colin D
2016-04-01
The asymmetric unit of the title compound, 4C4H4FN3O·C3H6N6, comprises of two independent 5-fluoro-cytosine (5FC) mol-ecules (A and B) and one half-mol-ecule of melamine (M). The other half of the melamine mol-ecule is generated by a twofold axis. 5FC mol-ecules A and B are linked through two different homosynthons [R 2 (2)(8) ring motif]; one is formed via a pair of N-H⋯O hydrogen bonds and the second via a pair of N-H⋯N hydrogen bonds. In addition to this pairing, the O atoms of 5FC mol-ecules A and B inter-act with the N2 amino group on both sides of the melamine mol-ecule, forming a DDAA array of quadruple hydrogen bonds and generating a supra-molecular pattern. The 5FC (mol-ecules A and B) and two melamine mol-ecules inter-act via N-H⋯O, N-H⋯N and N-H⋯O, N-H⋯N, C-H⋯F hydrogen bonds forming R 6 (6)(24) and R 4 (4)(15) ring motifs. The crystal structure is further strengthened by C-H⋯F, C-F⋯π and π-π stacking inter-actions.
Microstructure and Properties of KSr2Nb5O15 Ceramics with Excess K+
NASA Astrophysics Data System (ADS)
Wang, Min; Gao, Feng; Xu, Jie; Zhang, Chaochao; Qin, Mengjie; Wang, Li; Guo, Yiting
2017-03-01
KSr2Nb5O15- xK (KSN- xK, x = 0 mol.%, 4 mol.%, 8 mol.%, 12 mol.%, 16 mol.%, and 20 mol.%) lead-free ferroelectric ceramics have been prepared by a buried sintering method using needle-like KSN particles synthesized by molten salt synthesis, and their microstructure, dielectric properties, and infrared transmittance investigated. The results suggest that the KSN- xK ceramics had simplex tungsten bronze structure for x ≤ 12 mol.%, but K2Nb8O21 secondary phase appeared at higher x. Excess K+ compensated the shortage of A-site ions in KSN crystallites, alleviated lattice distortion, and drove the KSN component closer to stoichiometric ratio, all of which increased the Curie temperature. The dielectric relaxor behavior of the ceramics was enhanced as the excess K+ content was increased. The dielectric constant, dielectric tunability, and infrared transmittance initially increased then decreased with increasing x. The specimen with 12 mol.% excess K+ showed optimum electrical properties, including maximum infrared transmittance of ˜60%. This work confirms that A-site vacancies in KSN can be compensated by excess K+, and that this effect can be used to adjust the local composition, alleviate structural distortion of the oxygen octahedron, enhance the Curie temperature, etc.
NASA Astrophysics Data System (ADS)
Phillips-Lander, Charity M.; Parnell, S. R.; McGraw, L. E.; Elwood Madden, M. E.
2018-06-01
A diverse suite of carbonate minerals including calcite (CaCO3) and magnesite (MgCO3) have been observed on the martian surface and in meteorites. Terrestrial carbonates usually form via aqueous processes and often record information about the environment in which they formed, including chemical and textural biosignatures. In addition, terrestrial carbonates are often found in association with evaporite deposits on Earth. Similar high salinity environments and processes were likely active on Mars and some areas may contain active high salinity brines today. In this study, we directly compare calcite and magnesite dissolution in ultrapure water, dilute sulfate and chloride solutions, as well as near-saturated sulfate and chloride brines with known activity of water (aH2O) to determine how dissolution rates vary with mineralogy and aH2O, as well as aqueous cation and anion chemistry to better understand how high salinity fluids may have altered carbonate deposits on Mars. We measured both calcite and magnesite initial dissolution rates at 298 K and near neutral pH (6-8) in unbuffered solutions containing ultrapure water (18 MΩ cm-1 UPW; aH2O = 1), dilute (0.1 mol kg-1; aH2O = 1) and near-saturated Na2SO4 (2.5 mol kg-1, aH2O = 0.92), dilute (0.1 mol kg-1, aH2O = 1) and near-saturated NaCl (5.7 mol kg-1, aH2O = 0.75). Calcite dissolution rates were also measured in dilute and near-saturated MgSO4 (0.1 mol kg-1, aH2O = 1 and 2.7 mol kg-1, aH2O = 0.92, respectively) and MgCl2 (0.1 mol kg-1, aH2O = 1 and 3 mol kg-1, aH2O = 0.73, respectively), while magnesite dissolution rates were measured in dilute and near-saturated CaCl2 (0.1 mol kg-1, aH2O = 1 and 9 mol kg-1, aH2O = 0.35). Initial calcite dissolution rates were fastest in near-saturated MgCl2 brine, while magnesite dissolution rates were fastest in dilute (0.1 mol kg-1) NaCl and CaCl2 solutions. Calcite dissolution rates in near-saturated Na2SO4 were similar to those observed in the dilute solutions (-8.00 ± 0.12 log mol m-2 s-1), while dissolution slowed in both NaCl solutions (0.1 mol kg-1; -8.23 ± 0.10 log mol m-2 s-1 and (5.7 mol kg-1; -8.44 ± 0.11 log mol m-2 s-1), as well as near-saturated MgSO4 brine (2.7 mol kg-1; -8.35 ± 0.05 log mol m-2 s-1). The slowest calcite dissolution rates observed in the near-saturated NaCl brine. Magnesite dissolution rates were ∼5 times faster in the dilute salt solutions relative to UPW, but similar to UPW (-8.47 ± 0.06 log mol m-2 s-1) in near-saturated Na2SO4 brines (-8.41 ± 0.18 log mol m-2 s-1). Magnesite dissolution slowed significantly in near-saturated CaCl2 brine (-9.78 ± 0.10 log mol m-2 s-1), likely due to the significantly lower water activity in these experiments. Overall, magnesite dissolution rates are slower than calcite dissolution rates and follow the trend: All dilute salt solutions >2.5 mol kg-1 Na2SO4 ≈ UPW > 5.7 mol kg-1 NaCl >> 9 mol kg-1 CaCl2. Calcite rates follow the trend 3 mol kg-1 MgCl2 > 2.5 mol kg-1 Na2SO4 ≈ UPW ≈ all dilute salt solutions >2.7 mol kg-1 MgSO4 ≈ 5.7 mol kg-1 NaCl. Magnesite dissolution rates in salt solutions generally decrease with decreasing aH2O in both chloride and sulfate brines, which indicates water molecules act as ligands and participate in the rate-limiting magnesite dissolution step. However, there is no general trend associated with water activity observed in the calcite dissolution rates. Calcite dissolution accelerates in near-saturated MgCl2, but slows in near-saturated NaCl brine despite both brines having similar water activities (aH2O = 0.73 and 0.75, respectively). High Mg calcite was observed as a reaction product in the near-saturated MgCl2, indicating Mg2+ from solution likely substituted for Ca2+ in the initial calcite, releasing additional Ca2+ into solution and increasing the observed calcite dissolution rate. Calcite dissolution rates also increase slightly as Na2SO4 concentration increases, while calcite dissolution rates slow slightly with increasing concentration of MgSO4 and NaCl. However, all of the carbonate rates vary by less than 0.5 log units and are within or near the standard deviation observed for each set of replicate experiments. Carbonate mineral lifetimes in high salinity brines indicate magnesite may be preferentially preserved compared to calcite on Mars. Therefore, Mg-carbonates that have experienced post-depositional aqueous alteration are more likely to preserve paleoenvironmental indicators and potential biosignatures. Rapid weathering of carbonates in circum-neutral pH sulfate brines may provide a potential source of cations for abundant sulfate minerals observed on Mars, Ceres, and other planetary bodies.
Low-melting point heat transfer fluid
Cordaro, Joseph G [Oakland, CA; Bradshaw, Robert W [Livermore, CA
2011-04-12
A low-melting point, heat transfer fluid comprising a mixture of LiNO.sub.3, NaNO.sub.3, KNO.sub.3, NaNO.sub.2 and KNO.sub.2 salts where the Li, Na and K cations are present in amounts of about 20-33.5 mol % Li, about 18.6-40 mol % Na, and about 40-50.3 mol % K and where the nitrate and nitrite anions are present in amounts of about 36-50 mol % NO.sub.3, and about 50-62.5 mol % NO.sub.2. These compositions can have liquidus temperatures between 70.degree. C. and 80.degree. C. for some compositions.
NASA Astrophysics Data System (ADS)
Cremer, Dieter; Kraka, Elfi; Crehuet, Ramon; Anglada, Josep; Gräfenstein, Jürgen
2001-10-01
The ozone-acetylene reaction is found to proceed via an intermediate van der Waals complex (rather than a biradical), which is the precursor for a concerted symmetry-allowed [4+2] cycloaddition reaction leading to 1,2,3-trioxolene. CCSD(T)/6-311G+(2d, 2p) and CCSD(T)/CBS (complete basis set) calculations predict the ozone-acetylene van der Waals complex to be stable by 2.2 kcal mol -1, the calculated activation enthalpy for the cycloaddition reaction is 9.6 kcal mol -1 and the reaction enthalpy -55.5 kcal mol -1. Calculated kinetic data for the overall reaction ( k=0.8 l mol -1 s-1, A=1.71×10 6 l mol -1 s-1, E a=8.6 kcal mol -1) suggest that there is a need for refined kinetic measurements.
NASA Astrophysics Data System (ADS)
Vinogradov, An V.; Voszka, R.; Kovalev, Valerii I.; Faĭzullov, F. S.; Janszky, J.
1987-06-01
A significant increase (by a factor of about 3) of the bulk damage threshold in the case of interaction of CO2 laser radiation pulses with ultrapure NaCl and KCl crystals grown in a reactive atmosphere was observed on introduction of divalent metal ions Ca and Pb in concentrations of 10-5-10-6 mol/mol. Impurities were introduced in concentrations of 10-8-10-3 and 2×10-7-10-4 mol/mol into the melts of KCl and NaCl, respectively. The concentration of other impurities (including OH) did not exceed ~10-6 mol/mol. A physical model was developed to account for the observed dependence on the basis of an analogy between a system of colloidal particles and F centers in a crystal and a liquid-vapor system.
HackaMol: An Object-Oriented Modern Perl Library for Molecular Hacking on Multiple Scales
Riccardi, Demian M.; Parks, Jerry M.; Johs, Alexander; ...
2015-03-20
HackaMol is an open source, object-oriented toolkit written in Modern Perl that organizes atoms within molecules and provides chemically intuitive attributes and methods. The library consists of two components: HackaMol, the core that contains classes for storing and manipulating molecular information, and HackaMol::X, the extensions that use the core. We tested the core; it is well-documented and easy to install across computational platforms. Our goal for the extensions is to provide a more flexible space for researchers to develop and share new methods. In this application note, we provide a description of the core classes and two extensions: HackaMol::X::Calculator, anmore » abstract calculator that uses code references to generalize interfaces with external programs, and HackaMol::X::Vina, a structured class that provides an interface with the AutoDock Vina docking program.« less
HackaMol: An Object-Oriented Modern Perl Library for Molecular Hacking on Multiple Scales.
Riccardi, Demian; Parks, Jerry M; Johs, Alexander; Smith, Jeremy C
2015-04-27
HackaMol is an open source, object-oriented toolkit written in Modern Perl that organizes atoms within molecules and provides chemically intuitive attributes and methods. The library consists of two components: HackaMol, the core that contains classes for storing and manipulating molecular information, and HackaMol::X, the extensions that use the core. The core is well-tested, well-documented, and easy to install across computational platforms. The goal of the extensions is to provide a more flexible space for researchers to develop and share new methods. In this application note, we provide a description of the core classes and two extensions: HackaMol::X::Calculator, an abstract calculator that uses code references to generalize interfaces with external programs, and HackaMol::X::Vina, a structured class that provides an interface with the AutoDock Vina docking program.
HackaMol: An Object-Oriented Modern Perl Library for Molecular Hacking on Multiple Scales
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riccardi, Demian M.; Parks, Jerry M.; Johs, Alexander
HackaMol is an open source, object-oriented toolkit written in Modern Perl that organizes atoms within molecules and provides chemically intuitive attributes and methods. The library consists of two components: HackaMol, the core that contains classes for storing and manipulating molecular information, and HackaMol::X, the extensions that use the core. We tested the core; it is well-documented and easy to install across computational platforms. Our goal for the extensions is to provide a more flexible space for researchers to develop and share new methods. In this application note, we provide a description of the core classes and two extensions: HackaMol::X::Calculator, anmore » abstract calculator that uses code references to generalize interfaces with external programs, and HackaMol::X::Vina, a structured class that provides an interface with the AutoDock Vina docking program.« less
NASA Astrophysics Data System (ADS)
Mullabaev, Albert; Tkacheva, Olga; Shishkin, Vladimir; Kovrov, Vadim; Zaikov, Yuriy; Sukhanov, Leonid; Mochalov, Yuriy
2018-03-01
Crystallization temperatures (liquidus and solidus) in the LiCl-Li2O and (LiCl-KCl)-Li2O systems with the KCl content of 10 and 20 mol.% were obtained with independent methods of thermal analysis using cooling curves, isothermal saturation, and differential scanning calorimetry. The linear sweep voltammetry was applied to control the time of the equilibrium establishment in the molten system after the Li2O addition, which depended on the composition of the base melt and the concentration of Li2O. The fragments of the binary LiCl-Li2O and quazi-binary [LiCl-KCl(10 mol.%)]-Li2O and [LiCl-KCl(20 mol.%)]-Li2O phase diagrams in the Li2O concentration range from 0 to 12 mol.% were obtained. The KCl presence in the LiCl-KCl-Li2O molten mixture in the amount of 10 and 20 mol.% reduces the liquidus temperature by 30 and 80°, respectively, but the region of the homogeneous molten state of the system is considerably narrowed, which complicates its practical application. The Li2O solubility in the molten LiCl, LiCl-KCl(10 mol.%) and LiCl-KCl(20 mol.%) decreases with increasing the KCl content and is equal to 11.5, 7.7 and 3.9 mol.% at 650°С, respectively. The LiCl-KCl melt with 10 mol.% KCl can be recommended for practical use as a medium for the SNF pyro-chemical reprocessing at temperature below 700 °C.
Bile Acids Increase Independently From Hypocaloric Restriction After Bariatric Surgery.
Jahansouz, Cyrus; Xu, Hongliang; Hertzel, Ann V; Serrot, Federico J; Kvalheim, Nicholas; Cole, Abigail; Abraham, Anasooya; Luthra, Girish; Ewing, Kristin; Leslie, Daniel B; Bernlohr, David A; Ikramuddin, Sayeed
2016-12-01
To measure changes in the composition of serum bile acids (BA) and the expression of Takeda G-protein-coupled receptor 5 (TGR5) acutely after bariatric surgery or caloric restriction. Metabolic improvement after bariatric surgery occurs before substantial weight loss. BA are important metabolic regulators acting through the farnesoid X receptor and TGR5 receptor. The acute effects of surgery on BA and the TGR5 receptor in subcutaneous white adipose tissue (WAT) are unknown. A total of 27 obese patients with type 2 diabetes mellitus were randomized to Roux-en-Y gastric bypass (RYGB) or to hypocaloric diet (HC diet) restriction (NCT 1882036). A cohort of obese patients with and without type 2 diabetes mellitus undergoing vertical sleeve gastrectomy was also recruited (n = 12) as a comparison. After vertical sleeve gastrectomy, the level of BA increased [total: 1.17 ± 1.56 μmol/L to 4.42 ± 3.92 μmol/L (P = 0.005); conjugated BA levels increased from 0.99 ± 1.42 μmol/L to 3.59 ± 3.70 μmol/L (P = 0.01) and unconjugated BA levels increased from 0.18 ± 0.24 μmol/L to 0.83 ± 0.70 μmol/L (P = 0.009)]. With RYGB, there was a trend toward increased BA [total: 1.37 ± 0.97 μmol/L to 3.26 ± 3.01 μmol/L (P = 0.07); conjugated: 1.06 ± 0.81 μmol/L to 2.99 ± 3.02 μmol/L (P = 0.06)]. After HC diet, the level of unconjugated BA decreased [0.92 ± 0.55 μmol/L to 0.32 ± 0.43 μmol/L (P = 0.05)]. The level of WAT TGR5 gene expression decreased after surgery, but not in HC diet. Protein levels did not change. The levels of serum BA increase after bariatric surgery independently from caloric restriction, whereas the level of WAT TGR5 protein is unaffected.
NASA Astrophysics Data System (ADS)
Durig, J. R.; Phan, H. V.; Little, T. S.
1989-09-01
The Raman (3200-10 cm -1) and IR (3200-30 cm -1) spectra of bromoacetyl fluoride, bromoacetyl chloride and bromoacetyl bromide in the gaseous and annealed solid phases have been recorded. Additionally, the Raman spectra and the qualitative depolarization measurements for each molecule in the liquid phase have been obtained. All of these data indicate that these bromoacetyl halides exist in mixtures of two conformers, with the trans rotamer (halogen atoms oriented trans to one another) being the thermodynamically preferred, and the gauche conformation being the high energy form. From the studies of Raman spectra at different temperatures, the enthalpy differences have been determined for the gaseous and liquid phases, respectively, to be 185 ± 23 cm -1 (0.53 ± 0.06 kcal mol -1) and 249 ± 27 cm -1 (0.71 ± 0.08 kcal mol -1) for bromoacetyl fluoride, 391 ± 130 cm -1 (1.12 ± 0.37 kcal mol -1) and 317 ± 27 cm -1 (0.91 ± 0.08 kcal mol -1) for bromoacetyl chloride, and 341 ± 48 cm -1 (0.98 ± 0.14 kcal mol -1) and 286 ± 26 cm -1 (0.82 ± 0.07 kcal mol -1) for bromoacetyl bromide. Potential functions have been calculated for the fluoride and chloride from the observed asymmetric torsional frequencies and values of 580 ± 11 cm -1 (1.66 ± 0.03 kcal mol -1), 359 ± 8 cm -1 (1.03 ± 0.02 kcal mol -1), and 387 ± 16 cm -1 (1.11 ± 0.04 kcal mol -1) for the trans to gauche, gauche to gauche to gauche and gauche to trans barrier, respectively, were determined for bromoacetyl fluoride. The corresponding quantities were 967 ± 30 cm -1 (2.76 ± 0.08 kcal mol -1), 696 ± 67 cm -1 (1.99 ± 0.19 kcal mol -1), and 663 ± 30 cm -1 (1.61 ± 0.08 kcal mol -1) for bromoacetyl chloride. These potential functions are consistent with the dihedral angle of the gauche conformation being 120° and 117° for the fluoride and chloride, respectively. Complete vibrational assignments have been carried out based on the observed IR band contours, the depolarization ratios, and group frequencies. The results are compared to those for other haloacetyl halides.
eMolTox: prediction of molecular toxicity with confidence.
Ji, Changge; Svensson, Fredrik; Zoufir, Azedine; Bender, Andreas
2018-03-07
In this work we present eMolTox, a web server for the prediction of potential toxicity associated with a given molecule. 174 toxicology-related in vitro/vivo experimental datasets were used for model construction and Mondrian conformal prediction was used to estimate the confidence of the resulting predictions. Toxic substructure analysis is also implemented in eMolTox. eMolTox predicts and displays a wealth of information of potential molecular toxicities for safety analysis in drug development. The eMolTox Server is freely available for use on the web at http://xundrug.cn/moltox. chicago.ji@gmail.com or ab454@cam.ac.uk. Supplementary data are available at Bioinformatics online.
Chen, Min-Hua; Yoshioka, Tomohiko; Ikoma, Toshiyuki; Hanagata, Nobutaka; Lin, Feng-Huei; Tanaka, Junzo
2014-10-01
Theranostic nanoparticles currently have been regarded as an emerging concept of 'personalized medicine' with diagnostic and therapeutic dual-functions. Eu 3+ doped hydroxyapatite (HAp) has been regarded as a promising fluorescent probe for in vivo imaging applications. Additionally, substitution of Ca 2+ with Fe 3+ in HAp crystal may endow the capability of producing heat upon exposure to a magnetic field. Here we report a preliminary study of doping mechanism and photoluminescence of Eu 3+ and Fe 3+ doped HAp nanoparticles (Eu/Fe:HAp). HAp with varied concentration of Eu 3+ and Fe 3+ doping are presented as Eu(10 mol%):HAp, Eu(7 mol%)-Fe(3 mol%):HAp, Eu(5 mol%)-Fe(5 mol%):HAp, Eu(3 mol%)-Fe(7 mol%):HAp, and Fe(10 mol%):HAp in the study. The results showed that the HAp particles, in nano-size with rod-like morphology, were successfully doped with Eu 3+ and Fe 3+ , and the particles can be well suspended in cell culture medium. Photoluminescence analysis revealed that particles have prominent emissions at 536 nm, 590 nm, 615 nm, 650 nm and 695 nm upon excitation at a wavelength of 397 nm. Moreover, these Eu/Fe:HAp nanoparticles belonged to B-type carbonated HAp, which has been considered an effective biodegradable and biocompatible drug/gene carrier in biological applications.
Crystal structure of bis(N-methyl-N-phenylamino)trisulfane
Barany, George; Henley, Matthew J.; Polski, Lauren A.; Schroll, Alayne L.; Young, Victor G.
2015-01-01
The title compound, C14H16N2S3, crystallized with two independent molecules [(1 a) and (1 b)] in the asymmetric unit. Both molecules display a pseudo-trans conformation. The two consecutive S—S bond lengths of the trisulfane unit of molecule (1 a) are 2.06 (3) and 2.08 (3) Å, and 2.08 (3) and 2.07 (2) Å for molecule (1 b). Torsion angles about each of the two S—S bonds are 86.6 (2) and 87.0 (2)° for (1 a), and −84.6 (2) and −85.9 (2)° for (1 b). The core atoms, viz. the N—S—S—S—N moiety, of the two molecules superimpose well if one is inverted on the other, but the phenyl groups do not. Thus, the two units are essentially conformational enantiomers. In molecule (1 a), the two phenyl rings are inclined to one another by 86.7 (3)°, and in molecule (1 b), by 81.1 (3)°. In the crystal, molecules are linked via C—H⋯π interactions, forming sheets lying parallel to (010). PMID:26279880
Chen, Xueye; Shen, Jienan; Li, Tiechuan
2016-01-01
A microreactor for the chemiluminescence detection of copper (II) in water samples, based on the measurement of light emitted from the copper (II) catalysed oxidation of 1,10-phenanthroline by hydrogen peroxide in basic aqueous solution, is presented. Polymethyl methacrylate (PMMA) was chose as material for fabricating the microreactor with mill and hot bonding method. Optimized reagents conditions were found to be 6.3 × 10(-5)mol/L 1,10-phenanthroline, 1.5 × 10(-3)mol/L hydrogen peroxide, 7.0 × 10(-2)mol/L sodium hydroxide and 2.4 × 10(-5)mol/L Hexadecyl trimethyl ammonium Bromide (CTMAB). In the continuous flow injection mode the system can perform fully automated detection with a reagent consumption of only 3.5 μL each time. The linear range of the Cu (II) ions concentration was 1.5 × 10(-8) mol/L to 1.0 × 10(-4) mol/L, and the detection limit was 9.4 × 10(-9)mol/L with the S/N ratio of 4. The relative standard deviation was 3.0 % for 2.0 × 10(-6) mol/L Cu (II) ions (n = 10). The most obvious features of the detection method are simplicity, rapidity and easy fabrication of the microreactor.
A novel membrane-less direct alcohol fuel cell
NASA Astrophysics Data System (ADS)
Yi, Qingfeng; Chen, Qinghua; Yang, Zheng
2015-12-01
Membrane-less fuel cell possesses such advantages as simplified design and lower cost. In this paper, a membrane-less direct alcohol fuel cell is constructed by using multi-walled carbon nanotubes (MWCNT) supported Pd and ternary PdSnNi composites as the anode catalysts and Fe/C-PANI composite, produced by direct pyrolysis of Fe-doped polyaniline precursor, as the oxygen reduction reaction (ORR) catalyst. The alcohols investigated in the present study are methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol and sec-butanol. The cathode catalyst Fe/C-PANI is electrochemically inactive to oxidation of the alcohols. The performance of the cell with various alcohols in 1 mol L-1 NaOH solution on either Pd/MWCNT or PdSnNi/MWCNT catalyst has been evaluated. In any case, the performance of the cell using the anode catalyst PdSnNi/MWCNT is considerably better than Pd/MWCNT. For the PdSnNi/MWCNT, the maximum power densities of the cell using methanol (0.5 mol L-1), ethanol (0.5 mol L-1), n-propanol (0.5 mol L-1), iso-propanol (0.5 mol L-1), n-butanol (0.2 mol L-1), iso-butanol (0.2 mol L-1) and sec-butanol (0.2 mol L-1) are 0.34, 1.03, 1.07, 0.44, 0.50, 0.31 and 0.15 mW cm-2, respectively.
Hydrogen-bonding patterns in 5-fluorocytosine–melamine co-crystal (4/1)
Mohana, Marimuthu; Muthiah, Packianathan Thomas; Sanjeewa, Liurukara D.; McMillen, Colin D.
2016-01-01
The asymmetric unit of the title compound, 4C4H4FN3O·C3H6N6, comprises of two independent 5-fluorocytosine (5FC) molecules (A and B) and one half-molecule of melamine (M). The other half of the melamine molecule is generated by a twofold axis. 5FC molecules A and B are linked through two different homosynthons [R 2 2(8) ring motif]; one is formed via a pair of N—H⋯O hydrogen bonds and the second via a pair of N—H⋯N hydrogen bonds. In addition to this pairing, the O atoms of 5FC molecules A and B interact with the N2 amino group on both sides of the melamine molecule, forming a DDAA array of quadruple hydrogen bonds and generating a supramolecular pattern. The 5FC (molecules A and B) and two melamine molecules interact via N—H⋯O, N—H⋯N and N—H⋯O, N—H⋯N, C—H⋯F hydrogen bonds forming R 6 6(24) and R 4 4(15) ring motifs. The crystal structure is further strengthened by C—H⋯F, C—F⋯π and π–π stacking interactions. PMID:27375887
Medeiros, Roberta Antigo; de Carvalho, Adriana Evaristo; Rocha-Filho, Romeu C; Fatibello-Filho, Orlando
2008-07-30
A simple and highly selective electrochemical method was developed for the simultaneous determination of aspartame and cyclamate in dietary products at a boron-doped diamond (BDD) electrode. In square-wave voltammetric (SWV) measurements, the BDD electrode was able to separate the oxidation peak potentials of aspartame and cyclamate present in binary mixtures by about 400 mV. The detection limit for aspartame in the presence of 3.0x10(-4) mol L(-1) cyclamate was 4.7x10(-7) mol L(-1), and the detection limit for cyclamate in the presence of 1.0x10(-4) mol L(-1) aspartame was 4.2x10(-6) mol L(-1). When simultaneously changing the concentration of both aspartame and cyclamate in a 0.5 mol L(-1) sulfuric acid solution, the corresponding detection limits were 3.5x10(-7) and 4.5x10(-6) mol L(-1), respectively. The relative standard deviation (R.S.D.) obtained was 1.3% for the 1.0x10(-4) mol L(-1) aspartame solution (n=5) and 1.1% for the 3.0x10(-3) mol L(-1) cyclamate solution. The proposed method was successfully applied in the determination of aspartame in several dietary products with results similar to those obtained using an HPLC method at 95% confidence level.
NASA Astrophysics Data System (ADS)
Chen, Min-Hua; Yoshioka, Tomohiko; Ikoma, Toshiyuki; Hanagata, Nobutaka; Lin, Feng-Huei; Tanaka, Junzo
2014-10-01
Theranostic nanoparticles currently have been regarded as an emerging concept of ‘personalized medicine’ with diagnostic and therapeutic dual-functions. Eu3+ doped hydroxyapatite (HAp) has been regarded as a promising fluorescent probe for in vivo imaging applications. Additionally, substitution of Ca2+ with Fe3+ in HAp crystal may endow the capability of producing heat upon exposure to a magnetic field. Here we report a preliminary study of doping mechanism and photoluminescence of Eu3+ and Fe3+ doped HAp nanoparticles (Eu/Fe:HAp). HAp with varied concentration of Eu3+ and Fe3+ doping are presented as Eu(10 mol%):HAp, Eu(7 mol%)-Fe(3 mol%):HAp, Eu(5 mol%)-Fe(5 mol%):HAp, Eu(3 mol%)-Fe(7 mol%):HAp, and Fe(10 mol%):HAp in the study. The results showed that the HAp particles, in nano-size with rod-like morphology, were successfully doped with Eu3+ and Fe3+, and the particles can be well suspended in cell culture medium. Photoluminescence analysis revealed that particles have prominent emissions at 536 nm, 590 nm, 615 nm, 650 nm and 695 nm upon excitation at a wavelength of 397 nm. Moreover, these Eu/Fe:HAp nanoparticles belonged to B-type carbonated HAp, which has been considered an effective biodegradable and biocompatible drug/gene carrier in biological applications.
Jennings, Brett L; Bell, Justin D; Hyodo, Susumu; Toop, Tes; Donald, John A
2007-07-01
This study investigated vasodilator mechanisms in the dorsal aorta of the elephant fish, Callorhinchus milii, using anatomical and physiological approaches. Nitric oxide synthase could only be located in the perivascular nerve fibres and not the endothelium of the dorsal aorta, using NADPH histochemistry and immunohistochemistry. In vitro organ bath experiments demonstrated that a NO/soluble guanylyl cyclase (GC) system appeared to be absent in the vascular smooth muscle, since the NO donors SNP (10(-4) mol l(-1)) and SIN-1 (10(-5) mol l(-1)) were without effect. Nicotine (3 x 10(-4) mol l(-1)) mediated a vasodilation that was not affected by ODQ (10(-5) mol l(-1)), L-NNA (10(-4) mol l(-1)), indomethacin (10(-5) mol l(-1)), or removal of the endothelium. In contrast, the voltage-gated sodium channel inhibitor, tetrodotoxin (10(-5) mol l(-1)), significantly decreased the dilation induced by nicotine, suggesting that it contained a neural component. Pre-incubation of the dorsal aorta with the calcitonin gene-related peptide (CGRP) receptor antagonist, CGRP(8-37) (10(-6) mol l(-1)) also caused a significant decrease in the nicotine-induced dilation. We propose that nicotine is mediating a neurally-derived vasodilation in the dorsal aorta that is independent of NO, prostaglandins and the endothelium, and partly mediated by CGRP.
Ruan, Ya Nan; Xu, Sheng; Guo, Long; Zhu, Ming Zhu; Wang, Cong; Li, Shu Yuan; Wang, Hong Yan
2017-11-01
By using the open top chambers (OTCs) fumigation method, this paper investigated the changes of foliar injury, level of reactive oxygen species (ROS), activities and gene expression of antioxidant enzymes in Ginkgo biloba leaves under different ozone (ambient ozone≈40, 80, 160, 200 nmol·mol -1 ) concentrations, in order to study the effects of elevated ozone (O 3 ) concentrations on reactive metabolism. The results showed that the obvious foliar injuries were observed in 160 and 200 nmol·mol -1 O 3 treatments, while no visible injury was observed in 80 nmol·mol -1 O 3 and ambient O 3 treatments. After 20 d, a significant increase in O 2 -· generation rate was observed in G. biloba leaves exposed to 160, 200 nmol·mol -1 O 3 , compared with ambient ozone and 80 nmol·mol -1 O 3 , and there were no significant differences between ambient O 3 and 80 nmol·mol -1 treatments. After 40 d, H 2 O 2 content of G. biloba leaves in 160 and 200 nmol·mol -1 O 3 was significantly higher than that in 80 nmol·mol -1 and ambient ozone, respectively. The activities of catalase (CAT) in 160 and 200 nmol·mol -1 treatments were also significantly higher than that in 80 nmol·mol -1 and ambient O 3 treatments. The ascorbate peroxidase (APX) activity of leaves for each elevated O 3 treatment was lower than that of ambient ozone. The level of CAT and APX expression increased progressively after 40 d O 3 treatment. The expression intensity of GbD was conspicuously strengthened along with the increase of ozone concentration and fumigation time. Le-vel of reactive oxygen increased, activities of antioxidant enzyme decreased, level of gene expression down-regulated, and foliar visible injury was observed in leaves of G. biloba in elevated ozone stress.
Hebbachi, Rabihe; Djedouani, Amel; Kadri, Soumia; Mousser, Hénia; Mousser, Abdelhamid
2015-01-01
The title Schiff base compound, C22H19NO2S, crystallized with two independent molecules (A and B) in the asymmetric unit. Both molecules have an E conformation about the C=N bond. The two molecules differ in the orientation of the aromatic rings with respect to each other. The outer 4-methoxybenzene ring is inclined to the central benzene ring and the outer 4-acetylbenzene ring by 1.80 (19) and 63.73 (19)°, respectively, in molecule A, and by 6.72 (18) and 68.53 (19)°, respectively, in molecule B. The two outer benzene rings are inclined to one another by 63.77 (18) and 63.19 (18)° in molecules A and B, respectively. In the crystal, the individual molecules stack in columns along [010], and are linked by a number of C—H⋯π interactions, forming slabs lying parallel to (001). PMID:25878856
Azam, Mohsin; Marwood, Lindsey; Ismail, Khalida; Evans, Tyrrell; Sivaprasad, Sobha; Winkley, Kirsty; Amiel, Stephanie Anne
2015-01-01
Background. WHO's recommendation of HbA1c ≥ 48 mmol/mol (6.5%) as diagnostic for type 2 diabetes mellitus (T2DM) was adopted by three UK London boroughs in May 2012. The South London Diabetes (SOUL-D) study has recruited people with newly diagnosed T2DM since 2008. We compared participants diagnosed before May 2012 with HbA1c < 48 mmol/mol to those with diagnostic HbA1c ≥ 48 mmol/mol. Methods. A prospective cohort study of newly diagnosed T2DM participants from 96 primary care practices, comparing demographic and biomedical variables between those with diagnostic HbA1c < 48 mmol/mol or HbA1c ≥ 48 mmol/mol at recruitment and after one year. Results. Of 1488 participants, 22.8% had diagnostic HbA1c < 48 mmol/mol. They were older and more likely to be white (p < 0.05). At recruitment and one year, there were no between-group differences in the prevalence of diabetic complications, except that those diagnosed with HbA1c < 48 mmol/mol had more sensory neuropathy at recruitment (p = 0.039) and, at one year, had new myocardial infarction (p = 0.012) but less microalbuminuria (p = 0.012). Conclusions. Use of HbA1c ≥ 48 mmol/mol as the sole T2DM diagnostic criterion may miss almost a quarter of those previously diagnosed in South London yet HbA1c < 48 mmol/mol may not exclude clinically important diabetes.
HA-1077 inhibits cell migration/invasion of oral squamous cell carcinoma.
Moreira Carboni, Simone de Sales Costa; Rodrigues Lima, Nathália Alves; Pinheiro, Nanci Mendes; Tavares-Murta, Beatriz Martins; Crema, Virgínia Oliveira
2015-10-01
Oral squamous cell carcinoma (OSCC) is the most malignant lesion occurring in the head and neck. The Rho-kinases (ROCKs), effectors of Rho proteins, are involved in actin cytoskeletal organization, cell migration, and maintenance cortex. The HA-1077 inhibits the ROCKs. This study aimed to evaluate the effect of treatment with HA-1077 on cell motility in SCC-4 cells, a cell line originating from human OSCC. F-actin of SCC-4 cells treated or not with HA-1077 (1, 50 and 100 μmol/l), and also HA-1077 50 μmol/l and/or inhibitors Y-27632 30 μmol/l was stained with rhodamine-conjugated phalloidin and analyzed by confocal microscopy. Approximately 1×10 cells/well, control and treated with HA-1077 (25, 50, and 100 μmol/l) were added to the migration plate assay. In addition, 1×10 cells/well, control and treated with HA-1077 50 μmol/l, were tested by invasion assays (plate coated with Matrigel). The inhibition of ROCKs with HA-1077 and/or Y-27632 leads to morphological changes, affecting the organization of the actin. The inhibitory effect of HA-1077 (P<0.0001) was dose dependent as the number of cells migrated at 100 μmol/l was statistically different: 25 μmol/l (P<0.0001) and 50 μmol/l (P<0.01). The number of cells treated with HA-1077 50 μmol/l decreased compared with control cells that invaded through Matrigel (P<0.0001). This study shows an inhibitory effect of HA-1077 on cell migration and invasion, suggesting that the use of HA-1077 can be a potential therapy for OSCC.
Azam, Mohsin; Marwood, Lindsey; Ismail, Khalida; Evans, Tyrrell; Sivaprasad, Sobha; Winkley, Kirsty; Amiel, Stephanie Anne
2015-01-01
Background. WHO's recommendation of HbA1c ≥ 48 mmol/mol (6.5%) as diagnostic for type 2 diabetes mellitus (T2DM) was adopted by three UK London boroughs in May 2012. The South London Diabetes (SOUL-D) study has recruited people with newly diagnosed T2DM since 2008. We compared participants diagnosed before May 2012 with HbA1c < 48 mmol/mol to those with diagnostic HbA1c ≥ 48 mmol/mol. Methods. A prospective cohort study of newly diagnosed T2DM participants from 96 primary care practices, comparing demographic and biomedical variables between those with diagnostic HbA1c < 48 mmol/mol or HbA1c ≥ 48 mmol/mol at recruitment and after one year. Results. Of 1488 participants, 22.8% had diagnostic HbA1c < 48 mmol/mol. They were older and more likely to be white (p < 0.05). At recruitment and one year, there were no between-group differences in the prevalence of diabetic complications, except that those diagnosed with HbA1c < 48 mmol/mol had more sensory neuropathy at recruitment (p = 0.039) and, at one year, had new myocardial infarction (p = 0.012) but less microalbuminuria (p = 0.012). Conclusions. Use of HbA1c ≥ 48 mmol/mol as the sole T2DM diagnostic criterion may miss almost a quarter of those previously diagnosed in South London yet HbA1c < 48 mmol/mol may not exclude clinically important diabetes. PMID:26090473
Crystal structure of (E)-4-hy-droxy-N'-(3-meth-oxy-benzyl-idene)benzohydrazide.
Chantrapromma, Suchada; Prachumrat, Patcharawadee; Ruanwas, Pumsak; Boonnak, Nawong; Kassim, Mohammad B
2016-09-01
The title compound, C 15 H 14 N 2 O 3 , crystallizes with two independent mol-ecules ( A and B ) in the asymmetric unit that differ in the orientation of the 3-meth-oxy-phenyl group with respect to the methyl-idenebenzohydrazide unit. The dihedral angles between the two benzene rings are 24.02 (10) and 29.30 (9)° in mol-ecules A and B , respectively. In mol-ecule A , the meth-oxy group is twisted slightly relative to its bound benzene ring, with a C meth-yl -O-C-C torsion angle of 14.2 (3)°, whereas it is almost co-planar in mol-ecule B , where the corresponding angle is -2.4 (3)°. In the crystal, the mol-ecules are linked by N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds, as well as by weak C-H⋯O inter-actions, forming sheets parallel to the bc plane. The N-H⋯O hydrogen bond and weak C-H⋯O inter-action link different mol-ecules ( A ⋯ B ) whereas both O-H⋯N and O-H⋯O hydrogen bonds link like mol-ecules ( A ⋯ A ) and ( B ⋯ B ). Pairs of inversion-related B mol-ecules are stacked approximately along the a axis by π-π inter-actions in which the distance between the centroids of the 3-meth-oxy-phenyl rings is 3.5388 (12) Å. The B mol-ecules also participate in weak C-H⋯π inter-actions between the 4-hy-droxy-phenyl and the 3-meth-oxy-phenyl rings.
Goldman, Lawrence M; Amyes, Tina L; Goryanova, Bogdana; Gerlt, John A; Richard, John P
2014-07-16
The mechanism for activation of orotidine 5'-monophosphate decarboxylase (OMPDC) by interactions of side chains from Gln215 and Try217 at a gripper loop and R235, adjacent to this loop, with the phosphodianion of OMP was probed by determining the kinetic parameters k(cat) and K(m) for all combinations of single, double, and triple Q215A, Y217F, and R235A mutations. The 12 kcal/mol intrinsic binding energy of the phosphodianion is shown to be equal to the sum of the binding energies of the side chains of R235 (6 kcal/mol), Q215 (2 kcal/mol), Y217 (2 kcal/mol), and hydrogen bonds to the G234 and R235 backbone amides (2 kcal/mol). Analysis of a triple mutant cube shows small (ca. 1 kcal/mol) interactions between phosphodianion gripper side chains, which are consistent with steric crowding of the side chains around the phosphodianion at wild-type OMPDC. These mutations result in the same change in the activation barrier to the OMPDC-catalyzed reactions of the whole substrate OMP and the substrate pieces (1-β-D-erythrofuranosyl)orotic acid (EO) and phosphite dianion. This shows that the transition states for these reactions are stabilized by similar interactions with the protein catalyst. The 12 kcal/mol intrinsic phosphodianion binding energy of OMP is divided between the 8 kcal/mol of binding energy, which is utilized to drive a thermodynamically unfavorable conformational change of the free enzyme, resulting in an increase in (k(cat))(obs) for OMPDC-catalyzed decarboxylation of OMP, and the 4 kcal/mol of binding energy, which is utilized to stabilize the Michaelis complex, resulting in a decrease in (K(m))(obs).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tirado-Lee, Leidamarie; Lee, Allen; Rees, Douglas C.
2014-10-02
molA (HI1472) from H. influenzae encodes a periplasmic binding protein (PBP) that delivers substrate to the ABC transporter MolB{sub 2}C{sub 2} (formerly HI1470/71). The structures of MolA with molybdate and tungstate in the binding pocket were solved to 1.6 and 1.7 {angstrom} resolution, respectively. The MolA-binding protein binds molybdate and tungstate, but not other oxyanions such as sulfate and phosphate, making it the first class III molybdate-binding protein structurally solved. The {approx}100 {mu}M binding affinity for tungstate and molybdate is significantly lower than observed for the class II ModA molybdate-binding proteins that have nanomolar to low micromolar affinity for molybdate.more » The presence of two molybdate loci in H. influenzae suggests multiple transport systems for one substrate, with molABC constituting a low-affinity molybdate locus.« less
Solvent effects and potential of mean force study of the SN2 reaction of CH3+CN‑ in water
NASA Astrophysics Data System (ADS)
Li, Chen; Liu, Peng; Li, Yongfang; Wang, Dunyou
2018-03-01
We used a combined quantum mechanics and molecular mechanics (QM/MM) method to investigate the solvent effects and potential of mean force of the CH3F+CN‑ reaction in water. Comparing to gas phase, the water solution substantially affects the structures of the stationary points along the reaction path. We quantitatively obtained the solvent effects’ contributions to the reaction: 1.7 kcal/mol to the activation barrier and ‑26.0 kcal/mol to the reaction free energy. The potential mean of force calculated with the density functional theory/MM theory has a barrier height at 19.7 kcal/mol, consistent with the experimental result at 23.0 kcal/mol; the calculated reaction free energy at ‑43.5 kcal/mol is also consistent with the one estimated based on the gas-phase data at ‑39.7 kcal/mol. Project supported by the National Natural Science Foundation of China (Grant No. 11774206) and Taishan Scholarship Fund from Shandong Province, China.
N-(1-Allyl-1H-indazol-5-yl)-4-meth-oxy-benzene-sulfonamide hemihydrate.
Chicha, Hakima; Rakib, El Mostapha; Geffken, Detlef; Saadi, Mohamed; El Ammari, Lahcen
2013-01-01
In the title compound, C17H17N3O3 (.)0.5H2O, the indazole system makes a dihedral angle of 46.19 (8)° with the plane through the benzene ring and is nearly perpendicular to the allyl group, as indicated by the dihedral angle of 81.2 (3)°. In the crystal, the water mol-ecule, disordered over two sites related by an inversion center, forms O-H⋯N bridges between indazole N atoms of two sulfonamide mol-ecules. It is also connected via N-H⋯O inter-action to the third sulfonamide mol-ecule; however, due to the water mol-ecule disorder, only every second mol-ecule of sulfonamide participates in this inter-action. This missing inter-action results in a slight disorder of the sulfonamide S,O and N atoms which are split over two sites with half occupancy. With the help of C-H⋯O hydrogen bonds, the mol-ecules are further connected into a three-dimensional network.
NASA Astrophysics Data System (ADS)
Wang, Zheng-Fang; Zhang, Qing; Gong, Min
1995-12-01
Laboratory culture experiments showed that <100μ mol/L nitrate, amonium or mixture of amino acids promote the growth of the red tide organism Prorocentrum micans Ehrenb, but that >100μmol/L of ammonium, or mixture of glycine and glutamate was harmful to growth, and that orthophosphate was P. micans’ main phosphorous source in the ocean. Presence of 80μ mol/L EDTA, 0.5 to 1 μmol/L Fe3+, 1.0 to 20.0 μ mol/L Mn2+ 0.1 to 0.4 μmol/L Co2+ in the culture medium could improve the growth of P. micans. Vitamin B1 promoted growth, but vitamin B12 and biotin did not. The estimated minimum cell quotas ( q o) for nitrogen and phosphorus being 0.74 pmole/cell and 0.045 pmole/cell show that phosphorus (more than nitrogen) limits the growth of P. micans in the study area.
Yang, Ke Bin; Meng, Fan Zhi; Guo, Xian Feng
2017-06-18
Aiming at the problem of the acute shortage of CO 2 in winter production of cut Anthurium andraeanum in solar greenhouse, the effect of CO 2 fertilization on photosynthetic characteristics and growth performance of A. andraeanum 'Fire' was investigated. Three treatments with different concentrations of CO 2 were designed, i.e., 700, 1000 and 1300 Μmol·mol -1 , with receiving no extra CO 2 as the control. The results showed that for the CO 2 -fertilized plants, the photosynthetic rate, intercellular CO 2 concentration and water use efficiency were significantly greater than those in the control plants after CO 2 fertilization for 60 days, and the largest increase range was observed in the 1000 Μmol·mol -1 CO 2 treatment, whereas the stomata conductance was significantly reduced compared with the control. Meanwhile, the contents of soluble sugar, starch and soluble protein in CO 2 -fertilized plants were significantly higher than those in control plants. Moreover, the quality of cut flowers with CO 2 fertilization was remarkably superior to control flowers in term of the parameters including spathe size, spathe color, peduncle length, leaf growth performance and peduncle growth rate. The most superior improvement was observed in the 1000 Μmol·mol -1 CO 2 treatment. It was therefore concluded that CO 2 fertilization of 1000 Μmol·mol -1 could effectively improve the winter production of cut A. andraeanum in solar greenhouse.
(E)-1-(2-Aminophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one
Chantrapromma, Suchada; Ruanwas, Pumsak; Fun, Hoong-Kun
2011-01-01
In the asymmetric unit of the title chalcone derivative, C18H19NO4, there are three crystallographically independent molecules (molecules A, B and C). In molecule A, the dihedral angle between two benzene rings is 12.22 (10)° and the plane of the central prop-2-en-1-one unit makes dihedral angles of 11.02 (13) and 2.64 (12)° with the two adjacent benzene rings. The corresponding angles in molecule B are 12.35 (10), 18.78 (12) and 7.29 (12)°, respectively, and those in molecule C are 15.40 (10), 15.62 (3) and 3.19 (13)°. In each molecule, an intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal structure, the molecules B are linked by intermolecular N—H⋯O hydrogen bonds into a zigzag chain along the c axis, while the molecules A and C are linked together via an N—H⋯O hydrogen bond into a dimer. Adjacent dimers are further connected by N—H⋯N hydrogen bonds into a three-dimensional network. Weak C—H⋯O and C—H⋯π interactions are also observed. PMID:22064816
Mansour, Abdallah Tageldein; Miao, Liang; Espinosa, Cristóbal; García-Beltrán, José María; Ceballos Francisco, Diana C; Esteban, M Ángeles
2018-08-01
The effect of the dietary incorporation of drumstick, Moringa oleifera, leaf meal (MOL; 0, 5, 10 and 15%) on the growth, feed utilization, some skin mucus and systemic immune parameters and intestinal immune-related gene expression in gilthead seabream (Sparus aurata) specimens. The experiment lasted 4 weeks. The results revealed that MOL can be incorporated in S. aurata diet up to 10% with no significant negative effect on growth and feed utilization. However, there was a significant decrease with MOL at a level of 15% after 2 weeks of feeding. The systemic immune status of fish fed with the different levels of MOL showed an improvement in head kidney leucocyte phagocytosis, respiratory burst and peroxidase activities. Also, serum humoral components, including protease, ACH 50 and lysozyme activities and IgM level, increased with MOL inclusion especially at the 5% level. MOL at 5% improved skin-mucosal immunity such as protease, antiprotease, peroxidase and lysozyme activities. Moreover, the feeding of MOL revealed an upregulation of the intestinal mucosal immunity genes (lyso and c3), tight junction proteins (occludin and zo-1) and anti-inflammatory cytokines (tgf-β) with a downregulation of pro-inflammatory cytokine (tnf-α). Therefore, it is recommended to incorporate MOL in S. aurata diets at a level of 5% for the best immune status or 10% for the high growth performance and acceptable immune surveillance. Graphical abstract ᅟ.
Jamal, Qazi Mohammad Sajid; Dhasmana, Anupam; Lohani, Mohtashim; Firdaus, Sumbul; Ansari, Md Yousuf; Sahoo, Ganesh Chandra; Haque, Shafiul
2015-01-01
Cigarette smoke derivatives like NNK (4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone) and NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butan-1-ol) are well-known carcinogens. We analyzed the interaction of enzymes involved in the NER (nucleotide excision repair) pathway with ligands (NNK and NNAL). Binding was characterized for the enzymes sharing equivalent or better interaction as compared to +Ve control. The highest obtained docking energy between NNK and enzymes RAD23A, CCNH, CDK7, and CETN2 were -7.13 kcal/mol, -7.27 kcal/mol, -8.05 kcal/mol and -7.58 kcal/mol respectively. Similarly the highest obtained docking energy between NNAL and enzymes RAD23A, CCNH, CDK7, and CETN2 were -7.46 kcal/mol, -7.94 kcal/mol, -7.83 kcal/mol and -7.67 kcal/mol respectively. In order to find out the effect of NNK and NNAL on enzymes involved in the NER pathway applying protein-protein interaction and protein-complex (i.e. enzymes docked with NNK/NNAL) interaction analysis. It was found that carcinogens are well capable to reduce the normal functioning of genes like RAD23A (HR23A), CCNH, CDK7 and CETN2. In silico analysis indicated loss of functions of these genes and their corresponding enzymes, which possibly might be a cause for alteration of DNA repair pathways leading to damage buildup and finally contributing to cancer formation.
Kurokawa, Masahiko; Wadhwani, Ashish; Kai, Hisahiro; Hidaka, Muneaki; Yoshida, Hiroki; Sugita, Chihiro; Watanabe, Wataru; Matsuno, Koji; Hagiwara, Akinori
2016-05-01
Moringa oleifera Lam. is used as a nutritive vegetable and spice. Its ethanol extract has been previously shown to be significantly effective in alleviating herpetic skin lesions in mice. In this study, we evaluated the alleviation by the aqueous extract (AqMOL) and assessed the mode of its anti-herpetic action in a murine cutaneous herpes simplex virus type 1 (HSV-1) infection model. AqMOL (300 mg/kg) was administered orally to HSV-1-infected mice three times daily on days 0 to 5 after infection. AqMOL significantly limited the development of herpetic skin lesions and reduced virus titers in the brain on day 4 without toxicity. Delayed-type hypersensitivity (DTH) reaction to inactivated HSV-1 antigen was significantly stronger in infected mice administered AqMOL and AqMOL augmented interferon (IFN)-γ production by HSV-1 antigen from splenocytes of HSV-1-infected mice at 4 days post-infection. AqMOL administration was effective in elevating the ratio of CD11b(+) and CD49b(+) subpopulations of splenocytes in infected mice. As DTH is a major host defense mechanism for intradermal HSV infection, augmentation of the DTH response by AqMOL may contribute to their efficacies against HSV-1 infection. These results provided an important insights into the mechanism by which AqMOL activates cellular immunity. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Demoulin-Alexikova, Silvia; Plevkova, Jana; Mazurova, Lenka; Zatko, Tomas; Alexik, Mikulas; Hanacek, Jan; Tatar, Milos
2016-01-01
Background: Numerous studies show higher cough reflex sensitivity (CRS) and cough outcomes in children compared to adults and in females compared to males. Despite close link that exists between cough and environment the potential influence of environmental air pollution on age- and gender -related differences in cough has not been studied yet. Purpose: The purpose of our study was to analyse whether the effects of exposure to environmental tobacco smoke (ETS) from parental smoking and PM10 from living in urban area are implied in age- and gender-related differences in cough outcomes of healthy, non-asthmatic children. Assessment of CRS using capsaicin and incidence of dry and wet cough was performed in 290 children (mean age 13.3 ± 2.6 years (138 females/152 males). Results: CRS was significantly higher in girls exposed to ETS [22.3 μmol/l (9.8–50.2 μmol/l)] compared to not exposed girls [79.9 μmol/l (56.4–112.2 μmol/l), p = 0.02] as well as compared to exposed boys [121.4 μmol/l (58.2–253.1 μmol/l), p = 0.01]. Incidence of dry cough lasting more than 3 weeks was significantly higher in exposed compared to not exposed girls. CRS was significantly higher in school-aged girls living in urban area [22.0 μmol/l (10.6–45.6 μmol/l)] compared to school-aged girls living in rural area [215.9 μmol/l (87.3–533.4 μmol/l); p = 0.003], as well as compared to teenage girls living in urban area [108.8 μmol/l (68.7–172.9 μmol/l); p = 0.007]. No CRS differences were found between urban and rural boys when controlled for age group. No CRS differences were found between school-aged and teenage boys when controlled for living area. Conclusions: Our results have shown that the effect of ETS on CRS was gender specific, linked to female gender and the effect of PM10 on CRS was both gender and age specific, related to female gender and school-age. We suggest that age and gender related differences in incidence of cough and CRS might be, at least partially, ascribed to the effect of environmental pollutants. The role of age and gender in the effect of air pollution on cough strongly suggest some interplay of development with biological and behavioral factors. PMID:26941651
Hydride affinities of cumulated, isolated, and conjugated dienes in acetonitrile.
Zhu, Xiao-Qing; Liang, Hao; Zhu, Yan; Cheng, Jin-Pei
2008-11-07
The hydride affinities (defined as the enthalpy changes in this work) of 15 polarized dienes [five phenyl sulfone substituted allenes (1a), the corresponding five isolated dienes (1b), and the corresponding five conjugated dienes (1c)] in acetonitrile solution were determined by titration calorimetry for the first time. The results display that the hydride affinity scales of the 15 dienes in acetonitrile range from -71.6 to -73.9 kcal/mol for 1a, from -46.2 to -49.7 kcal/mol for 1b, and from -45.0 to -46.5 kcal/mol for 1c, which indicates that the hydride-obtaining abilities of the cumulated dienes (1a) are not only much larger than those of the corresponding conjugated dienes (1c) but also much larger than those of the corresponding isolated dienes (1b). The hydrogen affinities of the 15 dienes as well as the hydrogen affinities and the proton affinities of the radical anions of the dienes (1(-*)) in acetonitrile were also evaluated by using relative thermodynamic cycles according to Hess's law. The results show that (i) the hydrogen affinities of the neutral dienes 1 cover a range from -44.5 to -45.6 kcal/mol for 1a, from -20.4 to -21.4 kcal/mol for 1b, and from -17.3 to -18.5 kcal/mol for 1c; (ii) the hydrogen affinities of the radical anions of the dienes (1(-*)) in acetonitrile cover a range from -40.6 to -47.2 kcal/mol for 1a(-*), from -21.6 to -29.6 kcal/mol for 1b(-*), and from -10.0 to -15.4 kcal/mol for 1c(-*); (iii) the proton affinities of the 15 1a(-*) in acetonitrile cover a range from -97.0 to -100.6 kcal/mol for 1a(-*), from -77.8 to -83.4 kcal/mol for 1b(-*), and from -66.2 to -68.9 kcal/mol for 1c(-*). The main reasons for the great difference between the cumulated dienes and the corresponding isolated and conjugated dienes in the hydride affinity, hydrogen affinity, and proton affinity have been examined. It is evident that these experimental results should be quite valuable to facilitate the elucidation of the origins of the especially high chemical potencies of the allenes, the choice of suitable hydride reducing agents to reduce the dienes, and the analyses on the reduction mechanisms.
Demoulin-Alexikova, Silvia; Plevkova, Jana; Mazurova, Lenka; Zatko, Tomas; Alexik, Mikulas; Hanacek, Jan; Tatar, Milos
2016-01-01
Numerous studies show higher cough reflex sensitivity (CRS) and cough outcomes in children compared to adults and in females compared to males. Despite close link that exists between cough and environment the potential influence of environmental air pollution on age- and gender -related differences in cough has not been studied yet. The purpose of our study was to analyse whether the effects of exposure to environmental tobacco smoke (ETS) from parental smoking and PM10 from living in urban area are implied in age- and gender-related differences in cough outcomes of healthy, non-asthmatic children. Assessment of CRS using capsaicin and incidence of dry and wet cough was performed in 290 children (mean age 13.3 ± 2.6 years (138 females/152 males). CRS was significantly higher in girls exposed to ETS [22.3 μmol/l (9.8-50.2 μmol/l)] compared to not exposed girls [79.9 μmol/l (56.4-112.2 μmol/l), p = 0.02] as well as compared to exposed boys [121.4 μmol/l (58.2-253.1 μmol/l), p = 0.01]. Incidence of dry cough lasting more than 3 weeks was significantly higher in exposed compared to not exposed girls. CRS was significantly higher in school-aged girls living in urban area [22.0 μmol/l (10.6-45.6 μmol/l)] compared to school-aged girls living in rural area [215.9 μmol/l (87.3-533.4 μmol/l); p = 0.003], as well as compared to teenage girls living in urban area [108.8 μmol/l (68.7-172.9 μmol/l); p = 0.007]. No CRS differences were found between urban and rural boys when controlled for age group. No CRS differences were found between school-aged and teenage boys when controlled for living area. Our results have shown that the effect of ETS on CRS was gender specific, linked to female gender and the effect of PM10 on CRS was both gender and age specific, related to female gender and school-age. We suggest that age and gender related differences in incidence of cough and CRS might be, at least partially, ascribed to the effect of environmental pollutants. The role of age and gender in the effect of air pollution on cough strongly suggest some interplay of development with biological and behavioral factors.
Cacanyiova, S; Berenyiova, A; Balis, P; Kristek, F; Grman, M; Ondrias, K; Breza, J; Breza, J
2017-08-01
In normotensive conditions, it has been confirmed that S-nitrosothiols (RSNO), can interact with hydrogen sulfide (H 2 S) and create new substances with specific vasoactive effects. This interaction could also represent a new regulator signaling pathway in conditions of hypertension. Until now, these effects were studied only in normotensive rats, and they have not been carried out in humans yet. We investigated the vasoactive effects of the products of the H 2 S/S-nitrosoglutathione (S/GSNO) interaction in lobar arteries (LA) isolated from the nephrectomized kidneys of patients suffering from arterial hypertension and in renal arteries (RA) of spontaneously hypertensive rats (SHR). The changes in the isometric tension of pre-contracted arteries were evaluated. Acetylcholine-induced vasorelaxation of LA was reduced compared to the effect induced by an NO donor, sodium nitroprusside suggesting an endothelium dysfunction. While 1 μmol/L Na2S had a minimal effect on the vascular tone, the concentration 20 μmol/L evoked a slight vasorelaxation. GSNO at 0.1 μmol/L induced vasorelaxation, which was less pronounced compared to the effect induced by 1 μmol/L. The S/GSNO products (final concentration 0.1 μmol/L) prepared as the mixture of GSNO (0.1 μmol/L) + Na2S (1 μmol/L) induced a higher vasorelaxation compared to GSNO (0.1 μmol/L) alone only in the 5 th minute and without the differences in the speed. On the other hand, the S/GSNO products (final concentration 1 μmol/L) prepared as the mixture of GSNO (1 μmol/L) + Na2S (10 μmol/L) induced a higher and faster vasorelaxation compared to the effect induced by GSNO (1 μmol/L) alone. In RA of SHR this S/GSNO products induced similar vasorelaxation (higher and faster than GSNO) with involvement of HNO (partially) and cGMP as mediators. However, the products of the H 2 S/NO donor (DEA NONOate) manifested differently than S/GSNO indicating the unique interaction between GSNO and H 2 S. In this study, we confirmed for the first time that specific vasoactive effects of coupled nitroso-sulfide signaling were also triggered in human arterial tissue. We suggest that in hypertension, H 2 S in interaction with GSNO regulated a vasoconstrictor-induced increase in arterial tone towards a stronger vasorelaxation compared to GSNO alone or H 2 S alone.
Zhou, Tian-Ran; Huang, Jing-Jing; Huang, Zi-Tong; Cao, Hong-Ying; Tan, Bo
2018-01-01
AIM To elucidate the mechanism of patchouli alcohol (PA) in treatment of rat models of diarrhea-predominant irritable bowel syndrome (IBS-D). METHODS We studied the effects of PA on colonic spontaneous motility using its cumulative log concentration (3 × 10−7 mol/L to 1 × 10−4 mol/L). We then determined the responses of the proximal and distal colon segments of rats to the following stimuli: (1) carbachol (1 × 10−9 mol/L to 1 × 10−5 mol/L); (2) neurotransmitter antagonists including Nω-nitro-L-arginine methyl ester hydrochloride (10 μmol/L) and (1R*, 2S*)-4-[2-Iodo-6-(methylamino)-9H-purin-9-yl]-2-(phosphonooxy)bicyclo[3.1.0]hexane-1-methanol dihydrogen phosphate ester tetraammonium salt (1 μmol/L); (3) agonist α,β-methyleneadenosine 5′-triphosphate trisodium salt (100 μmol/L); and (4) single KCl doses (120 mmol/L). The effects of blockers against antagonist responses were also assessed by pretreatment with PA (100 μmol/L) for 1 min. Electrical-field stimulation (40 V, 2-30 Hz, 0.5 ms pulse duration, and 10 s) was performed to observe nonadrenergic, noncholinergic neurotransmitter release in IBS-D rat colon. The ATP level of Kreb’s solution was also determined. RESULTS PA exerted a concentration-dependent inhibitory effect on the spontaneous contraction of the colonic longitudinal smooth muscle, and the half maximal effective concentration (EC50) was 41.9 μmol/L. In comparison with the KCl-treated IBS-D group, the contractile response (mg contractions) in the PA + KCl-treated IBS-D group (11.87 ± 3.34) was significantly decreased in the peak tension (P < 0.01). Compared with CCh-treated IBS-D rat colon, the cholinergic contractile response of IBS-D rat colonic smooth muscle (EC50 = 0.94 μmol/L) was significantly decreased by PA (EC50 = 37.43 μmol/L) (P < 0.05). Lack of nitrergic neurotransmitter release in stress-induced IBS-D rats showed contraction effects on colonic smooth muscle. Pretreatment with PA resulted in inhibitory effect on L-NAME-induced (10 μmol/L) contraction (P < 0.05). ATP might not be the main neurotransmitter involved in inhibitory effects of PA in the colonic relaxation of stress-induced IBS-D rats. CONCLUSION PA application may serve as a new therapeutic approach for IBS-D. PMID:29456408
Final report of APMP.QM-K46 ammonia in nitrogen at 30 μmol/mol level
NASA Astrophysics Data System (ADS)
Uehara, Shinji; Qiao, Han; Shimosaka, Takuya
2017-01-01
This report describes the results for a bilateral comparison of ammonia in nitrogen gas mixture. The nominal amount-of-substance fraction was 30 μmol/mol. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Fotoexcitación de Moléculas Pequeñas
NASA Astrophysics Data System (ADS)
González Díaz, P. F.
El modelo estocástico no puede justificar la excitación multi-fotónica de moléculas pequeñas o muy simétricas. Basándonos en un escenario de interacción radiación-molécula cooperativo para la absorción de N-1 fotones IR por un sistema de N niveles, se especula que un posible mecanismo para la excitación no estocástica de moléculas pudiera ser la generación de procesos caóticos intra-moleculares.
Li corrosion resistant glasses for headers in ambient temperature Li batteries
Hellstrom, E.E.; Watkins, R.D.
1985-10-11
Glass compositions containing 10 to 50 mol% CaO, 10 to 50 mol% Al/sub 2/O/sub 3/, 30 to 60 mol% B/sub 2/O/sub 3/, and 0 to 30 mol% MgO are provided. These compositions are capable of forming a stable glass-to-metal seal possessing electrical insulating properties for use in a lithium battery. Also provided are lithium cells containing a stainless steel body and molybdenum center pin electrically insulated by means of a seal produced according to the invention.
Benzene-1,4-diol–5-(1H-imidazol-1-yl)pyrimidine (1/1)
Jiang, Yan-Ke; Hou, Gui-Ge
2011-01-01
The asymmetric unit of title compound, C7H6N4·C6H6O2, contains one 5-(1H-imidazol-1-yl)pyrimidine molecule and two half benzene-1,4-diol molecules; the benzene-1,4-diol molecules are located on individual inversion centers. In the pyrimidine molecule, the imidazole ring is twisted with respect to the pyrimidine ring at a dihedral angle of 25.73 (7)°. In the crystal, O—H⋯N hydrogen bonds link the molecules to form supramolecular chains. π–π stacking is also observed in the crystal, the centroid–centroid distance between parallel imdazole rings being 3.5543 (16) Å. PMID:22220081
Optimized MOL-PCR for Characterization of Microbial Pathogens.
Wuyts, Véronique; Roosens, Nancy H C; Bertrand, Sophie; Marchal, Kathleen; De Keersmaecker, Sigrid C J
2016-01-06
Characterization of microbial pathogens is necessary for surveillance, outbreak detection, and tracing of outbreak sources. This unit describes a multiplex oligonucleotide ligation-PCR (MOL-PCR) optimized for characterization of microbial pathogens. With MOL-PCR, different types of markers, like unique sequences, single-nucleotide polymorphisms (SNPs) and indels, can be simultaneously analyzed in one assay. This assay consists of a multiplex ligation for detection of the markers, a singleplex PCR for signal amplification, and hybridization to MagPlex-TAG beads for readout on a Luminex platform after fluorescent staining. The current protocol describes the MOL-PCR, as well as methods for DNA isolation, probe design, and data interpretation and it is based on an optimized MOL-PCR assay for subtyping of Salmonella Typhimurium. Copyright © 2016 John Wiley & Sons, Inc.
4-Amino-N-(3-methoxypyrazin-2-yl)benzenesulfonamide
Bruni, Bruno; Coran, Silvia A.; Bartolucci, Gianluca; Di Vaira, Massimo
2010-01-01
The overall molecular geometry of the title compound, C11H12N4O3S, is bent, with a dihedral angle of 89.24 (5)° between the best planes through the two aromatic rings. Each molecule behaves as a hydrogen-bond donor toward three different molecules, through its amidic and the two aminic H atoms, and it behaves as a hydrogen-bond acceptor from two other molecules via one of its sulfonamidic O atoms. In the crystal, molecules linked by N—H⋯N and N—H⋯O hydrogen bonds form kinked layers parallel to (001), adjacent layers being connected by van der Waals interactions. PMID:21587634
Alumina-Reinforced Zirconia Composites
NASA Technical Reports Server (NTRS)
Choi, Sung R.; Bansal, Narottam P.
2003-01-01
Alumina-reinforced zirconia composites, used as electrolyte materials for solid oxide fuel cells, were fabricated by hot pressing 10 mol percent yttria-stabilized zirconia (10-YSZ) reinforced with two different forms of alumina particulates and platelets each containing 0 to 30 mol percent alumina. Major mechanical and physical properties of both particulate and platelet composites including flexure strength, fracture toughness, slow crack growth, elastic modulus, density, Vickers microhardness, thermal conductivity, and microstructures were determined as a function of alumina content either at 25 C or at both 25 and 1000 C. Flexure strength and fracture toughness at 1000 C were maximized with 30 particulate and 30 mol percent platelet composites, respectively, while resistance to slow crack growth at 1000 C in air was greater for 30 mol percent platelet composite than for 30 mol percent particulate composites.
Fun, Hoong-Kun; Kia, Reza; Maity, Annada C.; Chakrabarty, Rinku; Goswami, Shyamaprosad
2009-01-01
The title compound, C20H14N2, comprises two crystallographically independent centrosymmetric molecules (A and B) with different conformations due to the disorder of molecule B. The whole of molecule B is disordered over two sets of positions, corresponding to a 180° rotation of the molecule, with a site-occupancy ratio of 0.780 (6):0.220 (6). The minor component of the disordered part in B has the same configuration as molecule A, but the major component is different. The dihedral angle between the planes of molecule A and molecule B (major component) is 63.22 (3)°. The crystal structure is stabilized by intermolecular C—H⋯π interactions. PMID:21581953
Meor Mohd Affandi, M M R; Tripathy, Minaketan; Shah, Syed Adnan Ali; Majeed, A B A
2016-01-01
We examined the solubility of simvastatin in water in 0.01 mol·dm(-3), 0.02 mol·dm(-3), 0.04 mol·dm(-3), 0.09 mol·dm(-3), 0.18 mol·dm(-3), 0.36 mol·dm(-3), and 0.73 mol·dm(-3) arginine (ARG) solutions. The investigated drug is termed the solute, whereas ARG the cosolute. Phase solubility studies illustrated a higher extent of solubility enhancement for simvastatin. The aforementioned system was subjected to conductometric and volumetric measurements at temperatures (T) of 298.15 K, 303.15 K, 308.15 K, and 313.15 K to illustrate the thermodynamics involved and related solute-solvent interactions. The conductance values were used to evaluate the limiting molar conductance and association constants. Thermodynamic parameters (ΔG (0), ΔH (0), ΔS (0), and E s) for the association process of the solute in the aqueous solutions of ARG were calculated. Limiting partial molar volumes and expansibilities were evaluated from the density values. These values are discussed in terms of the solute-solvent and solute-cosolute interactions. Further, these systems were analyzed using ultraviolet-visible analysis, Fourier-transform infrared spectroscopy, and (13)C, (1)H, and two-dimensional nuclear overhauser effect spectroscopy nuclear magnetic resonance to complement thermophysical explanation.
Hydration Resistance of Y2O3 Doped CaO and Its Application to Melting Titanium Alloys
NASA Astrophysics Data System (ADS)
Fanlong, Meng; Zhiwei, Cheng; Guangyao, Chen; Xionggang, Lu; Chonghe, Li
Various amount Y2O3(1-8 mol%) doped CaO powder was synthesized by the solid state reaction method, the pellete and crucible were fabricated by the cold isostatic pressing and were sintered at 1750°C for 4h. The microstructural characterization was revealed by X-ray diffraction(XRD) and scanning electron microscopy(SEM).The XRD results showed that when Y2O3 doped 2 mol%, metastable CaY2O4 phase existed in CaO grain boundary, when Y2O3 doped 3 mol%-8 mol%, in addition to the above structure, Y2O3 phase also be found in CaO grain boundary. Hydration experiment results showed when Y2O3 doped 0 mol%-4 mol%, CaO had excellent hydration resistance performance, Y2O3 doped 2 mol% had the best hydration resistance, its weight addition stored after 7 weeks (49 days) was only about 0.2 wt%. Melting experiment results showed that it was no reaction between crucible and alloy layer. Oxygen, calcium, titanium, nickle and yttrium element not diffusion between the CaO crucible and TiNi alloy, it was no oxygen content increase after melting.
(2E)-3-(6-Methoxynaphthalen-2-yl)-1-[4-(methylsulfanyl)phenyl]prop-2-en-1-one
Fun, Hoong-Kun; Chia, Tze Shyang; Padaki, Mahesh; Isloor, Arun M.; Ismail, A. F.
2012-01-01
The asymmetric unit of the title compound, C21H18O2S, consists of two crystallographically independent molecules (A and B). The molecules exist in a trans conformation with respect to the central C=C bond. The naphthalene ring system makes dihedral angles of 51.62 (12) (molecule A) and 52.69 (12)° (molecule B) with the benzene ring. In molecule A, the prop-2-en-1-one group forms dihedral angles of 22.84 (15) and 29.02 (12)° with the adjacent naphthalene ring system and benzene ring, respectively, whereas the corresponding angles are 30.04 (12) and 23.33 (12)° in molecule B. In the crystal, molecules are linked by intermolecular C—H⋯O hydrogen bonds into head-to-tail chains along the a axis. The crystal packing also features C—H⋯π interactions. The crystal studied was a pseudo-merohedral twin with twin law (100 0-10 00-1) and a refined component ratio of 0.6103 (16):0.3897 (16). PMID:22798922
4-Bromo-N-(di-n-propyl-carbamothioyl)-benzamide.
Binzet, Gün; Flörke, Ulrich; Külcü, Nevzat; Arslan, Hakan
2009-02-04
The synthesis of the title compound, C(14)H(19)BrN(2)OS, involves the reaction of 4-bromo-benzoyl chloride with potassium thio-cyanate in acetone followed by condensation of the resulting 4-bromo-benzoyl isothio-cyanate with di-n-propyl-amine. Typical thio-urea carbonyl and thio-carbonyl double bonds, as well as shortened C-N bonds, are observed in the title compound. The short C-N bond lengths in the centre of the mol-ecule reveal the effects of resonance in this part of the mol-ecule. The asymmetric unit of the title compound contains two crystallographically independent mol-ecules, A and B. There is very little difference between the bond lengths and angles of these mol-ecules. In mol-ecule B, one di-n-propyl group is twisted in a -anti-periplanar conformation with C-C-C-H = -179.1 (3)° and the other adopts a -synclinal conformation with C-C-C-H = -56.7 (4)°; in mol-ecule A the two di-n-propyl groups are twisted in + and -anti-periplanar conformations, with C-C-C-H = -179.9 (3) and 178.2 (3)°, respectively. In the crystal, the mol-ecules are linked into dimeric pairs via pairs of N-H⋯S hydrogen bonds.
Raja, S; Thangaradjou, T; Sivakumar, K; Kannan, L
2012-11-01
Seagrass rhizosphere generally supports high bacterial population density which plays a major role in determining the nutrient cycles of the sea. Higher densities of total heterotrphic bacteria (26.3 x 10(6) CFU g(-1)), nitrogen fixing (27.3 x 10(3) CFUg(-1), ammonifying (44.66 x 10(6) MPN g(-1)) and nitrifying bacteria (42.33 X 10(6) MPN g(-1)) have been registered in the seagrass areas than the non seagrass area. In particular, all these rhizosphere microbial population was higher in Thalassia hemprichii. The rates of nitrogen fixation was recorded in the different species of seagrasses such as Enhalus acoroides (1.166 n mol g(-1) d(-1)), Halophila ovalis (0.166 n mol g(-1) d(-1)), Thalassia hemprichii(18.5 n mol g(-1) d(-1)), Cymodocea serrulata (10.5 n mol g(-1) d(-1)), Halodule uninervis (5.375 n mol g(-1) d(-1)) and Syringodium isoetifolium (0.666 n mol g(-1) d(-1)) using gas chromatography. The average nitrogen fixation by the seagrasses of Gulf of Mannar alone was estimated to be 7640.58 n mol m(-2) d(-1) and the contributions from the rhizosphere microbes will increase the quantity to many fold.
Chen, Tinggui; Li, Yayun; Zhang, Liwei
2017-05-12
It is difficult to screen out as many active components as possible from natural plants all at one time. In this study, subfractions of Forsythia suspensa leaves were firstly prepared; then, their inhibitive abilities on pancreatic lipase were tested; finally, the highest inhibiting subfraction was screened by self-made immobilized pancreatic lipase. Results showed that nine ligands, including eight inhibitors and one promotor, were screened out all at one time. They were three flavonoids (rutin, IC 50 : 149 ± 6.0 μmol/L; hesperidin, 52.4 μmol/L; kaempferol-3- O -rutinoside, isolated from F. suspensa leaves for the first time, IC 50 notably reached 2.9 ± 0.5 μmol/L), two polyphenols (chlorogenic acid, 3150 ± 120 μmol/L; caffeic acid, 1394 ± 52 μmol/L), two lignans (phillyrin, promoter; arctigenin, 2129 ± 10.5 μmol/L), and two phenethyl alcohol (forsythiaside A, 2155 ± 8.5 μmol/L; its isomer). Their action mechanisms included competitive inhibition, competitive promotion, noncompetitive inhibition, and uncompetitive inhibition. In sum, using the appropriate methods, more active ingredients can be simply and quickly screened out all at one time from a complex natural product system. In addition, F. suspensa leaves contain numerous inhibitors of pancreatic lipase.
Meor Mohd Affandi, MMR; Tripathy, Minaketan; Shah, Syed Adnan Ali; Majeed, ABA
2016-01-01
We examined the solubility of simvastatin in water in 0.01 mol·dm−3, 0.02 mol·dm−3, 0.04 mol·dm−3, 0.09 mol·dm−3, 0.18 mol·dm−3, 0.36 mol·dm−3, and 0.73 mol·dm−3 arginine (ARG) solutions. The investigated drug is termed the solute, whereas ARG the cosolute. Phase solubility studies illustrated a higher extent of solubility enhancement for simvastatin. The aforementioned system was subjected to conductometric and volumetric measurements at temperatures (T) of 298.15 K, 303.15 K, 308.15 K, and 313.15 K to illustrate the thermodynamics involved and related solute–solvent interactions. The conductance values were used to evaluate the limiting molar conductance and association constants. Thermodynamic parameters (ΔG0, ΔH0, ΔS0, and Es) for the association process of the solute in the aqueous solutions of ARG were calculated. Limiting partial molar volumes and expansibilities were evaluated from the density values. These values are discussed in terms of the solute–solvent and solute–cosolute interactions. Further, these systems were analyzed using ultraviolet–visible analysis, Fourier-transform infrared spectroscopy, and 13C, 1H, and two-dimensional nuclear overhauser effect spectroscopy nuclear magnetic resonance to complement thermophysical explanation. PMID:27041998
NASA Astrophysics Data System (ADS)
Zona, Robert; Solar, Sonja
2003-02-01
The gamma-radiation-induced degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in aerated (A) and in during irradiation air saturated (AS) solutions. Whereas the decomposition rates were not influenced by AS, chloride elimination, detoxification as well as mineralization were significantly enhanced. In the range 50-500 μmol dm -3 2,4-D, degradation showed proportionality to concentration, while chloride formation was successively retarded. The ratios of the pseudo first-order rate constants for degradation and chloride formation, kde/ kCl, increase in AS solutions from 1.4 (50 μmol dm -3) to 2.7 (500 μmol dm -3) and in A solutions from 1.4 to 3.3. In AS for total chloride release 0.7 kGy (50 μmol dm -3) to 10 kGy (500 μmol dm -3) were required, the reduction of organic carbon at 10 kGy was 95% (50 μmol dm -3) and 50% (500 μmol dm -3). Increase and decrease of toxicity during irradiation correlated well with formation and degradation of intermediate phenolic products. The doses for detoxification corresponded to those of total dehalogenation. The oxygen uptake was ˜1.1 ppm 100 Gy -1. The presence of the inorganic components of Vienna drinking water affect the degradation parameters insignificantly.
Béder, I; Orgonásová, M; Brozman, B; Horecký, J; Mataseje, A
1990-05-01
The regulatory effect of 2,3-DPG on oxygen transport and binding to hemoglobin was analyzed. Under conditions of substitution hemodilution by isooncotic 3.4% Rheodextran (Spofa), changes in the content of 2,3-DPG in arterial and venous blood were enzymatically determined over several days. Reference values of 2,3-DPG were obtained in the studied series of dogs (2.05 +/- 0.74 x 10(-6) mol.ml-1 in whole blood 4.69 +/- 1.52 x 10(-6) mol.g-1 of erythrocyte volume, and 13.39 +/- 2.82 x 10(-6) mol.ml-1 of hemoglobin). In anesthetized animals the content of 2,3-DPG in arterial blood was significantly higher (6.28 +/- 0.84 x 10(-6) mol.ml-1 of erythrocyte volume) than in venous blood (6.01 +/- 0.80 x 10(-6) mol.ml-1 of erythrocyte volume). At substitution hemodilution the 2,3-DPG content in erythrocytes of venous blood decreased from 5.46 +/- 0.67 to 4.97 +/- 1.31 x 10(-6) mol.ml-1 of erythrocyte volume. The subsequent increase to 6.04 +/- 0.71 x 10(-6) mol.ml-1 of erythrocyte volume was achieved by nonlinear increase over the following days, at persisting low hemoglobin content in blood.
2,2′-Bi(9,9-diethylfluorene)
Park, Ki-Min; Oh, Hankook; Kang, Youngjin
2014-01-01
The title compound, C34H34, systematic name 9,9,9′,9′-tetraethyl-2,2′-bi(9H-fluorene), crystallized with two crystallographically independent molecules (A and B) in the asymmetric unit. These differ mainly in the orientation of the lateral ethyl chains: in molecule A, they are both on the same side of the molecule whereas in molecule B, one diethylfluorene moiety has undergone a 180° rotation such that the two pairs of ethyl residues appear on opposite sides of the molecule. The fluorene ring systems subtend dihedral angles of 31.37 (4) and 43.18 (3)° in molecules A and B, respectively. Hence the two fluorene moieties are tilted slightly toward one another. This may be due to the presence of intermolecular C—H⋯π interactions between neighboring molecules. The lateral ethyl chains (excluding H atoms) are also almost planar, with each pair almost perpendicular to the plane of the fluorene system to which they are attached with dihedral angles between the ethyl and fluorene planes in the range 86.04 (8)–89.5 (1)°. PMID:24764898
NASA Astrophysics Data System (ADS)
Kysel, Ondrej; Budzák, Scaronimon; Medveď, Miroslav; Mach, Pavel
Geometry, thermodynamic, and electric properties of the pi-EDA complex between hexamethylbenzene (HMB) and tetracyanoethylene (TCNE) are investigated at the MP2/6-31G* and, partly, DFT-D/6-31G* levels. Solvent effects on the properties are evaluated using the PCM model. Fully optimized HMB-TCNE geometry in gas phase is a stacking complex with an interplanar distance 2.87 × 10-10 m and the corresponding BSSE corrected interaction energy is -51.3 kJ mol-1. As expected, the interplanar distance is much shorter in comparison with HF and DFT results. However the crystal structures of both (HMB)2-TCNE and HMB-TCNE complexes have interplanar distances somewhat larger (3.18 and 3.28 × 10-10 m, respectively) than our MP2 gas phase value. Our estimate of the distance in CCl4 on the basis of PCM solvent effect study is also larger (3.06-3.16 × 10-10 m). The calculated enthalpy, entropy, Gibbs energy, and equilibrium constant of HMB-TCNE complex formation in gas phase are: DeltaH0 = -61.59 kJ mol-1, DeltaSc0 = -143 J mol-1 K-1, DeltaG0 = -18.97 kJ mol-1, and K = 2,100 dm3 mol-1. Experimental data, however, measured in CCl4 are significantly lower: DeltaH0 = -34 kJ mol-1, DeltaSc0 = -70.4 J mol-1 K-1, DeltaG0 = -13.01 kJ mol-1, and K = 190 dm3 mol-1. The differences are caused by solvation effects which stabilize more the isolated components than the complex. The total solvent destabilization of Gibbs energy of the complex relatively to that of components is equal to 5.9 kJ mol-1 which is very close to our PCM value 6.5 kJ mol-1. MP2/6-31G* dipole moment and polarizabilities are in reasonable agreement with experiment (3.56 D versus 2.8 D for dipole moment). The difference here is due to solvent effect which enlarges interplanar distance and thus decreases dipole moment value. The MP2/6-31G* study supplemented by DFT-D parameterization for enthalpy calculation, and by the PCM approach to include solvent effect seems to be proper tools to elucidate the properties of pi-EDA complexes.
DFT study of gases adsorption on sharp tip nano-catalysts surface for green fertilizer synthesis
NASA Astrophysics Data System (ADS)
Yahya, Noorhana; Irfan, Muhammad; Shafie, Afza; Soleimani, Hassan; Alqasem, Bilal; Rehman, Zia Ur; Qureshi, Saima
2016-11-01
The energy minimization and spin modifications of sorbates with sorbents in magnetic induction method (MIM) play a vital role in yield of fertilizer. Hence, in this article the focus of study is the interaction of sorbates/reactants (H2, N2 and CO2) in term of average total adsorption energies, average isosteric heats of adsorption energies, magnetic moments, band gaps energies and spin modifications over identical cone tips nanocatalyst (sorbents) of Fe2O3, Fe3O4 (magnetic), CuO and Al2O3 (non-magnetic) for green nano-fertilizer synthesis. Study of adsorption energy, band structures and density of states of reactants with sorbents are purely classical and quantum mechanical based concepts that are vividly illustrated and supported by ADSORPTION LOCATOR and Cambridge Seriel Total Energy Package (CASTEP) modules following classical and first principle DFT simulation study respectively. Maximum values of total average energies, total average adsorption energies and average adsorption energies of H2, N2 and CO2 molecules are reported as -14.688 kcal/mol, -13.444 kcal/mol, -3.130 kcal/mol, - kcal/mol and -6.348 kcal/mol over Al2O3 cone tips respectively and minimum over magnetic cone tips. Whereas, the maximum and average minimum values of average isosteric heats of adsorption energies of H2, N2 and CO2 molecules are figured out to be 3.081 kcal/mol, 4.842 kcal/mol and 6.848 kcal/mol, 0.988 kcal/mol, 1.554 kcal/mol and 2.236 kcal/mol over aluminum oxide and Fe3O4 cone tips respectively. In addition to the adsorption of reactants over identical cone sorbents the maximum and minimum values of net spin, electrons and number of bands for magnetite and aluminum oxide cone structures are attributed to 82 and zero, 260 and 196, 206 and 118 for Fe3O4 and Al2O3 cones respectively. Maximum and least observed values of band gap energies are figured out to be 0.188 eV and 0.018 eV with Al2O3 and Fe3O4 cone structures respectively. Ultimately, with the adsorption of reactants an identical increment of 14 electrons each in up and down spins is resulted.
Li, H H; Cai, Q; Wang, Y P; Liu, H R; Huang, M
2016-07-20
Objective: To investigate the effects of Paraquat on human embryonic lung fibroblasts (MRC5) and explore the role of transforming growth factor-β 1 /connective tissue growth factor signaling pathway in paraquat-induced pulmonary fibrosis. Methods: MRC5 cells were cultured with different concentration of PQ (0, 12.5, 25, 50, 100, 200, 400 μmol/L) for 24 h. The viability of cells was measured by MTT. The protein level of TGF-β 1 were analyzed by ELISA after PQ treatment (0, 25, 50, 100 μmol/L) . To examine whether TGF-β 1 /CTGF signaling pathway was involved in paraquat-induced cytotoxicity, cells was divided into 6 groups: (1) control; (2) 25 μmol/L PQ group; (3) 50 μmol/L PQ group; (4) 100 μmol/L PQ group; (5) TGF-β 1 positive control group (50 μmol/L rhTGF-β 1 ) ; (6) stimulate group (100 μmol/L PQ+50 μmol/L TGF-β 1 ) . The protein levels of p-Smad2, p-Smad3 and CTGF were assayed by western blot. The mRNA level of CTGF was assayed by real time RT-PCR. Results: MTT showed that cell viability decreased with increasing PQ concentration ( P <0.05) . The protein expression of TGF-β 1 treated with PQ (25, 50, 100 μmol/L) significantly increased compared with control in a dose-independent manner ( P <0.05) . Exposure to PQ (25, 50, 100 μmol/L) induced increase of protein levels of p-Smad2 and p-Smad3. Noteworthy, the expression of p-Smad2 and p-Smad3 were dramatically increased following PQ plus TGF-β 1 stimulation ( P <0.05) . Exposure to PQ (50, 100μmol/L) induced increase of CTGF protein expression and similar greatly increase following PQ plus TGF-β 1 stimulation ( P <0.05) . Real time RT-PCR showed CTGF mRNA in all groups also significantly up-regulated compared with control ( P <0.05) . Conclusion: TGF-β 1 regulates the expression of target gene CTGF to exhibit its pro-fibrogenic effects by activating TGF-β 1 /Smad signaling pathway in PQ-induced pulmonary fibrosis.
Carbon monoxide contributes to the constipating effects of granisetron in rat colon.
Nacci, Carmela; Fanelli, Margherita; Potenza, Maria Assunta; Leo, Valentina; Montagnani, Monica; De Salvia, Maria Antonietta
2016-11-14
To investigate the mechanisms underlying the potential contribution of the heme oxygenase/carbon monoxide (HO/CO) pathway in the constipating effects of granisetron. For in vivo studies, gastrointestinal motility was evaluated in male rats acutely treated with granisetron [25, 50, 75 μg/kg/subcutaneous (sc)], zinc protoporphyrin IX [ZnPPIX, 50 μg/kg/intraperitoneal (ip)] and hemin (50 μmol/L/kg/ip), alone or in combination. For in vitro studies, the contractile neurogenic response to electrical field stimulation (EFS, 3, 5, 10 Hz, 14 V, 1 ms, pulse trains lasting 10 s), as well as the contractile myogenic response to acetylcholine (ACh, 0.1-100 μmol/L) were evaluated on colon specimens incubated with granisetron (3 μmol/L, 15 min), ZnPPIX (10 μmol/L, 60 min) or CO-releasing molecule-3 (CORM-3, 100, 200, 400 μmol/L) alone or in combination. These experiments were performed under co-treatment with or without atropine (3 μmol/L, a muscarinic receptor antagonist) or N G -nitro-L-Arginine (L-NNA, 100 μmol/L, a nitric oxide synthase inhibitor). Administration of granisetron (50, 75 μg/kg) in vivo significantly increased the time to first defecation ( P = 0.045 vs vehicle-treated rats), clearly suggesting a constipating effect of this drug. Although administration of ZnPPIX or hemin alone had no effect on this gastrointestinal motility parameter, ZnPPIX co-administered with granisetron abolished the granisetron-induced constipation. On the other hand, co-administration of hemin and granisetron did not modify the increased constipation observed under granisetron alone. When administered in vitro , granisetron alone (3 μmol/L) did not significantly modify the colon's contractile response to either EFS or ACh. Incubation with ZnPPIX alone (10 μmol/L) significantly reduced the colon's contractile response to EFS ( P = 0.016) but had no effect on contractile response to ACh. Co-administration of ZnPPIX and atropine (3 μmol/L) abolished the ZnPPIX-mediated decrease in contractile response to EFS. Conversely, incubation with CORM-3 (400 μmol/L) alone increased both the contractile response to EFS at 10 Hz (10 Hz: 71.02 ± 19.16 vs 116.25 ± 53.70, P = 0.01) and the contractile response to ACh (100 μmol/L) ( P = 0.012). Co-administration of atropine abolished the CORM-3-mediated effects on the EFS-mediated response. When granisetron was co-incubated in vitro with ZnPPIX, the ZnPPIX-mediated decrease in colon contractile response to EFS was lost. On the other hand, co-incubation of granisetron and CORM-3 (400 μmol/L) further increased the colon's contractile response to EFS (at 5 Hz: P = 0.007; at 10 Hz: P = 0.001) and to ACh (ACh 10 μmol/L: P = 0.001; ACh 100 μmol/L: P = 0.001) elicited by CORM-3 alone. L-NNA co-administered with granisetron and CORM-3 abolished the potentiating effect of CORM-3 on granisetron on both the EFS-induced and ACh-induced contractile response. Taken together, findings from in vivo and in vitro studies suggest that the HO/CO pathway is involved in the constipating effects of granisetron.
Carbon monoxide contributes to the constipating effects of granisetron in rat colon
Nacci, Carmela; Fanelli, Margherita; Potenza, Maria Assunta; Leo, Valentina; Montagnani, Monica; De Salvia, Maria Antonietta
2016-01-01
AIM To investigate the mechanisms underlying the potential contribution of the heme oxygenase/carbon monoxide (HO/CO) pathway in the constipating effects of granisetron. METHODS For in vivo studies, gastrointestinal motility was evaluated in male rats acutely treated with granisetron [25, 50, 75 μg/kg/subcutaneous (sc)], zinc protoporphyrin IX [ZnPPIX, 50 μg/kg/intraperitoneal (ip)] and hemin (50 μmol/L/kg/ip), alone or in combination. For in vitro studies, the contractile neurogenic response to electrical field stimulation (EFS, 3, 5, 10 Hz, 14 V, 1 ms, pulse trains lasting 10 s), as well as the contractile myogenic response to acetylcholine (ACh, 0.1-100 μmol/L) were evaluated on colon specimens incubated with granisetron (3 μmol/L, 15 min), ZnPPIX (10 μmol/L, 60 min) or CO-releasing molecule-3 (CORM-3, 100, 200, 400 μmol/L) alone or in combination. These experiments were performed under co-treatment with or without atropine (3 μmol/L, a muscarinic receptor antagonist) or NG-nitro-L-Arginine (L-NNA, 100 μmol/L, a nitric oxide synthase inhibitor). RESULTS Administration of granisetron (50, 75 μg/kg) in vivo significantly increased the time to first defecation (P = 0.045 vs vehicle-treated rats), clearly suggesting a constipating effect of this drug. Although administration of ZnPPIX or hemin alone had no effect on this gastrointestinal motility parameter, ZnPPIX co-administered with granisetron abolished the granisetron-induced constipation. On the other hand, co-administration of hemin and granisetron did not modify the increased constipation observed under granisetron alone. When administered in vitro, granisetron alone (3 μmol/L) did not significantly modify the colon’s contractile response to either EFS or ACh. Incubation with ZnPPIX alone (10 μmol/L) significantly reduced the colon’s contractile response to EFS (P = 0.016) but had no effect on contractile response to ACh. Co-administration of ZnPPIX and atropine (3 μmol/L) abolished the ZnPPIX-mediated decrease in contractile response to EFS. Conversely, incubation with CORM-3 (400 μmol/L) alone increased both the contractile response to EFS at 10 Hz (10 Hz: 71.02 ± 19.16 vs 116.25 ± 53.70, P = 0.01) and the contractile response to ACh (100 μmol/L) (P = 0.012). Co-administration of atropine abolished the CORM-3-mediated effects on the EFS-mediated response. When granisetron was co-incubated in vitro with ZnPPIX, the ZnPPIX-mediated decrease in colon contractile response to EFS was lost. On the other hand, co-incubation of granisetron and CORM-3 (400 μmol/L) further increased the colon’s contractile response to EFS (at 5 Hz: P = 0.007; at 10 Hz: P = 0.001) and to ACh (ACh 10 μmol/L: P = 0.001; ACh 100 μmol/L: P = 0.001) elicited by CORM-3 alone. L-NNA co-administered with granisetron and CORM-3 abolished the potentiating effect of CORM-3 on granisetron on both the EFS-induced and ACh-induced contractile response. CONCLUSION Taken together, findings from in vivo and in vitro studies suggest that the HO/CO pathway is involved in the constipating effects of granisetron. PMID:27895421
Li, Peng-Yun; Zeng, Xiao-Rong; Yang, Yan; Cai, Fang; Li, Miao-Ling; Liu, Zhi-Fei; Pei, Jie; Zhou, Wen
2008-02-25
The aim of the present study was to investigate the effects of inositol 1,4,5-trisphosphate (IP(3))-generating agonist UTP on spontaneous transient outward currents (STOCs), and explore the role of intracellular Ca(2+) release in the current response mediated by IP(3) in porcine coronary artery smooth muscle cells (CASMCs). The coronary artery was excised from the fresh porcine heart and cut into small segments (2 mm × 5 mm) and then transferred to enzymatic dissociation solution for incubation. Single CASMCs were obtained by two-step enzyme digestion at 37 °C. STOCs were recorded and characterized using the perforated whole-cell patch-clamp configuration in freshly isolated porcine CASMCs. The currents were amplified and filtered by patch-clamp amplifier (Axopatch 200B), and then the digitized data were recorded by pClamp 9.0 software and further analyzed by MiniAnalysis 6.0 program. The results were as follows: (1) UTP led to conspicuous increases in STOC amplitude by (57.54±5.34)% and in frequency by (77.46±8.42)% (P<0.01, n=38). (2) The specific blocker of phospholipase C (PLC) - U73122 (5 μmol/L) remarkably reduced STOC amplitude by (31.04±7.46)% and frequency by (41.65±16.59)%, respectively (P<0.05, n=10). In the presence of U73122, UTP failed to reactivate STOCs (n=7). (3) Verapamil (20 μmol/L) and CdCl2 (200 μmol/L), two blockers of L-type voltage-dependent Ca(2+) channels, had little effects on STOCs initiated by UTP (n=8). (4) 1 μmol/L bisindolylmaleimide I (BisI), a potent blocker of protein kinase C (PKC), significantly increased STOC amplitude by (65.44±24.66)% and frequency by (61.35±21.47)% (P<0.01, n=12); UTP (40 μmol/L), applied in the presence of 1 μmol/L BisI, could further increase STOC activity (P<0.05, P<0.01, n=12). Subsequent application of ryanodine (50 μmol/L) abolished STOC activity. (5) In the presence of UTP (40 μmol/L), inhibition of IP(3) receptors (IP(3)Rs) by 2-aminoethoxydiphenyl borate (2-APB, 40 μmol/L) reduced STOC amplitude by (24.08±3.97)% (P<0.05, n=8), but had little effect on STOC frequency (n=8). While application of 2-APB (80 μmol/L) significantly reduced STOC amplitude by (31.43±6.34)% and frequency by (40.59±19.01)%, respectively (P<0.05, P<0.01, n=6). Subsequent application of ryanodine (50 μmol/L) completely blocked STOC activity. Pretreatment of cells with 2-APB (40 μmol/L) or ryanodine (50 μmol/L), UTP (40 μmol/L) failed to reactivate STOCs. The results suggest that UTP activates STOCs mainly via PLC and IP(3)-dependent mechanisms. Complex Ca(2+)-mobilization pathways are involved in UTP-mediated STOC activation in porcine CASMCs.
Excel-Based Tool for Pharmacokinetically Guided Dose Adjustment of Paclitaxel.
Kraff, Stefanie; Lindauer, Andreas; Joerger, Markus; Salamone, Salvatore J; Jaehde, Ulrich
2015-12-01
Neutropenia is a frequent and severe adverse event in patients receiving paclitaxel chemotherapy. The time above a paclitaxel threshold concentration of 0.05 μmol/L (Tc > 0.05 μmol/L) is a strong predictor for paclitaxel-associated neutropenia and has been proposed as a target pharmacokinetic (PK) parameter for paclitaxel therapeutic drug monitoring and dose adaptation. Up to now, individual Tc > 0.05 μmol/L values are estimated based on a published PK model of paclitaxel by using the software NONMEM. Because many clinicians are not familiar with the use of NONMEM, an Excel-based dosing tool was developed to allow calculation of paclitaxel Tc > 0.05 μmol/L and give clinicians an easy-to-use tool. Population PK parameters of paclitaxel were taken from a published PK model. An Alglib VBA code was implemented in Excel 2007 to compute differential equations for the paclitaxel PK model. Maximum a posteriori Bayesian estimates of the PK parameters were determined with the Excel Solver using individual drug concentrations. Concentrations from 250 patients were simulated receiving 1 cycle of paclitaxel chemotherapy. Predictions of paclitaxel Tc > 0.05 μmol/L as calculated by the Excel tool were compared with NONMEM, whereby maximum a posteriori Bayesian estimates were obtained using the POSTHOC function. There was a good concordance and comparable predictive performance between Excel and NONMEM regarding predicted paclitaxel plasma concentrations and Tc > 0.05 μmol/L values. Tc > 0.05 μmol/L had a maximum bias of 3% and an error on precision of <12%. The median relative deviation of the estimated Tc > 0.05 μmol/L values between both programs was 1%. The Excel-based tool can estimate the time above a paclitaxel threshold concentration of 0.05 μmol/L with acceptable accuracy and precision. The presented Excel tool allows reliable calculation of paclitaxel Tc > 0.05 μmol/L and thus allows target concentration intervention to improve the benefit-risk ratio of the drug. The easy use facilitates therapeutic drug monitoring in clinical routine.
American Society of Composites, 32nd Technical Conference
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aitharaju, Venkat; Wollschlager, Jeffrey; Plakomytis2, Dimitrios
This paper will present a general methodology by which weave draping manufacturing simulation results can be utilized to include the effects of weave draping and scissor angle in a structural multiscale simulation. While the methodology developed is general in nature, this paper will specifically demonstrate the methodology applied to a truncated pyramid, utilizing manufacturing simulation weave draping results from ESI PAM-FORM, and multiscale simulation using Altair Multiscale Designer (MDS) and OptiStruct. From a multiscale simulation perspective, the weave draping manufacturing simulation results will be used to develop a series of woven unit cells which cover the range of weave scissormore » angles existing within the part. For each unit cell, a multiscale material model will be developed, and applied to the corresponding spatial locations within the structural simulation mesh. In addition, the principal material orientation will be mapped from the wave draping manufacturing simulation mesh to the structural simulation mesh using Altair HyperMesh mapping technology. Results of the coupled simulation will be compared and verified against experimental data of the same available via General Motors (GM) Department of Energy (DOE) project.« less
Sanchez Sorzano, Carlos Oscar; Alvarez-Cabrera, Ana Lucia; Kazemi, Mohsen; Carazo, Jose María; Jonić, Slavica
2016-04-26
Single-particle electron microscopy (EM) has been shown to be very powerful for studying structures and associated conformational changes of macromolecular complexes. In the context of analyzing conformational changes of complexes, distinct EM density maps obtained by image analysis and three-dimensional (3D) reconstruction are usually analyzed in 3D for interpretation of structural differences. However, graphic visualization of these differences based on a quantitative analysis of elastic transformations (deformations) among density maps has not been done yet due to a lack of appropriate methods. Here, we present an approach that allows such visualization. This approach is based on statistical analysis of distances among elastically aligned pairs of EM maps (one map is deformed to fit the other map), and results in visualizing EM maps as points in a lower-dimensional distance space. The distances among points in the new space can be analyzed in terms of clusters or trajectories of points related to potential conformational changes. The results of the method are shown with synthetic and experimental EM maps at different resolutions. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.
The worldwide Protein Data Bank (wwPDB): ensuring a single, uniform archive of PDB data
Berman, Helen; Henrick, Kim; Nakamura, Haruki; Markley, John L.
2007-01-01
The worldwide Protein Data Bank (wwPDB) is the international collaboration that manages the deposition, processing and distribution of the PDB archive. The online PDB archive is a repository for the coordinates and related information for more than 38 000 structures, including proteins, nucleic acids and large macromolecular complexes that have been determined using X-ray crystallography, NMR and electron microscopy techniques. The founding members of the wwPDB are RCSB PDB (USA), MSD-EBI (Europe) and PDBj (Japan) [H.M. Berman, K. Henrick and H. Nakamura (2003) Nature Struct. Biol., 10, 980]. The BMRB group (USA) joined the wwPDB in 2006. The mission of the wwPDB is to maintain a single archive of macromolecular structural data that are freely and publicly available to the global community. Additionally, the wwPDB provides a variety of services to a broad community of users. The wwPDB website at provides information about services provided by the individual member organizations and about projects undertaken by the wwPDB. PMID:17142228
Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro
2015-04-05
The generalized Born model in the Onufriev, Bashford, and Case (Onufriev et al., Proteins: Struct Funct Genet 2004, 55, 383) implementation has emerged as one of the best compromises between accuracy and speed of computation. For simulations of nucleic acids, however, a number of issues should be addressed: (1) the generalized Born model is based on a linear model and the linearization of the reference Poisson-Boltmann equation may be questioned for highly charged systems as nucleic acids; (2) although much attention has been given to potentials, solvation forces could be much less sensitive to linearization than the potentials; and (3) the accuracy of the Onufriev-Bashford-Case (OBC) model for nucleic acids depends on fine tuning of parameters. Here, we show that the linearization of the Poisson Boltzmann equation has mild effects on computed forces, and that with optimal choice of the OBC model parameters, solvation forces, essential for molecular dynamics simulations, agree well with those computed using the reference Poisson-Boltzmann model. © 2015 Wiley Periodicals, Inc.
Prediction of protein subcellular locations by GO-FunD-PseAA predictor.
Chou, Kuo-Chen; Cai, Yu-Dong
2004-08-06
The localization of a protein in a cell is closely correlated with its biological function. With the explosion of protein sequences entering into DataBanks, it is highly desired to develop an automated method that can fast identify their subcellular location. This will expedite the annotation process, providing timely useful information for both basic research and industrial application. In view of this, a powerful predictor has been developed by hybridizing the gene ontology approach [Nat. Genet. 25 (2000) 25], functional domain composition approach [J. Biol. Chem. 277 (2002) 45765], and the pseudo-amino acid composition approach [Proteins Struct. Funct. Genet. 43 (2001) 246; Erratum: ibid. 44 (2001) 60]. As a showcase, the recently constructed dataset [Bioinformatics 19 (2003) 1656] was used for demonstration. The dataset contains 7589 proteins classified into 12 subcellular locations: chloroplast, cytoplasmic, cytoskeleton, endoplasmic reticulum, extracellular, Golgi apparatus, lysosomal, mitochondrial, nuclear, peroxisomal, plasma membrane, and vacuolar. The overall success rate of prediction obtained by the jackknife cross-validation was 92%. This is so far the highest success rate performed on this dataset by following an objective and rigorous cross-validation procedure.
Thermomechanical Analysis of Shape-Memory Composite Tape Spring
NASA Astrophysics Data System (ADS)
Yang, H.; Wang, L. Y.
2013-06-01
Intelligent materials and structures have been extensively applied for satellite designs in order to minimize the mass and reduce the cost in the launch of the spacecraft. Elastic memory composites (EMCs) have the ability of high-strain packaging and shape-memory effect, but increase the parts and total weight due to the additional heating system. Shape-memory sandwich structures Li and Wang (J. Intell. Mater. Syst. Struct. 22(14), 1605-1612, 2011) can overcome such disadvantage by using the metal skin acting as the heating element. However, the high strain in the micro-buckled metal skin decreases the deployment efficiency. This paper aims to present an insight into the folding and deployment behaviors of shape-memory composite (SMC) tape springs. A thermomechanical process was analyzed, including the packaging deformation at an elevated temperature, shape frozen at the low temperature and shape recovery after reheating. The result shows that SMC tape springs can significantly decrease the strain concentration in the metal skin, as well as exhibiting excellent shape frozen and recovery behaviors. Additionally, possible failure modes of SMC tape springs were also analyzed.
NASA Astrophysics Data System (ADS)
Solana, J. R.; Akhouri, B. P.
2018-07-01
A perturbation theory for square-well chain fluids is developed within the scheme of the (generalised) Wertheim thermodynamic perturbation theory. The theory is based on the Pavlyukhin parametrisations [Y. T. Pavlyukhin, J. Struct. Chem. 53, 476 (2012)] of their simulation data for the first four perturbation terms in the high temperature expansion of the Helmholtz free energy of square-well monomer fluids combined with a second-order perturbation theory for the contact value of the radial distribution function of the square-well monomer fluid that enters into bonding contribution. To obtain the latter perturbation terms, we have performed computer simulations in the hard-sphere reference system. The importance of the perturbation terms beyond the second-order one for the monomer fluid and of the approximations of different orders in the bonding contribution for the chain fluids in the predicted equation of state, excess energy and liquid-vapour coexistence densities is analysed.
Latent interaction effects in the theory of planned behaviour applied to quitting smoking.
Hukkelberg, Silje Sommer; Hagtvet, Knut A; Kovac, Velibor Bobo
2014-02-01
This study applies three latent interaction models in the theory of planned behaviour (TPB; Ajzen, 1988, Attitudes, personality, and behavior. Homewood, IL: Dorsey Press; Ajzen, 1991, Organ. Behav. Hum. Decis. Process., 50, 179) to quitting smoking: (1) attitude × perceived behavioural control on intention; (2) subjective norms (SN) × attitude on intention; and (3) perceived behavioural control × intention on quitting behaviour. The data derive from a longitudinal Internet survey of 939 smokers aged 15-74 over a period of 4 months. Latent interaction effects were estimated using the double-mean-centred unconstrained approach (Lin et al., 2010, Struct. Equ. Modeling, 17, 374) in LISREL. Attitude × SN and attitude × perceived behavioural control both showed a significant interaction effect on intention. No significant interaction effect was found for perceived behavioural control × intention on quitting. The latent interaction approach is a useful method for investigating specific conditions between TPB components in the context of quitting behaviour. Theoretical and practical implications of the results are discussed. © 2013 The British Psychological Society.
The stress intensity factors for a periodic array of interacting coplanar penny-shaped cracks
Lekesiz, Huseyin; Katsube, Noriko; Rokhlin, Stanislav I.; Seghi, Robert R.
2013-01-01
The effect of crack interactions on stress intensity factors is examined for a periodic array of coplanar penny-shaped cracks. Kachanov’s approximate method for crack interactions (Int. J. Solid. Struct. 1987; 23(1):23–43) is employed to analyze both hexagonal and square crack configurations. In approximating crack interactions, the solution converges when the total truncation number of the cracks is 109. As expected, due to high density packing crack interaction in the hexagonal configuration is stronger than that in the square configuration. Based on the numerical results, convenient fitting equations for quick evaluation of the mode I stress intensity factors are obtained as a function of crack density and angle around the crack edge for both crack configurations. Numerical results for the mode II and III stress intensity factors are presented in the form of contour lines for the case of Poisson’s ratio ν =0.3. Possible errors for these problems due to Kachanov’s approximate method are estimated. Good agreement is observed with the limited number of results available in the literature and obtained by different methods. PMID:27175035
DOE Office of Scientific and Technical Information (OSTI.GOV)
A.I. Drozhdin, N.V. Mokhov and M. Huhtinen
1999-04-13
The effect of possible accidental beam loss in LHC on the IP5 insertion elements and CMS detector is studied via realistic Monte Carlo simulations. Such beam loss could be the consequence of an unsynchronized abort or in worst case an accidental prefire of one of the abort kicker modules. Simulations with the STRUCT code show that this beam losses would take place in the IP5 inner and outer triplets. MARS simulations of the hadronic and electro-magnetic cascades induced in such an event indicate severe heating of the inner triplet quadrupoles. In order to protect the IP5 elements, two methods aremore » proposed: a set of shadow collimators in the outer triplet and a prefired module compensation using a special module charged with an opposite voltage (antikicker). The remnants of the accidental beam loss entering the experimental hall have been used as input for FLUKA simulations in the CMS detector. It is shown that it is vital to take measures to reliably protect the expensive CMS tracker components.« less
Aeroelastic flutter energy harvesters self-polarized by triboelectric effects
NASA Astrophysics Data System (ADS)
Perez, M.; Boisseau, S.; Geisler, M.; Gasnier, P.; Willemin, J.; Despesse, G.; Reboud, J. L.
2018-01-01
This paper presents the performances of several electrostatic flutter energy harvesters tested in a wind tunnel between 0 and 20 m s-1. The main idea is to use the flutter capability of thin flexible films confined between lateral walls to induce simultaneously the capacitance variations and the electrostatic polarization required by the triboelectric/electrostatic conversion. This technology provides thin and flexible devices and solve the electret’s stability issue (Perez et al 2015 Smart Mater. Struct., Perez et al 2015 New Circuits and Systems). Our prototypes (<16 cm2) have a quick startup (from 3 m s-1) and an electrical power-flux density from 0.35 μW cm-2@3 m s-1 (light breeze) to 35 μW cm-2@20 m s-1 (fresh gale). A Maximum Power Point circuit has been developed to efficiently use the power provided by the energy harvesters. The energy harvester combined with its power management circuit has finally been used to supply an 868 MHz wireless sensor node with temperature and acceleration measurements, validating the complete energy harvesting chain.
Sun, Conghao; Xu, Liping; Chen, Xiangping; Qiu, Tianyun; Zhou, Tao
2018-02-01
An eco-friendly and benign process has been investigated for the dissolution of Li, Co, Ni, and Mn from the cathode materials of spent LiNi 1/3 Co 1/3 Mn 1/3 O 2 batteries, using DL-malic acid as the leaching agent in this study. The leaching efficiencies of Li, Co, Ni, and Mn can reach about 98.9%, 94.3%, 95.1%, and 96.4%, respectively, under the leaching conditions of DL-malic acid concentration of 1.2 M, hydrogen peroxide content of 1.5 vol.%, solid-to-liquid ratio of 40 g l -1 , leaching temperature of 80°C, and leaching time of 30 min. In addition, the leaching kinetic was investigated based on the shrinking model and the results reveal that the leaching reaction is controlled by chemical reactions within 10 min with activation energies (Ea) of 21.3 kJ·mol -1 , 30.4 kJ·mol -1 , 27.9 kJ·mol -1 , and 26.2 kJ·mol -1 for Li, Co, Ni, and Mn, respectively. Diffusion process becomes the controlled step with a prolonged leaching time from 15 to 30 min, and the activation energies (Ea) are 20.2 kJ·mol -1 , 28.9 kJ·mol -1 , 26.3 kJ·mol -1 , and 25.0 kJ·mol -1 for Li, Co, Ni, and Mn, respectively. This hydrometallurgical route was found to be effective and environmentally friendly for leaching metals from spent lithium batteries.
Tang, Zhibin; Li, Chun; Chen, Zhiwei
2015-03-01
To explore the effect of baicalein on the proliferation and invasion of osteosarcoma cells and its related mechanism. Osteosarcoma MG-63 cells that were cultured in vitro were respectively treated with 20 μL culture medium (control group), dehydrated alcohol (0 μmol/L baicalein group), 100 and 200 μmol/L baicalein solution for 48 hours. Cell proliferation was analyzed by MTT assay. The cell invasion ability was detected using Transwell(TM) invasion assay. The expression of ezrin mRNA was examined by real-time quantitative PCR. The expressions of ezrin protein and p-ezrin protein were measured using Western blotting. Apoptosis index (AI) was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The inhibitory rates of cell proliferation significantly increased in 100 and 200 μmol/L baicalein groups as compared with 0 μmol/L baicalein group. Moreover, that was higher in 200 μmol/L baicalein group than in 100 μmol/L baicalein group. In comparison with control and 0 μmol/L baicalein groups, the mean cell numbers of permeated membrane and levels of ezrin mRNA, ezrin protein and p-ezrin protein gradually decreased, but AI was gradually elevated with the increase of baicalein concentrations, whereas there was no significant difference in these indicators between 0 μmol/L baicalein group and control group. Baicalein can inhibit the proliferation and invasion of osteosarcoma MG-63 cells. The mechanism may be associated with the inhibited expression and activity of ezrin protein and the promoted tumor cell apoptosis.
Borowczyk, Kamila; Wyszczelska-Rokiel, Monika; Kubalczyk, Paweł; Głowacki, Rafał
2015-02-15
In this paper, we describe a simple and robust HPLC based method for determination of total low- and high-molecular-mass thiols, protein S-linked thiols and reduced albumin in plasma. The method is based on derivatization of analytes with 2-chloro-1-methylquinolinium tetrafluoroborate, separation and quantification by reversed-phase liquid chromatography followed by UV detection. Disulfides were converted to their thiol counterparts by reductive cleavage with tris(2-carboxyethyl)phosphine. Linearity in detector response for total thiols was observed over the range of 1-40 μmol L(-1) for Hcy and glutathione (GSH), 5-100 μmol L(-1) for Cys-Gly, 20-300 μmol L(-1) for Cys and 3.1-37.5 μmol L(-1) (0.2-2.4gL(-1)) for human serum albumin (HSA). For the protein S-bound forms these values were as follows: 0.5-30 μmol L(-1) for Hcy and GSH, 2.5-60 μmol L(-1) for Cys-Gly and 5-200 μmol L(-1) for Cys. The LOQs for total HSA, Cys, Hcy, Cys-Gly and GSH were 0.5, 0.2, 0.4, 0.3 and 0.4 μmol L(-1), respectively. The estimated validation parameters for all analytes are more than sufficient to allow the analytical method to be used for monitoring of the total and protein bound thiols as well as redox status of HSA in plasma. Copyright © 2015 Elsevier B.V. All rights reserved.
Arfaeinia, Hossein; Nabipour, Iraj; Ostovar, Afshin; Asadgol, Zahra; Abuee, Ehsan; Keshtkar, Mozhgan; Dobaradaran, Sina
2016-05-01
Sediment samples from the coastal area of Asaluyeh harbor were collected during autumn and spring 2015. The acid-volatile sulfide (AVS) and simultaneously extracted metals (SEMs) were measured to assess the sediment quality and potential ecological risks. The average concentrations (and relative standard deviation (RSD)) of AVS in the industrial sediments were 12.32 μmol/g (36.91) and 6.34 μmol/g (80.05) in autumn and spring, respectively, while in the urban area, these values were 0.44 μmol/g (123.50) and 0.31 μmol/g (160.0) in autumn and spring, respectively. The average concentrations of SEM (and RSD) in the industrial sediments were 15.02 μmol/g (14.38) and 12.34 μmol/g (20.65) in autumn and spring, respectively, while in the urban area, these values were 1.10 μmol/g (43.03) and 1.06 μmol/g (55.59) in autumn and spring, respectively. Zn was the predominant component (34.25-86.24 %) of SEM, while the corresponding value for Cd, much more toxic ingredient, was less than 1 %. Some of the coastal sediments in the harbor of Asaluyeh (20 and 47 % in autumn and spring, respectively) had expected adverse biological effects based on the suggested criterion by United States Environmental Protection Agency (USEPA), while most stations (80 and 53 % in autumn and spring, respectively) had uncertain adverse effects.
Cheng, Lan; Gauss, Jürgen; Ruscic, Branko; ...
2017-01-12
Benchmark scalar-relativistic coupled-cluster calculations for dissociation energies of the 20 diatomic molecules containing 3d transition metals in the 3dMLBE20 database ( J. Chem. Theory Comput. 2015, 11, 2036) are reported in this paper. Electron correlation and basis set effects are systematically studied. The agreement between theory and experiment is in general satisfactory. For a subset of 16 molecules, the standard deviation between computational and experimental values is 9 kJ/mol with the maximum deviation being 15 kJ/mol. The discrepancies between theory and experiment remain substantial (more than 20 kJ/mol) for VH, CrH, CoH, and FeH. To explore the source of themore » latter discrepancies, the analysis used to determine the experimental dissociation energies for VH and CrH is revisited. It is shown that, if improved values are used for the heterolytic C–H dissociation energies of di- and trimethylamine involved in the experimental determination, the experimental values for the dissociation energies of VH and CrH are increased by 18 kJ/mol, such that D 0(VH) = 223 ± 7 kJ/mol and D 0(CrH) = 204 ± 7 kJ/mol (or D e(VH) = 233 ± 7 kJ/mol and D e(CrH) = 214 ± 7 kJ/mol). Finally, the new experimental values agree quite well with the calculated values, showing the consistency of the computation and the measured reaction thresholds.« less
Effect of gingerol on colonic motility via inhibition of calcium channel currents in rats.
Cai, Zheng-Xu; Tang, Xu-Dong; Wang, Feng-Yun; Duan, Zhi-Jun; Li, Yu-Chun; Qiu, Juan-Juan; Guo, Hui-Shu
2015-12-28
To investigate the effect of gingerol on colonic motility and the action of L-type calcium channel currents in this process. The distal colon was cut along the mesenteric border and cleaned with Ca(2+)-free physiological saline solution. Muscle strips were removed and placed in Ca(2+)-free physiological saline solution, which was oxygenated continuously. Longitudinal smooth muscle samples were prepared by cutting along the muscle strips and were then placed in a chamber. Mechanical contractile activities of isolated colonic segments in rats were recorded by a 4-channel physiograph. Colon smooth muscle cells were dissociated by enzymatic digestion. L-type calcium currents were recorded using the conventional whole-cell patch-clamp technique. Gingerol inhibited the spontaneous contraction of colonic longitudinal smooth muscle in a dose-dependent manner with inhibition percentages of 13.3% ± 4.1%, 43.4% ± 3.9%, 78.2% ± 3.6% and 80.5% ± 4.5% at 25 μmol/L, 50 μmol/L, 75 μmol/L and 100 μmol/L, respectively (P < 0.01). Nifedipine, an L-type calcium channel blocker, diminished the inhibition of colonic motility by gingerol. Gingerol inhibited L-type calcium channel currents in colonic longitudinal myocytes of rats. At a 75 μmol/L concentration of gingerol, the percentage of gingerol-induced inhibition was diminished by nifedipine from 77.1% ± 4.2% to 42.6% ± 3.6% (P < 0.01). Gingerol suppressed IBa in a dose-dependent manner, and the inhibition rates were 22.7% ± 2.38%, 35.77% ± 3.14%, 49.78% ± 3.48% and 53.78% ± 4.16% of control at 0 mV, respectively, at concentrations of 25 μmol/L, 50 μmol/L, 75 μmol/L and 100 μmol/L (P < 0.01). The steady-state activation curve was shifted to the right by treatment with gingerol. The value of half activation was -14.23 ± 1.12 mV in the control group and -10.56 ± 1.04 mV in the 75 μmol/L group (P < 0.05) with slope factors, Ks, of 7.16 ± 0.84 and 7.02 ± 0.93 (P < 0.05) in the control and 75 μmol/L groups, respectively. However, the steady-state inactivation curve was not changed, with a half-inactivation voltage, 0.5 V, of -27.43 ± 1.26 mV in the control group and -26.56 ± 1.53 mV in the 75 μmol/L gingerol group (P > 0.05), and a slope factor, K, of 13.24 ± 1.62 in the control group and 13.45 ± 1.68 (P > 0.05) in the 75 μmol/L gingerol group. Gingerol inhibits colonic motility by preventing Ca(2+) influx through L-type calcium channels.
Effect of gingerol on colonic motility via inhibition of calcium channel currents in rats
Cai, Zheng-Xu; Tang, Xu-Dong; Wang, Feng-Yun; Duan, Zhi-Jun; Li, Yu-Chun; Qiu, Juan-Juan; Guo, Hui-Shu
2015-01-01
AIM: To investigate the effect of gingerol on colonic motility and the action of L-type calcium channel currents in this process. METHODS: The distal colon was cut along the mesenteric border and cleaned with Ca2+-free physiological saline solution. Muscle strips were removed and placed in Ca2+-free physiological saline solution, which was oxygenated continuously. Longitudinal smooth muscle samples were prepared by cutting along the muscle strips and were then placed in a chamber. Mechanical contractile activities of isolated colonic segments in rats were recorded by a 4-channel physiograph. Colon smooth muscle cells were dissociated by enzymatic digestion. L-type calcium currents were recorded using the conventional whole-cell patch-clamp technique. RESULTS: Gingerol inhibited the spontaneous contraction of colonic longitudinal smooth muscle in a dose-dependent manner with inhibition percentages of 13.3% ± 4.1%, 43.4% ± 3.9%, 78.2% ± 3.6% and 80.5% ± 4.5% at 25 μmol/L, 50 μmol/L, 75 μmol/L and 100 μmol/L, respectively (P < 0.01). Nifedipine, an L-type calcium channel blocker, diminished the inhibition of colonic motility by gingerol. Gingerol inhibited L-type calcium channel currents in colonic longitudinal myocytes of rats. At a 75 μmol/L concentration of gingerol, the percentage of gingerol-induced inhibition was diminished by nifedipine from 77.1% ± 4.2% to 42.6% ± 3.6% (P < 0.01). Gingerol suppressed IBa in a dose-dependent manner, and the inhibition rates were 22.7% ± 2.38%, 35.77% ± 3.14%, 49.78% ± 3.48% and 53.78% ± 4.16% of control at 0 mV, respectively, at concentrations of 25 μmol/L, 50 μmol/L, 75 μmol/L and 100 μmol/L (P < 0.01). The steady-state activation curve was shifted to the right by treatment with gingerol. The value of half activation was -14.23 ± 1.12 mV in the control group and -10.56 ± 1.04 mV in the 75 μmol/L group (P < 0.05) with slope factors, Ks, of 7.16 ± 0.84 and 7.02 ± 0.93 (P < 0.05) in the control and 75 μmol/L groups, respectively. However, the steady-state inactivation curve was not changed, with a half-inactivation voltage, 0.5 V, of -27.43 ± 1.26 mV in the control group and -26.56 ± 1.53 mV in the 75 μmol/L gingerol group (P > 0.05), and a slope factor, K, of 13.24 ± 1.62 in the control group and 13.45 ± 1.68 (P > 0.05) in the 75 μmol/L gingerol group. CONCLUSION: Gingerol inhibits colonic motility by preventing Ca2+ influx through L-type calcium channels. PMID:26730157
40 CFR 1065.750 - Analytical gases.
Code of Federal Regulations, 2010 CFR
2010-07-01
... O2 concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen... concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen. (3) Use the....41) mol/mol, balance He, and a stated total hydrocarbon concentration of 0.05 µmol/mol or less. (ii...
40 CFR 1065.750 - Analytical gases.
Code of Federal Regulations, 2012 CFR
2012-07-01
... O2 concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen... concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen. (3) Use the....41) mol/mol, balance He, and a stated total hydrocarbon concentration of 0.05 µmol/mol or less. (ii...
40 CFR 1065.750 - Analytical gases.
Code of Federal Regulations, 2013 CFR
2013-07-01
... O2 concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen... concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen. (3) Use the....41) mol/mol, balance He, and a stated total hydrocarbon concentration of 0.05 µmol/mol or less. (ii...
40 CFR 1065.750 - Analytical gases.
Code of Federal Regulations, 2011 CFR
2011-07-01
... O2 concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen... concentration in the exhaust sample is zero, we recommend using a balance gas of purified nitrogen. (3) Use the....41) mol/mol, balance He, and a stated total hydrocarbon concentration of 0.05 µmol/mol or less. (ii...
USDA-ARS?s Scientific Manuscript database
Hydrophilic poly (vinyl alcohol-co-ethylene) (PVA-co-PE) copolymers with 27 mol %, 32 mol % and 44 mol % ethylene were functionalized by melt radical graft copolymerization with 2,4-diamino-6-diallylamino-1,3,5-triazine (NDAM) using reactive extrusion. This functionalization imparts antibacterial pr...
Enhanced hydrogen production from glucose using ldh- and frd-inactivated Escherichia coli strains.
Yoshida, Akihito; Nishimura, Taku; Kawaguchi, Hideo; Inui, Masayuki; Yukawa, Hideaki
2006-11-01
We improved the hydrogen yield from glucose using a genetically modified Escherichia coli. E. coli strain SR15 (DeltaldhA, DeltafrdBC), in which glucose metabolism was directed to pyruvate formate lyase (PFL), was constructed. The hydrogen yield of wild-type strain of 1.08 mol/mol glucose, was enhanced to 1.82 mol/mol glucose in strain SR15. This figure is greater than 90 % of the theoretical hydrogen yield of facultative anaerobes (2.0 mol/mol glucose). Moreover, the specific hydrogen production rate of strain SR15 (13.4 mmol h(-1) g(-1) dry cell) was 1.4-fold higher than that of wild-type strain. In addition, the volumetric hydrogen production rate increased using the process where cells behaved as an effective catalyst. At 94.3 g dry cell/l, a productivity of 793 mmol h(-1) l(-1) (20.2 l h(-1) l(-1) at 37 degrees C) was achieved using SR15. The reported productivity substantially surpasses that of conventional biological hydrogen production processes and can be a trigger for practical applications.
Thermodynamic and kinetic analyses of curcumin and bovine serum albumin binding.
Hudson, Eliara Acipreste; de Paula, Hauster Maximiler Campos; Ferreira, Guilherme Max Dias; Ferreira, Gabriel Max Dias; Hespanhol, Maria do Carmo; da Silva, Luis Henrique Mendes; Pires, Ana Clarissa Dos S
2018-03-01
Bovine serum albumin (BSA)/curcumin binding and dye photodegradation stability were evaluated. BSA/curcumin complex showed 1:1 stoichiometry, but the thermodynamic binding parameters depended on the technique used and BSA conformation. The binding constant was of the order of 10 5 L·mol -1 by fluorescence and microcalorimetric, and 10 3 and 10 4 L·mol -1 by surface plasmon resonance (steady-state equilibrium and kinetic experiments, respectively). For native BSA/curcumin, fluorescence indicated an enthalpic and entropic driven process based on the standard enthalpy change (ΔH ○ F =-8.67kJ·mol -1 ), while microcalorimetry showed an entropic driven binding process (ΔH ○ cal =29.11kJ·mol -1 ). For the unfolded BSA/curcumin complex, it was found thatp ΔH ○ F =-16.12kJ·mol -1 and ΔH ○ cal =-42.63kJ·mol -1 . BSA (mainly native) increased the curcumin photodegradation stability. This work proved the importance of using different techniques to characterize the protein-ligand binding. Copyright © 2017 Elsevier Ltd. All rights reserved.
Methyl (2Z)-2-bromomethyl-3-(3-chlorophenyl)prop-2-enoate
Swaminathan, K.; Sethusankar, K.; Selvakumar, Raman; Bakthadoss, Manickam
2013-01-01
There are two independent molecules (A and B) in the asymmetric unit of the title compound C11H10BrClO2, which represents the Z isomer. The methylacrylate moieties are essentially planar, within 0.084 (2) and 0.027 (5) Å in molecules A and B, respectively. The benzene ring makes dihedral angles of 13.17 (7) and 27.89 (9)° with the methylacrylate moiety in molecules A and B, respectively. The methylbromide moiety is almost orthogonal to the benzene ring, making dihedral angles of 81.46 (16)° in molecule A and 79.61 (16)° in molecule B. The methylacrylate moiety exhibits an extended trans conformation in both molecules. In the crystal, pairs of C—H⋯O hydrogen bonds result in the formation of quasi-centrosymmetric R 2 2(14) AB dimers. PMID:23795037
Ab initio calculation of infrared intensities for hydrogen peroxide
NASA Technical Reports Server (NTRS)
Rogers, J. D.; Hillman, J. J.
1982-01-01
Results of an ab initio SCF quantum mechanical study are used to derive estimates for the infrared intensities of the fundamental vibrations of hydrogen peroxide. Atomic polar tensors (APTs) were calculated on the basis of a 4-31G basis set, and used to derive absolute intensities for the vibrational transitions. Comparison of the APTs calculated for H2O2 with those previously obtained for H2O and CH3OH, and of the absolute intensities derived from the H2O2 APTs with those derived from APTs transferred from H2O and CH3OH, reveals the sets of values to differ by no more than a factor of two, supporting the validity of the theoretical calculation. Values of the infrared intensities obtained correspond to A1 = 14.5 km/mol, A2 = 0.91 km/mol, A3 = 0.058 km/mol, A4 = 123 km/mol, A5 = 46.2 km/mol, and A6 = 101 km/mol. Charge, charge flux and overlap contributions to the dipole moment derivatives are also computed.
Ab initio calculation of infrared intensities for hydrogen peroxide
NASA Astrophysics Data System (ADS)
Rogers, J. D.; Hillman, J. J.
1982-04-01
Results of an ab initio SCF quantum mechanical study are used to derive estimates for the infrared intensities of the fundamental vibrations of hydrogen peroxide. Atomic polar tensors (APTs) were calculated on the basis of a 4-31G basis set, and used to derive absolute intensities for the vibrational transitions. Comparison of the APTs calculated for H2O2 with those previously obtained for H2O and CH3OH, and of the absolute intensities derived from the H2O2 APTs with those derived from APTs transferred from H2O and CH3OH, reveals the sets of values to differ by no more than a factor of two, supporting the validity of the theoretical calculation. Values of the infrared intensities obtained correspond to A1 = 14.5 km/mol, A2 = 0.91 km/mol, A3 = 0.058 km/mol, A4 = 123 km/mol, A5 = 46.2 km/mol, and A6 = 101 km/mol. Charge, charge flux and overlap contributions to the dipole moment derivatives are also computed.
N-(1-Allyl-1H-indazol-5-yl)-4-methoxybenzenesulfonamide hemihydrate
Chicha, Hakima; Rakib, El Mostapha; Geffken, Detlef; Saadi, Mohamed; El Ammari, Lahcen
2013-01-01
In the title compound, C17H17N3O3 .0.5H2O, the indazole system makes a dihedral angle of 46.19 (8)° with the plane through the benzene ring and is nearly perpendicular to the allyl group, as indicated by the dihedral angle of 81.2 (3)°. In the crystal, the water molecule, disordered over two sites related by an inversion center, forms O—H⋯N bridges between indazole N atoms of two sulfonamide molecules. It is also connected via N—H⋯O interaction to the third sulfonamide molecule; however, due to the water molecule disorder, only every second molecule of sulfonamide participates in this interaction. This missing interaction results in a slight disorder of the sulfonamide S,O and N atoms which are split over two sites with half occupancy. With the help of C–H⋯O hydrogen bonds, the molecules are further connected into a three-dimensional network. PMID:24098264
Positron annihilation study on ZnO-based scintillating glasses
NASA Astrophysics Data System (ADS)
Nie, Jiaxiang; Yu, Runsheng; Wang, Baoyi; Ou, Yuwen; Zhong, Yurong; Xia, Fang; Chen, Guorong
2009-04-01
Positron lifetime of ZnO-based scintillating glasses (55 - x)SiO 2-45ZnO- xBaF 2 ( x = 5, 10, 15 mol%) were measured with a conventional fast-fast spectrometer. Three positron lifetime components τ1, τ 2, and τ3 are ˜0.23 ns, ˜0.45 ns, and ˜1.6 ns, respectively. All the three positron lifetime components first increase with increasing BaF 2 concentration from 5 mol% to 10 mol%, then decreases as BaF 2 further increases to 15 mol%. The result suggests that the glass sample with 10 mol% BaF 2 contains the highest defect density, and is in excellent agreement with glass chemistry, glass density, thermal properties, and calculated crystallinity. Therefore, positron annihilation lifetime measurement is an effective tool for analyzing defects in ZnO-based scintillating glasses.
Enthalpies of melting of LnSF compounds (Ln = La, Ce, Pr, Nd, Sm)
NASA Astrophysics Data System (ADS)
Andreev, P. O.; Mikhalkina, O. G.; Andreev, O. V.; Elyshev, A. V.
2015-05-01
The melting temperatures and enthalpies of such congruently melting compounds as LaSF ( T m = 1713 ± 7 K, Δ H = 45.7 ± 4.6 kJ/mol), CeSF ( T m = 1683 ± 7 K, Δ H = 40.7 ± 4.1 kJ/mol), PrSF ( T m = 1661 ± 7 K, Δ H = 39.7 ± 4.0 kJ/mol), NdSF ( T m = 1654 ± 7 K, Δ H = 40.2 ± 4.0 kJ/mol), and SmSF ( T m = 1587 ± 7 K, Δ H = 36.1 ± 3.6 kJ/mol) are determined via synchronous thermal analysis. The tetrad effect is evident in the change of the melting temperatures and enthalpies of LnSF compounds (Ln = La, Ce, Pr, Nd, Sm) depending on r(Ln3+).
Structural events in the photocycle of green fluorescent protein.
van Thor, Jasper J; Zanetti, Giulia; Ronayne, Kate L; Towrie, Michael
2005-08-25
Picosecond time-resolved mid-infrared absorption changes of the wild type green fluorescent protein from Aequorea victoria are reported on structural events during the photocycle. Concomitant with rapid H/D transfer following excitation of the neutral A state at 400 nm, a transient signal at 1721/1711 cm(-1) (H/D) developed belonging to protonated glutamate 222, which was definitively assigned using the E222D mutant from the altered proton-transfer kinetics to aspartate in addition to the altered band position and intensity in the spectra. A transient at 1697 cm(-1), assigned to a structural perturbation of glutamine 69, had a H/D kinetic isotope effect of >32, showing the conformational dynamics to be sensitive to the active site H/D vibrations. The kinetic data up to 2 ns after excitation in the 1250-1800 cm(-1) region in D2O provided 10 and 75 ps time constants for the excited-state deuteron transfer and the associated A1* - A1 and A2* - A2 difference spectra and showed the radiative intermediate I state vibrations and the transient accumulation of the long-lived ground-state intermediate I2. Assignments of chromophore modes for the A1, A2, and I2 ground states are proposed on the basis of published model compound studies (Esposito, A. P.; Schellenberg, P.; Parson, W. W.; Reid, P. J. J. Mol. Struct. 2001, 569, 25 and He, X.; Bell, A. F.; Tonge, P. J. J. Phys. Chem. B 2002, 106, 6056). Tentative assignments for the singlet-state intermediates A1*, A2*, and I* are discussed. An unexpected and unassigned band that may be a C=C chromophore vibration was observed in the ground state (1665 cm(-1)) as well as in all photocycle intermediates. Optical dumping of the transient I population was achieved using an additional 532 nm pulse and the directly obtained I2 - I* difference spectrum was highly similar to the I2 - I* photocycle spectrum. The pump-dump-probe spectrum differed from the pump-probe photocycle difference spectrum with respect to the intensity of the phenol 1 mode at 1578 cm(-1), suggesting stronger delocalization of the negative charge onto the phenolic ring of the anionic chromophore in the dumped I2 state. Indication for structural heterogeneity of the chromophore, Glu 222, and the chromophore environment was found in the two parallel proton-transfer reactions and their distinct associated ground- and intermediate-state vibrations. Vibrational spectral markers at 1695 cm(-1) assigned to Gln 69, at 1631 cm(-1) belonging to a C=C mode, and at 1354 cm(-1) belonging to a phenolate vibration further indicated the I2 and I* states to be unrelaxed.
Cui, Yao-Ming; Wang, Jing; Lu, Wei; Zhang, Hai-Jun; Wu, Shu-Geng; Qi, Guang-Hai
2018-04-11
The objective of this study was to evaluate the effects of dietary supplementation with Moringa oleifera leaf (MOL) on performance, carcass characteristics, meat quality, and oxidative stability of breast muscle in broilers. A total of 720 1-d-old male Arbor Acres birds were randomly divided into 6 dietary groups, which were fed a basal diet supplemented with 0, 1, 2, 5, 10, and 15% MOL, respectively. Each group had 6 replicates of 20 birds each. The feeding trial lasted for 42 d. The results showed dietary MOL supplementation linearly and quadratically decreased body weight and average daily gain (P < 0.01), and increased feed conversion ratio (P < 0.001). Abdominal fat decreased linearly and quadratically in response to the supplementation of MOL in diets, both on d 21 and 42 (P < 0.001). In breast muscle, dietary supplementation with MOL quadratically increased the contents of C18:2, C18:3n-3, C20:4, polyunsaturated fatty acids (PUFA), n-3 PUFA, n-6 PUFA (P < 0.01), and decreased thrombogenic index (TI; P = 0.019). Dietary inclusion of MOL improved meat color, evidenced by quadratically reduced b* (yellowness) values (45 min postmortem, P = 0.001; 24 h postmortem, P = 0.018) and increased a* (redness) values (24 h postmortem, P < 0.001). Besides, diets supplemented with MOL quadratically decreased malondialdehyde (MDA) levels in breast muscle during storage (P < 0.001). Plasma total anti-oxidative capacity, total superoxide dismutase, glutathione peroxidase activities increased quadratically (P < 0.01), whereas MDA decreased quadratically (P < 0.001), in response to dietary MOL supplementation. In summary, MOL could be used as a feed ingredient for broilers to improve PUFA contents, oxidative stability, color of breast muscle, and abdominal fat without adverse effects on growth performance, with an inclusion of 1.56% in the diets.
Guan, Zhong; Li, Huai-Fang; Guo, Li-Li; Yang, Xiang
2015-08-01
This study aimed to investigate the effects of three different antioxidants, namely vitamin C, vitamin E, and molecular hydrogen, on cytotrophoblasts in vitro. Two trophoblast cell lines, JAR and JEG-3, were exposed to different concentrations of vitamin C (0, 25, 50, 100, 500, 1,000, 5,000 μmol/L), vitamin E (0, 25, 50, 100, 500, 1,000, 5,000 μmol/L), and molecular hydrogen (0, 25, 50, 100, 500 μmol/L) for 48 h. The cell viability was detected using the MTS assay. The secretion of human chorionic gonadotropin (hCG) and the tumor necrosis factor-α (TNF-α) were assessed and the expression of TNF-α mRNA was observed by real-time RT-PCR. Cell viability was significantly suppressed by 500 μmol/L vitamins C and E (P < 0.05), but not by 500 μmol/L molecular hydrogen (P > 0.05). The expression of TNF-α was increased by 100 μmol/L vitamin C and 50 μmol/L vitamins E, separately or combined (P < 0.05), but not by molecular hydrogen (0-500 μmol/L), as validated by real-time RT-PCR. But the secretion of hCG was both inhibited by 50-500 μmol/L molecular hydrogen and high levels of vitamin C and E, separately or combined. High levels of antioxidant vitamins C and E may have significant detrimental effects on placental function, as reflected by decreased cell viability and secretion of hCG; and placental immunity, as reflected by increased production of TNF-a. Meanwhile hydrogen showed no such effects on cell proliferation and TNF-α expression, but it could affect the level of hCG, indicating hydrogen as a potential candidate of antioxidant in the management of preeclampsia (PE) should be further studied.
Pathways for the OH + Br2 → HOBr + Br and HOBr + Br → HBr + BrO Reactions.
Wang, Hongyan; Qiu, Yudong; Schaefer, Henry F
2016-02-11
The OH radical reaction with Br2 and the subsequent reaction HOBr + Br are of exceptional importance to atmospheric chemistry and environmental chemistry. The entrance complex, transition state, and exit complex for both reactions have been determined using the coupled-cluster method with single, double, and perturbative triple excitations CCSD(T) with correlation consistent basis sets up to size cc-pV5Z and cc-pV5Z-PP. Coupled cluster effects with full triples (CCSDT) and full quadruples (CCSDTQ) are explicitly investigated. Scalar relativistic effects, spin-orbit coupling, and zero-point vibrational energy corrections are evaluated. The results from the all-electron basis sets are compared with those from the effective core potential (ECP) pseudopotential (PP) basis sets. The results are consistent. The OH + Br2 reaction is predicted to be exothermic 4.1 ± 0.5 kcal/mol, compared to experiment, 3.9 ± 0.2 kcal/mol. The entrance complex HO···BrBr is bound by 2.2 ± 0.2 kcal/mol. The transition state lies similarly well below the reactants OH + Br2. The exit complex HOBr···Br is bound by 2.7 ± 0.6 kcal/mol relative to separated HOBr + Br. The endothermicity of the reaction HOBr + Br → HBr + BrO is 9.6 ± 0.7 kcal/mol, compared with experiment 8.7 ± 0.3 kcal/mol. For the more important reverse (exothermic) HBr + BrO reaction, the entrance complex BrO···HBr is bound by 1.8 ± 0.6 kcal/mol. The barrier for the HBr + BrO reaction is 6.8 ± 0.9 kcal/mol. The exit complex (Br···HOBr) for the HBr + BrO reaction is bound by 1.9 ± 0.2 kcal/mol with respect to the products HOBr + Br.
Mahajanakatti, Arpitha Badarinath; Murthy, Geetha; Sharma, Narasimha; Skariyachan, Sinosh
2014-03-01
Various types of cancer accounts for 10% of total death worldwide which necessitates better therapeutic strategies. Curcumin, a curcuminoid present in Curcuma longa, shown to exhibit antioxidant, anti-inflammatory and anticarcinogenic properties. Present study, we aimed to analyze inhibitory properties of curcumin towards virulent proteins for various cancers by computer aided virtual screening. Based on literature studies, twenty two receptors were selected which have critical virulent functions in various cancer. The binding efficiencies of curcumin towards selected targets were studied by molecular docking. Out of all, curcumin showed best results towards epidermal growth factor (EGF), virulent protein of gastric cancer; glutathione-S-transferase Pi gene (GST-PI), virulent protein for prostate cancer; platelet-derived growth factor alpha (PDGFA), virulent protein for mesothelioma and glioma compared with their natural ligands. The calculated binding energies of their docked conformations with curcumin found to be -7.59 kcal/mol, -7.98 kcal/mol and -7.93 kcal/mol respectively. Further, a comparative study was performed to screen binding efficiency of curcumin with two conventional antitumor agents, litreol and triterpene. Docking studies revealed that calculated binding energies of docked complex of litreol and EGF, GST-PI and PDGFA were found to be -5.08 kcal/mol, -3.69 kcal/mol and -1.86 kcal/mol respectively. The calculated binding energies of triterpene with EGF and PDGFA were found to be -4.02 kcal/mol and -3.11 kcal/mol respectively, whereas GST-PI showed +6.07 kcal/mol, indicate poor binding. The predicted pharmacological features of curcumin found to be better than litreol and triterpene. Our study concluded that curcumin has better interacting properties towards these cancer targets than their normal ligands and conventional antitumor agents. Our data pave insight for designing of curcumin as novel inhibitors against various types of cancer.
Theoretical Study of Spin Crossover in 30 Iron Complexes.
Kepp, Kasper P
2016-03-21
Iron complexes are important spin crossover (SCO) systems with vital roles in oxidative metabolism and promising technological potential. The SCO tendency depends on the free energy balance of high- and low-spin states, which again depends on physical effects such as dispersion, relativistic effects, and vibrational entropy. This work studied 30 different iron SCO systems with experimentally known thermochemical data, using 12 different density functionals. Remarkably general entropy-enthalpy compensation across SCO systems was identified (R = 0.82, p = 0.002) that should be considered in rational SCO design. Iron(II) complexes displayed higher ΔH and ΔS values than iron(III) complexes and also less steep compensation effects. First-coordination sphere ΔS values computed from numerical frequencies reproduce most of the experimental entropy and should thus be included when modeling spin-state changes in inorganic chemistry (R = 0.52, p = 3.4 × 10(-3); standard error in TΔS ≈ 4.4 kJ/mol at 298 K vs 16 kJ/mol of total TΔS on average). Zero-point energies favored high-spin states by 9 kJ/mol on average. Interestingly, dispersion effects are surprisingly large for the SCO process (average: 9 kJ/mol, but up to 33 kJ/mol) and favor the more compact low-spin state. Relativistic effects favor low-spin by ∼9 kJ/mol on average, but up to 24 kJ/mol. B3LYP*, TPSSh, B2PLYP, and PW6B95 performed best for the typical calculation scheme that includes ZPE. However, if relativistic and dispersion effects are included, only B3LYP* remained accurate. On average, high-spin was favored by LYP by 11-15 kJ/mol relative to other correlation functionals, and by 4.2 kJ/mol per 1% HF exchange in hybrids. 13% HF exchange was optimal without dispersion, and 15% was optimal with all effects included for these systems.
NASA Astrophysics Data System (ADS)
Hammer, S.; Konrad, G.; Vermeulen, A. T.; Laurent, O.; Delmotte, M.; Jordan, A.; Hazan, L.; Conil, S.; Levin, I.
2013-05-01
In the course of the ICOS (Integrated Carbon Observation System) Demonstration Experiment a feasibility study on the usefulness of a travelling comparison instrument (TCI) was conducted in order to evaluate continuous atmospheric CO2 and CH4 measurements at two European stations. The aim of the TCI is to independently measure ambient air in parallel to the standard station instrumentation, thus providing a comprehensive comparison that includes the sample intake system, the instrument itself as well as its calibration and data evaluation. Observed differences between the TCI and a gas chromatographic system, which acted as a reference for the TCI, were -0.02 ± 0.08 μmol mol-1 for CO2 and -0.3 ± 2.3 nmol mol-1 for CH4. Over a period of two weeks each, the continuous CO2 and CH4 measurements at two ICOS field stations, Cabauw (CBW), the Netherlands and Houdelaincourt (Observatoire Pérenne de l'Environnement, OPE), France, were compared to co-located TCI measurements. At Cabauw mean differences of 0.21 ± 0.06 μmol mol-1 for CO2 and 0.41 ± 0.50 nmol mol-1 for CH4 were found. For OPE the mean differences were 0.13 ± 0.07 μmol mol-1 for CO2 and 0.44 ± 0.36 nmol mol-1 for CH4. Offsets arising from differences in the working standard calibrations or leakages/contaminations in the drying systems are too small to explain the observed differences. Hence the most likely causes of these observed differences are leakages or contaminations in the intake lines and/or their flushing pumps. For the Cabauw instrument an additional error contribution originates from insufficient flushing of standard gases. Although the TCI is an extensive quality control approach it cannot replace other quality control systems. Thus, a comprehensive quality management strategy for atmospheric monitoring networks is proposed as well.
THE MECHANISM OF ACTION OF COLCHICINE
Wilson, Leslie; Meza, Isaura
1973-01-01
The thermal depolymerization procedure of Stephens (1970. J. Mol. Biol. 47:353) has been employed for solubilization of Strongylocentrotus purpuratus sperm tail outer doublet microtubules with the use of a buffer during solubilization which is of optimal pH and ionic strength for the preservation of colchicine binding activity of chick embryo brain tubulin. Colchicine binding values were corrected for first-order decay during heat solubilization at 50°C (t½ = 5.4 min) and incubation with colchicine at 37°C in the presence of vinblastine sulfate (t½ = 485 min). The colchicine binding properties of heat-solubilized outer doublet tubulin were qualitatively identical with those of other soluble forms of tubulin. The solubilized tubulin (mol wt, 115,000) bound 0.9 ± 0.2 mol of colchicine per mol of tubulin, with a binding constant of 6.3 x 105 liters/mol at 37°C. The colchicine binding reaction was both time and temperature dependent, and the binding of colchicine was prevented in a competitive manner by podophyllotoxin (Ki = 1.3 x 10-6 M). The first-order decay of colchicine binding activity was substantially decreased by the addition of the vinca alkaloids, vinblastine sulfate or vincristine sulfate, thus demonstrating the presence of a vinca alkaloid binding site(s) on the outer doublet tubulin. Tubulin contained within the assembled microtubules did not decay. Intact outer doublet microtubules bound less than 0.001 mol of colchicine per mol of tubulin contained in the microtubules, under conditions where soluble tubulin would have bound 1 mol of colchicine per mol of tubulin (saturating concentration of colchicine, no decay of colchicine binding activity). The presence of colchicine had no effect on the rate of solubilization of outer doublet microtubules during incubation at 37°C. Therefore, the colchicine binding site on tubulin is blocked (not available to bind colchicine) when the tubulin is in the assembled outer doublet microtubules. PMID:4747924
Monoamine Oxidase and Dopamine β-Hydroxylase Inhibitors from the Fruits of Gardenia jasminoides
Kim, Ji Ho; Kim, Gun Hee; Hwang, Keum Hee
2012-01-01
This research was designed to determine what components of Gardenia jasminoides play a major role in inhibiting the enzymes related antidepressant activity of this plant. In our previous research, the ethyl acetate fraction of G. jasminosides fruits inhibited the activities of both monoamine oxidase-A (MAO-A) and monoamine oxidase-B (MAO-B), and oral administration of the ethanolic extract slightly increased serotonin concentrations in the brain tissues of rats and decreased MAO-B activity. In addition, we found through in vitro screening test that the ethyl acetate fraction showed modest inhibitory activity on dopamine-β hydroxylase (DBH). The bioassay-guided fractionation led to the isolation of five bio-active compounds, protocatechuic acid (1), geniposide (2), 6'-O-trans-p-coumaroylgeniposide (3), 3,5-d-ihydroxy-1,7-bis (4-hydroxyphenyl) heptanes (4), and ursolic acid (5), from the ethyl acetate fraction of G. jasminoides fruits. The isolated compounds showed different inhibitory potentials against MAO-A, -B, and DBH. Protocatechuic acid showed potent inhibition against MAO-B (IC50 300 μmol/L) and DBH (334 μmol/L), exhibiting weak MAO-A inhibition (2.41 mmol/L). Two iridoid glycosides, geniposide (223 μmol/L) and 6'-O-trans-p-coumaroylgeniposide (127μmol/L), were selective MAO-B inhibitor. Especially, 6'-O-trans-p-coumaroylgeniposide exhibited more selective MAO-B inhibition than deprenyl, well-known MAO-B inhibitor for the treatment of early-stage Parkinson’s disease. The inhibitory activity of 3,5-di-hydroxy-1,7-bis (4-hydroxyphenyl) heptane was strong for MAO-B (196 μmol/L), modest for MAO-A (400 μmol/L), and weak for DBH (941 μmol/L). Ursolic acid exhibited significant inhibition of DBH (214 μmol/L), weak inhibition of MAO-B (780 μmol/L), and no inhibition against MAO-A. Consequently, G. jasminoides fruits are considerable for development of biofunctional food materials for the combination treatment of depression and neurodegenerative disorders. PMID:24116298
Perlovich, German L; Volkova, Tatyana V; Bauer-Brandl, Annette
2006-10-01
Temperature dependencies of saturated vapor pressure for the monoclinic modification of paracetamol (acetaminophen), acetanilide, and phenacetin (acetophenetidin) were measured and thermodynamic functions of sublimation calculated (paracetamol: DeltaGsub298=60.0 kJ/mol; DeltaHsub298=117.9+/-0.7 kJ/mol; DeltaSsub298=190+/-2 J/mol.K; acetanilide: DeltaGsub298=40.5 kJ/mol; DeltaHsub298=99.8+/-0.8 kJ/mol; DeltaSsub298=197+/-2 J/mol.K; phenacetin: DeltaGsub298=52.3 kJ/mol; DeltaHsub298=121.8+/-0.7 kJ/mol; DeltaSsub298=226+/-2 J/mol.K). Analysis of packing energies based on geometry optimization of molecules in the crystal lattices using diffraction data and the program Dmol3 was carried out. Parameters analyzed were: (a) energetic contribution of van der Waals forces and hydrogen bonding to the total packing energy; (b) contributions of fragments of the molecules to the packing energy. The fraction of hydrogen bond energy in the packing energy increases as: phenacetin (17.5%)
Moyo, Busani; Masika, Patrick J; Muchenje, Voster
2012-04-01
The objective of the study was to determine the effect of supplementing Moringa oleifera leaves (MOL) on growth performance, carcass and non-carcass characteristics of crossbred Xhosa lop-eared goats. A total of 24 castrated goats aged 8 months, with a mean initial weight of 15.1 ± 2.3 kg, were randomly divided into three diet groups with eight goats in each. The duration of the trial was 60 days. All goats received a basal diet of grass hay (GH) ad libitum and wheat bran (200 g/day each). The MOL and sunflower cake (SC) groups were fed additional 200 g of dried M. oleifera leaves and 170 g of SC, respectively. The third group (GH) did not receive any additional ration. The crude protein of MOL (23.75%) and SC (23.27%) were higher (P < 0.05) than that of the GH diet (14.08%). The attained average daily weight gain for goats fed MOL, SC and GH were 103.3, 101.3 and 43.3 g, respectively (P < 0.05). Higher (P < 0.05) feed intakes observed were in SC (491.5 g) and MOL (490.75 g) compared with GH (404.5 g). The hot carcass weight was higher (P < 0.05) for SC (10.48 kg) and MOL (10.34 kg) than for the GH group (8.59 kg). The dressing percentage in SC (55.8%) and MOL (55.1%) were higher (P < 0.05) than that of the GH (52.9%). The growth performance and carcass characteristics of SC and MOL goats were not different. Feeding MOL or SC improved the growth performance and carcass characteristics of goats in an almost similar way, which indicates that M. oleifera could be used as an alternative protein supplement in goats.
Sun, Tao; Liu, Rui; Cao, Yong-xiao
2011-08-01
To investigate the mechanisms underlying the vasorelaxant effect of formononetin, an O-methylated isoflavone, in isolated arteries, and its antihypertensive activity in vivo. Arterial rings of superior mesenteric arteries, renal arteries, cerebral basilar arteries, coronary arteries and abdominal aortas were prepared from SD rats. Isometric tension of the arterial rings was recorded using a myograph system. Arterial pressure was measured using tail-cuff method in spontaneously hypertensive rats. Formononetin (1-300 μmol/L) elicited relaxation in arteries of the five regions that were pre-contracted by KCl (60 mmol/L), U46619 (1 μmol/L) or phenylephrine (10 μmol/L). The formononetin-induced relaxation was reduced by removal of endothelium or by pretreatment with L-NAME (100 μmol/L). Under conditions of endothelium denudation, formononetin (10, 30, and 100 μmol/L) inhibited the contraction induced by KCl and that induced by CaCl(2) in Ca(2+)-free depolarized medium. In the absence of extracellular Ca(2+), formononetin (10, 30, and 100 μmol/L) depressed the constriction caused by phenylephrine (10 μmol/L), but did not inhibit the tonic contraction in response to the addition of CaCl(2) (2 mmol/L). The contraction caused by caffeine (30 mmol/L) was not inhibited by formononetin (100 μmol/L). Formononetin (10 and 100 μmol/L) reduced the change rate of Ca(2+)-fluorescence intensity in response to KCl (50 mmol/L). In spontaneously hypertensive rats, formononetin (5, 10, and 20 mg/kg) slowly lowered the systolic, diastolic and mean arterial pressure. Formononetin causes vasodilatation via two pathways: (1) endothelium-independent pathway, probably due to inhibition of voltage-dependent Ca(2+) channels and intracellular Ca(2+) release; and (2) endothelium-dependent pathway by releasing NO. Both the pathways may contribute to its antihypertensive effect.
SUN, Tao; LIU, Rui; CAO, Yong-xiao
2011-01-01
Aim: To investigate the mechanisms underlying the vasorelaxant effect of formononetin, an O-methylated isoflavone, in isolated arteries, and its antihypertensive activity in vivo. Methods: Arterial rings of superior mesenteric arteries, renal arteries, cerebral basilar arteries, coronary arteries and abdominal aortas were prepared from SD rats. Isometric tension of the arterial rings was recorded using a myograph system. Arterial pressure was measured using tail-cuff method in spontaneously hypertensive rats. Results: Formononetin (1–300 μmol/L) elicited relaxation in arteries of the five regions that were pre-contracted by KCl (60 mmol/L), U46619 (1 μmol/L) or phenylephrine (10 μmol/L). The formononetin-induced relaxation was reduced by removal of endothelium or by pretreatment with L-NAME (100 μmol/L). Under conditions of endothelium denudation, formononetin (10, 30, and 100 μmol/L) inhibited the contraction induced by KCl and that induced by CaCl2 in Ca2+-free depolarized medium. In the absence of extracellular Ca2+, formononetin (10, 30, and 100 μmol/L) depressed the constriction caused by phenylephrine (10 μmol/L), but did not inhibit the tonic contraction in response to the addition of CaCl2 (2 mmol/L). The contraction caused by caffeine (30 mmol/L) was not inhibited by formononetin (100 μmol/L). Formononetin (10 and 100 μmol/L) reduced the change rate of Ca2+-fluorescence intensity in response to KCl (50 mmol/L). In spontaneously hypertensive rats, formononetin (5, 10, and 20 mg/kg) slowly lowered the systolic, diastolic and mean arterial pressure. Conclusion: Formononetin causes vasodilatation via two pathways: (1) endothelium-independent pathway, probably due to inhibition of voltage-dependent Ca2+ channels and intracellular Ca2+ release; and (2) endothelium-dependent pathway by releasing NO. Both the pathways may contribute to its antihypertensive effect. PMID:21818108
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yuhchyau; Pandya, Kishan J.; Feins, Richard
Purpose: We report the toxicity profile and pharmacokinetic data of a schedule-dependent chemoradiation regimen using pulsed low-dose paclitaxel for radiosensitization in a Phase I study for inoperable non-small-cell lung cancer. Methods and Materials: Paclitaxel at escalating doses of 15 mg/m{sup 2}, 20 mg/m{sup 2}, and 25 mg/m{sup 2} were infused on Monday, Wednesday, and Friday with daily chest radiation in cohorts of 6 patients. Daily radiation was delayed for maximal G2/M arrest and apoptotic effect, an observation from preclinical investigations. Plasma paclitaxel concentration was determined by high-performance liquid chromatography. Results: Dose-limiting toxicities included 3 of 18 patients with Grade 3more » pneumonitis and 3 of 18 patients with Grade 3 esophagitis. There was no Grade 4 or 5 pneumonitis or esophagitis. There was also no Grade 3 or 4 neutropenia, thrombocytopenia, anemia or neuropathy. For Dose Levels I (15 mg/m{sup 2}), II (20 mg/m{sup 2}), and III (25 mg/m{sup 2}), the mean peak plasma level was 0.23 {+-} 0.06 {mu}mol/l, 0.32 {+-} 0.05 {mu}mol/l, and 0.52 {+-} 0.14 {mu}mol/l, respectively; AUC was 0.44 {+-} 0.09 {mu}mol/l, 0.61 {+-} 0.1 {mu}mol/l, and 0.96 {+-} 0.23 {mu}mol/l, respectively; and duration of drug concentration >0.05 {mu}mol/l (t > 0.05 {mu}mol/l) was 1.6 {+-} 0.3 h, 1.9 {+-} 0.2 h, and 3.0 {+-} 0.9 h, respectively. Conclusion: Pulsed low-dose paclitaxel chemoradiation is associated with low toxicity. Pharmacokinetic data showed that plasma paclitaxel concentration >0.05 {mu}mol/l for a minimum of 1.6 h was sufficient for effective radiosensitization.« less
Final report of international comparison APMP.QM-S2.2015 of oxygen in nitrogen at 0.2 mol/mol
NASA Astrophysics Data System (ADS)
Aoki, Nobuyuki; Shimosaka, Takuya; Lin, Tsai-Yin; Liu, Hsin-Wang; Huang, Chiung-Kun; Wongjuk, Arnuttachai; Rattanasombat, Soponrat; Sinweeruthai, Ratirat; Uehara, Shinji; Aleksandrov, Vladimir
2017-01-01
This document describes the results of the supplementary comparison for oxygen in nitrogen gas mixture. The nominal amount-of-substance fraction of oxygen is 0.20 mol/mol. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Thermal Conductivity of Alumina-Toughened Zirconia Composites
NASA Technical Reports Server (NTRS)
Bansal, Narottam P.; Zhu, Dong-Ming
2003-01-01
10-mol% yttria-stabilized zirconia (10YSZ)-alumina composites containing 0 to 30 mol% alumina were fabricated by hot pressing at 1500 C in vacuum. Thermal conductivity of the composites, determined at various temperatures using a steady-state laser heat flux technique, increased with increase in alumina content. Composites containing 0, 5, and 10-mol% alumina did not show any change in thermal conductivity with temperature. However, those containing 20 and 30-mol% alumina showed a decrease in thermal conductivity with increase in temperature. The measured values of thermal conductivity were in good agreement with those calculated from simple rule of mixtures.
MOLECULAR GAS AND STAR FORMATION IN NEARBY DISK GALAXIES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leroy, Adam K.; Munoz-Mateos, Juan-Carlos; Walter, Fabian
2013-08-01
We compare molecular gas traced by {sup 12}CO (2-1) maps from the HERACLES survey, with tracers of the recent star formation rate (SFR) across 30 nearby disk galaxies. We demonstrate a first-order linear correspondence between {Sigma}{sub mol} and {Sigma}{sub SFR} but also find important second-order systematic variations in the apparent molecular gas depletion time, {tau}{sub dep}{sup mol}={Sigma}{sub mol}/{Sigma}{sub SFR}. At the 1 kpc common resolution of HERACLES, CO emission correlates closely with many tracers of the recent SFR. Weighting each line of sight equally, using a fixed {alpha}{sub CO} equivalent to the Milky Way value, our data yield a molecularmore » gas depletion time, {tau}{sub dep}{sup mol}={Sigma}{sub mol}/{Sigma}{sub SFR}{approx}2.2 Gyr with 0.3 dex 1{sigma} scatter, in very good agreement with recent literature data. We apply a forward-modeling approach to constrain the power-law index, N, that relates the SFR surface density and the molecular gas surface density, {Sigma}{sub SFR}{proportional_to}{Sigma}{sub mol}{sup N}. We find N = 1 {+-} 0.15 for our full data set with some scatter from galaxy to galaxy. This also agrees with recent work, but we caution that a power-law treatment oversimplifies the topic given that we observe correlations between {tau}{sub dep}{sup mol} and other local and global quantities. The strongest of these are a decreased {tau}{sub dep}{sup mol} in low-mass, low-metallicity galaxies and a correlation of the kpc-scale {tau}{sub dep}{sup mol} with dust-to-gas ratio, D/G. These correlations can be explained by a CO-to-H{sub 2} conversion factor ({alpha}{sub CO}) that depends on dust shielding, and thus D/G, in the theoretically expected way. This is not a unique interpretation, but external evidence of conversion factor variations makes this the most conservative explanation of the strongest observed {tau}{sub dep}{sup mol} trends. After applying a D/G-dependent {alpha}{sub CO}, some weak correlations between {tau}{sub dep}{sup mol} and local conditions persist. In particular, we observe lower {tau}{sub dep}{sup mol} and enhanced CO excitation associated with nuclear gas concentrations in a subset of our targets. These appear to reflect real enhancements in the rate of star formation per unit gas, and although the distribution of {tau}{sub dep} does not appear bimodal in galaxy centers, {tau}{sub dep} does appear multivalued at fixed {Sigma}{sub H2}, supporting the idea of ''disk'' and ''starburst'' modes driven by other environmental parameters.« less
Tomcho, Jeremy C; Tillman, Magdalena R; Znosko, Brent M
2015-09-01
Predicting the secondary structure of RNA is an intermediate in predicting RNA three-dimensional structure. Commonly, determining RNA secondary structure from sequence uses free energy minimization and nearest neighbor parameters. Current algorithms utilize a sequence-independent model to predict free energy contributions of dinucleotide bulges. To determine if a sequence-dependent model would be more accurate, short RNA duplexes containing dinucleotide bulges with different sequences and nearest neighbor combinations were optically melted to derive thermodynamic parameters. These data suggested energy contributions of dinucleotide bulges were sequence-dependent, and a sequence-dependent model was derived. This model assigns free energy penalties based on the identity of nucleotides in the bulge (3.06 kcal/mol for two purines, 2.93 kcal/mol for two pyrimidines, 2.71 kcal/mol for 5'-purine-pyrimidine-3', and 2.41 kcal/mol for 5'-pyrimidine-purine-3'). The predictive model also includes a 0.45 kcal/mol penalty for an A-U pair adjacent to the bulge and a -0.28 kcal/mol bonus for a G-U pair adjacent to the bulge. The new sequence-dependent model results in predicted values within, on average, 0.17 kcal/mol of experimental values, a significant improvement over the sequence-independent model. This model and new experimental values can be incorporated into algorithms that predict RNA stability and secondary structure from sequence.
NASA Astrophysics Data System (ADS)
Liu, Chun Mei; Xu, Chao; Duan, Man Yi
2015-10-01
SnS has potential technical applications, but many of its properties are still not well studied. In this work, the structural, thermodynamic, elastic, and electronic properties of α-SnS have been investigated by the plane wave pseudo-potential density functional theory with the framework of generalised gradient approximation. The calculated pressure-dependent lattice parameters agree well with the available experimental data. Our thermodynamic properties of α-SnS, including heat capacity CP , entropy S, and Gibbs free energy relation of -(GT -H0) curves, show similar growth trends as the experimental data. At T=298.15 K, our CP =52.31 J/mol·K, S=78.93 J/mol·K, and -(GT -H0)=12.03 J/mol all agree very well with experimental data CP =48.77 J/mol·K and 49.25 J/mol·K, S=76.78 J/mol·K, and -(GT -H0)=12.38 J/mol. The elastic constants, together with other elastic properties, are also computed. The anisotropy analyses indicate obvious elastic anisotropy for α-SnS along different symmetry planes and axes. Moreover, calculations demonstrate that α-SnS is an indirect gap semiconductor, and it transforms to semimetal with pressure increasing up to 10.2 GPa. Combined with the density of states, the characters of the band structure have been analysed in detail.
Copeland, Kari L; Anderson, Julie A; Farley, Adam R; Cox, James R; Tschumper, Gregory S
2008-11-13
To examine the effects of pi-stacking interactions between aromatic amino acid side chains and adenine bearing ligands in crystalline protein structures, 26 toluene/(N9-methyl)adenine model configurations have been constructed from protein/ligand crystal structures. Full geometry optimizations with the MP2 method cause the 26 crystal structures to collapse to six unique structures. The complete basis set (CBS) limit of the CCSD(T) interaction energies has been determined for all 32 structures by combining explicitly correlated MP2-R12 computations with a correction for higher-order correlation effects from CCSD(T) calculations. The CCSD(T) CBS limit interaction energies of the 26 crystal structures range from -3.19 to -6.77 kcal mol (-1) and average -5.01 kcal mol (-1). The CCSD(T) CBS limit interaction energies of the optimized complexes increase by roughly 1.5 kcal mol (-1) on average to -6.54 kcal mol (-1) (ranging from -5.93 to -7.05 kcal mol (-1)). Corrections for higher-order correlation effects are extremely important for both sets of structures and are responsible for the modest increase in the interaction energy after optimization. The MP2 method overbinds the crystal structures by 2.31 kcal mol (-1) on average compared to 4.50 kcal mol (-1) for the optimized structures.
Holland, Diane; Jenkins, H Donald Brooke
2012-05-07
Standard thermochemical data (in the form of Δ(f)H° and Δ(f)G°) are available for crystalline (c) materials but rarely for their corresponding amorphous (a) counterparts. This paper establishes correlations between the sets of data for the two material forms (where known), which can then be used as a guideline for estimation of missing data. Accordingly, Δ(f)H°(a)/kJ mol(-1) ≈ 0.993Δ(f)H°(c)/kJ mol(-1) + 12.52 (R(2) = 0.9999; n = 50) and Δ(f)G°/kJ mol(-1) ≈ 0.988Δ(f)H°(c)/kJ mol(-1) + 0.70 (R(2) = 0.9999; n = 10). Much more tentatively, we propose that S°(298)(c)/J K(-1) mol(-1) ≈ 1.084S°(298)(c)/J K(-1) mol(-1) + 6.54 (R(2) = 0.9873; n = 11). An amorphous hydrate enthalpic version of the Difference Rule is also proposed (and tested) in the form [Δ(f)H°(M(p)X(q)·nH(2)O,a) - Δ(f)H°(M(p)X(q),a)]/kJ mol(-1) ≈ Θ(Hf)n ≈ -302.0n, where M(p)X(q)·nH(2)O represents an amorphous hydrate and M(p)X(q) the corresponding amorphous anhydrous parent salt.
Reyes, Archie C; Koudelka, Astrid P; Amyes, Tina L; Richard, John P
2015-04-29
The side chain cation of R269 lies at the surface of l-glycerol 3-phosphate dehydrogenase (GPDH) and forms an ion pair to the phosphodianion of substrate dihydroxyacetone phosphate (DHAP), which is buried at the nonpolar protein interior. The R269A mutation of GPDH results in a 110-fold increase in K(m) (2.8 kcal/mol effect) and a 41,000-fold decrease in k(cat) (6.3 kcal/mol effect), which corresponds to a 9.1 kcal/mol destabilization of the transition state for GPDH-catalyzed reduction of DHAP by NADH. There is a 6.7 kcal/mol stabilization of the transition state for the R269A mutant GPDH-catalyzed reaction by 1.0 M guanidinium ion, and the transition state for the reaction of the substrate pieces is stabilized by an additional 2.4 kcal/mol by their covalent attachment at wildtype GPDH. These results provide strong support for the proposal that GPDH invests the 11 kcal/mol intrinsic phosphodianion binding energy of DHAP in trapping the substrate at a nonpolar active site, where strong electrostatic interactions are favored, and obtains a 9 kcal/mol return from stabilizing interactions between the side chain cation and transition state trianion. We propose a wide propagation for the catalytic motif examined in this work, which enables strong transition state stabilization from enzyme-phosphodianion pairs.
NASA Technical Reports Server (NTRS)
Signorini, Sergio R.; McClain, Charles R.; Christian, James R.
2001-01-01
An ecosystem-carbon cycle model is used to analyze the biogeochemical-physical interactions and carbon fluxes in the Bermuda Atlantic Time-series Study (BATS) site for the period of 1992-1998. The model results compare well with observations (most variables are within 8% of observed values). The sea-air flux ranges from -0.32 to -0.50 mol C/sq m/yr, depending upon the gas transfer algorithm used. This estimate is within the range (-0.22 to -0.83 mol C/sq m/yr) of previously reported values which indicates that the BATS region is a weak sink of atmospheric CO2. The overall carbon balance consists of atmospheric CO2 uptake of 0.3 Mol C/sq m/yr, upward dissolved inorganic carbon (DIC) bottom flux of 1.1 Mol C/sq m/yr, and carbon export of 1.4 mol C/sq m/yr via sedimentation. Upper ocean DIC levels increased between 1992 and 1996 at a rate of approximately 1.2 (micro)mol/kg/yr, consistent with observations. However, this trend was reversed during 1997-1998 to -2.7 (micro)mol/kg/yr in response to hydrographic changes imposed by the El Nino-La Nina transition, which were manifested in the Sargasso Sea by the warmest SST and lowest surface salinity of the period (1992-1998).
Shamsudin, Norzianah; Tan, Ai Ling; Wimmer, Franz L; Young, David J; Tiekink, Edward R T
2015-09-01
The asymmetric unit of the title compound, 2[Zn(C32H16N8)(C7H9N)]·3C7H9N, comprises two independent complex mol-ecules and three benzyl-amine solvent mol-ecules. Each complex mol-ecule features a penta-coordinated Zn(2+) ion within a square-pyramidal geometry, whereby the N5 donor set is defined by four atoms of the phthalocyaninate dianion (PC) and an N-bound benzyl-amine mol-ecule; it is the relative orientations of the latter that differentiate between the independent complex mol-ecules. The uncoordinated benzyl-amine mol-ecules display different conformations in the structure, with syn-Car-Car-Cm-N (ar = aromatic, m = methyl-ene) torsion angles spanning the range -28.7 (10) to 35.1 (14)°. In the crystal, N-H⋯N and N-H⋯π inter-actions lead to supra-molecular layers in the ab plane. The layers have a zigzag topology, have the coordinating and non-coordinating benzyl-amine mol-ecules directed to the inside, and present the essentially flat PC resides to the outside. This arrangement enables adjacent layers to associate via π-π inter-actions [inter-centroid distance between pyrrolyl and fused-benzene rings = 3.593 (2) Å] so that a three-dimensional architecture is formed.
Chen, Nan; Zhang, Jie; Xu, Min; Wang, Ting; Wang, Yu-ling; Pei, Ying-hua
2013-09-01
To observe the inhibitory effect and potential mechanism of mitomycin C and paclitaxel on the proliferation of Human Pulmonary Fibroblast in vitro. So as to providing an experimental reference for the design of drug eluting airway stents. Cell viability was measured by MTT assay after different concentrations of mitomycin C or paclitaxel varying from 10(-1)1 mol/L to 10(-4) mol/L had been applied to the fibroblasts for 24, 48 or 72 h, respectively. Cell apoptosis was assessed by flow cytometry using dual staining with annexin V-FITC and propidium iodide 48 h after administering mitomycin C or paclitaxel at a concentration of 5×10(-6), 10(-5), 5×10(-5), 10(-4), 2×10(-4) mol/L, respectively. And the morphological character of cell apoptosis was observed by Hoechst 33342 fluorescent staining. The results of MTT revealed that cell proliferation were inhibited by mitomycin C and paclitaxel at all concentrations and exposure times. Among them, the inhibitory effect of mitomycin C were weak when the concentrations were between 10(-1)1 mol/L to 10(-8) mol/L. And within this context, the inhibitory ratio didn't correspond to the elevation of the concentration or the prolongation of the exposure times.However, when the concentration were between 10(-7) mol/L to 10(-4) mol/L, the inhibitory ratio rise progressively as the elevation of the concentration at all exposure times. The inhibitory ratio were 53.52%, 60.23%, 89.81% and 96.47% respectively when cells were treated by 10(-7), 10(-6), 10(-5) mol/L and 10(-4) mol/L mitomycin C for 72 h. An apparent "threshold dose effect" was observed in the paclitaxel treated groups.It's worth noting that the inhibitory ratio was only 48.22% when the cells had already been treated by 10(-5) mol/L paclitaxel for 72 h.However, when the concentration had reached 10(-4) mol/L, the inhibitory ratio sharply climbed to 93.38% even the cells had only been treated for 24 h. And the inhibitory ratio continued to rise as time prolonged. The results of cell apoptosis were consistent with MTT.When a significant inhibitory effect were detected by MTT, remarkable cell apoptosis could be observed by flow cytometry, and typical apoptotic cell could be identified by Hoechst 33342 fluorescent staining. A certain concentration of mitomycin C or paclitaxel can inhibit Human Pulmonary Fibroblast proliferation in vitro. Both of these two drugs have potential value for the preparation of drug eluting airway stents. In order to ensure the inhibitory effect, the eluting concentration of mitomycin C and paclitaxel should not be less than 10(-7) mol/L and 10(-5) mol/L. But the eluting concentration of these two drugs should not exceed 10(-4) mol/L when both of the inhibitory ratio of these two drugs were higher than 95%.On this basis, elevating the drug concentration has little significance for improving the inhibitory effect, but increase the risk of systemic toxicity. Inducing cell apoptosis is one of the potential mechanisms of mitomycin C and paclitaxel in inhibiting cell proliferation.
A 300,000-mol-wt intermediate filament-associated protein in baby hamster kidney (BHK-21) cells.
Yang, H Y; Lieska, N; Goldman, A E; Goldman, R D
1985-02-01
Native intermediate filament (IF) preparations from the baby hamster kidney fibroblastic cell line (BHK-21) contain a number of minor polypeptides in addition to the IF structural subunit proteins desmin, a 54,000-mol-wt protein, and vimentin, a 55,000-mol-wt protein. A monoclonal antibody was produced that reached exclusively with a high molecular weight (300,000) protein representative of these minor proteins. Immunological methods and comparative peptide mapping techniques demonstrated that the 300,000-mol-wt species was biochemically distinct from the 54,000- and 55,000-mol-wt proteins. Double-label immunofluorescence observations on spread BHK cells using this monoclonal antibody and a rabbit polyclonal antibody directed against the 54,000- and 55,000-mol-wt proteins showed that the 300,000-mol-wt species co-distributed with IF in a fibrous pattern. In cells treated with colchicine or those in the early stages of spreading, double-labeling with these antibodies revealed the co-existence of the respective antigens in the juxtanuclear cap of IF that is characteristic of cells in these physiological states. After colchicine removal, or in the late stages of cell spreading, the 300,00-mol-wt species and the IF subunits redistributed to their normal, highly coincident cytoplasmic patterns. Ultrastructural localization by the immunogold technique using the monoclonal antibody supported the light microscopic findings in that the 300,000-mol-wt species was associated with IF in the several physiological and morphological cell states investigated. The gold particle pattern was less intimately associated with IF than that defined by anti-54/55 and was one of non-uniform distribution along IF, being clustered primarily at points of proximity between IF, where an amorphous, proteinaceous material was often the labeled element. Occasionally, "bridges" of label were seen extending outward from such clusters on IF. Gold particles were infrequently bound to microtubules, microfilaments, or other cellular organelles, and when so, IF were usually contiguous. During multiple cycles of in vitro disassembly/assembly of the IF from native preparations, the 300,000-mol-wt protein remained in the fraction containing the 54,000- and 55,000-mol-wt structural subunits, whether the latter were in the soluble state or pelleted as formed filaments. In keeping with the nomenclature developed for the microtubule-associated proteins (MAPs), the acronym IFAP-300K (intermediate filament associated protein) is proposed for this molecule.
Tonin, Marlon D L; Garden, Simon J; Jotani, Mukesh M; Wardell, Solange M S V; Wardell, James L; Tiekink, Edward R T
2017-05-01
The asymmetric unit of the title co-crystal, C 10 H 5 BrO 2 ·C 14 H 8 O 4 [systematic name: 2-bromo-1,4-di-hydro-naphthalene-1,4-dione-1,8-dihy-droxy-9,10-di-hydro-anthracene-9,10-dione (1/1)], features one mol-ecule of each coformer. The 2-bromo-naphtho-quinone mol-ecule is almost planar [r.m.s deviation of the 13 non-H atoms = 0.060 Å, with the maximum deviations of 0.093 (1) and 0.099 (1) Å being for the Br atom and a carbonyl-O atom, respectively]. The 1,8-di-hydroxy-anthra-quinone mol-ecule is planar (r.m.s. deviation for the 18 non-H atoms is 0.022 Å) and features two intra-molecular hy-droxy-O-H⋯O(carbon-yl) hydrogen bonds. Dimeric aggregates of 1,8-di-hydroxy-anthra-quinone mol-ecules assemble through weak inter-molecular hy-droxy-O-H⋯O(carbon-yl) hydrogen bonds. The mol-ecular packing comprises stacks of mol-ecules of 2-bromo-naphtho-quinone and dimeric assembles of 1,8-di-hydroxy-anthra-quinone with the shortest π-π contact within a stack of 3.5760 (9) Å occurring between the different rings of 2-bromo-naphtho-quinone mol-ecules. The analysis of the Hirshfeld surface reveals the importance of the inter-actions just indicated but, also the contribution of additional C-H⋯O contacts as well as C=O⋯π inter-actions to the mol-ecular packing.
Leaf water use efficiency of C{sub 4} plants grown at glacial to elevated CO{sub 2} concentrations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Polley, H.W.; Johnson, H.B.; Mayeux, H.S.
1995-09-01
Leaf gas exchange and stable carbon isotope compositions were measured on C{sub 4} species grown from near glacial to current CO{sub 2} concentrations (200 to 350 {mu}mol/mol) and from the current concentration to levels possible in the future (700 and 1000 {mu}mol/mol) to determine effects of rising CO{sub 2} on intrinsic water use efficiency (CO{sub 2} assimilation, A/stomatal conductance to water, g) of C{sub 4} plants. The increase in A/g was proportionally greater than that in CO{sub 2} from near glacial to present concentrations in the perennial grass Schizachyrium scoparium and, in one of two years, in the annual grassmore » Zea mays, because of a corresponding decrease in the ratio of leaf intercellular (c{sub i}) to external CO{sub 2} concentration (c{sub a}). Leaf A/g increased 66% in S. scoparium and 80% in the perennial shrub Atriplex canescens from 350 to 700 {mu}mol/mol CO{sub 2}, but averaged across species declined 15% from 700 to 1000 {mu}mol/mol because of an accompanying increase in c{sub i}/c{sub a}. At each CO{sub 2} level, A/g was higher in the grass than shrub. There were substantial differences in A/g at a given CO{sub 2} concentration and in the response of A/g to CO{sub 2} among the species examined. Because much of the positive response of C{sub 4} plants to CO{sub 2} derives from higher water use efficiency, these differences could influence the relative productivities of C{sub 4} species.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petroianu, G.A.; Hasan, M.Y.; Nurulain, S.M.
Recently, the FDA approved the medical use of oral pyridostigmine as prophylactic treatment of possible nerve agent exposure: the concept is to block the cholinesterase transitorily using the carbamate (pyridostigmine) in order to deny access to the active site of the enzyme to the irreversible inhibitor (nerve agent) on subsequent exposure. We have shown previously that tiapride is in vitro a weak inhibitor of acetylcholinesterase and that in rats administration of tiapride before the organophosphate paraoxon significantly decreases mortality. The purpose of the present study was to compare tiapride- and pyridostigmine-based pretreatment strategies, either alone or in combination with pralidoximemore » reactivation, by using a prospective, non-blinded study in a rat model of acute high-dose paraoxon exposure. Groups 1-6 received 1 {mu}Mol paraoxon ({approx} LD{sub 75}) groups 2-6 received in addition: G{sub 2} 50 {mu}Mol tiapride 30 min before paraoxon; G{sub 3} 50 {mu}Mol tiapride 30 min before paraoxon and 50 {mu}Mol pralidoxime 1 min after paraoxon; G{sub 4} 1 {mu}Mol pyridostigmine 30 min before paraoxon; G{sub 5} 1 {mu}Mol pyridostigmine 30 min before paraoxon and 50 {mu}Mol pralidoxime 1 min after paraoxon; G{sub 6} 50 {mu}Mol pralidoxime 1 min after paraoxon; Mortality data were compared using Kaplan-Meier plots and logrank tests. Mortality is statistically significantly influenced by all treatment strategies. Tiapride pretreatment followed by pralidoxime treatment (G{sub 3}) is aux par with pyridostigmine pretreatment followed by pralidoxime treatment (G{sub 5}). Tiapride pretreatment only (G{sub 2}) is inferior to pyridostigmine pretreatment only (G{sub 4}). The best results are achieved with pyridostigmine pretreatment only or pralidoxime treatment only (G{sub 4} and G{sub 6})« less
Al-Omary, Fatmah A M; El-Emam, Ali A; Ghabbour, Hazem A; Chidan Kumar, C S; Quah, Ching Kheng; Fun, Hoong-Kun
2015-03-01
The title 1,3,4-oxa-diazole-2-thione derivative, C18H20N4OS2, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. The 2-thienyl rings in both mol-ecules are rotationally disordered over two orientations by approximately 180° about the single C-C bond that connects it to the oxa-diazole thione ring; the ratios of site occupancies for the major and minor components were fixed in the structure refinement at 0.8:0.2 and 0.9:0.1 in mol-ecules A and B, respectively. The 1,3,4-oxa-diazole-2-thione ring forms dihedral angles of 7.71 (16), 10.0 (11) and 77.50 (12)° (mol-ecule A), and 6.5 (3), 6.0 (9) and 55.30 (12)° (mol-ecule B) with the major and minor parts of the disordered thio-phene ring and the mean plane of the adjacent piperazine ring, respectively, resulting in approximately V-shaped conformations for the mol-ecules. The piperazine ring in both mol-ecules adopts a chair conformation. The terminal benzene ring is inclined towards the mean plane of the piperazine ring with N-C-C-C torsion angles of -58.2 (3) and -66.2 (3)° in mol-ecules A and B, respectively. In the crystal, no inter-molecular hydrogen bonds are observed. The crystal packing features short S⋯S contacts [3.4792 (9) Å] and π-π inter-actions [3.661 (3), 3.664 (11) and 3.5727 (10) Å], producing a three-dimensional network.
Amine binding and oxidation at the catalytic site for photosynthetic water oxidation
Ouellette, Anthony J. A.; Anderson, Lorraine B.; Barry, Bridgette A.
1998-01-01
Photosynthetic water oxidation occurs at the Mn-containing catalytic site of photosystem II (PSII). By the use of 14C-labeled amines and SDS-denaturing PAGE, covalent adducts derived from primary amines and the PSII subunits, CP47, D2/D1, and the Mn-stabilizing protein, can be observed. When PSII contains the 18- and 24-kDa extrinsic proteins, which restrict access to the active site, no 14C labeling is obtained. NaCl, but not Na2SO4, competes with 14C labeling in Mn-containing PSII preparations, and the concentration dependence of this competition parallels the activation of oxygen evolution. Formation of 14C-labeled adducts is observed in the presence or in the absence of a functional manganese cluster. However, no significant Cl− effect on 14C labeling is observed in the absence of the Mn cluster. Isolation and quantitation of the 14C-labeled aldehyde product, produced from [14C]benzylamine, gives yields of 1.8 ± 0.3 mol/mol PSII and 2.9 ± 0.2 mol/mol in Mn-containing and Mn-depleted PSII, respectively. The corresponding specific activities are 0.40 ± 0.07 μmol(μmol PSII-hr)−1 and 0.64 ± 0.04 μmol(μmol PSII-hr)−1. Cl− suppresses the production of [14C]benzaldehyde in Mn-containing PSII, but does not suppress the production in Mn-depleted preparations. Control experiments show that these oxidation reactions do not involve the redox-active tyrosines, D and Z. Our results suggest the presence of one or more activated carbonyl groups in protein subunits that form the active site of PSII. PMID:9482863
Apparent bioavailability of isoflavones after intake of liquid and solid soya foods
Franke, Adrian A.; Ashburn, Leslie A.; Kakazu, Kerry; Suzuki, Shana; Wilkens, Lynne R.; Halm, Brunhild M.
2015-01-01
Isoflavone (IFL) intake may provide numerous health benefits, but IFL bioavailability differences among soya foods remains uncertain. Urinary IFL excretion (UIE) was shown to provide a reliable surrogate for systemic IFL exposure and therefore can be used as a measure of ‘apparent bioavailability’ (AB). We investigated the AB of IFL in fourteen healthy adults, consuming two liquid and two solid soya foods in a crossover designed study. Volunteers consumed the foods with a self-selected breakfast, which was kept identical for all four soya items (soya nuts, soya milk, soya protein bar and soya protein powder drink in water; average 23·7 mg IFL, 88–96 % glycosides, by HPLC analysis) and collected all urine up to 26 h. Liquid foods showed initially higher UIE values than solid foods, but this difference was considerably reduced or disappeared entirely after 24–26 h. Conclusive AB results were obtained only after 24–26 h; earlier collections were not reliable. At 26 h, adjusted UIE values for daidzein (DE) were 20 μmol in the milk and bar and 17 μmol for the nut and powder; urinary genistein excretion was the highest in the milk group (10 μmol) followed by the nut, bar (both 6 μmol) and powder groups (5 μmol); the UIE for glycitein was the highest for bars (4 μmol), followed by powder and nuts (3 μmol), and milk (2 μmol). DE makes the largest contribution to urinary total IFL. The AB of IFL was found to be variable depending on the analyte and soya food consumed. PMID:19450369
Hermann-Krauss, Carmen; Koller, Martin; Stelzer, Franz; Braunegg, Gerhart
2013-01-01
The archaeon Haloferax mediterranei was selected for production of PHA co- and terpolyesters using inexpensive crude glycerol phase (CGP) from biodiesel production as carbon source. CGP was assessed by comparison with the application of pure glycerol. Applying pure glycerol, a copolyester with a molar fraction of 3-hydroxybutyrate (3HB) of 0.90 mol/mol and 3-hydroxyvalerate (3HV) of 0.10 mol/mol, was produced at a volumetric productivity of 0.12 g/Lh and an intracellular PHA content of 75.4 wt.-% in the sum of biomass protein plus PHA. Application of CGP resulted in the same polyester composition and volumetric productivity, indicating the feasibility of applying CGP as feedstock. Analysis of molar mass distribution revealed a weight average molar mass M w of 150 kDa and polydispersity P i of 2.1 for pure glycerol and 253 kDa and 2.7 for CGP, respectively; melting temperatures ranged between 130 and 140°C in both setups. Supplying γ-butyrolactone as 4-hydroxybutyrate (4HB) precursor resulted in a poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyvalerate-co-4-hydroxybutyrate] (PHBHV4HB) terpolyester containing 3HV (0.12 mol/mol) and 4HB (0.05 mol/mol) in the poly[(R)-3-hydroxybutyrate] (PHB) matrix; in addition, this process runs without sterilization of the bioreactor. The terpolyester displayed reduced melting (melting endotherms at 122 and 137°C) and glass transition temperature (2.5°C), increased molar mass (391 kDa), and a polydispersity similar to the copolyesters. PMID:24453697
Lano, Ian Marie; Lyon, Andrew W; Wang, Li; Ruskin, Rob; Lyon, Martha E
2018-03-01
Clinically significant variation has been reported within and between plasma and whole blood total bilirubin methods used to identify neonates for whom clinical intervention for hyperbilirubinemia may be required. To evaluate total bilirubin measurements between the Radiometer whole blood co-oximeter and plasma bilirubin methods from Roche Diagnostics and Ortho Clinical Diagnostics using neonatal specimens. Total bilirubin levels were analyzed by whole blood co-oximetry (Radiometer® ABL90). Specimens were centrifuged and plasma analyzed for total bilirubin with a diazo method (Roche Cobas® C-601) and a reflectance spectrophotometric BuBc dry film method (Ortho Clinical Diagnostics VITROS® 350). Results were evaluated by regression, Bland-Altman comparisons and t-tests. The patient correlation study yielded the following regression equations in μmol/L: a) Radiometer=1.03 Roche - 3.5μmol/L b) Radiometer=0.98 Ortho - 5.7μmol/L c) Roche=0.97 Ortho - 2.4μmol/L. The mean bias over the range of total bilirubin levels examined was -1.0μmol/L for the Radiometer versus the Roche (p≤0.305); -4.4μmol/L for the Radiometer versus Ortho (p≤0.005) and -4.4μmol/L for the Roche versus Ortho (p≤0.002). Whole blood total bilirubin measurement using the Radiometer ABL90 blood gas analyzer provides accurate and precise results compared to the Roche plasma diazo method. Compared to the reflectance spectrophotometric method, results are precise and had a small but statistically significant bias of -4.4μmol/L. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Jiang, Liqun; Ji, Yan; Hu, Wenrong; Pei, Haiyan; Nie, Changliang; Ma, Guixia; Song, Mingming
2016-09-01
Light is one of the most important factors affecting microalgae growth and biochemical composition. The influence of illumination on Chlorella vulgaris cultivated with diluted monosodium glutamate wastewater (MSGW) was investigated. Six progressive illumination intensities (0, 30, 90, 150, 200 and 300μmol·m(-2)s(-1)), were used for C. vulgaris cultivation at 25°C. Under 150μmol·m(-2)s(-1), the corresponding specific light intensity of 750×10(-6)μmol·m(-2)s(-1) per cell, algae obtained the maximum biomass concentration (1.46g·L(-1)) on the 7th day, which was 3.5 times of that under 0μmol·m(-2)s(-1), and the greatest average specific growth rate (0.79 d(-1)) in the first 7days. The results showed the importance role of light in mixotrophic growth of C. vulgaris. High light intensities of 200 and 300μmol·m(-2)s(-1) would inhibit microalgae growth to a certain degree. The algal lipid content was the greatest (30.5%) at 150μmol·m(-2)s(-1) light intensity, which was 2.42 times as high as that cultured in dark. The protein content of C. vulgaris decreased at high light intensities of 200 and 300μmol·m(-2)s(-1). The effect of irradiance on carbohydrate content was inversely correlated with that on protein. The available light at an appropriate intensity, not higher than 200μmol·m(-2)s(-1), was feasible for economical cultivation of C. vulgaris in MSGW. Copyright © 2016 Elsevier B.V. All rights reserved.
Kaur, Gurkamaljit; Pandey, Bharati; Grover, Arbind; Garewal, Naina; Grover, Abhinav; Kaur, Jagdeep
2018-03-30
The lipolytic protein LipU was conserved in mycobacterium sp. including M. tuberculosis (MTB LipU) and M. leprae (MLP LipU). The MTB LipU was identified in extracellular fraction and was reported to be essential for the survival of mycobacterium. Therefore to address the problem of drug resistance in pathogen, LipU was selected as a drug target and the viability of finding out some FDA approved drugs as LipU inhibitors in both the cases was explored. Three-dimensional (3D) model structures of MTB LipU and MLP LipU were generated and stabilized through molecular dynamics (MD). FDA approved drugs were screened against these proteins. The result showed that the top-scoring compounds for MTB LipU were Diosmin, Acarbose and Ouabain with the Glide XP score of -12.8, -11.9 and -11.7 kcal/mol, respectively, whereas for MLP LipU protein, Digoxin (-9.2 kcal/mol), Indinavir (-8.2 kcal/mol) and Travoprost (-8.2 kcal/mol) showed highest affinity. These drugs remained bound in the active site pocket of MTB LipU and MLP LipU structure and interaction grew stronger after dynamics. RMSD, RMSF and Rg were found to be persistent throughout the simulation period. Hydrogen bonds along with large number of hydrophobic interactions stabilized the complex structures. Binding free energies obtained through Prime/MM-GBSA were found in the significant range from -63.85 kcal/mol to -34.57 kcal/mol for MTB LipU and -71.33 kcal/mol to -23.91 kcal/mol for MLP LipU. The report suggested high probability of these drugs to demolish the LipU activity and could be probable drug candidates to combat TB and leprosy disease.
The temperature-dependence of adenylate cyclase from baker's yeast.
Londesborough, J; Varimo, K
1979-01-01
The Michaelis constant of membrane-bound adenylate cyclase increased from 1.1 to 1.8 mM between 7 and 38 degrees C (delta H = 13 kJ/mol). Over this temperature range, the maximum velocity increased 10-fold, and the Arrhenius plot was nearly linear, with an average delta H* of 51 kJ/mol. The temperature-dependence of the reaction rate at 2 mM-ATP was examined in more detail: for Lubrol-dispersed enzyme, Arrhenius plots were nearly linear with average delta H* values of 45 and 68 kJ/mol, respectively, for untreated and gel-filtered enzymes; for membrane-bound enzyme, delta H changed from 40 kJ/mol above about 21 degrees C to 62 kJ/mol below 21 degrees C, but this behaviour does not necessarily indicate an abrupt, lipid-induced, transition in the reaction mechanism. PMID:391221
Crystal structure of 3-hy-droxy-methyl-1,2,3,4-tetra-hydro-isoquinolin-1-one.
Caracelli, Ignez; Hino, Camila Lury; Zukerman-Schpector, Julio; Biaggio, Francisco Carlos; Tiekink, Edward R T
2015-08-01
In the title compound, C10H11NO2, two independent but virtually superimposable mol-ecules, A and B, comprise the asymmetric unit. The heterocyclic ring in each mol-ecule has a screw-boat conformation, and the methyl-hydroxyl group occupies a position to one side of this ring with N-C-C-O torsion angles of -55.30 (15) (mol-ecule A) and -55.94 (16)° (mol-ecule B). In the crystal, O-H⋯O and N-H⋯O hydrogen bonding leads to 11-membered {⋯HNCO⋯HO⋯HNC2O} heterosynthons, involving three different mol-ecules, which are edge-shared to generate a supra-molecular chain along the a axis. Inter-actions of the type C-H⋯O provide additional stability to the chains, and link these into a three-dimensional architecture.
Crankshaw, D L; Hetnarski, K; Wilkinson, C F
1979-09-01
1. NADPH-cytochrome c reductase was solubilized with bromelain and purified about 400-fold from sucrose/pyrophosphate-washed microsomal fractions from southern armyworm (Spodoptera eridania) larval midguts. 2. The enzyme has a mol.wt. of 70 035 +/- 1300 and contained 2 mol of flavin/mol of enzyme consisting of almost equimolar amounts of FMN and FAD. 3. Aerobic titration of the enzyme with NADPH caused the formation of a stable half-reduced state at 0.5 mol of NADPH/mol of flavin. 4. Kinetic analysis showed that the reduction of cytochrome c proceeded by a Bi Bi Ping Pong mechanism. 5. Apparent Km values for NADPH and cytochrome c and Ki values for NADP+ and 2'-AMP were considerably higher for the insect reductase than for the mammalian liver enzyme. 6. These are discussed in relation to possible differences in the active sites of the enzymes.
N-(1-Allyl-1H-indazol-5-yl)-4-methyl-benzene-sulfonamide.
Chicha, Hakima; Rakib, El Mostapha; Abderrafia, Hafid; Saadi, Mohamed; El Ammari, Lahcen
2013-11-30
The asymmetric unit of the title compound, C17H17N3O2S, contains two independent mol-ecules linked by an N-H⋯O hydrogen bond. The mol-ecules show different conformations. In the first mol-ecule, the fused five- and six-membered ring system is almost perpendicular to the plane through the atoms forming the allyl group, as indicated by the dihedral angle of 85.1 (4)°. The dihedral angle with the methyl-benzene-sulfonamide group is 78.8 (1)°. On the other hand, in the second mol-ecule, the dihedral angles between the indazole plane and the allyl and methyl-benzene-sulfonamide groups are 80.3 (3) and 41.5 (1)°, respectively. In the crystal, mol-ecules are further linked by N-H⋯N and C-H⋯O hydrogen bonds, forming a three-dimensional network.
Li, Jing; Cui, Bencang; Wang, Huining; Lin, Yuanhua; Deng, Xuliang; Li, Ming; Nan, Cewen
2016-01-01
Composite ceramics BaTiO3/3Y-TZP containing 0 mol %, 3 mol %, 5 mol %, 7 mol %, and 10 mol % BaTiO3 have been prepared by conventional sintering and spark-plasma sintering (SPS), respectively. Analysis of the XRD patterns and Raman spectra reveal that the phase composition of t-ZrO2, m-ZrO2, and BaTiO3 has been obtained. Our results indicate that SPS can be effective for the decrease in grain size and porosity compared with conventional sintering, which results in a lower concentration of m-ZrO2 and residual stress. Therefore, the fracture toughness is enhanced by the BaTiO3 phase through the SPS technique, while the behavior was impaired by the piezoelectric second phase through conventional sintering. PMID:28773445
40 CFR 1065.750 - Analytical gases.
Code of Federal Regulations, 2014 CFR
2014-07-01
... recommend using a balance gas of purified nitrogen. (v) FID CH 4 span gas. If you always span and calibrate....41) mol/mol, balance He or N2, and a stated total hydrocarbon concentration of 0.05 µmol/mol or less. For GC-FIDs that measure methane (CH4) using a FID fuel that is balance N2, perform the CH4...
N-(3-Chloro-1-methyl-1H-indazol-5-yl)-4-methylbenzene-sulfonamide.
Chicha, Hakima; Rakib, El Mostapha; Amiri, Ouafa; Saadi, Mohamed; El Ammari, Lahcen
2014-02-01
The asymmetric unit of the title compound, C15H14ClN3O2S, contains two independent mol-ecules showing different conformations: in one mol-ecule, the indazole ring system makes a dihedral angle of 51.5 (1)° with the benzene ring whereas in the other, the indazole unit is almost perpendicular to the benzene ring [dihedral angle 77.7 (1)°]. In the crystal, the mol-ecules are linked by N-H⋯N and N-H⋯O hydrogen bonds, forming a set of four mol-ecules linked in pairs about an inversion centre.
3-Aminobenzoic acid–1,2-bis(4-pyridyl)ethane (1/1)
Shen, Fwu Ming; Lush, Shie Fu
2010-01-01
The asymmetric unit of the title compound, C12H12N2·C7H7NO2, contains two 3-aminobenzoic acid molecules and two 1,2-bis(4-pyridyl)ethane molecules. In the two 1,2-bis(4-pyridyl)ethane molecules, the dihedral angles between the pyridyl rings are 2.99 (9) and 46.78 (8)°. In the crystal, the molecules associate through amine and carboxyl group N—H⋯O=C interactions between one of the 3-aminobenzoic acid molecules and one of the 1,2-bis(4-pyridyl)ethane molecules, generating R 2 2(14) dimers, which are extended head-to-tail via amine and pyridine N—H⋯N hydrogen bonds. Intermolecular O—H⋯N, N—H⋯O, N—H⋯N and C—H⋯O hydrogen bonding are observed in the crystal structure. C—H⋯π and π–π stacking interactions [centroid–centroid distance = 3.9985 (10) Å] are also present. PMID:21579186
NASA Astrophysics Data System (ADS)
Sulistyo Dwi K., P.; Arindra Trisna, W.; Vindri Catur P., W.; Wijayanti, Erna; Ichsan, Mochammad
2016-03-01
One of the efforts to prevent Alzheimer's disease becomes more severe is by inhibiting the activity of Human acetylcholinesterase enzyme (PDB ID: 4BDT). In this study, virtual screening againts 885 natural compounds from AfroDB has been done using MTIOpenScreen and this step has been successful in identifying ZINC15121024 (-12,9) and ZINC95486216 (-12,7) as the top rank compounds. This data then strengthened by the results of second docking step using Autodock software that has been integrated in PyRx 0.8 software. From this stage, ZINC95486216 (-11,3 kcal/mol) is a compound with the most negative binding affinity compared with four Alzheimer's drugs that have been officially used to date including Rivastigmine (-6,3 Kcal/mol), Donepenzil (-7.9 kcal/mol), Galantamine (-8.4 kcal/mol), and Huprine W (-7.3 kcal/mol). In addition, based on the results of the 2D and 3D visualization using LigPlus and PyMol softwares, respectively, known that the five compounds above are equally capable of binding to several amino acids (Trp 286, Phe295, and Tyr341) located in the active site of Human Acetylcholinesterase enzyme.
Roy, B C; Sedgewick, G; Aalhus, J L; Basarab, J A; Bruce, H L
2015-12-01
Increased meat toughness with animal age has been attributed to mature trivalent collagen cross-link formation. Intramuscular trivalent collagen cross-link content may be decreased by reducing animal age at slaughter and/or inducing muscle re-modeling with growth promotants. This hypothesis was tested in m. gluteus medius (GM) and m. semitendinosus (ST) from 112 beef steers finished at either 12 to 13 (rapid growth) or 18 to 20 (slow growth) months of age. Hereford-Aberdeen Angus (HAA) or Charolais-Red Angus (CRA) steers were randomly assigned to receive implants (IMP), ractopamine (RAC), both IMP and RAC, or none (control). RAC decreased pyridinoline (mol/mol collagen) and IMP increased Ehrlich chromogen (EC) (mol/mol collagen) in the GM. In the ST, RAC increased EC (mol/mol collagen) but decreased EC (nmol/g raw muscle) in slow growing CRA steers. Also, IMP increased ST pyridinoline (nmol/g raw muscle) of slow-growing HAA steers. Results indicated alteration of perimysium collagen cross-links content in muscle in response to growth promotants. Copyright © 2015 Elsevier Ltd. All rights reserved.
Argibay-Otero, Saray; Carballo, Rosa; Vázquez-López, Ezequiel M
2017-10-01
The asymmetric unit of the title compound, [ReCl(C 5 H 5 NO) 2 (CO) 3 ]·C 5 H 5 NO, contains one mol-ecule of the complex fac -[ReCl(4-pyOH) 2 (CO) 3 ] (where 4-pyOH represents 4-hy-droxy-pyridine) and one mol-ecule of pyridin-4(1 H )-one (4-HpyO). In the mol-ecule of the complex, the Re atom is coordinated to two N atoms of the two 4-pyOH ligands, three carbonyl C atoms, in a facial configuration, and the Cl atom. The resulting geometry is slightly distorted octa-hedral. In the crystal structure, both fragments are associated by hydrogen bonds; two 4-HpyO mol-ecules bridge between two mol-ecules of the complex using the O=C group as acceptor for two different HO- groups of coordinated 4-pyOH from two neighbouring metal complexes. The resulting square arrangements are extented into infinite chains by hydrogen bonds involving the N-H groups of the 4-HpyO mol-ecule and the chloride ligands. The chains are further stabilized by π-stacking inter-actions.
Naik, Praveen N; Nandibewoor, Sharanappa T; Chimatadar, Shivamurthi A
2015-06-01
This study was designed to examine the interaction of sulfamethoxazole (SMZ) with human serum albumin(HSA). Spectroscopic analysis of the emission quenching at different temperatures revealed that the quenching mechanism of human serum albumin by SMZ was static mechanism. The binding constant values for the SMZ-HSA system were obtained to be 22,500 L/mol at 288 K, 15,600 L/mol at 298 K, and 8500 L/mol at 308 K. The distance r between donor and acceptor was evaluated according to the theory of Föster energy transfer. The results of spectroscopic analysis and molecular modeling techniques showed that the conformation of human serum albumin had been changed in the presence of SMZ. The thermodynamic parameters, namely enthalpy change (∆ H 0 ) -36.0 kJ/mol, entropy change (∆ S 0 ) -41.3 J/mol K and free energy change (∆ G 0 ) -23.7 kJ/mol, were calculated by using van׳t Hoff equation. The effect of common ions on the binding of SMZ to HSA was tested.
MolTalk – a programming library for protein structures and structure analysis
Diemand, Alexander V; Scheib, Holger
2004-01-01
Background Two of the mostly unsolved but increasingly urgent problems for modern biologists are a) to quickly and easily analyse protein structures and b) to comprehensively mine the wealth of information, which is distributed along with the 3D co-ordinates by the Protein Data Bank (PDB). Tools which address this issue need to be highly flexible and powerful but at the same time must be freely available and easy to learn. Results We present MolTalk, an elaborate programming language, which consists of the programming library libmoltalk implemented in Objective-C and the Smalltalk-based interpreter MolTalk. MolTalk combines the advantages of an easy to learn and programmable procedural scripting with the flexibility and power of a full programming language. An overview of currently available applications of MolTalk is given and with PDBChainSaw one such application is described in more detail. PDBChainSaw is a MolTalk-based parser and information extraction utility of PDB files. Weekly updates of the PDB are synchronised with PDBChainSaw and are available for free download from the MolTalk project page following the link to PDBChainSaw. For each chain in a protein structure, PDBChainSaw extracts the sequence from its co-ordinates and provides additional information from the PDB-file header section, such as scientific organism, compound name, and EC code. Conclusion MolTalk provides a rich set of methods to analyse and even modify experimentally determined or modelled protein structures. These methods vary in complexity and are thus suitable for beginners and advanced programmers alike. We envision MolTalk to be most valuable in the following applications: 1) To analyse protein structures repetitively in large-scale, i.e. to benchmark protein structure prediction methods or to evaluate structural models. The quality of the resulting 3D-models can be assessed by e.g. calculating a Ramachandran-Sasisekharan plot. 2) To quickly retrieve information for (a limited number of) macro-molecular structures, i.e. H-bonds, salt bridges, contacts between amino acids and ligands or at the interface between two chains. 3) To programme more complex structural bioinformatics software and to implement demanding algorithms through its portability to Objective-C, e.g. iMolTalk. 4) To be used as a front end to databases, e.g. PDBChainSaw. PMID:15096277
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miliordos, Evangelos; Xantheas, Sotiris S.
2015-06-21
We report MP2 and CCSD(T) binding energies with basis sets up to pentuple zeta quality for the m = 2-6, 8 clusters. Or best CCSD(T)/CBS estimates are -4.99 kcal/mol (dimer), -15.77 kcal/mol (trimer), -27.39 kcal/mol (tetramer), -35.9 ± 0.3 kcal/mol (pentamer), -46.2 ± 0.3 kcal/mol (prism hexamer), -45.9 ± 0.3 kcal/mol (cage hexamer), -45.4 ± 0.3 kcal/mol (book hexamer), -44.3 ± 0.3 kcal/mol (ring hexamer), -73.0 ± 0.5 kcal/mol (D 2d octamer) and -72.9 ± 0.5 kcal/mol (S4 octamer). We have found that the percentage of both the uncorrected (dimer) and BSSE-corrected (dimer CP e) binding energies recovered with respectmore » to the CBS limit falls into a narrow range for each basis set for all clusters and in addition this range was found to decrease upon increasing the basis set. Relatively accurate estimates (within < 0.5%) of the CBS limits can be obtained when using the “ 2/3, 1/3” (for the AVDZ set) or the “½ , ½” (for the AVTZ, AVQZ and AV5Z sets) mixing ratio between dimer e and dimer CPe. Based on those findings we propose an accurate and efficient computational protocol that can be used to estimate accurate binding energies of clusters at the MP2 (for up to 100 molecules) and CCSD(T) (for up to 30 molecules) levels of theory. This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is a multi program national laboratory operated for DOE by Battelle. This research also used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. AC02-05CH11231.« less
MolTalk--a programming library for protein structures and structure analysis.
Diemand, Alexander V; Scheib, Holger
2004-04-19
Two of the mostly unsolved but increasingly urgent problems for modern biologists are a) to quickly and easily analyse protein structures and b) to comprehensively mine the wealth of information, which is distributed along with the 3D co-ordinates by the Protein Data Bank (PDB). Tools which address this issue need to be highly flexible and powerful but at the same time must be freely available and easy to learn. We present MolTalk, an elaborate programming language, which consists of the programming library libmoltalk implemented in Objective-C and the Smalltalk-based interpreter MolTalk. MolTalk combines the advantages of an easy to learn and programmable procedural scripting with the flexibility and power of a full programming language. An overview of currently available applications of MolTalk is given and with PDBChainSaw one such application is described in more detail. PDBChainSaw is a MolTalk-based parser and information extraction utility of PDB files. Weekly updates of the PDB are synchronised with PDBChainSaw and are available for free download from the MolTalk project page http://www.moltalk.org following the link to PDBChainSaw. For each chain in a protein structure, PDBChainSaw extracts the sequence from its co-ordinates and provides additional information from the PDB-file header section, such as scientific organism, compound name, and EC code. MolTalk provides a rich set of methods to analyse and even modify experimentally determined or modelled protein structures. These methods vary in complexity and are thus suitable for beginners and advanced programmers alike. We envision MolTalk to be most valuable in the following applications:1) To analyse protein structures repetitively in large-scale, i.e. to benchmark protein structure prediction methods or to evaluate structural models. The quality of the resulting 3D-models can be assessed by e.g. calculating a Ramachandran-Sasisekharan plot.2) To quickly retrieve information for (a limited number of) macro-molecular structures, i.e. H-bonds, salt bridges, contacts between amino acids and ligands or at the interface between two chains.3) To programme more complex structural bioinformatics software and to implement demanding algorithms through its portability to Objective-C, e.g. iMolTalk.4) To be used as a front end to databases, e.g. PDBChainSaw.
Sowmya, Haliwana B. V.; Suresha Kumara, Tholappanavara H.; Gopalpur, Nagendrappa; Jasinski, Jerry P.; Millikan, Sean P.; Yathirajan, Hemmige S.; Glidewell, Christopher
2015-01-01
In the molecules of the title compounds, methyl 5-bromo-2-[(2-chloroquinolin-3-yl)methoxy]benzoate, C18H13BrClNO3, (I), methyl 5-bromo-2-[(2-chloro-6-methylquinolin-3-yl)methoxy]benzoate, C19H15BrClNO3, (II), methyl 2-[(2-chloro-6-methylquinolin-3-yl)methoxy]benzoate, C19H16ClNO3, (III), which crystallizes with Z′ = 4 in space group P212121, and 2-chloro-3-[(naphthalen-1-yloxy)methyl]quinoline, C20H14ClNO, (IV), the non-H atoms are nearly coplanar, but in {5-[(2-chloroquinolin-3-yl)methoxy]-4-(hydroxymethyl)-6-methylpyridin-3-yl}methanol, C18H17ClN2O3, (V), the planes of the quinoline unit and of the unfused pyridine ring are almost parallel, although not coplanar. The molecules of (I) are linked by two independent π–π stacking interactions to form chains, but there are no hydrogen bonds present in the structure. In (II), the molecules are weakly linked into chains by a single type of π–π stacking interaction. In (III), three of the four independent molecules are linked by π–π stacking interactions but the other molecule does not participate in such interactions. Weak C—H⋯O hydrogen bonds link the molecules into three types of chains, two of which contain just one type of independent molecule while the third type of chain contains two types of molecule. The molecules of (IV) are linked into chains by a C—H⋯π(arene) hydrogen bond, but π–π stacking interactions are absent. In (V), there is an intramolecular O—H⋯O hydrogen bond, and molecules are linked into sheets by a combination of O—H⋯N hydrogen bonds and π–π stacking interactions. PMID:26090133
[Inhibition of osthole for resorption of rats femur tissue in vitro].
Zhou, Jian; Ren, Xue-mei; Ma, Xiao-ni; Gao, Yu-hai; Yan, Li-juan; Shi, Wen-gui; Chen, Ke-ming
2015-09-01
To investigate osthole effect on femoral tissue resorption activity of rat in vitro. Six SD rats weighted (80 ± 5) g were used to isolate and culture femoral tissue (diaphyses and metaphysis) in vitro. The cultured tissue were devided into control group, estradiol group and osthole group. The femoral tissue was treated with final concentration of 1 x 10(-5) mol/L osthole and 1 x 10(-8) mol/L estradiol culture in vitro at 48 hours after cultured. Tartrate-resistant acid phosphatase (StrACP) activity, glucose and Lactic acid content, StrACP, MCSF (Macrophage colony stimulating factor) and CTSK (Cathepsin K) mRNA was detected by Real-Time RT-PCR were detected. Concetration of Alkaline phosphatase activity were 2226 and 2498 in 1 x 10(-5) mol/L osthole and 1 x 10(-8) mol/L estradiol respectively. As compared with control group, the activity of StrACP of 1 x 10(-5) mol/L osthole and 1 x 10(-8) mol/L estradiol were inhibited at 6, 9, 12 days (P < 0.05); under treatment of in l x 10(-5) mol/L osthole, the content of Lactic acid were increased and the content of glucose were decreased at 3, 6, 9 days (P < 0.05); StrACP, MCSF and CTSK mRNA expression level were inhibited at 6, 9 days (P < 0.05). Osthole can inhibit bone resorption and raise the level of nutrition metabolism of femurs tissue.
Magnusson, Bertil; Ossowicki, Haakan; Rienitz, Olaf; Theodorsson, Elvar
2012-05-01
Healthcare laboratories are increasingly joining into larger laboratory organizations encompassing several physical laboratories. This caters for important new opportunities for re-defining the concept of a 'laboratory' to encompass all laboratories and measurement methods measuring the same measurand for a population of patients. In order to make measurement results, comparable bias should be minimized or eliminated and measurement uncertainty properly evaluated for all methods used for a particular patient population. The measurement as well as diagnostic uncertainty can be evaluated from internal and external quality control results using GUM principles. In this paper the uncertainty evaluations are described in detail using only two main components, within-laboratory reproducibility and uncertainty of the bias component according to a Nordtest guideline. The evaluation is exemplified for the determination of creatinine in serum for a conglomerate of laboratories both expressed in absolute units (μmol/L) and relative (%). An expanded measurement uncertainty of 12 μmol/L associated with concentrations of creatinine below 120 μmol/L and of 10% associated with concentrations above 120 μmol/L was estimated. The diagnostic uncertainty encompasses both measurement uncertainty and biological variation, and can be estimated for a single value and for a difference. This diagnostic uncertainty for the difference for two samples from the same patient was determined to be 14 μmol/L associated with concentrations of creatinine below 100 μmol/L and 14 % associated with concentrations above 100 μmol/L.
Vildagliptin vs sulfonylurea in Indian Muslim diabetes patients fasting during Ramadan
Shete, Abhijit; Shaikh, Aheson; Nayeem, K Javeed; Rodrigues, Lily; Ali, Mohamed Sheikamunadeen Sadiq; Shah, Parag; Khanna, Rajiv; Majid, Sarfaraj; Rasheed, Sabeer A; Shaikh, Shehla; Rahman, Tawfiqur
2013-01-01
AIM: To compare the use of vildagliptin and sulfonylurea with or without metformin in Indian Muslim patients with type 2 diabetes mellitus, fasting during Ramadan. METHODS: This was a 4-wk, multicenter, non-interventional, open-label, observational study. Incidence of hypoglycemic events (HEs), adverse events, and changes in glycosylated hemoglobin A1c (HbA1c), fasting plasma glucose, postprandial plasma glucose and body weight were measured pre- and post-Ramadan. RESULTS: Totally, 97 patients were recruited and all completed the study (vildagliptin group, n = 55; sulfonylurea group, n = 42). HEs were reported in low frequencies in both the vildagliptin and the sulfonylurea groups [0 vs 2 (4.8%) patients, respectively]. Interestingly, HbA1c reduced by -0.43% (-4.71 mmol/mol) in the vildagliptin group [8.75% (72.10 mmol/mol) to 8.32% (67.38 mmol/mol), P = 0.009] while in the sulfonylurea group there was a small increase by 0.01% [0.08 mmol/mol; 8.64% (70.92 mmol/mol) to 8.65% (71.00 mmol/mol), P = 0.958]. Higher percentage of vildagliptin-treated patients achieved HbA1c < 7.0% (< 53 mmol/mol) compared with sulfonylurea (16.4% vs 4.8%). Mean decrease in the body weight was 1.2 kg and 0.03 kg, respectively (P < 0.001). Both treatment groups were well tolerated during Ramadan. CONCLUSION: Vildagliptin is an attractive treatment option for Indian patients with type 2 diabetes mellitus who are fasting during Ramadan. PMID:24379927
Vildagliptin vs sulfonylurea in Indian Muslim diabetes patients fasting during Ramadan.
Shete, Abhijit; Shaikh, Aheson; Nayeem, K Javeed; Rodrigues, Lily; Ali, Mohamed Sheikamunadeen Sadiq; Shah, Parag; Khanna, Rajiv; Majid, Sarfaraj; Rasheed, Sabeer A; Shaikh, Shehla; Rahman, Tawfiqur
2013-12-15
To compare the use of vildagliptin and sulfonylurea with or without metformin in Indian Muslim patients with type 2 diabetes mellitus, fasting during Ramadan. This was a 4-wk, multicenter, non-interventional, open-label, observational study. Incidence of hypoglycemic events (HEs), adverse events, and changes in glycosylated hemoglobin A1c (HbA1c), fasting plasma glucose, postprandial plasma glucose and body weight were measured pre- and post-Ramadan. Totally, 97 patients were recruited and all completed the study (vildagliptin group, n = 55; sulfonylurea group, n = 42). HEs were reported in low frequencies in both the vildagliptin and the sulfonylurea groups [0 vs 2 (4.8%) patients, respectively]. Interestingly, HbA1c reduced by -0.43% (-4.71 mmol/mol) in the vildagliptin group [8.75% (72.10 mmol/mol) to 8.32% (67.38 mmol/mol), P = 0.009] while in the sulfonylurea group there was a small increase by 0.01% [0.08 mmol/mol; 8.64% (70.92 mmol/mol) to 8.65% (71.00 mmol/mol), P = 0.958]. Higher percentage of vildagliptin-treated patients achieved HbA1c < 7.0% (< 53 mmol/mol) compared with sulfonylurea (16.4% vs 4.8%). Mean decrease in the body weight was 1.2 kg and 0.03 kg, respectively (P < 0.001). Both treatment groups were well tolerated during Ramadan. Vildagliptin is an attractive treatment option for Indian patients with type 2 diabetes mellitus who are fasting during Ramadan.
Farahati, J; Coenen, H; Dutschka, K; Stuben, G; Knuhmann, K; Budach, W; Kremens, B; Reiners, C
1997-01-01
The effect of specific activity of meta[I-123]iodobenzylguanidine ([I-123]MIBG) on neuroblastoma uptake was studied in a nude mouse model (NMRI nu/nu) xenografted subcutaneously with SK-N-SH cells. Groups of eight animals received [I-123]MIBG intravenously with a specific activity of greater than or equal to 260 GBq/mu mol (no-carrier-added), 3.7 GBq/mu mol, 37 MBq/mu mol, and 0.37 MBq/mu mol, respectively. All animals in the group injected with 0.37 MBq/mu mol died immediately after the injection. Al 4 and 24 h, there was no significant effect of specific activity on tumor uptake of [I-123]MIBG in the different groups. The uptake of non-tumor tissue was in general lower with 37 MBq/mu mol compared to higher specific activities. The differences in blood, heart, liver, spleen and lungs were statistically significant at 24 h, whereas at 4 h significant differences were only present in the heart, liver and lungs. The results suggest that for the treatment of children with neuroblastoma a lower specific activity of radioiodinated MIBG may minimize the radiation exposure to non-tumor tissue but not to the tumor. Higher mass of MIBG >0.5 mu mol/g, however, is considered as lethal dose in our nude mice model and corresponding doses may cause toxic side effects in human.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lahrich, Sara; University Hassan 1, Laboratoire Sciences des Matériaux, des Milieux et de la Modélisation, 25000 Khouribga; Manoun, Bouchaib
Highlights: • The apatite, K{sub 1−x}Na{sub x}CaPb{sub 3}(PO{sub 4}){sub 3} (0 ≤ x ≤ 1), was synthesized using reaction solid. • The obtained apatite was used to determine mercury in seawater samples from Morocco. • The effect of doping sodium into apatite on physic-chemical parameters was studied. • The influence of the electrochemical variables was investigated to determine mercury. - Abstract: A new chemically modified electrode was synthesized for the determination of mercury(II) using differential pulse anodic stripping voltammetry (DPASV). The electrode was modified by lacunar apatite K{sub 1−x}Na{sub x}CaPb{sub 3}(PO{sub 4}){sub 3} (0 ≤ x ≤ 1) synthesized usingmore » solid reaction. These powders were crystallized in the hexagonal system, space group P6{sub 3}/m. The effect of sodium content on structural, thermodynamic and electrochemical properties of prepared apatite has been studied. Therefore, the best results was obtained using NaCaPb{sub 3}(PO{sub 4}){sub 3} (x = 1) as modifier of carbon paste electrode for the electrochemical detection of mercury(II). The later ions were preconcentrated on the surface of the modified electrode and oxidized at 0.06 V vs. Ag/AgCl. The electroanalytical procedure comprises of two steps: the chemical accumulation of the analyte under open-circuit conditions followed by the electrochemical detection of the preconcentrated species using differential pulse voltammetry. The different parameters that govern the two steps were optimized. A linear response was obtained in the concentration range from 1.0 mol L{sup −1} × 10{sup −4} mol L{sup −1} to 2.0 mol L{sup −1} × 10{sup −7} mol L{sup −1} Hg(II) after activation of the electrode surface under the optimized conditions. The standard deviation was evaluated in a high and low concentration of mercury(II). The values obtained for seven consecutive measurements were 1.24% and 5.07% of 1.0 mol L{sup −1} × 10{sup −4} mol L{sup −1} and 5.0 mol L{sup −1} × 10{sup −6} mol L{sup −1} mercury(II) solutions respectively. The detection limit and quantification limit for mercury(II), calculated from nine times standard deviation of blank/slope of the calibration graph, were 1.086 mol L{sup −1} × 10{sup −8} mol L{sup −1} and 3.62 mol L{sup −1} × 10{sup −8} mol L{sup −1}, respectively. The proposed chemically modified electrode was applied to determine mercury(II) in seawater samples.« less
Improved Kinetic Models for High-Speed Combustion Simulation
2008-06-01
142 Appendix F1: USC_Skeletal_Ethylene_chem.inp ....................................................................... 143 ...to form a strong carbonyl double bond ( keto -Q) gaining 80 kcal mol-1, which is sufficient to immediately cleave the weak RO—OH bond (45 kcal mol-1...in the hydroperoxide. Relative to the stabilized adduct this reaction to ( keto -Q+OH), product set is 65.9 kcal mol-1 below the entrance channel
1-[1-(4-Chloro-phen-yl)ethyl-idene]carbono-hydrazide.
Du, Lingyun; Du, Lei; Wang, Shuhao
2009-08-12
The mol-ecular skeleton of the title mol-ecule, C(9)H(11)ClN(4)O, is essentially planar, the dihedral angle between the ring and the and N/N/C plane being 6.7 (3)°. In the crystal, inter-molecular N-H⋯O and N-H⋯N hydrogen bonds link the mol-ecules into ribbons propagated along [010].
Mader, Felix; Krause, Ludwig; Tokay, Tursonjan; Hakenberg, Oliver W; Köhling, Rüdiger; Kirschstein, Timo
2016-05-01
Purinergic signaling plays a major role in the enteric nervous system, where it governs gut motility through a number of P2X and P2Y receptors. The aim of this study was to investigate the P2Y receptor-mediated motility in rat longitudinal ileum preparations. Ileum smooth muscle strips were prepared from rats, and fixed in an organ bath. Isometric contraction and relaxation responses of the muscle strips were measured with force transducers. Drugs were applied by adding of stock solutions to the organ bath to yield the individual final concentrations. Application of the non-hydrolyzable P2 receptor agonists α,β-Me-ATP or 2-Me-S-ADP (10, 100 μmol/L) dose-dependently elicited a transient relaxation response followed by a sustained contraction. The relaxation response was largely blocked by SK channel blockers apamin (500 nmol/L) and UCL1684 (10 μmol/L), PLC inhibitor U73122 (100 μmol/L), IP3 receptor blocker 2-APB (100 μmol/L) or sarcoendoplasmic Ca(2+) ATPase inhibitor thapsigargin (1 μmol/L), but not affected by atropine, NO synthase blocker L-NAME or tetrodotoxin. Furthermore, α,β-Me-ATP-induced relaxation was suppressed by P2Y1 receptor antagonist MRS2179 (50 μmol/L) or P2Y13 receptor antagonist MRS2211 (100 μmol/L), and was abolished by co-application of the two antagonists, whereas 2-Me-S-ADP-induced relaxation was abolished by P2Y6 receptor antagonist MRS2578 (50 μmol/L). In addition, P2Y1 receptor antagonist MRS2500 (1 μmol/L) not only abolished α,β-Me-ATP-induced relaxation, but also suppressed 2-Me-S-ADP-induced relaxation. P2Y receptor agonist-induced transient relaxation of rat ileum smooth muscle strips is mediated predominantly by P2Y1 receptor, but also by P2Y6 and P2Y13 receptors, and involves PLC, IP3, Ca(2+) release and SK channel activation, but is independent of acetylcholine and NO release.
Comparing the sensitivity of chlorophytes, cyanobacteria, and diatoms to major-use antibiotics.
Guo, Jiahua; Selby, Katherine; Boxall, Alistair B A
2016-10-01
The occurrence of antibiotic residues in the aquatic environment is an emerging concern. In contrast to daphnia and fish, algae are known to be particularly sensitive to antibiotic exposure. However, to date, a systematic evaluation of the sensitivity of different algal species to antibiotics has not been performed. The aim of the present study was therefore to explore the sensitivity of a battery of algal species toward antibiotic exposures. The present study investigated the growth inhibition effects of 3 major-use antibiotics, tylosin, lincomycin, and trimethoprim, on 7 algal species from the chlorophyte, cyanobacteria, and diatom groups. Based on median effective concentration (EC50) values, cyanobacteria (EC50 = 0.095-0.13 μmol/L) were found to be the most sensitive group to lincomycin followed by chlorophytes (EC50 = 7.36-225.73 μmol/L) and diatoms (EC50 > 225.73 μmol/L). Cyanobacteria were also the most sensitive group to tylosin (EC50 = 0.09-0.092 μmol/L), but, for this compound, diatoms (EC50 = 1.33-5.7 μmol/L) were more sensitive than chlorophytes (EC50 = 4.14-81.2 μmol/L). Diatoms were most sensitive to trimethoprim (EC50 = 7.36-74.61 μmol/L), followed by cyanobacteria (EC50 = 315.78-344.45 μmol/L), and chlorophytes (EC50 > 344.45 μmol/L) for trimethoprim. Although these results partly support the current approach to regulatory environmental risk assessment (whereby cyanobacterial species are recommended for use with antibiotic compounds), they indicate that for some antibiotics this group might not be the most appropriate test organism. It is therefore suggested that environmental risk assessments consider data on 3 algal groups (chlorophytes, cyanobacteria, and diatoms) and use test species from these groups, which are consistently found to be the most sensitive (Pseudokirchneriella subcapitata, Anabaena flos-aquae, and Navicula pelliculosa). Environ Toxicol Chem 2016;35:2587-2596. © 2016 SETAC. © 2016 SETAC.
Energy transfer and 2.0 μm emission in Tm{sup 3+}/Ho{sup 3+} co-doped α-NaYF{sub 4} single crystals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Zhigang; Yang, Shuo; Xia, Haiping, E-mail: hpxcm@nbu.edu.cn
2016-04-15
Highlights: • Cubic NaYF{sub 4} single crystals co-doped with ∼1.90 mol% Tm{sup 3+} and various Ho{sup 3+} concentrations were grown by Bridgman method. • The maximum fluorescence lifetime was 23.23 ms for Tm{sup 3+} (1.90 mol%)/Ho{sup 3+} (3.89 mol%) co-doped α-NaYF{sub 4}. • The obtained energy transfer rate (W{sub ET}) and energy transfer efficiency (η) of Tm{sup 3+}:{sup 3}F{sub 4} are 1077 s{sup −1} and 95.0%, respectively. • The maximum emission cross section reached 1.06 × 10{sup −20} cm{sup 2}. - Abstract: Cubic NaYF{sub 4} single crystals co-doped with ∼1.90 mol% Tm{sup 3+} and various Ho{sup 3+} concentrations were grownmore » by Bridgman method. The energy transfer from Tm{sup 3+} to Ho{sup 3+} and the optimum fluorescence emission around 2.04 μm of Ho{sup 3+} ion were investigated based on the measured absorption spectra, emission spectra, emission cross section and decay curves under excitation of 800 nm LD. The emission intensity at 2.04 μm increased with the increase of Ho{sup 3+} concentration from 0.96 mol% to 3.89 mol% when the concentration of Tm{sup 3+} was held constantly at ∼1.90 mol%. Moreover, the maximum emission cross section reached 1.06 × 10{sup −20} cm{sup 2} and the maximum fluorescence lifetime was 23.23 ms for Tm{sup 3+}(1.90 mol%)/Ho{sup 3+}(3.89 mol%) co-doped one. According to the measured lifetime of Tm{sup 3+} single-doped and Tm{sup 3+}/Ho{sup 3+} co-doped samples, the maximum energy transfer efficiency of Tm{sup 3+}:{sup 3}F{sub 4} level was 95.0%. Analysis on the fluorescence dynamics indicated that electric dipole–dipole is dominant for the energy transfer from Tm{sup 3+} to Ho{sup 3+}.« less
NASA Astrophysics Data System (ADS)
Aucelio, Ricardo Q.; Carvalho, Juliana M.; Real, Juliana T.; Maqueira-Espinosa, Luis; Pérez-Gramatges, Aurora; da Silva, Andrea R.
2017-02-01
Flavonoids are polyphenols that help the maintenance of health, aiding the prevention of diseases. In this work, CdTe QDs coated with 3-mercaptopropionic acid (3MPA), with an average size of 2.7 nm, were used as photoluminescence probe for flavonoids in different conditions. The interaction between 14 flavonoids and QDs was evaluated in aqueous dispersions in the absence and in the presence of cetyltrimethylammonium bromide (CTAB). To establish a relationship between photoluminescence quenching and the concentration of flavonoids, the Stern-Volmer model was used. In the absence of CTAB, the linear ranges for quercetin, morin and rutin were from 5.0 × 10- 6 mol L- 1 to 6.0 × 10- 5 mol L- 1 and from 1.0 × 10- 5 mol L- 1 to 6.0 × 10- 4 mol L- 1 for kaempferol. The sensibility of the Stern-Volmer curves (Ks) indicated that quercetin interacts more strongly with the probe: Ks quercetin > Ks kaempferol > Ks rutin > Ks morin. The conjugation extension in the 3 rings, and the acidic hydroxyl groups (positions 3ʹand 4ʹ) in the B-ring enhanced the interaction with 3MPA-CdTe QDs. The other flavonoids do not interact with the probe at 10- 5 mol L- 1 level. In CTAB organized dispersions, Ks 3-hydroxyflavone > Ks 7-hydroxyflavone > Ks flavona > Ks rutin in the range from 1.0 × 10- 6 mol L- 1 to 1.2 × 10- 5 mol L- 1 for flavones and of 1.0 × 10- 6 mol L- 1 to 1.0 × 10- 5 mol L- 1 for rutin. Dynamic light scattering, conductometric measurements and microenvironment polarity studies were employed to elucidate the QDs-flavonoids interaction in systems containing CTAB. The quenching can be attributed to the preferential solubility of hydrophobic flavonoid in the palisade layer of the CTAB aggregates adsorbed on the surface of the 3MPA CdTe QDs.
NASA Technical Reports Server (NTRS)
Weinstein, Randi B.; Eleid, Noura; LeCesne, Catherine; Durando, Bianca; Crawford, Julie T.; Heffner, Michelle; Layton, Christle; O'Keefe, Matthew; Robinson, Jennifer; Rudinsky, Suzy;
2002-01-01
Analogs of human insulin have been used to discriminate between responses of metabolic and mitogenic (growth-related) pathways. This study compared the stimulatory effects of human insulin (HI) and 2 analogs (X2, B-Asp(9), B-Glu(27) and H2, A-His(8),B-His(4),B-Glu(10), B-His(27)) on glucose uptake and protein synthesis in rat soleus muscle in situ. Glucose uptake, estimated by intramuscular (IM) injection of 2-deoxy[1,2-3H]glucose with or without insulin, was maximally increased at 10(-6) mol/L for HI and X2 and 10(-7) mol/L for H2. HI had a larger effect (318%) than either X2 (156%) or H2 (124%). The half-maximal effect (ED(50)) values for HI, X2, and H2 were 3.3 x10(-8) mol/L, 1.7 x 10(-7) mol/L, and 1.6 x 10(-9) mol/L, respectively. Protein synthesis, estimated by protein incorporation of [(3)H]phenylalanine injected into muscles with or without insulin, was maximally increased at 10(-5) mol/L for HI and 10(-6) for X2 and H2. HI had a larger effect in stimulating protein synthesis (34%) than either X2 (25%) or H2 (19.8%). The ED(50) values for HI, X2, and H2 were 3.0 x 10(-7) mol/L, 3.2 x 10(-7) mol/L, and 1.0 x 10(-9) mol/L, respectively. The biological potency of each analog (ED(50)insulin/ED(50)analog) showed X2 to be less potent than HI for both glucose uptake (0.2) and protein synthesis (0.9), whereas H2 is more potent than HI with ratios of 20 and 300, respectively. These data suggest that this approach for studying insulin responsiveness in a single muscle in situ may be a useful tool for investigating insulin signaling in muscle in vivo. Copyright 2002, Elsevier Science (USA). All rights reserved.
NASA Astrophysics Data System (ADS)
Hulme, S. M.; Wheat, C. G.; Mottl, M. J.; Fryer, P.
2003-12-01
The Mariana forearc contains tens of seamounts up to 2 km high and 20-50 km in diameter. These seamounts were formed by serpentinite mud volcanism, sometimes in combination with uplift of serpentinized forearc mantle blocks, in which fluids driven off of the subducting slab infiltrated the overlying mantle and serpentinized the harzburgite and dunite rocks creating a density imbalance within the mantle. The resulting fluid-rock matrix flows along faults and exposes mantle-sourced serpentinite muds, blueschist facies metamorphosed mafic clasts, and slab-sourced fluids at the seafloor. The protrusion of these materials allows direct observation of active subduction zone components that are elsewhere buried beneath kilometers of rock and sediment. A multi-disciplinary survey of the Mariana Forearc was conducted in the spring of 2003 to study the biogeochemical properties of this mud volcanism. Seven different seamounts were sampled using shipboard and subsea coring techniques employing RV Thomas G. Thompson and ROV Jason II, respectively. Pore waters were extracted from these sediment cores and analyzed for several chemical constituents at sea. The measured values were consistent with preliminary work from 1997. Systematic trends in chemical composition of these high pH fluids (up to 12.3) are observed with distance from the trench (proxy for the depth to slab). These trends include low alkalinity and high Ca near the trench (e.g., Blue Moon Seamount; 0.26 mmol alkalinity/kg and 55 mmol Ca/kg), and high alkalinity and low Ca further from the trench (e.g., Big Blue Seamount; 69 mmol alkalinity/kg and 0.14 mmol Ca/kg) consistent with carbonate dissolution at the top of the plate between depths of 17 km and 22 km. Here we report results from trace element analyses that similarly show trends across the forearc region. For example, fluids upwelling at Baby Blue Seamount have; 58 μ mol Sr/kg, 31 μ mol Li/kg, 1.4 μ mol Rb/kg, 10 nmol Cs/kg, 0.2 μ mol Ba/kg, 0.1 μ mol Mo/kg, 0.6 nmol U/kg, and 5 nmol Y/kg. In contrast, fluids from Big Blue Seamount, only 23 km away, have; 10 μ mol Sr/kg, 0.7 μ mol Li/kg, 6 μ mol Rb/kg, 0.2 μ mol Cs/kg, 60 nmol Ba/kg, 0.1 μ mol Mo/kg, 0.2 μ mol U/kg, and 0.1 nmol Y/kg.Trace element analyses for a host of chemical species and for each of the sampled seamounts offer insight into the conditions and interactions currently occurring within the Mariana seismogenic zone.
Fifty years of Jaynes-Cummings physics
NASA Astrophysics Data System (ADS)
Greentree, Andrew D.; Koch, Jens; Larson, Jonas
2013-11-01
This special issue commemorates the 50th anniversary of the seminal paper published by E T Jaynes and F W Cummings [1], the fundamental model which they introduced and now carries their names, and celebrates the remarkable host of exciting research on Jaynes-Cummings physics throughout the last five decades. The Jaynes-Cummings model has been taking the prominent stance as the 'hydrogen atom of quantum optics' [2]. Generally speaking, it provides a fundamental quantum description of the simplest form of coherent radiation-matter interaction. The Jaynes-Cummings model describes the interaction between a single electromagnetic mode confined to a cavity, and a two-level atom. Energy is exchanged between the field and the atom, which leads directly to coherent population oscillations (Rabi oscillations) and superposition states (dressed states). Being exactly solvable, the Jaynes-Cummings model serves as a most useful toy model, and as such it is a textbook example of the physicists' popular strategy of simplifying a complex problem to its most elementary constituents. Thanks to the simplicity of the Jaynes-Cummings model, this caricature of coherent light-matter interactions has never lost its appeal. The Jaynes-Cummings model is essential when discussing experiments in quantum electrodynamics (indeed the experimental motivation of the Jaynes-Cummings model was evident already in the original paper, dealing as it does with the development of the maser), and it has formed the starting point for much fruitful research ranging from ultra-cold atoms to cavity quantum electrodynamics. In fact, Jaynes-Cummings physics is at the very heart of the beautiful experiments by S Haroche and D Wineland, which recently earned them the 2012 Nobel Prize in physics. Indeed, as with most significant models in physics, the model is invoked in settings that go far beyond its initial framework. For example, recent investigations involving multi-level atoms, multiple atoms [3, 4], multiple electromagnetic modes, arrays of coupled cavities [5-7], and optomechanical systems [8] have further enriched the physics of the Jaynes-Cummings model. From the early interests in masers and the consistent quantum description of radiation and atom-photon interaction, the Jaynes-Cummings model has evolved into a cornerstone of quantum state engineering [9]. The authors of this editorial had not been born when Jaynes and Cummings wrote their remarkable paper. It is, therefore, a special honour for us to be able to draw the reader's attention to the accompanying reminiscence contributed by Frederick Cummings where he gives us a glimpse of the early history of the Jaynes-Cummings model from his perspective [11]. By now, the original 1963 paper by Jaynes and Cummings has gathered numerous citations and, at the time of writing, the number of articles involving Jaynes-Cummings physics is approaching 15 000.1 This special issue does not attempt to review this impressive wealth of research. The interested reader, however, is urged to consult the definitive article by Shore and Knight [10] for a comprehensive review of the first 30 years of Jaynes-Cummings physics. The collection of 26 papers presented in this issue, showcases a snapshot of some of the most recent and continuing research devoted to Jaynes-Cummings physics. We begin our special issue with Professor Cumming's recollections [11]. We then have six papers on quantum information aspects of the Jaynes-Cummings model [12-17]. The next topic includes seven papers on the Dicke and generalized Jaynes-Cummings models [18-24], followed by six papers on circuit QED, which is one of the most important experimental frameworks for Jaynes-Cummings systems [25-30]. Finally, we have six papers on the extension to many cavities, the Jaynes-Cummings-Hubbard model [31-36]. The snapshot of research captured in this special issue illustrates the unifying language provided by the Jaynes-Cummings model, tying together research in a number of subfields in physics. Jaynes-Cummings physics started with the diagonalization of a 2 × 2 matrix, as Frederick Cummings points out. There is no doubt that this elegance of simplicity will continue to guide exciting new research in the decades to come. References [1] Jaynes E T and Cummings F W 1963 Comparison of quantum and semiclassical radiation theories with application to the beam maser Proc. IEEE 51 89 [2] Shore B W and Knight P L 2004 Physics and Probability: Essays in Honor of Edwin T Jaynes (Cambridge: Cambridge University Press) [3] Tavis M and Cummings F W 1968 Exact solution for an N -molecule-radiation-field Hamiltonian Phys. Rev. 170 379-84 [4] Tavis M and Cummings F W 1969 Approximate solutions for an N -molecule-radiation-field Hamiltonian Phys. Rev. 188 692-5 [5] Hartmann M J, Brandão F G S L and Plenio M B 2006 Strongly interacting polaritons in coupled arrays of cavities Nature Phys. 2 849-55 [6] Greentree A D, Tahan C, Cole J H and Hollenberg L C L 2006 Quantum phase transitions of light Nature Phys. 2 856-61 [7] Angelakis D G, Santos M F and Bose S 2007 Photon-blockade-induced Mott transitions and XY spin models in coupled cavity arrays Phys. Rev. A 76 031805(R) [8] Schwab K C and Roukes M L 2005 Putting mechanics into quantum mechanics Phys. Today 58 36-42 [9] Blatt R, Milburn G J and Lvovksy A 2013 The 20th anniversary of quantum state engineering J. Phys. B: At. Mol. Opt. Phys. 46 100201 [10] Shore B and Knight P L 1993 The Jaynes-Cummings model J. Mod. Opt. 40 1195-238 [11] Cummings F W 2013 J. Phys. B: At. Mol. Opt. Phys. 46 220202 [12] Arenz C 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224001 [13] Quesada N 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224002 [14] Everitt M 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224003 [15] Kitajima S 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224004 [16] Groves E 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224005 [17] Bougouffa S 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224006 [18] Braak D 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224007 [19] Emary C 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224008 [20] Miroshnychenko Y 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224009 [21] Dombi A 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224010 [22] Tavis M 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224011 [23] Grimsmo A 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224012 [24] Stenholm S I 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224013 [25] Kockum A F 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224014 [26] Larson J 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224015 [27] Larson J 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224016 [28] Agarwal S 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224017 [29] Deng W-W 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224018 [30] Leppaekangas J 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224019 [31] Schmidt S 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224020 [32] Schiro M 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224021 [33] Susa C 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224022 [34] del Valle E 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224023 [35] Correa B V 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224024 [36] Schetakis N 2013 J. Phys. B: At. Mol. Opt. Phys. 46 224025 1Number estimate based on a Google Scholar search.
Propane in nitrogen, 1000 μmol/mol
NASA Astrophysics Data System (ADS)
Konopelko, L. A.; Kustikov, Y. A.; Kolobova, A. V.; Pankratov, V. V.; Pankov, A. A.; Efremova, O. V.; Rozhnov, M. S.; Melnyk, D. M.; Petryshyn, P. V.; Levbarg, O. S.; Kisel, S. P.; Shpilnyi, S. A.; Yakubov, S. Ye; Bakovec, N. V.; Mironchik, A. M.; Aleksandrov, V. V.
2017-01-01
This article presents the report on the COOMET key comparison COOMET.QM-K111, which is linking to the appropriate CCQM comparison—CCQM-K111 'Propane in nitrogen 1000 μmol/mol'. CCQM-K111 was carried out in 2014-2016 and it was one of a series of key comparisons in the gas analysis area assessing core competences. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
1,5-Bis[1-(2,4-dihydroxyphenyl)ethylidene]carbonohydrazide dimethylformamide disolvate
He, Qing-Peng; Tan, Bo; Lu, Ze-Hua
2010-01-01
In the title compound, C17H18N4O5·2C3H7NO, two solvent molecules are linked to the main molecule via N—H⋯O and O—H⋯O hydrogen bonds, forming a hydrogen-bonded trimer. Intramolecular O—H⋯N hydrogen bonds influence the molecular conformation of the main molecule, and the two benzene rings form a dihedral angle of 10.55 (18)°. In the crystal, intermolecular O—H⋯O hydrogen bonds link hydrogen-bonded trimers into ribbons extending along the b axis. PMID:21589135
Garzón, A; Li, J; Flores, A; Casadesus, J; Stewart, V
1992-01-01
Selection for chlorate resistance yields mol (formerly chl) mutants with defects in molybdenum cofactor synthesis. Complementation and genetic mapping analyses indicated that the Klebsiella pneumoniae mol genes are functionally homologous to those of Escherichia coli and occupy analogous genetic map positions. Hypoxanthine utilization in other organisms requires molybdenum cofactor as a component of xanthine dehydrogenase, and thus most chlorate-resistant mutants cannot use hypoxanthine as a sole source of nitrogen. Surprisingly, the K. pneumoniae mol mutants and the mol+ parent grew equally well with hypoxanthine as the sole nitrogen source, suggesting that K. pneumoniae has a molybdenum cofactor-independent pathway for hypoxanthine utilization. PMID:1400180
pH-Sensitive Liposomes: Acid-Induced Liposome Fusion
NASA Astrophysics Data System (ADS)
Connor, Jerome; Yatvin, Milton B.; Huang, Leaf
1984-03-01
Sonicated unilamellar liposomes containing phosphatidylethanolamine and palmitoylhomocysteine fuse rapidly when the medium pH is lowered from 7 to 5. Liposome fusion was demonstrated by (i) mixing of the liposomal lipids as shown by resonance energy transfer, (ii) gel filtration, and (iii) electron microscopy. The pH-sensitive fusion of liposomes was observed only when palmitoylhomocysteine (>= 20 mol%) was present in the liposomes. The presence of phosphatidyl-ethanolamine in the liposomes greatly enhanced fusion whereas the presence of phosphatidylcholine inhibited fusion. During fusion of liposomes containing phosphatidylethanolamine and palmitoylhomocysteine (8:2, mol/mol), almost all of the encapsulated calcein was released. Inclusion of cholesterol (40 mol%) in the liposomes substantially decreased leakage without impairing fusion.
6-Chloro-3-phenethyl-2-thioxo-2,3-dihydroquinazolin-4(1H)-one
Hashim, Norhafizah Mohd; Osman, Hasnah; Rahim, Afidah Abdul; Yeap, Chin Sing; Fun, Hoong-Kun
2010-01-01
The asymmetric unit of the title quinazolinone compound, C16H13ClN2OS, consists of two crystallographically independent molecules, A and B. The dihedral angles between the quinazoline and benzene rings are 16.88 (6) and 32.34 (6)° for molecules A and B, respectively. In the crystal structure, molecules A and B are linked by two bifurcated intermolecular N—H⋯S and C—H⋯S hydrogen bonds. Pairs of molecules are further linked by C—H⋯O and C—H⋯Cl hydrogen bonds into a chain aligned approximately along [110]. PMID:21580754
The Dissociation Energies of CH4 and C2H2 Revisited
NASA Technical Reports Server (NTRS)
Partridge, Harry; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R. (Technical Monitor)
1995-01-01
The bond dissociation energies of CH4 and C2H2 and their fragments are investigated using basis set extrapolations and high levels of correlation. The computed bond dissociation energies (D(sub e)) are accurate to within 0.2 kcal/mol. The agreement with the experimental (D(sub 0)) values is excellent if we assume that the zero-point energy of C2H is 9.18 kcal/mol. The effect of core (1s) correlation on the bond dissociation energies of C-H bonds is shown to vary from 0.2 to 0.7 kcal/mol and that for C-C bonds varies from 0.4 to 2.2 kcal/mol.
Thermal Conductivity of Alumina-reinforced Zirconia Composites
NASA Technical Reports Server (NTRS)
Bansal, Narottam P.
2005-01-01
10-mol% yttria-stabilized zirconia (10SZ) - alumina composites containing 0-30 mol% alumina were fabricated by hot pressing at 1500 C in vacuum. Thermal conductivity was determined at various temperatures using a steady-state laser heat flux technique. Thermal conductivity of the composites increased with increase in alumina content. Composites containing 0, 5, and 10-mol% alumina did not show any change in thermal conductivity with temperature. However, those containing 20 and 30-mol% alumina showed a decrease in thermal conductivity with increase in temperature. The measured values of thermal conductivity were in good agreement with those calculated from the Maxwell-Eucken model where one phase is uniformly dispersed within a second major continuous phase.
A MRCC study of the isomerisation of cyclopropane
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lang, Jakub; Švaňa, Matej; Demel, Ondřej
2017-01-19
Mukherjee’s and Brillouin-Wigner multi-reference coupled cluster methods were used to study the isomerization of cyclopropane to propene through a trimethylene/propylidene diradicals. Main aim was to obtain high quality ab-initio data using advanced methods that treat both static and dynamic correlation in the involved species. The MkCCSD(T)/cc-pVQZ activation energy of cyclopropane isomerization via trimethylene is 65.6 kcal/mol, in a good agreement with experimental values in the range 60-65 kcal/mol. The MkCCSD(T)/cc-pV5Z adiabatic singlet-triplet gap in trimethylene is 0.6 kcal/mol, slightly higher than previous CASPT2 result -0.7 kcal/mol by Skancke et al.
N-(3-Chloro-1-methyl-1H-indazol-5-yl)-4-methylbenzenesulfonamide
Chicha, Hakima; Rakib, El Mostapha; Amiri, Ouafa; Saadi, Mohamed; El Ammari, Lahcen
2014-01-01
The asymmetric unit of the title compound, C15H14ClN3O2S, contains two independent molecules showing different conformations: in one molecule, the indazole ring system makes a dihedral angle of 51.5 (1)° with the benzene ring whereas in the other, the indazole unit is almost perpendicular to the benzene ring [dihedral angle 77.7 (1)°]. In the crystal, the molecules are linked by N—H⋯N and N—H⋯O hydrogen bonds, forming a set of four molecules linked in pairs about an inversion centre. PMID:24764895
Crankshaw, D L; Hetnarski, K; Wilkinson, C F
1979-01-01
1. NADPH-cytochrome c reductase was solubilized with bromelain and purified about 400-fold from sucrose/pyrophosphate-washed microsomal fractions from southern armyworm (Spodoptera eridania) larval midguts. 2. The enzyme has a mol.wt. of 70 035 +/- 1300 and contained 2 mol of flavin/mol of enzyme consisting of almost equimolar amounts of FMN and FAD. 3. Aerobic titration of the enzyme with NADPH caused the formation of a stable half-reduced state at 0.5 mol of NADPH/mol of flavin. 4. Kinetic analysis showed that the reduction of cytochrome c proceeded by a Bi Bi Ping Pong mechanism. 5. Apparent Km values for NADPH and cytochrome c and Ki values for NADP+ and 2'-AMP were considerably higher for the insect reductase than for the mammalian liver enzyme. 6. These are discussed in relation to possible differences in the active sites of the enzymes. Images Fig. 3. PMID:117798
Proton dependence of tobacco mosaic virus dissociation by pressure.
Santos, Jose L R; Bispo, Jose A C; Landini, Gustavo F; Bonafe, Carlos F S
2004-09-01
Tobacco mosaic virus (TMV) is an intensely studied model of viruses. This paper reports an investigation into the dissociation of TMV by pH and pressure up to 220 MPa. The viral solution (0.25 mg/ml) incubated at 277 K showed a significant decrease in light scattering with increasing pH, suggesting dissociation. This observation was confirmed by HPLC gel filtration and electron microscopy. The calculated volume change of dissociation (DeltaV) decreased (absolute value) from -49.7 ml/mol of subunit at pH 3.8 to -21.7 ml/mol of subunit at pH 9.0. The decrease from pH 9.0 to 3.8 caused a stabilization of 14.1 kJ/mol of TMV subunit. The estimated proton release calculated from pressure-induced dissociation curves was 0.584 mol H(+)/mol of TMV subunit. These results suggest that the degree of virus inactivation by pressure and the immunogenicity of the inactivated structures can be optimized by modulating the surrounding pH.
Veljković, Dušan Ž
2018-03-01
Energies of CH/O interactions between water molecule and polycyclic aromatic hydrocarbons with a different number of aromatic rings were calculated using ab initio calculations at MP2/cc-PVTZ level. Results show that an additional aromatic ring in structure of polycyclic aromatic hydrocarbons significantly strengthens CH/O interactions. Calculated interaction energies in optimized structures of the most stable tetracene/water complex is -2.27 kcal/mol, anthracene/water is -2.13 kcal/mol and naphthalene/water is -1.97 kcal/mol. These interactions are stronger than CH/O contacts in benzene/water complex (-1.44 kcal/mol) while CH/O contacts in tetracene/water complex are even stronger than CH/O contacts in pyridine/water complexes (-2.21 kcal/mol). Electrostatic potential maps for different polycyclic aromatic hydrocarbons were calculated and used to explain trends in the energies of interactions. Copyright © 2017 Elsevier Inc. All rights reserved.
(1E,4E)-1,5-Bis[4-(diethylamino)phenyl]penta-1,4-dien-3-one
Ruanwas, Pumsak; Chantrapromma, Suchada; Ghabbour, Hazem A.; Fun, Hoong-Kun
2014-01-01
There are two crystallograpically independent molecules in the asymmetric unit of the title bischalcone derivative, C25H32N2O. Both molecules are twisted with a dihedral angle between the two substituted benzene rings of 11.19 (16)° in one molecule and 14.40 (15)° in the other. The central penta-1,4-dien-3-one fragments make dihedral angles of 8.49 (17) and 4.26 (17)° with the two adjacent benzene rings in one molecule, whereas the corresponding values are 8.42 (16) and 6.18 (16)° in the other. In the crystal, molecules are arranged into chains along the c-axis direction. Adjacent chains are inter-linked by weak intermolecular C—H⋯O interactions. The crystal is further stabilized by C—H⋯π interactions. PMID:24860388
NASA Astrophysics Data System (ADS)
Wang, Xiaobing; Bai, Yang; Huang, Bo
2010-11-01
Low larval survival, poor settlement, and abnormal metamorphosis are major problems in seed production of donkey-ear abalone Haliotis asinina. We examined the effects of chemical cues including epinephrine, nor-epinephrine, and serotonin on larval survival, settlement, and metamorphosis in order to determine the possibility of using these chemicals to induce the problems. The results show that epinephrine could enhance metamorphosis rate at 10-6 mol/L only but higher concentrations (10-3-10-4 mol/L); and nor-epinephrine could inhibit the performance significantly, and serotonin could increase significantly the performance at a wide-range concentration (10-3-10-6 mol/L). Treatment with serotonin at 10-5 mol/L for 72 hours resulted in the highest settlement rate (42.2%) and survival rate (49.3%), while at 10-4 mol/L for 72 hours resulted in the highest metamorphosis rate (38.8%). Therefore, serotonin may be used as a fast metamorphosis inducer in abalone culture.
Devitrification properties of lead borate glasses
NASA Astrophysics Data System (ADS)
Bajaj, Anu; Khanna, Atul; Krishnan, K.; Aggarwal, Suresh K.
2013-06-01
Lead borate glasses containing 30 to 60 mol% PbO were prepared by melt quenching technique and devitrified by long duration heat treament in the supercooled region. Glasses crystallized on heating above their glass transition temperature, and the crystalline phases produced on devitrification were characterized by XRD and DSC analyses. Glass with 30 mol% PbO slowly formed a solid solution of Pb6B10O21 and Pb5B8O17 crystalline phases, while glasses with 40 and 50 mol% PbO formed a mixture of Pb6B10O21, Pb5B8O17 and the remanent glassy phase. Glasses with higher PbO concentration of 56 to 60 mol% devitrified completely and produced only Pb5B8O17 crystalline phase. Lead borate glasses with PbO concentration of 40 to 50 mol% showed maximum thermal stability against devitrification, the ease of crystallization of glasses was correlated with the fraction of tetrahedral borons in them.
Crystal structure of benzyl (E)-2-(3,4-di-meth-oxy-benzyl-idene)hydrazine-1-carbodi-thio-ate.
Tan, Yew-Fung; Break, Mohammed Khaled Bin; Tahir, M Ibrahim M; Khoo, Teng-Jin
2015-02-01
The title compound, C17H18N2O2S2, synthesized via a condensation reaction between S-benzyl di-thio-carbazate and 3,4-di-meth-oxy-benzaldehyde, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. Both mol-ecules have an L-shape but differ in the orientation of the benzyl ring with respect to the 3,4-di-meth-oxy-benzyl-idine ring, this dihedral angle is 65.59 (8)° in mol-ecule A and 73.10 (8)° in mol-ecule B. In the crystal, the A and B mol-ecules are linked via pairs of N-H⋯S hydrogen bonds, forming dimers with an R 2 (2)(8) ring motif. The dimers are linked via pairs of C-H⋯O hydrogen bonds, giving inversion dimers of dimers. These units are linked by C-H⋯π inter-actions, forming ribbons propagating in the [100] direction.
Crystal structure of 3-hydroxymethyl-1,2,3,4-tetrahydroisoquinolin-1-one
Caracelli, Ignez; Hino, Camila Lury; Zukerman-Schpector, Julio; Biaggio, Francisco Carlos; Tiekink, Edward R. T.
2015-01-01
In the title compound, C10H11NO2, two independent but virtually superimposable molecules, A and B, comprise the asymmetric unit. The heterocyclic ring in each molecule has a screw-boat conformation, and the methylhydroxyl group occupies a position to one side of this ring with N—C—C—O torsion angles of −55.30 (15) (molecule A) and −55.94 (16)° (molecule B). In the crystal, O—H⋯O and N—H⋯O hydrogen bonding leads to 11-membered {⋯HNCO⋯HO⋯HNC2O} heterosynthons, involving three different molecules, which are edge-shared to generate a supramolecular chain along the a axis. Interactions of the type C—H⋯O provide additional stability to the chains, and link these into a three-dimensional architecture. PMID:26396795
Liu, Shuli; Zhang, Guangming; Li, Jianzheng; Li, Xiangkun; Zhang, Jie
2016-01-01
This work investigated the effects of eight metal ions on Rhodopseudomonas palustris growth and 5-aminolevulinic acid (ALA) yield in wastewater treatment. Results show that metal ions (Mg(2+) of 15 mmol/L, Fe(2+) of 400 μmol/L, Co(2+) of 4 μmol/L, Ni(2+) of 8 μmol/L and Zn(2+) of 4 μmol/L) could effectively improve the chemical oxygen demand (COD) removal, Rp. palustris biomass and ALA yield. The highest ALA yield of 13.1 mg/g-biomass was achieved with Fe(2+) of 400 μmol/L. ALA yields were differentially increased under different metal ions in the following order: Fe(2+) group > Mg(2+) group > Co(2+) group = Ni(2+) group > Zn(2+) group = Mo(2+) group > control. Cu(2+) and Mn(2+) inhibited Rp. palustris growth and ALA production. Mechanism analysis revealed that metal ions changed ALA yields by influencing the activities of ALA synthetase and ALA dehydratase.
Metabolic stability of new anticonvulsants in body fluids and organ homogenates.
Marszałek, Dorota; Goldnik, Anna; Pluciński, Franciszek; Mazurek, Aleksander P; Jakubiak, Anna; Lis, Ewa; Tazbir, Piotr; Koziorowska, Agnieszka
2012-01-01
The stability as a function of time of compounds with established anticonvulsant activity: picolinic acid benzylamide (Pic-BZA), picolinic acid 2-fluorobenzylamide (Pic-2-F-BZA), picolinic acid 3-fluorobenzylamide (Pic-3-F-BZA), picolinic acid 4-fluorobenzylamide (Pic-4-F-BZA) and picolinic acid 2-methylbenzylamide (Pic-2-Me-BZA) in body fluids and homogenates of body organs were determined after incubation. It was found that they decompose relatively rapidly in liver and kidney and are stable against enzymes present in body fluids and some organs. These results are consistent with the bond strength expressed as total energy of amide bonds (calculated by quantum chemical methods) in the studied anticonvulsants. The calculated values of the amide bond energy are: 199.4 kcal/mol, 200.2 kcal/mol, 207.5 kcal/mol, 208.4 kcal/mol and 198.2 kcal/mol, respectively. The strength of the amide bonds in the studied anticonvulsants correctly reflects their stability in liver or kidney.
Understanding the new HbA1c units for the diagnosis of Type 2 diabetes.
Braatvedt, Geoff D; Cundy, Tim; Crooke, Michael; Florkowski, Chris; Mann, Jim I; Lunt, Helen; Jackson, Rod; Orr-Walker, Brandon; Kenealy, Timothy; Drury, Paul L
2012-09-21
In New Zealand laboratories the measurement of glycated haemoglobin (HbA1c) for diagnosis of diabetes is now only reported in SI units of mmol/mol. HbA1c is now recommended as the preferred test to diagnose diabetes in most circumstances. The requirement for a second positive test in asymptomatic individuals is retained. An HbA1c greater than and equal to 50 mmol/mol (repeated on a second occasion in asymptomatic patients) is diagnostic of diabetes and a value less than and equal to 40 mmol/mol represents normal glucose tolerance. For patients with an initial HbA1c result of 41-49 mmol/mol, cardiovascular risk assessment and lifestyle interventions are recommended with repeat HbA1c screening in 6-12 months. For patients whose HbA1c is less than and equal to 40 mmol/mol, repeat screening (including for CVD risk) at intermittent intervals is recommended as per published guidelines.
N-(1-Allyl-1H-indazol-5-yl)-4-methylbenzenesulfonamide
Chicha, Hakima; Rakib, El Mostapha; Abderrafia, Hafid; Saadi, Mohamed; El Ammari, Lahcen
2013-01-01
The asymmetric unit of the title compound, C17H17N3O2S, contains two independent molecules linked by an N—H⋯O hydrogen bond. The molecules show different conformations. In the first molecule, the fused five- and six-membered ring system is almost perpendicular to the plane through the atoms forming the allyl group, as indicated by the dihedral angle of 85.1 (4)°. The dihedral angle with the methylbenzenesulfonamide group is 78.8 (1)°. On the other hand, in the second molecule, the dihedral angles between the indazole plane and the allyl and methylbenzenesulfonamide groups are 80.3 (3) and 41.5 (1)°, respectively. In the crystal, molecules are further linked by N—H⋯N and C—H⋯O hydrogen bonds, forming a three-dimensional network. PMID:24454264
Spectroscopic analysis on the resveratrol-DNA binding interactions at physiological pH
NASA Astrophysics Data System (ADS)
Zhang, Shufang; Sun, Xuejun; Jing, Zhihong; Qu, Fengli
2011-11-01
The interaction of resveratrol with calf thymus deoxyribonucleic acid (ctDNA) under physiological conditions (Tris-HCl buffer solutions, pH 7.4) was studied by spectroscopy, fluorescence spectroscopy and viscosity measurement method, respectively. Results indicated that a complex of resveratrol with ctDNA was formed with a binding constant of K17 °C = 5.49 × 10 3 L mol -1 and K37 °C = 1.90 × 10 4 L mol -1. The fluorescence quenching mechanism of acridine orange (AO)-ctDNA by resveratrol was shown to be a static quenching type. The thermodynamic parameters of the complex were calculated by a double reciprocal method: ΔHms=4.64×10 J mol, ΔSms=231.8 J K mol and ΔGms=-2.54×10 J mol (37 °C). Spectroscopic techniques together with viscosity determination provided evidences of intercalation mode of binding for the interaction between resveratrol and ctDNA.
Epoxidation of cottonseed oil by aqueous hydrogen peroxide catalysed by liquid inorganic acids.
Dinda, Srikanta; Patwardhan, Anand V; Goud, Vaibhav V; Pradhan, Narayan C
2008-06-01
The kinetics of epoxidation of cottonseed oil by peroxyacetic acid generated in situ from hydrogen peroxide and glacial acetic acid in the presence of liquid inorganic acid catalysts were studied. It was possible to obtain up to 78% relative conversion to oxirane with very less oxirane cleavage by in situ technique. The rate constants for sulphuric acid catalysed epoxidation of cottonseed oil were in the range 0.39-5.4 x 10(-6)L mol(-1)s(-1) and the activation energy was found to be 11.7 kcal mol(-1). Some thermodynamic parameters such as enthalpy, entropy, and free energy of activation were determined to be of 11.0 kcal mol(-1), -51.4 cal mol(-1)K(-1) and 28.1 kcal mol(-1), respectively. The order of effectiveness of catalysts was found to be sulphuric acid>phosphoric acid>nitric acid>hydrochloric acid. Acetic acid was found to be superior to formic acid for the in situ cottonseed oil epoxidation.
Building Cultural Capability for Full-Spectrum Operations
2008-01-01
Mol, Born, Willemsen, & Van der Molen , 2005; Caligiuri & Day, 2000). In addition to these broad traits, antecedents to cross-cultural competence...510-517. 18 Mol, S. T., Born, M. P., Willemsen, M. E., & Van Der Molen , H. T. (2005). Predicting expatriate job performance for selection purposes: A...et al., 2003). In addition, self-regulation has been shown to be critical for adjustment (Matsumoto et al., 2003; van Oudenhoven, Mol, & Van der Zee
Liu, Yan-Ming; Cao, Jun-Tao; Zheng, Yan-Li; Chen, Yong-Hong
2008-07-01
A new and sensitive method for the determination of norepinephrine (NE), synephrine, and isoproterenol was developed by CE separation and indirect electrochemiluminescence detection (ECL) based on their quenching effects on the tris(2,2'-bipyridyl)-ruthenium(II)/tripropylamine (TPA) system. The conditions for CE separation and ECL detection were investigated in detail. Under the optimum conditions, the three analytes were well separated within 9 min. The LODs (S/N = 3) in standard solution are 2.6 x 10(-8) mol/L for NE, 6.6 x 10(-9) mol/L for synephrine and 8.4 x 10(-8) mol/L for isoproterenol, respectively. The precisions of intraday and interday are less than 4.4 and 6.1%, respectively. The LOQs (S/N = 10) in real human urine samples are 2.6 x 10(-7) mol/L for NE, 8.8 x 10(-8 ) mol/L for synephrine, and 8.8 x 10(-7) mol/L for isoproterenol, respectively. The applicability of the proposed method was illustrated in the determination of 20 human urine samples from diabetic patients and healthy persons. The results obtained indicated that the level of NE in patients (mean value 0.41 micromol/L) was higher than that in healthy persons (mean value 0.24 micromol/L).
Extraction of Proanthocyanidins and Anthocyanins from Grape Skin by Using Ionic Liquids
2017-01-01
Summary In this study, eight different types of imidazolium-based ionic liquids (ILs) were applied as new solvents in the extraction of flavonoids from grape skin, and compared to the conventional organic solvent extraction that was not reported earlier. The structure of anions, cations and concentration of ILs significantly affected extraction yields. The highest mass fractions of proanthocyanidins and anthocyanins were obtained with 2.5 mol/L of 1-butyl-3-methylimidazolium bromide [C4mim][Br] and 2.5 mol/L of 1-ethyl-3-methylimidazolium bromide [C2mim][Br], respectively. The studied ILs provided an excellent preliminary result in the extraction of anthocyanins. Significantly higher mass fractions of total and all free anthocyanins were extracted with 2.5 mol/L of [C2mim][Br] and 2.5 mol/L of 1-methylimidazolium hydrogen sulfate [mim][HSO4] than with conventional solvent with the exception of anthocyanin-3-O-acetylmonoglucosides in the latter. On the other hand, 2.5 mol/L of [C4mim][Br] and 2.5 mol/L of 1-(4-sulfobutyl)-3-methylimidazolium hydrogen sulfate [sC4mim][HSO4] showed significantly higher selectivity towards anthocyanin-3-O-acetylmonoglucosides and anthocyanin-3-(6-O-p-coumaroyl)monoglucosides. PMID:29089857
Pérez-Maldonado, Iván N; Trejo-Acevedo, Antonio; Pruneda-Alvarez, Lucia Guadalupe; Gaspar-Ramirez, Octavio; Ruvalcaba-Aranda, Selene; Perez-Vazquez, Francisco Javier
2013-11-01
The aim of this study was to evaluate the DDT, DDE, and 1-hydroxypyrene exposure levels of children living in communities located in southeastern Mexico. The study communities were Lacanja and Victoria in Chiapas state and Ventanilla in Oaxaca state. Children living in Lacanja had total blood DDT levels (mean ± SD, 29,039.6 ± 11,261.4 ng/g lipid) that were significantly higher than those of children in Victoria (10,220.5 ± 7,893.1 ng/g lipid) and Ventanilla (11,659.7 ± 6,683.7 ng/g lipid). With respect to the 1-hydroxypyrene levels in urine samples, the levels in Lacanja (4.8 ± 4.1 μg/L or 4.5 ± 3.9 μmol/mol creatinine) and Victoria (4.6 ± 3.8 μg/L or 3.9 ± 3.0 μmol/mol Cr) were significantly higher than levels found in Ventanilla (3.6 ± 1.4 μg/L or 2.5 ± 0.5 μmol/mol Cr). In conclusion, our data indicate high levels of exposure in children living in the communities studied in this work. The evidence found in this study could be further used as a trigger to revisit local policies on environmental exposures.
NASA Astrophysics Data System (ADS)
Cheng, Jun; Hu, Leiqing; Li, Yannan; Liu, Jianzhong; Zhou, Junhu; Cen, Kefa
2017-07-01
To research effects of CO2 absorption capacity and type of CO2 absorbent on the CO2 separation and free-volume properties of facilitated transport membranes, two types of CO2 absorbents, namely monoethanolamine (MEA) and ionic liquids (ILs:[P66614][Triz] and [P66614][2-Op]), were adopted. The CO2 absorption capacities of MEA, [P66614][Triz] and [P66614][2-Op] were about 0.561 mol CO2 per mol, 0.95 mol CO2 per mol and 1.60 mol CO2 per mol, respectively. All mean free-volume hole radiuses of membranes decreased after blending CO2 absorbents. After polymer membrane blended with two ILs, number of free-volume hole increased, resulting in modest increase of the fractional free volume. Both CO2 permeability and selectivity increased after blending MEA and ILs. The increasing range of CO2 permeability corresponded with CO2 absorption capacity of CO2 absorbents, and membrane blending with [P66614][2-Op] showed the highest CO2 permeability of 672.1 Barrers at 25 °C. Pebax/PEGDME membrane blending with MEA obtained the highest CO2/H2 and CO2/CH4 selectivity at 17.8 and 20.5, respectively.
Reaction mechanism of guanidinoacetate methyltransferase, concerted or step-wise.
Zhang, Xiaodong; Bruice, Thomas C
2006-10-31
We describe a quantum mechanics/molecular mechanics investigation of the guanidinoacetate methyltransferase catalyzed reaction, which shows that proton transfer from guanidinoacetate (GAA) to Asp-134 and methyl transfer from S-adenosyl-L-methionine (AdoMet) to GAA are concerted. By self-consistent-charge density functional tight binding/molecular mechanics, the bond lengths in the concerted mechanism's transition state are 1.26 A for both the OD1 (Asp-134)-H(E) (GAA) and H(E) (GAA)-N(E) (GAA) bonds, and 2.47 and 2.03 A for the S8 (AdoMet)-C9 (AdoMet) and C9 (AdoMet)-N(E) (GAA) bonds, respectively. The potential-energy barrier (DeltaE++) determined by single-point B3LYP/6-31+G*//MM is 18.9 kcal/mol. The contributions of the entropy (-TDeltaS++) and zero-point energy corrections Delta(ZPE)++ by normal mode analysis are 2.3 kcal/mol and -1.7 kcal/mol, respectively. Thus, the activation enthalpy of this concerted mechanism is predicted to be DeltaH++ = DeltaE++ plus Delta(ZPE)++ = 17.2 kcal/mol. The calculated free-energy barrier for the concerted mechanism is DeltaG++ = 19.5 kcal/mol, which is in excellent agreement with the value of 19.0 kcal/mol calculated from the experimental rate constant (3.8 +/- 0.2.min(-1)).
The compressibility of cubic white and orthorhombic, rhombohedral, and simple cubic black phosphorus
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clark, Simon M; Zaug, Joseph
2010-03-10
The effect of pressure on the crystal structure of white phosphorus has been studied up to 22.4 GPa. The ?alpha phase was found to transform into the alpha' phase at 0.87 +- 0.04 GPa with a volume change of 0.1 +- 0.3 cc/mol. A fit of a second order Birch- Murnaghan equation to the data gave Vo = 16.94 ? 0.08 cc/mol and Ko = 6.7 +- 0.5 GPa for the alpha phase and Vo = 16.4 +- 0.1 cc/mol and Ko = 9.1 +- 0.3 GPa for the alpha' phase. The alpha' phase was found to transform to themore » A17 phase of black phosphorus at 2.68 +- 0.34 GPa and then with increasing pressure to the A7 and then simple cubic phase of black phosphorus. A fit of a second order Birch-Murnaghan equation to our data combined with previous measurements gave Vo = 11.43 +- 0.05 cc/mol and Ko = 34.7 +- 0.5 GPa for the A17 phase, Vo = 9.62 +- 0.01 cc/mol and Ko = 65.0 +- 0.6 GPa for the A7 phase and , Vo = 9.23 +- 0.01 cc/mol and Ko = 72.5 +- 0.3 GPa for the simple cubic phase.« less
MAGNETIC BEHAVIOR OF IRON IONS IN THE P2O5·CaO GLASS MATRIX
NASA Astrophysics Data System (ADS)
ARDELEAN, I.; ANDRONACHE, C.; PǍŞCUŢǍ, P.
The temperature dependence of the magnetic susceptibility of xFe2O3·(100-x)-[P2O5·CaO] glasses with 0
Xue, Zhenzhen; Kotani, Akira; Yang, Bin; Hakamata, Hideki
2018-05-31
A two-channel liquid chromatography with electrochemical detection system (2LC-ECD) was newly designed for the simultaneous determination of magnolosides A, B, F, H, and L in the first channel and other magnolosides D and M in the second channel, respectively. Peak heights had linear relationships to the magnoloside concentrations in a range of 0.02-16 μmol/L for H, 0.01-12 μmol/L for A, 0.02-12 μmol/L for F and L, 0.01-8 μmol/L for B, 0.002-6 μmol/L for D, and 0.002-4 μmol/L for M, respectively. Seven magnolosides in magnoliae officinalis cortex (MOC) were determined by the 2LC-ECD, and the obtained quantitative profiles of magnolosides were applied to the discrimination between the MOC samples harvested from Hubei and Sichuan (called Chuan po) and from Zhejiang and Fujian (called Wen po). By principal component analysis (PCA) and supervised partial least squares discriminant analysis (PLS-DA) based on the quantitative profiles of the magnolosides, Chuan po were clearly discriminated from Wen po on the plots obtained from our multivariable analyses. Copyright © 2018 Elsevier B.V. All rights reserved.
Kinetic study of hydrolysis of xylan and agricultural wastes with hot liquid water.
Zhuang, Xinshu; Yuan, Zhenhong; Ma, Longlong; Wu, Chuangzhi; Xu, Mingzhong; Xu, Jingliang; Zhu, Shunni; Qi, Wei
2009-01-01
We investigated the kinetics of hot liquid water (HLW) hydrolysis over a 60-min period using a self-designed setup. The reaction was performed within the range 160-220 degrees C, under reaction conditions of 4.0 MPa, a 1:20 solid:liquid ratio (g/mL), at 500 rpm stirring speed. Xylan was chosen as a model compound for hemicelluloses, and two kinds of agricultural wastes-rice straw and palm shell-were used as typical feedstocks representative of herbaceous and woody biomasses, respectively. The hydrolysis reactions for the three kinds of materials followed a first-order sequential kinetic model, and the hydrolysis activation energies were 65.58 kJ/mol for xylan, 68.76 kJ/mol for rice straw, and 95.19 kJ/mol for palm shell. The activation energies of sugar degradation were 147.21 kJ/mol for xylan, 47.08 kJ/mol for rice straw and 79.74 kJ/mol for palm shell. These differences may be due to differences in the composition and construction of the three kinds of materials. In order to reduce the decomposition of sugars, the hydrolysis time of biomasses such as rice straw and palm shell should be strictly controlled.
Seitz, Christian G; Zhang, Huaiyu; Mo, Yirong; Karty, Joel M
2016-05-06
Contributions by resonance and inductive effects toward the net activation barrier were determined computationally for the gas-phase SN2 reaction between the acetaldehyde enolate anion and methyl fluoride, for both O-methylation and C-methylation, in order to understand why this reaction favors O-methylation. With the use of the vinylogue extrapolation methodology, resonance effects were determined to contribute toward increasing the size of the barrier by about 9.5 kcal/mol for O-methylation and by about 21.2 kcal/mol for C-methylation. Inductive effects were determined to contribute toward increasing the size of the barrier by about 1.7 kcal/mol for O-methylation and 4.2 kcal/mol for C-methylation. Employing our block-localized wave function methodology, we determined the contributions by resonance to be 12.8 kcal/mol for O-methylation and 22.3 kcal/mol for C-methylation. Thus, whereas inductive effects have significant contributions, resonance is the dominant factor that leads to O-methylation being favored. More specifically, resonance serves to increase the size the barrier for C-methylation significantly more than it does for O-methylation.
Cabello, Juan; Toledo-Cervantes, Alma; Sánchez, León; Revah, Sergio; Morales, Marcia
2015-04-01
This paper evaluates the effect of the irradiance, pH and temperature on the photosynthetic activity (PA) of Scenedesmus obtusiusculus under N-replete and N-deplete conditions through oxygen measurements. The highest PA values were 160 mgO2 gb(-1) h(-1) at 620 μmol m(-2) s(-1), 35 °C and pH of 8 under N-replete conditions and 3.3 mgO2 gb(-1) h(-1) at 100 μmol m(-2) s(-1), 28.5 °C and pH of 5.5 for N-deplete conditions. Those operation conditions were tested in a flat-panel photobioreactor. The biomass productivity was 0.97 gb L(-1) d(-1) under N-replete conditions with a photosynthetic efficiency (PE) of 4.4% yielding 0.85 gb mol photon(-1). Similar biomass productivity was obtained under N-deplete condition; and the lipid productivity was 0.34 gL L(-1) d(-1) with a PE of 7.8% yielding 0.39 gL mol photon(-1). The apparent activation and deactivation energies were 16.1 and 30 kcal mol(-1), and 11.9 and 15.3 kcal mol(-1), for N-replete and N-deplete conditions, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.
Thin Layer Drying Kinetics of By-Products from Olive Oil Processing
Montero, Irene; Miranda, Teresa; Arranz, Jose Ignacio; Rojas, Carmen Victoria
2011-01-01
The thin-layer behavior of by-products from olive oil production was determined in a solar dryer in passive and active operation modes for a temperature range of 20–50 °C. The increase in the air temperature reduced the drying time of olive pomace, sludge and olive mill wastewater. Moisture ratio was analyzed to obtain effective diffusivity values, varying in the oil mill by-products from 9.136 × 10−11 to 1.406 × 10−9 m2/s in forced convection (ma = 0.22 kg/s), and from 9.296 × 10−11 to 6.277 × 10−10 m2/s in natural convection (ma = 0.042 kg/s). Diffusivity values at each temperature were obtained using the Fick’s diffusion model and, regardless of the convection, they increased with the air temperature. The temperature dependence on the effective diffusivity was determined by an Arrhenius type relationship. The activation energies were found to be 38.64 kJ/mol, 30.44 kJ/mol and 47.64 kJ/mol for the olive pomace, the sludge and the olive mill wastewater in active mode, respectively, and 91.35 kJ/mol, 14.04 kJ/mol and 77.15 kJ/mol in natural mode, in that order. PMID:22174639
Paulechka, Yauheni U; Kabo, Andrey G; Blokhin, Andrey V
2009-11-05
The enthalpy of the 1-butyl-3-methylimidazolium bromide [C(4)mim]Br ionic liquid synthesis reaction 1-methylimidazole (liq) + 1-bromobutane (liq) --> [C(4)mim]Br (liq) was determined in a homemade small-volume isoperibol calorimeter to be Delta(r)H degrees (298) = -87.7 +/- 1.6 kJ x mol(-1). The activation energy for this reaction in a homogeneous system E(A) = 73 +/- 4 kJ x mol(-1) was found from the results of calorimetric measurements. The formation enthalpies for the crystalline and liquid [C(4)mim]Br were determined from the calorimetric data: Delta(f)H degrees (298)(cr) = -178 +/- 5 kJ x mol(-1) and Delta(f)H degrees (298)(liq) = -158 +/- 5 kJ x mol(-1). The ideal-gas formation enthalpy of this compound Delta(f)H degrees (298)(g) = 16 +/- 7 kJ x mol(-1) was calculated using the methods of quantum chemistry and statistical thermodynamics. The vaporization enthalpy of [C(4)mim]Br, Delta(vap)H degrees (298) = 174 +/- 9 kJ x mol(-1), was estimated from the experimental and calculated formation enthalpies. It was demonstrated that vapor pressure of this ionic liquid cannot be experimentally determined.
Vogan, Patrick J; Frohlich, Michael W; Sage, Rowan F
2007-10-01
We demonstrate for the first time the presence of species exhibiting C3-C4 intermediacy in Heliotropium (sensu lato), a genus with over 100 C3 and 150 C4 species. CO2 compensation points (Gamma) and photosynthetic water-use efficiencies (WUEs) were intermediate between C3 and C4 values in three species of Heliotropium: Heliotropium convolvulaceum (Gamma = 20 micromol CO2 mol(-1) air), Heliotropium racemosum (Gamma = 22 micromol mol(-1)) and Heliotropium greggii (Gamma = 17 micromol mol(-1)). Heliotropium procumbens may also be a weak C3-C4 intermediate based on a slight reduction in Gamma (48.5 micromol CO2 mol(-1)) compared to C3Heliotropium species (52-60 micromol mol(-1)). The intermediate species H. convolvulaceum, H. greggii and H. racemosum exhibited over 50% enhancement of net CO2 assimilation rates at low CO2 levels (200-300 micromol mol(-1)); however, no significant differences in stomatal conductance were observed between the C3 and C3-C4 species. We also assessed the response of Gamma to variation in O2 concentration for these species. Heliotropium convolvulaceum, H. greggii and H. racemosum exhibited similar responses of Gamma to O2 with response slopes that were intermediate between the responses of C3 and C4 species below 210 mmol O2 mol(-1) air. The presence of multiple species displaying C3-C4 intermediate traits indicates that Heliotropium could be a valuable new model for studying the evolutionary transition from C3 to C4 photosynthesis.
Desorption Kinetics of H2O from Cab-O-Sil-M-7D and Hi-Sil-233 Silica Particles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dinh, L.; Balooch, M.; LeMay, J.D.
2000-01-26
Temperature programmed desorption (TPD) was performed at temperatures up to 850K on Cab-O-Sil-M-7D and Hi-Sil-233 silica particles. Physisorbed water molecules on both types of silica had activation energies in the range of 9-14.5 kcal/mol. However, the activation energies of desorption for chemisorbed water varied from {approx} 19 kcal/mol to > 59 kcal/mol for Cab-O-Sil-M-7D, and {approx} 23-37 kcal/mol for Hi-Sil-233. Our results suggest that physisorbed water can be effectively pumped away at room temperature (or preferably at 320 K) in a matter of hours. Chemisorbed water with high activation energies of desorption (>30 kcal/mol) will not escape the silica surfacesmore » in 100 years even at 320 K, while a significant amount of the chemisorbed water with medium activation energies (19-26 kcal/mol) will leave the silica surfaces in that time span. Most of the chemisorbed water with activation energies < 30 kcal/mol can be pumped away in a matter of days in a good vacuum environment at 500 K. We had previously measured about 0.1-0.4 wt. % of water in M9787 polysiloxane formulations containing {approx} 21% Cab-O-Sil-M-7D and {approx} 4% Hi-Sil-233. Comparing present results with these formulations, we conclude that absorbed H{sub 2}O and Si-OH bonds on the silica surfaces are the major contributors to water outgassing from M97 series silicones.« less
Tilney, L G
1975-02-01
When Limulus sperm are induced to undergo the acrosomal reaction, a process, 50 mum in length, is generated in a few seconds. This process rotates as it elongates; thus the acrosomal process literally screws through the jelly of the egg. Within the process is a bundle of filaments which before induction are coiled up inside the sperm. The filament bundle exists in three stable states in the sperm. One of the states can be isolated in pure form. It is composed of only three proteins whose molecular weights (mol wt) are 43,000, 55,000, and 95,000. The 43,000 mol wt protein is actin, based on its molecular weight, net charge, morphology, G-F transformation, and heavy meromyosin (HMM) binding. The 55,000 mol wt protein is in equimolar ratio to actin and is not tubulin, binds tenaciously to actin, and inhibits HMM binding. Evidence is presented that both the 55,000 mol wt protein and the 95,000 mol wt protein (possibly alpha-actinin) are also present in Limulus muscle. Presumably these proteins function in the sperm in holding the actin filaments together. Before the acrosomal reaction, the actin filaments are twisted over one another in a supercoil; when the reaction is completed, the filaments lie parallel to each other and form an actin paracrystal. This change in their packing appears to give rise to the motion of the acrosomal process and is under the control of the 55,000 mol wt protein and the 95,000 mol wt protein.
Gelain, Daniel Pens; Pasquali, Matheus Augusto de Bittencourt; Caregnato, Fernanda Freitas; Castro, Mauro Antonio Alves; Moreira, José Claudio Fonseca
2012-04-01
Toxicity of retinol (vitamin A) has been previously associated with apoptosis and/or cell malignant transformation. Thus, we investigated the pathways involved in the induction of proliferation, deformation and proliferative focus formation by retinol in cultured Sertoli cells of rats. Sertoli cells were isolated from immature rats and cultured. The cells were subjected to a 24-h treatment with different concentrations of retinol. Parameters of oxidative stress and cytotoxicity were analyzed. The effects of the p38 inhibitor SB203580 (10 μmol/L), the JNK inhibitor SP600125 (10 μmol/L), the Akt inhibitor LY294002 (10 μmol/L), the ERK inhibitor U0126 (10 μmol/L) the pan-PKC inhibitor Gö6983 (10 μmol/L) and the PKA inhibitor H89 (1 μmol/L) on morphological and proliferative/transformation-associated modifications were studied. Retinol (7 and 14 μmol/L) significantly increases the reactive species production in Sertoli cells. Inhibition of p38, JNK, ERK1/2, Akt, and PKA suppressed retinol-induced [(3)H]dT incorporation into the cells, while PKC inhibition had no effect. ERK1/2 and p38 inhibition also blocked retinol-induced proliferative focus formation in the cells, while Akt and JNK inhibition partially decreased focus formation. ERK1/2 and p38 inhibition hindered transformation-associated deformation in retinol-treated cells, while other treatments had no effect. Our results suggest that activation of multiple kinases is responsible for morphological and proliferative changes associated to malignancy development in Sertoli cells by retinol at the concentrations higher than physiological level.
A density functional for core-valence correlation energy
NASA Astrophysics Data System (ADS)
Ranasinghe, Duminda S.; Frisch, Michael J.; Petersson, George A.
2015-12-01
A density functional, ɛCV-DFT(ρc, ρv), describing the core-valence correlation energy has been constructed as a linear combination of ɛLY Pcorr(ρc), ɛV WN5corr(ρc, ρv), ɛPBEcorr(ρc, ρv), ɛSlaterex(ρc, ρv), ɛHCTHex(ρc, ρv), ɛHFex(ρc, ρv), and F CV -DFT (" separators=" N i , Z i ) , a function of the nuclear charges. This functional, with 6 adjustable parameters, reproduces (±0.27 kcal/mol rms error) a benchmark set of 194 chemical energy changes including 9 electron affinities, 18 ionization potentials, and 167 total atomization energies covering the first- and second-rows of the periodic table. This is almost twice the rms error (±0.16 kcal/mol) obtained with CCSD(T)/MTsmall calculations, but less than half the rms error (±0.65 kcal/mol) obtained with MP2/GTlargeXP calculations, and somewhat smaller than the rms error (±0.39 kcal/mol) obtained with CCSD/MTsmall calculations. The largest positive and negative errors from ɛCV-DFT(ρc, ρv) were 0.88 and -0.75 kcal/mol with the set of 194 core-valence energy changes ranging from +3.76 kcal/mol for the total atomization energy of propyne to -9.05 kcal/mol for the double ionization of Mg. Evaluation of the ɛCV-DFT(ρc, ρv) functional requires less time than a single SCF iteration, and the accuracy is adequate for any model chemistry based on the CCSD(T) level of theory.
Magnetic, Electric and Optical Properties of Mg-Substituted Ni-Cu-Zn Ferrites
NASA Astrophysics Data System (ADS)
Kabbur, S. M.; Ghodake, U. R.; Kambale, Rahul C.; Sartale, S. D.; Chikhale, L. P.; Suryavanshi, S. S.
2017-10-01
The Ni0.25- x Mg x Cu0.30Zn0.45Fe2O4 ( x = 0.00 mol, 0.05 mol, 0.10 mol, 0.15 mol, 0.20 mol and 0.25 mol) magnetic oxide system was prepared by a sol-gel auto-combustion method using glycine as a fuel. X-ray diffraction study reveals the formation of pure spinel lattice symmetry along with the presence of a small fraction of unreacted Fe2O3 phase as a secondary phase due to incomplete combustion reaction between fuel and oxidizer. The lattice constant ( a) was found to decrease with the increase of Mg2+ content; the average crystallite size ( D) is observed in the range of 26.78-33.14 nm. At room temperature, all the samples show typical magnetic hysteresis loops with the decrease of magnetic moment ( n B) of Ni-Cu-Zn ferrites with the increase of Mg2+ content. The intrinsic vibrational absorption bands for the tetrahedral and octahedral sites of the spinel structure were confirmed by infrared (IR) spectroscopy. The optical parameters such as refractive index ( η), velocity of IR waves ( v) and jump rates ( J 1, J 2, J) were studied and found to be dependent on the variation of the lattice constant. The Curie temperature ( T c) of Ni-Cu-Zn mixed ferrite was found to decrease with Mg2+ addition. The composition x = 0.15 mol.% with a low dielectric loss tangent of 2% seems to have potential for multilayer chip inductor applications at a wide range of frequencies.
NASA Astrophysics Data System (ADS)
Wang, Minjuan; Liu, Hong; Fu, Yuming
Atmospheric carbon dioxide concentration [CO _{2}] will increase in the future and will affect global climate and ecosystem productivity. However, this is not clearly an area that requires further study on the most appropriate [CO _{2}] selection for plant growth and quality in a closed, controlled environment. The aim of this study was to determine the variation of photosynthetic characteristics and antioxidant status under five CO _{2} concentration (400, 800, 1200, 2000 and 3000 umol mol (-1) ) on the leaf of Gynura bicolor DC. Here the results show that net photosynthetic rate(Pn), Chl content, edible biomass(EB), leaf blade width(LBW), root weight(RW), fructose(Fru) and sucrose(Suc) of Gynura bicolor DC increased under elevated [CO _{2}] of 800 umol mol (-1) , 1200 umol mol (-1) and 2000 umol mol (-1) . On the contrary, photosynthesis and biomass production declined significantly at 3000 umol mol (-1) CO _{2}, While Lipid peroxidation (LPO), malondialdehyde (MDA) and hydrogen peroxide (H _{2}O _{2}) achieved the highest levels. Furthermore, the contents of glutathione (GSH), vitamin C (VC), and vitamin E (VE), and total antioxidant capacity (T-AOC), the activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) reached the highest level at 2000 umol mol ({-1) }CO _{2}. Results imply that a significant increase in growth and antioxidant defense system of Gynura bicolor DC occurred under 800-2000 umol mol (-1) of CO _{2} concentration provided a theoretical basis for the application for plants selection in Bioregeneration Life Support System (BLSS) and a closed controlled environment.
NASA Astrophysics Data System (ADS)
Yamamoto, Hideki; Sumoge, Iwao
2011-03-01
This study presents the distillation separation of hydrofluoric acid with use of the salt effect on the vapor-liquid equilibrium for acid aqueous solutions and acid mixtures. The vapor-liquid equilibrium of hydrofluoric acid + salt systems (fluorite, potassium nitrate, cesium nitrate) was measured using an apparatus made of perfluoro alkylvinylether. Cesium nitrate showed a salting-out effect on the vapor-liquid equilibrium of the hydrofluoric acid-water system. Fluorite and potassium nitrate showed a salting-in effect on the hydrofluoric acid-water system. Separation of hydrofluoric acid from an acid mixture containing nitric acid and hydrofluoric acid was tested by the simple distillation treatment using the salt effect of cesium nitrate (45 mass%). An acid mixture of nitric acid (5.0 mol · dm-3) and hydrofluoric acid (5.0 mol · dm-3) was prepared as a sample solution for distillation tests. The concentration of nitric acid in the first distillate decreased from 5.0 mol · dm-3 to 1.13 mol · dm-3, and the concentration of hydrofluoric acid increased to 5.41 mol · dm-3. This first distillate was further distilled without the addition of salt. The concentrations of hydrofluoric acid and nitric acid in the second distillate were 7.21 mol · dm-3 and 0.46 mol · dm-3, respectively. It was thus found that the salt effect on vapor-liquid equilibrium of acid mixtures was effective for the recycling of acids from acid mixture wastes.
Molecular energetics of cytosine revisited: a joint computational and experimental study.
Gomes, José R B; Ribeiro da Silva, Maria D M C; Freitas, Vera L S; Ribeiro da Silva, Manuel A V
2007-08-02
A static bomb calorimeter has been used to measure the standard molar energy of combustion, in oxygen, at T = 298.15 K, of a commercial sample of cytosine. From this energy, the standard (p degrees = 0.1 MPa) molar enthalpy of formation in the crystalline state was derived as -(221.9 +/- 1.7) kJ.mol(-1). This value confirms one experimental value already published in the literature but differs from another literature value by 13.5 kJ.mol(-1). Using the present standard molar enthalpy of formation in the condensed phase and the enthalpy of sublimation due to Burkinshaw and Mortimer [J. Chem. Soc., Dalton Trans. 1984, 75], (155.0 +/- 3.0) kJ.mol(-1), results in a value for the gas-phase standard molar enthalpy of formation for cytosine of -66.9 kJ.mol(-1). A similar value, -65.1 kJ.mol(-1), has been estimated after G3MP2B3 calculations combined with the reaction of atomization on three different tautomers of cytosine. In agreement with experimental evidence, the hydroxy-amino tautomer is the most stable form of cytosine in the gas phase. The enthalpies of formation of the other two tautomers were also estimated as -60.7 kJ.mol(-1) and -57.2 kJ.mol(-1) for the oxo-amino and oxo-imino tautomers, respectively. The same composite approach was also used to compute other thermochemical data, which is difficult to be measured experimentally, such as C-H, N-H, and O-H bond dissociation enthalpies, gas-phase acidities, and ionization enthalpies.
Structure and stability of the N-hydroxyurea dimer: Post-Hartree-Fock quantum mechanical study
NASA Astrophysics Data System (ADS)
Jabalameli, Ali; Venkatraman, Ramaiyer; Nowek, Andrzej; Sullivan, Richard H.
2000-10-01
The potential energy surface (PES) search of the N-hydroxyurea dimer was searched with second-order Møller-Plesset perturbation theory (MP2) and the 6-31G(d,p) basis set. Eight local minimum energy structures have been found. Four of them have relatively strong (ΔE˜-10 to -13 kcal/mol) intermolecular interactions and the others are moderately strongly interacting species (ΔE˜-3 to -7 kcal/mol). Final estimation of interaction energies was performed using the larger 6-311G(df,pd) and 6-311G(2df,2pd) basis sets. The predicted interaction energies are ΔE=-14.26 kcal/mol and -3.43 kcal/mol for the strongest and the weakest interacting forms of the studied complex, respectively, at the MP2/6-311G(2df,2pd)//MP2/6-31G(d,p) level of theory. The self-consistent field (SCF) interaction energy decomposition indicates the important influence of the deformation term magnitude on ΔE(SCF). The calculated electron correlation contribution to ΔE(MP2) depends on the geometry of the system and varies from -0.5 to -5 kcal/mol. The estimated influence of water on the stability (free energy of hydration) of N-hydroxyurea dimers using the self-consistent isodensity polarized continuum (SCI-PCM) model of solvation varies from ˜-11 kcal/mol to ˜-21 kcal/mol. The forms predicted to be more strongly interacting species in gas phase are less influenced by hydration than the more weakly interacting ones.
NASA Astrophysics Data System (ADS)
Vishnu Chandar, J.; Shanmugan, S.; Mutharasu, D.; Azlan, A. A.
2017-01-01
Biopolymer nanocomposites are gaining interest due to their biodegradable and biocompatible nature, with exceptional properties which are superior to those of pure polymer and that can be used as a replacement for petroleum-based plastics. Pure poly (3-hydroxybutyrate-co-15 mol% 3hydroxyhexanoate) [P(3HB-co-15 mol% 3HHx)] and ZnO nanoparticles (NPs) reinforced P(3HB-co-15 mol% 3HHx) composite films were prepared and their morphological, optical, and thermal analyses were carried out to study the effect of ZnO NPs on P(3HB-co-15 mol% 3HHx) copolymer. From optical analysis, a strong absorbance peak at ˜358 nm with high intensity for 5%ZnO NPs reinforced P(3HB-co-15 mol% 3HHx) composite sample was observed. Nano-sized particles and their increased trend with increased ZnO NPs concentration were confirmed by UV-Vis spectral analysis. In addition to that, ZnO NPs reduced the reflectance behaviour of P(3HB-co-15 mol% 3HHx) copolymer in the UV region. Field emission scanning electron microscopy analysis evidenced that the pore numbers and their size in the composite matrix was decreased with increased ZnO NPs concentration. Improved thermal stability and melting temperature of the copolymer matrix was confirmed by thermogravimetric analysis and differential scanning calorimetry analysis, respectively. ZnO NPs acted as a retarding agent and showed a low degree of crystallinity (X c ) and enthalpy of melting (ΔH M ). From these observations, ZnO NPs reinforced P(3HB-co-15 mol% 3HHx) composites can be integrated with suitable resin and can be used as an LED encapsulant to block UV rays. They can also be used as a UV blocking coating material in the glass, plastic, and textile industries, for NIR shielding and food packaging applications.
Topolska, Justyna; Manecki, Maciej; Bajda, Tomasz; ...
2016-03-19
Here, the solubility of synthetic pyromorphite Pb 5(PO 4) 3Cl was determined in a series of dissolution experiments conducted at 5–65 °C and at pH = 2.0. The equilibrium was established within 4 months. The dissolution of pyromorphite was congruent at all the temperatures, and the measured solubility product log K sp,298 for the dissolution reaction: Pb 5(PO 4) 3Cl ⇌ 5Pb 2+ + 3PO 4 3- + Cl - was determined to be –79.6 ± 0.15. The equilibrium ion activity product of pyromorphite increased with temperature, indicating a positive enthalpy of the dissolution reaction in the temperature range frommore » 5 to 65 °C. The temperature dependence of the log K sp was nonlinear: log K sp = A – B/T + D log(T), where A = 478.77 ± 136.62, B = 29,378 ± 6215, and D = –185.81 ± 46.77. This allowed for calculation of ΔG° r = 454.0 ± 1.7 kJ·mol –1, ΔH° r = 101.8 ± 6.0 J·mol –1·K –1, ΔC° p,r = –1545 ± 388.9 J·mol –1·K –1, and ΔS° r = –1181 ± 382 J·mol –1·K –1 of the dissolution reaction. Using these values and the published standard state quantities for constituent ions, the values of ΔG° f = –3764.3 ± 3.5 kJ·mol –1, ΔH° f = –4108.4 ± 7.9 J·mol –1·K –1, S° f = 622 ± 382 J·mol –1·K –1, and C° pf = 402 ± 398 J·mol –1·K –1 were calculated for synthetic pyromorphite Pb 5(PO 4) 3Cl.« less
Liu, Ai-Lin; Lu, Wen-Qing; Wang, Zeng-Zhen; Chen, Wei-Hong; Lu, Wen-Hong; Yuan, Jing; Nan, Pei-Hong; Sun, Jian-Ya; Zou, Ya-Lin; Zhou, Li-Hong; Zhang, Chi; Wu, Tang-Chun
2006-01-01
To investigate associations among occupational exposure to coke oven emissions (COEs), oxidative stress, cytogenotoxic effects, change in the metabolizing enzyme glutathione S-transferase (GST), and internal levels of polycyclic aromatic hydrocarbons (PAHs) in coke oven workers, we recruited 47 male coke oven workers and 31 male control subjects from a coke oven plant in northern China. We measured the levels of 1-hydroxypyrene (1-OHP) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in urine, micronucleated binucleated cells (BNMNs) in peripheral blood lymphocyte, and GST in serum. Our results showed that the group exposed to COEs had significantly increased levels of 1-OHP [median 5.7; interquartile range (IQR), 1.4–12.0 μmol/mol creatinine] compared with the control group (3; 0.5–6.4 μmol/mol creatinine). In addition, the median levels (IQR) of 8-OHdG, BNMNs, and GST were markedly increased in the exposed [1.9 (1.4–15.4) μmol/mol creatinine; 6 (2–8) per thousand; 22.1 (14.9–31.2) U/L, respectively] compared with controls [1.3 (1.0–4.0) μmol/mol creatinine, 2 (0–4) per thousand; and 13.1 (9.5–16.7) U/L, respectively]. These results appeared to be modified by smoking. However, multivariate logistic regression analysis revealed that exposure to COEs had the highest odds ratio among variables analyzed and that smoking was not a significant confounder of the levels of studied biomarkers. Overall, the present findings suggest that COE exposure led to increased internal PAH burden, genetic damage, oxidative stress, and GST activity. The consequences of the changes in these biomarkers, such as risk of cancer, warrant further investigations. PMID:16675419
Alecu, I M; Gao, Yide; Hsieh, P-C; Sand, Jordan P; Ors, Ahmet; McLeod, A; Marshall, Paul
2007-05-17
The laser flash photolysis resonance fluorescence technique was used to monitor atomic Cl kinetics. Loss of Cl following photolysis of CCl4 and NaCl was used to determine k(Cl + C6H6) = 6.4 x 10(-12) exp(-18.1 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 578-922 K and k(Cl + C6D6) = 6.2 x 10(-12) exp(-22.8 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 635-922 K. Inclusion of literature data at room temperature leads to a recommendation of k(Cl + C6H6) = 6.1 x 10(-11) exp(-31.6 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) for 296-922 K. Monitoring growth of Cl during the reaction of phenyl with HCl led to k(C6H5 + HCl) = 1.14 x 10(-12) exp(+5.2 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 294-748 K, k(C6H5 + DCl) = 7.7 x 10(-13) exp(+4.9 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 292-546 K, an approximate k(C6H5 + C6H5I) = 2 x 10(-11) cm(3) molecule(-1) s(-1) over 300-750 K, and an upper limit k(Cl + C6H5I) < or = 5.3 x 10(-12) exp(+2.8 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 300-750 K. Confidence limits are discussed in the text. Third-law analysis of the equilibrium constant yields the bond dissociation enthalpy D(298)(C6H5-H) = 472.1 +/- 2.5 kJ mol(-1) and thus the enthalpy of formation Delta(f)H(298)(C6H5) = 337.0 +/- 2.5 kJ mol(-1).
Predictors of adverse neonatal outcomes in intrahepatic cholestasis of pregnancy.
Kawakita, Tetsuya; Parikh, Laura I; Ramsey, Patrick S; Huang, Chun-Chih; Zeymo, Alexander; Fernandez, Miguel; Smith, Samuel; Iqbal, Sara N
2015-10-01
We sought to determine predictors of adverse neonatal outcomes in women with intrahepatic cholestasis of pregnancy (ICP). This study was a multicenter retrospective cohort study of all women diagnosed with ICP across 5 hospital facilities from January 2009 through December 2014. Obstetric and neonatal complications were evaluated according to total bile acid (TBA) level. Multivariable logistic regression models were developed to evaluate predictors of composite neonatal outcome (neonatal intensive care unit admission, hypoglycemia, hyperbilirubinemia, respiratory distress syndrome, transient tachypnea of the newborn, mechanical ventilation use, oxygen by nasal cannula, pneumonia, and stillbirth). Predictors including TBA level, hepatic transaminase level, gestational age at diagnosis, underlying liver disease, and use of ursodeoxycholic acid were evaluated. Of 233 women with ICP, 152 women had TBA levels 10-39.9 μmol/L, 55 had TBA 40-99.9 μmol/L, and 26 had TBA ≥100 μmol/L. There was no difference in maternal age, ethnicity, or prepregnancy body mass index according to TBA level. Increasing TBA level was associated with higher hepatic transaminase and total bilirubin level (P < .05). TBA levels ≥100 μmol/L were associated with increased risk of stillbirth (P < .01). Increasing TBA level was also associated with earlier gestational age at diagnosis (P < .01) and ursodeoxycholic acid use (P = .02). After adjusting for confounders, no predictors were associated with composite neonatal morbidity. TBA 40-99.9 μmol/L and TBA ≥100 μmol/L were associated with increased risk of meconium-stained amniotic fluid (adjusted odds ratio, 3.55; 95% confidence interval, 1.45-8.68 and adjusted odds ratio, 4.55; 95% confidence interval, 1.47-14.08, respectively). In women with ICP, TBA level ≥100 μmol/L was associated with increased risk of stillbirth. TBA ≥40 μmol/L was associated with increased risk of meconium-stained amniotic fluid. Copyright © 2015 Elsevier Inc. All rights reserved.
Elevated phenylalanine on newborn screening: follow-up testing may reveal undiagnosed galactosaemia.
Shakespeare, Lynette; Downing, Melanie; Allen, Joyce; Casbolt, Ann-Marie; Ellin, Sheila; Maloney, Martin; Race, Gillian; Bonham, Jim
2010-11-01
Introduction Newborn screening for phenylketonuria (PKU) can reveal other conditions which lead to an increased blood spot phenylalanine (Phe) concentration. We have investigated the proportion of blood spot samples that gave a positive screen due to clinically significant conditions other than PKU, compared the positive predictive value (PPV) of our referral Phe cut-off with that recommended by the UK Newborn Screening Programme Centre (UKNSPC) (>210 and >240 μmol/L, respectively) and evaluated the effectiveness of reflex testing for galactosaemia using a lower blood spot Phe cut-off concentration of 130 μmol/L. All blood spot samples that screened positive, for an increased Phe concentration, between April 2001 and March 2008, were identified from the records of the Sheffield Newborn Screening Laboratory and the diagnoses noted. In addition, all cases of galactosaemia detected in or notified to our screening laboratory within this time were also examined and the screened Phe concentrations compared. Out of 438,674 babies who were screened, 67 had Phe concentration >210 μmol/L (15 per 100,000). Of these, 40 had PKU or persistent hyperphenylalaninaemia with a Phe concentration identified by screening between 270 and 2350 μmol/L. A further 11 were diagnosed with another clinically significant disorder: galactosaemia (n = 8), biopterin defects (n = 2), tyrosinaemia Type 1 (n = 1). In addition, 16 had transient elevations in Phe. In total, nine cases of galactosaemia were identified, of whom, three had Phe concentrations <240 μmol/L with one asymptomatic individual having a concentration <210 μmol/L. Adoption of the UKNSPC recommended cut-off (>240 μmol/L) will not affect the detection rate of classical PKU, but will improve the PPV from 76% to 80%. The use of a lower cut-off (130 μmol/L) for reflex galactosaemia testing enables the timely identification of asymptomatic cases that benefit particularly from early treatment, without prompting any unnecessary clinical referrals or delaying any referrals. This intervention may reduce mortality in this vulnerable group.
Thermodynamic characterization of three polymorphic forms of piracetam.
Picciochi, Ricardo; Diogo, Hermínio P; da Piedade, Manuel E Minas
2011-02-01
Combustion calorimetry, solution calorimetry, and differential scanning calorimetry (DSC) were used to determine the standard (p° = 0.1 MPa) molar enthalpies of formation of Forms I, II, and III piracetam at 298.15 K, namely, Δ(f) H(m)° (C(6)H(10)O(2)N(2), cr I) = -520.6 ± 1.6 kJ·mol(-1), Δ(f) H(m)° (C(6)H(10)O(2)N(2), cr II) = -523.8 ± 1.6 kJ·mol(-1), and Δ(f) H(m)° (C(6)H(10)O(2)N(2), cr III) = -524.1 ± 1.6 kJ·mol(-1). The enthalpy of formation of gaseous piracetam at 298.15 K was also derived as Δ(f) H(m)° (C(6)H(10)O(2)N(2), g) = -401.3 ± 2.1 kJ·mol(-1), by combining the standard molar enthalpy of formation of Form II piracetam with the corresponding enthalpy of sublimation, Δ(sub) H(m)° (C(6) H(10) O(2) N(2), cr II) = 122.5 ± 1.4 kJ·mol(-1), obtained by drop-sublimation Calvet microcalorimetry and the Knudsen effusion method. The Δ(f) H(m)° (C(6)H(10)O(2)N(2), g) value was used to assess the corresponding predictions by the B3LYP/cc-pVTZ (-335.3 kJ·mol(-1)), G3MP2 (-388.7 kJ·mol(-1)), and CBS-QB3 (-402.8 kJ·mol(-1)) methods, based on the calculation of the atomization enthalpy of piracetam. Finally, the results of the solution and DSC experiments indicate that the stability hierarchy of Forms I, II, and III piracetam at 298.15 K, for which there was conflicting evidence in the literature, is III > II > I. Copyright © 2010 Wiley-Liss, Inc.
Anthropogenic CO2 emissions from a megacity in the Yangtze River Delta of China.
Hu, Cheng; Liu, Shoudong; Wang, Yongwei; Zhang, Mi; Xiao, Wei; Wang, Wei; Xu, Jiaping
2018-06-03
Anthropogenic CO 2 emissions from cities represent a major source contributing to the global atmospheric CO 2 burden. Here, we examined the enhancement of atmospheric CO 2 mixing ratios by anthropogenic emissions within the Yangtze River Delta (YRD), China, one of the world's most densely populated regions (population greater than 150 million). Tower measurements of CO 2 mixing ratios were conducted from March 2013 to August 2015 and were combined with numerical source footprint modeling to help constrain the anthropogenic CO 2 emissions. We simulated the CO 2 enhancements (i.e., fluctuations superimposed on background values) for winter season (December, January, and February). Overall, we observed mean diurnal variation of CO 2 enhancement of 23.5~49.7 μmol mol -1 , 21.4~52.4 μmol mol -1 , 28.1~55.4 μmol mol -1 , and 29.5~42.4 μmol mol -1 in spring, summer, autumn, and winter, respectively. These enhancements were much larger than previously reported values for other countries. The diurnal CO 2 enhancements reported here showed strong similarity for all 3 years of the study. Results from source footprint modeling indicated that our tower observations adequately represent emissions from the broader YRD area. Here, the east of Anhui and the west of Jiangsu province contributed significantly more to the anthropogenic CO 2 enhancement compared to the other sectors of YRD. The average anthropogenic CO 2 emission in 2014 was 0.162 (± 0.005) mg m -2 s -1 and was 7 ± 3% higher than 2010 for the YRD. Overall, our emission estimates were significantly smaller (9.5%) than those estimated (0.179 mg m -2 s -1 ) from the EDGAR emission database.
López-Canales, Jorge Skiold; Lozano-Cuenca, Jair; López-Canales, Oscar Alberto; Aguilar-Carrasco, José Carlos; Aranda-Zepeda, Lidia; López-Sánchez, Pedro; Castillo-Henkel, Enrique Fernando; López-Mayorga, Ruth Mery; Valencia-Hernández, Ignacio
2015-01-01
The present study aimed to investigate the possible influence of several inhibitors and blockers on the vascular effect produced by the acute in vitro application of rosuvastatin to phenylephrine-precontracted aortic rings from rats with a semi-solid, cafeteria-style (CAF) diet. It also aimed to examine the effects of rosuvastatin on the expression of endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase, constitutive cyclooxygenase, and inducible cyclooxygenase in aortic rings from rats with a CAF diet. From comparisons of the effect on phenylephrine-precontracted aortic rings extracted from rats with two different diets (a standard and a CAF diet), it was found that 10−9–10−5-mol/L rosuvastatin produced lower concentration-dependent vasorelaxation on rings from the CAF diet group. The vasorelaxant effect was unaffected by the vehicle, but it was significantly attenuated by 10−5-mol/L NG-nitro-l-arginine methyl ester, 10−2-mol/L tetraethylammonium, 10−3-mol/L 4-aminopyridine, 10−7-mol/L apamin plus 10−7-mol/L charybdotoxin, 10−5-mol/L indomethacin, or 10−5-mol/L cycloheximide. Moreover, in aortic rings from rats with a CAF diet, rosuvastatin enhanced the expression of eNOS, inducible nitric oxide synthase, constitutive cyclooxygenase, and inducible cyclooxygenase. The acute in vitro application of rosuvastatin to phenylephrine-precontracted aortic rings from rats with a CAF diet had a vasorelaxant effect. Overall, the present results suggest that the stimulation of eNOS, the opening of Ca2+-activated and voltage-activated K+ channels, the stimulation of prostaglandin synthesis and enhanced protein levels of eNOS, inducible nitric oxide synthase, constitutive cyclooxygenase, and inducible cyclooxygenase are involved in this relaxant effect. PMID:25881486
In-vitro study of methylglyoxal and aspirin effects on fibrinolysis parameters.
Pouya, Fahima D; Zavar-Reza, Javad; Jalali, Beman A
2013-10-01
Methylglyoxal is a reactive α, β dicarbonyl aldehyde compound that originates from various biochemical pathways. Some studies suggest that increased methylglyoxal in blood leads to changes in fibrinolysis; however, the precise mechanism is not clear. The aim of this study was to compare different concentrations of methylglyoxal and aspirin on fibrinolysis in the plasma of healthy individuals in vitro. Different concentrations of methylglyoxal (5, 50, 100, and 500 μmol/l) and aspirin (1, 10, and 100 mg/l) were added to the plasma citrate. They were incubated at 37°C for 24 h. Then, fibrinolysis parameters were analyzed by the turbidimetric procedure at 405 nm. The Independent Samples t-test was utilized to compare them (P < 0.05). Findings revealed that methylglyoxal at 500 μmol/l with aspirin 100 mg/l had significant changes in the maximum lysis velocity (0.163 ± 0.003), half-time lysis (240 ± 10.00), the total lysis time (485 ± 5.00), lag time in lysis (126 ± 5.77), compared with methylglyoxal at 500 μmol/l (0.104 ± 0.005), (276 ± 5.77), (570 ± 10.00), and (186 ± 5.77), respectively (P < 0.05). Methylglyoxal at 500 μmol/l with aspirin 1 mg/l did not significantly change in either parameter (P > 0.05). Methylglyoxal at 100 μmol/l with aspirin 1 mg/l did not significantly change in either fibrinolysis parameter (P > 0.05), compared with methylglyoxal at 100 μmol/l. Methylglyoxal at 5 μmol/l with aspirin (1, 10, 100 mg/l) changed in all fibrinolysis parameters (P < 0.05), compared with methylglyoxal at 5 μmol/l. The other concentrations were compared in the same way. Aspirin (more than 1 mg/l) had more effect on higher concentrations of methylglyoxal. It increased the velocity of lysis of the clot and shortened clot lysis.
Thermochemical properties for isooctane and carbon radicals: computational study.
Snitsiriwat, Suarwee; Bozzelli, Joseph W
2013-01-17
Thermochemical properties for isooctane, its internal rotation conformers, and radicals with corresponding bond energies are determined by use of computational chemistry. Enthalpies of formation are determined using isodesmic reactions with B3LYP density function theory and composite CBS-QB3 methods. Application of group additivity with comparison to calculated values is illustrated. Entropy and heat capacities are determined using geometric parameters, internal rotor potentials, and frequencies from B3LYP/6-31G(d,p) calculations for the lowest energy conformer. Internal rotor potentials are determined for the isooctane parent and for the primary, secondary, and tertiary radicals in order to identify isomer energies. Intramolecular interactions are shown to have a significant effect on the enthalpy of formation of the isooctane parent and its radicals. The computed standard enthalpy of formation for the lowest energy conformers of isooctane from this study is -54.40 ± 1.60 kcal mol(-1), which is 0.8 kcal mol(-1) lower than the evaluated experimental value -53.54 ± 0.36 kcal mol(-1). The standard enthalpy of formation for the primary radical for a methyl on the quaternary carbon is -5.00 ± 1.69 kcal mol(-1), for the primary radical on the tertiary carbon is -5.18 ± 1.69 kcal mol(-1), for the secondary isooctane radical is -9.03 ± 1.84 kcal mol(-1), and for the tertiary isooctane radical is -12.30 ± 2.02 kcal mol(-1). Bond energy values for the isooctane radicals are 100.64 ± 1.73, 100.46 ± 1.73, 96.41 ± 1.88 and 93.14 ± 2.05 kcal mol(-1) for C3•CCCC2, C3CCCC2•, C3CC•CC2, and C3CCC•C2, respectively. Entropy and heat capacity values are reported for the lowest energy homologues.
[Effect of aspirin on cell biological activities in murine bone marrow stromal cells].
Du, Mi; Pan, Wan; Yang, Pishan; Ge, Shaohua
2016-03-01
To determine the effect of aspirin on cell proliferation, alkaline phosphatase (ALP) activity, cell cycle and apoptosis in murine bone marrow stromal cells, so as to explore an appropriate dose range to improve bone regeneration in periodontal treatment. ST2 cells were stimulated with aspirin (concentrations of 1, 10, 100 and 1 000 μmol/L) for 1, 2, 3, 5 and 7 d. Cell proliferation was measured by methyl thiazolyl tetrazolium (MTT) assay. After ST2 cells were treated for 1, 3 and 7 d, ALP activity was measured by ALP kit, cell cycle and apoptosis were measured by flow cytometry (FCM) after treated for 48 h. MTT assays showed that various doses of aspirin have different effects on the cell growth. Briefly, lower concentrations (1, 10 μmol/L) of aspirin promoted the cell growth, the A value of 0, 1 and 10 μmol/L aspirin 7-day-treated cells were 0.313±0.012, 0.413±0.010 and 0.387±0.017 respectively (P <0.01 vs control), and so did the ALP level ([4.3±0.9], [6.0±0.3] and [7.7±0.4] μmol·min(-1)·g(-1), P <0.05 vs control), while higher concentrations, especially 1000 μmol/L of aspirin might inhibit the cell growth with time going, A value and ALP level were 0.267±0.016, (4.3±1.3) μmol·min(-1)·g(-1) respectively (P <0.05 vs control). Cell cycle analysis revealed no changes in comparison to control cells after treatment with 1 or 10 μmol/L aspirin, but it was observed that cell mitosis from S phase to G2/M phase proceeded at higher concentrations of 100 μmol/L aspirin, and the cell cycle in phase G0/G1 arrested at 1000 μmol/L. Parallel apoptosis/necrosis studies showed that the percentage of cells in apoptosis decreased dramatically at all doses of aspirin, the apoptosis rates of ST2 cells responded to 0, 1, 10, 100 and 1000 μmol/L aspirin were (11.50±0.90)%, (5.30±0.10)%, (5.50±0.10)%, (4.90±0.90)% and (7.95±0.25)% respectively (P<0.05 vs control). This study demonstrated that lower dosage of aspirin can promote ST2 cells growth, osteogenic activity and inhibit its apoptosis. Aspirin maybe used for the bone reconstruction with a proper concentration.
Asou, H; Koike, M; Elstner, E; Cambell, M; Le, J; Uskokovic, M R; Kamada, N; Koeffler, H P
1998-10-01
We have studied the in vitro biological activities and mechanisms of action of 1,25-dihydroxyvitamin D3 (1,25D3) and nine potent 1,25D3 analogs on proliferation and differentiation of myeloid leukemia cell lines (HL-60, retinoic acid-resistant HL-60 [RA-res HL-60], NB4 and Kasumi-1). The common novel structural motiff for almost all the analogs included removal of C-19 (19-nor); each also had unsaturation of the side chain. All the compounds were potent; for example, the concentration of analogs producing a 50% clonal inhibition (ED50) ranged between 1 x 10(-9) to 4 x 10(-11) mol/L when using the HL-60 cell line. The most active compound [1, 25(OH)2-16,23E-diene-26-trifluoro-19-nor-cholecalciferol (Ro 25-9716)] had an ED50 of 4 x 10(-11) mol/L; in contrast, the 1,25D3 produced an ED50 of 10(-9) mol/L with the HL-60 target cells. Ro 25-9716 (10(-9) mol/L, 3 days) was a strong inducer of myeloid differentiation because it caused 92% of the HL-60 cells to express CD11b and 75% of these cells to reduce nitroblue tetrazolium (NBT). This compound (10(-8) mol/L, 4 days) also caused HL-60 cells to arrest in the G1 phase of the cell cycle (88% cells in G1 v 48% of the untreated control cells). The p27(kip-1), a cyclin-dependent kinase inhibitor which is important in blocking the cell cycle, was induced more quickly and potently by Ro 25-9716 (10(-7) mol/L, 0 to 5 days) than by 1,25D3, suggesting a possible mechanism by which these analogs inhibit proliferation of leukemic growth. The NB4 promyelocytic leukemia cells cultured with the Ro 25-9716 were also inhibited in their clonal proliferation (ED50, 5 x 10(-11) mol/L) and their expression of CD11b was enhanced (80% positive [10(-9) mol/L, 4 days] v 27% untreated NB4 cells). Moreover, the combination of Ro 25-9716 (10(-9) mol/L) and all-trans retinoic acid (ATRA, 10(-7) mol/L) induced 92% of the NB4 cells to reduce NBT, whereas only 26% of the cells became NBT positive after a similar exposure to the combination of 1,25D3 and ATRA. Surprisingly, Ro 25-9716 also inhibited the clonal growth of poorly differentiated leukemia cell lines (RA-res HL-60 [ED50, 4 x 10(-9) mol/L] and Kasumi-1 [ED50, 5 x 10(-10) mol/L]). For HL-60 cells, Ro 25-9716 markedly decreased the percent of the cells in S phase of the cell cycle and increased the expression of the cyclin-dependent kinase inhibitor, p27(kip-1). In summary, 19-nor vitamin D3 compounds strongly induced differentiation and inhibited clonal proliferation of various myeloid leukemia cell lines, suggesting a therapeutic niche for their use in myeloid leukemia.
2007-06-01
AF317741) 93 EPR3970- MOlA -Bc32 gamma-Proteobacteria Uncultured gamma proteobacterium clone AT-s80 (AY225635) 99 FPR3970-MO IA-Bc33 Actinobacteria...bacterium partial I AJ966584) 99 1iPR3970- MOlA -Bc65 Unidentified Uncultured bacterium clone CV90 (DQ499320) 89 1iPR3970- MOlA -Bc66 Unidentified Uncultured
1-[1-(4-Chlorophenyl)ethylidene]carbonohydrazide
Du, Lingyun; Du, Lei; Wang, Shuhao
2009-01-01
The molecular skeleton of the title molecule, C9H11ClN4O, is essentially planar, the dihedral angle between the ring and the and N/N/C plane being 6.7 (3)°. In the crystal, intermolecular N—H⋯O and N—H⋯N hydrogen bonds link the molecules into ribbons propagated along [010]. PMID:21577542
Ema, Tadashi; Nanjo, Yoshiko; Shiratori, Sho; Terao, Yuta; Kimura, Ryo
2016-11-04
The intermolecular or intramolecular asymmetric benzoin reaction was catalyzed by a small amount of N-heterocyclic carbene (NHC) (0.2-1 mol %) under solvent-free conditions. The solvent-free intramolecular asymmetric Stetter reaction also proceeded efficiently with NHC (0.2-1 mol %). In some cases, even solid-to-solid or solid-to-liquid conversions took place with low catalyst loading (0.2-1 mol %).
2015-11-19
hand, the energy change for CO3 2- +O2→CO5 2- is calculated to be - 105.5 kJ/mol and -87.3 kJ/mol by B3LYP and CCSD(T), respectively. Similarly, the...formation energy of CO4 2- ( CO3 2- +1/2O2→CO4 2- ) is -9.8 kJ/mol and -5.4 kJ/mol by B3LYP and CCSD(T), respectively. All testing results have...This configuration is same as those in their crystal structures of bulk Li2CO3, Na2CO3, and K2CO3. In addition, the average bond length between alkali
Oxidation of 1,3,7-trimethylxanthine by hypochlorite ion
NASA Astrophysics Data System (ADS)
Kheidorov, V. P.; Ershov, Yu. A.; Chalyi, G. Yu.; Titorovich, O. V.
2011-08-01
The kinetics of the oxidative conversion of 1,3,7-trimethylxanthine upon treatment with hypochlorite ions (OCl-) in aqueous medium at 283-298 K and pH 8.2 was studied. The reaction order with respect to each component was determined and proved to be 1. It was established that the temperature dependence of the reaction rate follows the Arrhenius equation. The activation parameters of the reaction were measured: E a = 33.58 kJ/mol, Δ H ≠ = 31.12 kJ/mol, Δ S ≠ = -170.02 J/(K mol), Δ G ≠ = 81.45 kJ/mol. The stoichiometry of the reaction was studied, and the chemistry of the oxidative conversion of caffeine treated with OCl- is discussed.
1,1′:4′,1′′-Terphenyl-2′,5′-dicarboxylic acid dimethyl sulfoxide-d 6 disolvate
Pop, Lucian C.; Preite, Marcelo; Manriquez, Juan Manuel; Vega, Andrés; Chavez, Ivonne
2012-01-01
The asymmetric unit of the title solvate, C20H14O4·2C2D6OS, contains half of the substituted terephthalic acid molecule and one solvent molecule. The centroid of the central benzene ring in the acid molecule is coincident with a crystallographic inversion center. Neither the carboxyl nor the phenyl substituents are coplanar with the central aromatic ring, showing dihedral angles of 53.18 (11) and 47.83 (11)°, respectively. The dimethyl sulfoxide solvent molecules are hydrogen bonded to the carboxylic acid groups. PMID:22606132
Gas standards development in support of NASA's sensor calibration program around the space shuttle.
Rhoderick, George C; Thorn, William J; Miller, Walter R; Guenther, Franklin R; Gore, Eric J; Fish, Timothy O
2009-05-15
The National Aeronautics and Space Administration (NASA) Kennedy Space Center (KSC) requires accurate gas mixtures containing argon (Ar), helium (He), hydrogen (H(2)), and oxygen (O(2)) in a balance of nitrogen (N(2)) to calibrate mass spectrometer-based sensors used around their manned and unmanned space vehicles. This also includes space shuttle monitoring around the launch area and inside the shuttle cabin. NASA was in need of these gas mixtures to ensure the safety of the shuttle cabin and the launch system. In 1993, the National Institute of Standards and Technology (NIST) was contracted by NASA to develop a suite of primary standard mixtures (PSMs) containing helium, hydrogen, argon, and oxygen in a balance gas of nitrogen. NIST proceeded to develop a suite of 20 new gravimetric primary PSMs. At the same time NIST contracted Scott Specialty Gases (Plumsteadville, PA) to prepare 18 cylinder gas mixtures which were then sent to NIST. NIST used their newly prepared PSMs to assign concentration values ranging from 100 to 10,000 micromol/mol with relative expanded uncertainties (95% confidence interval) of 0.8-10% to the 18 Scott Specialty Gases prepared mixtures. A total of 12 of the mixtures were sent to NASA as NIST traceable standards for calibration of their mass spectrometers. The remaining 6 AIRGAS mixtures were retained at NIST. In 2006, these original 12 gas standards at NASA had become low in pressure and additionally NASA needed a lower concentration level; therefore, NIST was contracted to certify three new sets of gas standards. NIST prepared a new suite of 22 PSMs with weighing uncertainties of <0.1%. These 22 PSMs were compared to some of the original 20 PSMs developed in 1993 and with the NIST valued assigned Scott Specialty Gas mixtures that NIST had retained. Results between the two suites of primary standards and the 1993 NASA mixtures agreed, verifying their stability. At the same time, NASA contracted AIRGAS (Chicago, Illinois) to prepare 45 cylinder gas mixtures which were then sent to NIST. Each of the 3 sets of standards contained 15 cylinder gas mixtures: set no. 1, He at 12,000 micromol/mol, H(2) at 600 micromol/mol, Ar at 100 micromol/mol, and O(2) at 600 micromol/mol; set no. 2, He at 15 000 micromol/mol, H(2) at 5000 micromol/mol, Ar at 1000 micromol/mol, O(2) at 5000 micromol/mol; and set no. 3, He at 50 micromol/mol, H(2), Ar, and O(2) each at 25 micromol/mol with a balance gas of N(2). NIST used their newly prepared primary standards to assign concentration values to each component in these three new mixture sets to relative expanded uncertainties of 0.5-2.2%. The NIST certified AIRGAS prepared mixtures were then sent to NASA to use as "working standards" to calibrate their mass spectrometers (MSs).
Banach, Maciej; Serban, Corina; Ursoniu, Sorin; Rysz, Jacek; Muntner, Paul; Toth, Peter P; Jones, Steven R; Rizzo, Manfredi; Glasser, Stephen P; Watts, Gerald F; Blumenthal, Roger S; Lip, Gregory Y H; Mikhailidis, Dimitri P; Sahebkar, Amirhossein
2015-09-01
Statin therapy may lower plasma coenzyme Q10 (CoQ10) concentrations, but the evidence as to the significance of this effect is unclear. We assessed the impact of statin therapy on plasma CoQ10 concentrations through the meta-analysis of available RCTs. The literature search included selected databases up to April 30, 2015. The meta-analysis was performed using either a fixed-effects or random-effect model according to I(2) statistic. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence interval (CI). The data from 8 placebo-controlled treatment arms suggested a significant reduction in plasma CoQ10 concentrations following treatment with statins (WMD: -0.44 μmol/L, 95%CI: -0.52, -0.37, p<0.001). The pooled effect size was robust and remained significant in the leave-one-out sensitivity analysis. Subgroup analysis suggested that the impact of statins on plasma CoQ10 concentrations is significant for all 4 types of statins studied i.e. atorvastatin (WMD: -0.41 μmol/L, 95%CI: -0.53, -0.29, p<0.001), simvastatin (WMD: -0.47 μmol/L, 95% CI: -0.61, -0.33, p<0.001), rosuvastatin (WMD: -0.49 μmol/L, 95%CI: -0.67, -0.31, p<0.001) and pravastatin (WMD: -0.43 μmol/L, 95%CI: -0.69, -0.16, p=0.001). Likewise, there was no differential effect of lipophilic (WMD: -0.43 μmol/L, 95%CI: -0.53, -0.34, p<0.001) and hydrophilic statins (WMD: -0.47 μmol/L, 95%CI: -0.62, -0.32, p<0.001). With respect to treatment duration, a significant effect was observed in both subsets of trials lasting <12 weeks (WMD: -0.51 μmol/L, 95%CI: -0.64, -0.39, p<0.001) and ≥12 weeks (WMD: -0.40 μmol/L, 95%CI: -0.50, -0.30, p<0.001). The meta-analysis showed a significant reduction in plasma CoQ10 concentrations following treatment with statins. Further well-designed trials are required to confirm our findings and elucidate their clinical relevance. Copyright © 2015 Elsevier Ltd. All rights reserved.
Mechanism and kinetics for ammonium dinitramide (ADN) sublimation: a first-principles study.
Zhu, R S; Chen, Hui-Lung; Lin, M C
2012-11-08
The mechanism for sublimation of NH(4)N(NO(2))(2) (ADN) has been investigated quantum-mechanically with generalized gradient approximation plane-wave density functional theory calculations; the solid surface is represented by a slab model and the periodic boundary conditions are applied. The calculated lattice constants for the bulk ADN, which were found to consist of NH(4)(+)[ON(O)NNO(2)](-) units, instead of NH(4)(+)[N(NO(2))(2)](-), agree quite well with experimental values. Results show that three steps are involved in the sublimation/decomposition of ADN. The first step is the relaxation of the surface layer with 1.6 kcal/mol energy per NH(4)ON(O)NNO(2) unit; the second step is the sublimation of the surface layer to form a molecular [NH(3)]-[HON(O)NNO(2)] complex with a 29.4 kcal/mol sublimation energy, consistent with the experimental observation of Korobeinichev et al. (10) The last step is the dissociation of the [H(3)N]-[HON(O)NNO(2)] complex to give NH(3) and HON(O)NNO(2) with the dissociation energy of 13.9 kcal/mol. Direct formation of NO(2) (g) from solid ADN costs a much higher energy, 58.3 kcal/mol. Our calculated total sublimation enthalpy for ADN(s) → NH(3)(g) + HON(O)NNO(2)) (g), 44.9 kcal/mol via three steps, is in good agreement with the value, 42.1 kcal/mol predicted for the one-step sublimation process in this work and the value 44.0 kcal/mol computed by Politzer et al. (11) using experimental thermochemical data. The sublimation rate constant for the rate-controlling step 2 can be represented as k(sub) = 2.18 × 10(12) exp (-30.5 kcal/mol/RT) s(-1), which agrees well with available experimental data within the temperature range studied. The high pressure limit decomposition rate constant for the molecular complex H(3)N···HON(O)NNO(2) can be expressed by k(dec) = 3.18 × 10(13) exp (-15.09 kcal/mol/RT) s(-1). In addition, water molecules were found to increase the sublimation enthalpy of ADN, contrary to that found in the ammonium perchlorate system, in which water molecules were shown to reduce pronouncedly the enthalpy of sublimation.
Jin, Ying; Sui, Hai-juan; Dong, Yan; Ding, Qi; Qu, Wen-hui; Yu, Sheng-xue; Jin, Ying-xin
2012-01-01
Aim: To investigate whether atorvastatin can promote formation of neurites in cultured cortical neurons and the signaling mechanisms responsible for this effect. Methods: Cultured rat cerebral cortical neurons were incubated with atorvastatin (0.05–10 μmol/L) for various lengths of time. For pharmacological experiments, inhibitors were added 30 min prior to addition of atorvastatin. Control cultures received a similar amount of DMSO. Following the treatment period, phase-contrast digital images were taken. Digital images of neurons were analyzed for total neurite branch length (TNBL), neurite number, terminal branch number, and soma area by SPOT Advanced Imaging software. After incubation with atorvastatin for 48 h, the levels of phosphorylated 3-phosphoinoside-dependent protein kinase-1 (PDK1), phospho-Akt, phosphorylated mammalian target of rapamycin (mTOR), phosphorylated 4E-binding protein 1 (4E-BP1), p70S6 kinase (p70S6K), and glycogen synthase kinase-3β (GSK-3β) in the cortical neurons were evaluated using Western blotting analyses. Results: Atorvastatin (0.05–10 μmol/L) resulted in dose-dependent increase in neurite number and length in these neurons. Pretreatment of the cortical neurons with phosphatidylinositol 3-kinase (PI3K) inhibitors LY294002 (30 μmol/L) and wortmannin (5 μmol/L), Akt inhibitor tricribine (1 μmol/L) or mTOR inhibitor rapamycin (100 nmol/L) blocked the atorvastatin-induced increase in neurite outgrowth, suggesting that atorvastatin promoted neurite outgrowth via activating the PI3K/Akt/mTOR signaling pathway. Atorvastatin (10 μmol/L) significantly increased the levels of phosphorylated PDK1, Akt and mTOR in the cortical neurons, which were prevented by LY294002 (30 μmol/L). Moreover, atorvastatin (10 μmol/L) stimulated the phosphorylation of 4E-BP1 and p70S6K, the substrates of mTOR, in the cortical neurons. In addition, atorvastatin (10 μmol/L) significantly increased the phosphorylated GSK-3β level in the cortical neurons, which was prevented by both LY294002 and tricribine. Conclusion: These results suggest that activation of both the PI3K/Akt/mTOR and Akt/GSK-3β signaling pathways is responsible for the atorvastatin-induced neurite outgrowth in cultured cortical neurons. PMID:22705730
Trapping-mediated dissociative chemisorption of C3H8 and C3D8 on Ir(110)
NASA Astrophysics Data System (ADS)
Kelly, D.; Weinberg, W. H.
1996-07-01
We have employed molecular beam techniques to investigate the molecular trapping and trapping-mediated dissociative chemisorption of C3H8 and C3D8 on Ir(110) at low beam translational energies, Ei≤5 kcal/mol, and surface temperatures, Ts, from 85 to 1200 K. For Ts=85 K, C3H8 is molecularly adsorbed on Ir(110) with a trapping probability, ξ, equal to 0.94 at Ei=1.6 kcal/mol and ξ=0.86 at Ei=5 kcal/mol. At Ei=1.9 kcal/mol and Ts=85 K, ξ of C3D8 is equal to 0.93. From 150 K to approximately 700 K, the initial probabilities of dissociative chemisorption of propane decrease with increasing Ts. For Ts from 700 to 1200 K, however, the initial probability of dissociative chemisorption maintains the essentially constant value of 0.16. These observations are explained within the context of a kinetic model which includes both C-H (C-D) and C-C bond cleavage. Below 450 K propane chemisorption on Ir(110) arises essentially solely from C-H (C-D) bond cleavage, an unactivated mechanism (with respect to a gas-phase energy zero) for this system, which accounts for the decrease in initial probabilities of chemisorption with increasing Ts. With increasing Ts, however, C-C bond cleavage, the activation energy of which is greater than the desorption energy of physically adsorbed propane, increasingly contributes to the measured probability of dissociative chemisorption. The activation energies, referenced to the bottom of the physically adsorbed molecular well, for C-H and C-C bond cleavage for C3H8 on Ir(110) are found to be Er,CH=5.3±0.3 kcal/mol and Er,CC=9.9±0.6 kcal/mol, respectively. The activation energies for C-D and C-C bond cleavage for C3D8 on Ir(110) are 6.3±0.3 kcal/mol and 10.5±0.6 kcal/mol, respectively. The desorption activation energy of propane from Ir(110) is approximately 9.5 kcal/mol. These activation energies are compared to activation energies determined recently for ethane and propane adsorption on Ir(111), Ru(001), and Pt(110)-(1×2), and ethane activation on Ir(110).
Stroek, Kevin; Bouva, Marelle J; Schielen, Peter C J I; Vaz, Frédéric M; Heijboer, Annemieke C; de Jonge, Robert; Boelen, Anita; Bosch, Annet M
2018-03-21
Galactokinase (GALK) deficiency causes cataract leading to severe developmental consequences unless treated early. Because of the easy prevention and rapid reversibility of cataract with treatment, the Dutch Health Council advised to include GALK deficiency in the Dutch newborn screening program. The aim of this study is to establish the optimal screening method and cut-off value (COV) for GALK deficiency screening by performing a systematic review of the literature of screening strategies and total galactose (TGAL) values and by evaluating TGAL values in the first week of life in a cohort of screened newborns in the Netherlands. Systematic literature search strategies in OVID MEDLINE and OVID EMBASE were developed and study selection, data collection and analyses were performed by two independent investigators. A range of TGAL values measured by the Quantase Neonatal Total Galactose screening assay in a cohort of Dutch newborns in 2007 was evaluated. Eight publications were included in the systematic review. All four studies describing screening strategies used TGAL as the primary screening marker combined with galactose-1-phosphate uridyltransferase (GALT) measurement that is used for classical galactosemia screening. TGAL COVs of 2200 μmol/L, 1665 μmol/L and 1110 μmol/L blood resulted in positive predictive values (PPV) of 100%, 82% and 10% respectively. TGAL values measured in the newborn period were reported for 39 GALK deficiency patients with individual values ranging from 3963 to 8159 μmol/L blood and 2 group values with mean 8892 μmol/L blood (SD ± 5243) and 4856 μmol/L blood (SD ± 461). Dutch newborn screening data of 72,786 newborns from 2007 provided a median TGAL value of 110 μmol/L blood with a range of 30-2431 μmol/L blood. Based on TGAL values measured in GALK deficiency patients reported in the literature and TGAL measurements in the Dutch cohort by newborn screening we suggest to perform the GALK screening with TGAL as a primary marker with a COV of 2500 μmol/L blood, combined with GALT enzyme activity measurement as used in the classical galactosemia screening, to ensure detection of GALK deficiency patients and minimize false positive referrals. Copyright © 2018. Published by Elsevier Inc.
Assessment of dopamine receptor blockade by neuroleptic drugs in the living human brain
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wong, D.F.; Wagner, H.N. Jr.; Coyle, J.
1985-05-01
Positron emission tomography (PET) makes it possible to attempt to relate directly the antipsychotic effect of neuroleptic drugs and their blocking effect on dopamine receptors (D2) in vivo. The authors have examined the ability of haloperidol (HAL) and molindone (MOL) to block the binding of C-11 n-methylspiperone (NMSP) in 6 normal subjects. A dose of 0.05 mg/kg of HAL resulted in a 68% drop in the slope of the caudate/cerebellum (Ca/Cb) vs. time. This slope is related to the rate of specific binding of NMSP to the receptor. A dose response was seen with both drugs. With increasing doses ofmore » HAL from .05 to 0.082 mg/kg, CA/Cb vs. time slope fell from .235 to .156/min. (N=4), progressively. Similarly with increasing doses of MOL of .16-.44 mg/kg slopes decreased from .0335 to .0155/min. (N=4). Similar degrees of post injection Ca/Cb ratio were produced with quantities of MOL and HAL administered in the oral dose ratio of doses 3-5:1 times greater than HAL. This is also the dose ratio at which we found similar dopamine receptor blockade by PET in vivo. A question that arises is why the in vitro affinity of HAL for D2 is 30 times greater than that of MOL in the human brain. The results raise the possibility that MOL metabolites are not only active in blocking D2 but indeed may possibly be more potent than MOL itself. It also helps confirm the site of action of MOL and its in vivo metabolites.« less
Hüsler, B R.; Blum, J W.
2001-05-01
There is marked endogenous production of nitrate in young calves. Here we have studied the contribution of exogenous nitrate and nitrite to plasma concentrations and urinary excretion of nitrite and nitrate in milk-fed calves. In experiment 1, calves were fed 0 or 200 &mgr;mol nitrate or nitrite/kg(0.75) or 100 &mgr;mol nitrite plus 100 &mgr;mol nitrate/kg(0.75) with milk for 3 d. In experiment 2, calves were fed 400 &mgr;mol nitrate or nitrite/kg(0.75) with milk for 1 d. Plasma nitrate rapidly and comparably increased after feeding nitrite, nitrate or nitrite plus nitrate. The rise of plasma nitrate was greater if 400 than 200 &mgr;mol nitrate or nitrite/kg(0.75) were fed. Plasma nitrate decreased slowly after the 3-d administration of 200 &mgr;mol nitrate or nitrite/kg(0.75) and reached pre-experimental concentrations 4 d later. Urinary nitrate excretions nearly identically increased if nitrate, nitrite or nitrite plus nitrate were administered and excreted amounts were greater if 400 than 200 &mgr;mol nitrate or nitrite/kg(0.75) were fed. After nitrite ingestion plasma nitrite only transiently increased after 2 and 4 h and urinary excretion rates remained unchanged. Plasma nitrate concentration remained unchanged if milk was not supplemented with nitrite or nitrate. Nitrate concentrations were stable for 24 h after addition of nitrite to full blood in vitro, whereas nitrite concentrations decreased within 2 h. In conclusion, plasma nitrate concentrations and urinary nitrate excretions are enhanced dose-dependently by feeding low amounts of nitrate and nitrite, whereas after ingested nitrite only a transient and small rise of plasma nitrite is observed because of rapid conversion to nitrate.
Hellgren, Margareta; Hjörleifsdottir Steiner, Kristin; Bennet, Louise
2017-08-01
To explore and compare sensitivity and specificity for HbA1c ≥48mmol/mol as a predictor for type 2 diabetes mellitus (T2DM) in two populations with different ethnicity and to examine the predictive value of two levels of HbA1c (≥42mmol/mol, ≥39mmol/mol) for prediabetes in these populations. Four cohorts were examined with an oral glucose tolerance test. (1) The MEDIM Study (n=1991 individuals of Swedish and Iraqi ancestry); (2) The Skaraborg Project (n=1327 individuals of Swedish ancestry); (3) The 4-D study (n=424 individuals of Swedish, Iraqi and Turkish ancestry); (4) The Flemingsberg study (n=212 participants of Turkish ancestry). HbA1c ≥48mmol/mol had a sensitivity for T2DM of 31% and 25% respectively in individuals of Middle-East and Swedish ancestry. The positive and negative predictive value was high in both populations (70.3, 96.4 and 96.2, 97.6 respectively). Using HbA1c ≥42mmol/mol and ≥39mmol/mol as a predictor for prediabetes gave a sensitivity of 17% and 36% in individuals of Middle-East and 15% and 34% in individuals of Swedish ancestry. Even if HbA1c ≥48mmol/mol is a valuable diagnostic tool, it is a blunt and insensitive tool for screening and would exclude most people with T2DM, independent of ancestry and age. HbA1c is an inefficient way to detect individuals with prediabetes. Copyright © 2017 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.
Tang, Ning; Skibsted, Leif H
2017-08-02
The iron(IV) binding protein ferrylmyoglobin, MbFe(IV)═O, was found to be reduced by tyrosine based food components in aqueous solution through a sequential proton loss electron transfer reaction mechanism without binding to the protein as confirmed by isothermal titration calorimetry. Dopamine and epinephrine are the most efficient food components reducing ferrylmyoglobin to oxymyoglobin, MbFe(II)O 2 , and metmyoglobin, MbFe(III), as revealed by multivariate curve resolution alternating least-squares with second order rate constants of 33.6 ± 2.3 L/mol/s (ΔH ⧧ of 19 ± 5 kJ/mol, ΔS ⧧ of -136 ± 18 J/mol K) and 228.9 ± 13.3 L/mol/s (ΔH ⧧ of 110 ± 7 kJ/mol, ΔS ⧧ of 131 ± 25 J/mol K), respectively, at pH 7.4 and 25 °C. The other tyrosine based food components were found to reduce ferrylmyoglobin to metmyoglobin with similar reduction rates at pH 7.4 and 25 °C. These reduction reactions were enhanced by protonation of ferrylmyoglobin and facilitated proton transfer at acidic conditions. Enthalpy-entropy compensation effects were observed for the activation parameters (ΔH ⧧ and ΔS ⧧ ), indicating the common reaction mechanism. Moreover, principal component analysis combined with heat map were performed to understand the relationship between density functional theory calculated molecular descriptors and kinetic data, which was further modeled by partial least squares for quantitative structure-activity relationship analysis. In addition, a three tyrosine residue containing protein, lysozyme, was also found to be able to reduce ferrylmyoglobin with a second order rate constant of 66 ± 28 L/mol/s as determined by a competitive kinetic method.
Spectrofluorimetric determination of cefixime using terbium-danofloxacin probe
Manzoori, Jamshid L.; Amjadi, Mohammad; Soltani, Naser; Jouyban, Abolghasem
2014-01-01
Objective(s): Cefixime (Cfx), is a semi-synthetic third-generation oral cephalosporin antibiotic that is prescribed for the treatment of susceptible infections. There are some procedures for the determination of Cfx in pharmaceutical formulations and biological samples. Herein a spectrofluorimetric method was proposed for Cfx determination based on the fluorescence quenching of terbium-danofloxacin (Tb3+-Dano) in the presence of Cfx. Materials and Methods: Cfx was detected based on fluorescence quenching of terbium-danofloxacin (Tb3+-Dano) in the presence of Cfx with maximum excitation and emission wavelengths at 347 nm and 545 nm, respectively. The quenched fluorescence intensity of Tb3+- Dano system is proportional to the concentration of Cfx. The optimum conditions for the determination of Cfx were studied. Results: The maximum response was achieved under optimum conditions of [Tris buffer]= 0.008 mol/l (pH 6.5), [Tb3+]=1×10-4 mol/l and [Dano]=1×10-4 mol/l. The developed method was evaluated in terms of accuracy, precision and limit of detection. The linear concentration ranges for quantification of Cfx were 8.8×10-8-8.8×10-7 mol/l and 1.1×10-7-8.8×10-7 mol/l in standard and human serum samples with the detection limits (S/N=3) of 2.8×10-8 mol/l and 3.9×10-8 mol/l, respectively. The Cfx was determined in pharmaceutical tablets and spiked serum samples and the results were satisfactory. Conclusion: This method is simple, practical and relatively interference-free for determination of Cfx in pharmaceutical tablets and serum samples. PMID:24904718
Water dissociative adsorption on NiO(111): Energetics and structure of the hydroxylated surface
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Wei; Bajdich, Michal; Carey, Spencer
The energetics of the reactions of water with metal oxide surfaces are of tremendous interest for catalysis, electrocatalysis, and geochemistry, yet the energy for the dissociative adsorption of water was only previously measured on one well-defined oxide surface, iron oxide. In the present paper, the enthalpy of the dissociative adsorption of water is measured on NiO(111)-2 × 2 at 300 K using single-crystal adsorption calorimetry. The differential heat of dissociative adsorption decreases with coverage from 170 to 117 kJ/mol in the first 0.25 ML of coverage. Water adsorbs molecularly on top of that, with a heat of ~92 kJ/mol. Densitymore » functional theory (DFT) calculations reproduce the measured energies well (all within 17 kJ/mol) and provide insight into the atomic-level structure of the surfaces studied experimentally. They show that the oxygen-terminated O-octo(2 × 2) structure is the most stable NiO(111)-2 × 2 termination and gives reaction energies with water that are more consistent with the calorimetry results than the metal-terminated surface. They show that water adsorbs dissociatively on this (2 × 2)-O-octo surface to produce a hydroxyl-covered surface with a heat of adsorption of 171 ± 5 kJ/mol in the low-coverage limit (very close to 170 kJ/mol experimentally) and an integral heat that decreases by 14 kJ/mol up to saturation (compared to ~30 kJ/mol experimentally). As a result, sensitivity of this reaction’s energy to choice of DFT method is tested using a variety of different exchange correlation functionals, including HSE06, and found to be quite weak.« less
Water dissociative adsorption on NiO(111): Energetics and structure of the hydroxylated surface
Zhao, Wei; Bajdich, Michal; Carey, Spencer; ...
2016-09-19
The energetics of the reactions of water with metal oxide surfaces are of tremendous interest for catalysis, electrocatalysis, and geochemistry, yet the energy for the dissociative adsorption of water was only previously measured on one well-defined oxide surface, iron oxide. In the present paper, the enthalpy of the dissociative adsorption of water is measured on NiO(111)-2 × 2 at 300 K using single-crystal adsorption calorimetry. The differential heat of dissociative adsorption decreases with coverage from 170 to 117 kJ/mol in the first 0.25 ML of coverage. Water adsorbs molecularly on top of that, with a heat of ~92 kJ/mol. Densitymore » functional theory (DFT) calculations reproduce the measured energies well (all within 17 kJ/mol) and provide insight into the atomic-level structure of the surfaces studied experimentally. They show that the oxygen-terminated O-octo(2 × 2) structure is the most stable NiO(111)-2 × 2 termination and gives reaction energies with water that are more consistent with the calorimetry results than the metal-terminated surface. They show that water adsorbs dissociatively on this (2 × 2)-O-octo surface to produce a hydroxyl-covered surface with a heat of adsorption of 171 ± 5 kJ/mol in the low-coverage limit (very close to 170 kJ/mol experimentally) and an integral heat that decreases by 14 kJ/mol up to saturation (compared to ~30 kJ/mol experimentally). As a result, sensitivity of this reaction’s energy to choice of DFT method is tested using a variety of different exchange correlation functionals, including HSE06, and found to be quite weak.« less
NASA Astrophysics Data System (ADS)
Lin, Y. H.; Raghunath, P.; Lin, M. C.
2016-01-01
The adsorption and dissociation mechanisms of SiHx(x = 1-4) species on W(1 1 1) surface have been investigated by using the periodic density functional theory with the projector-augmented wave approach. The adsorption of all the species on four surface sites: top (T), bridge (B), shallow (S), and deep (D) sites have been analyzed. For SiH4 on a top site, T-SiH4(a), it is more stable with an adsorption energy of 2.6 kcal/mol. For SiH3, the 3-fold shallow site is most favorable with adsorption energy of 46.0 kcal/mol. For SiH2, its adsorption on a bridge site is most stable with 73.0 kcal/mol binding energy, whereas for SiH and Si the most stable adsorption configurations are on 3-fold deep sites with very high adsorption energies, 111.8 and 134.7 kcal/mol, respectively. The potential energy surfaces for the dissociative adsorption of all SiHx species on the W(1 1 1) surface have been constructed using the CINEB method. The barriers for H-atom migration from SiHx(a) to its neighboring W atoms, preferentially on B-sites, were predicted to be 0.4, 1.0, 4.5 and, 8.0 kcal/mol, respectively, for x = 4, 3, 2, and 1, respectively. The adsorption energy of the H atom on a bridge site on the clean W(1 1 1) surface was predicted to be 65.9 kcal/mol, which was found to be slightly affected by the co-adsorption of SiHx-1 within ± 1 kcal/mol.
NASA Astrophysics Data System (ADS)
Zainudin, C. N.; Hisam, R.; Yusof, M. I. M.; Yahya, A. K.; Halimah, M. K.
2017-10-01
Ternary germanate glasses (90 - x)GeO2-xNa2O-10PbO (x = 10-30 mol%) have been prepared by the melt-quenching method. Density, ρ increased with Na2O content up to maxima at 20 mol% while molar volume, V a showed an opposite trend to the density, with a minima at 20 mol% of Na2O content indicating the presence of the germanate anomaly. Ultrasonic velocity measurements showed both longitudinal, v l and shear, v s velocities increased up to 20 mol% before decreasing with further addition of Na2O. Independent longitudinal, L and shear, G moduli along with Young’s modulus, Y, mean sound velocity, v m, Debye temperature, θ D, and hardness, H recorded maximum values at 20 mol% of Na2O content which were suggested to be related to the germanate anomaly. Structural modification occurring due to conversion of six-membered GeO4 rings to three-membered rings of GeO4 changed bond density and compactness of the glass systems and caused the increase in rigidity and stiffness of the glasses. Beyond 20 mol% of Na2O, the decrease in the elastic moduli was due to depolymerization of the glass network. Meanwhile, optical energy gap, E opt exhibited a minima at 20 mol% whereas Urbach energy, E U and refractive index, n showed a maxima at the same concentration, thereby indicating variation in polarizability due to changes in concentration of bridging and non-bridging oxygen.
Energetics of formic acid conversion to adsorbed formates on Pt(111) by transient calorimetry.
Silbaugh, Trent L; Karp, Eric M; Campbell, Charles T
2014-03-12
Carboxylates adsorbed on solid surfaces are important in many technological applications, ranging from heterogeneous catalysis and surface organo-functionalization to medical implants. We report here the first experimentally determined enthalpy of formation of any surface bound carboxylate on any surface, formate on Pt(111). This was accomplished by studying the dissociative adsorption of formic acid on oxygen-presaturated (O-sat) Pt(111) to make adsorbed monodentate and bidentate formates using single-crystal adsorption calorimetry. The integral heat of molecular adsorption of formic acid on clean Pt(111) at 100 K is 62.5 kJ/mol at 0.25 monolayer (ML). On O-sat Pt(111), the integral heat of the dissociative adsorption of formic acid to make monodentate formate (HCOOmon,ad) plus the water-hydroxyl complex ((H2O-OH)ad) was found to be 76 kJ/mol at 3/8 ML and 100-150 K. Similarly, its integral heat of dissociative adsorption to make bidentate formate (HCOObi,ad) plus (H2O-OH)ad was 106 kJ/mol at 3/8 ML and 150 K. These heats give the standard enthalpies of formation of adsorbed monodentate and bidentate formate on Pt(111) to be -354 ± 5 and -384 ± 5 kJ/mol, respectively, and their net bond enthalpies to the Pt(111) surface to be 224 ± 13 and 254 ± 13 kJ/mol, respectively. Coverage-dependent enthalpies of formation were used to estimate the enthalpy of the elementary reaction HCOOHad → HCOObi,ad + Had to be -4 kJ/mol at zero coverage and +24 kJ/mol at 3/8 ML.
Nakagami, Tomoko; Tanaka, Yuki; Oya, Junko; Kurita, Moritoshi; Isago, Chisato; Hasegawa, Yukiko; Ito, Arata; Hirota, Naoki; Tsuzura, Reika; Uchigata, Yasuko
2016-12-01
This study assessed pre-diabetes (pre-DM) cutoffs for HbA1c and fasting plasma glucose (FPG) that were associated with an increased risk of incident DM. We evaluated 2267 non-diabetic Japanese health-check examinees (HbA1c: <6.5% [<48mmol/mol] and FPG: <7.0mmol/L) who were 30-79 years old and were followed-up for 5 years. Incident DM was defined as HbA1c of ≥6.5% (≥48mmol/mol), FPG of ≥7.0mmol/L, or physician-diagnosed DM. During 11047 person-years, we identified 99 incident DM cases (4.3%). The incidence of DM increased with increasing baseline HbA1c or FPG levels, and the change points (95% confidence intervals) were 5.7% (5.6-5.7%; 39mmol/mol [38-39mmol/mol]) for HbA1c and 5.5mmol/L (5.5-5.6mmol/L) for FPG. The adjusted hazard ratios (HRs) for incident DM per one standard deviation-increase in HbA1c and FPG were 5.5 (4.4-6.8) and 4.0 (3.2-4.8), respectively. The adjusted HRs for incident DM were significantly higher at HbA1c of 5.7-6.4% (39-46mmol/mol) or FPG of 5.5-6.9mmol/L, compared to HbA1c of <5.7% (<39mmol/mol) or FPG of <5.5mmol/L. The lower cut-offs for pre-DM may be 5.7% (39mmol/mol) for HbA1c and 5.5mmol/L for FPG in this Japanese population. Copyright © 2016 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.
Rice, Austin J; Harrison, Alistair; Alvarez, Frances J D; Davidson, Amy L; Pinkett, Heather W
2014-05-23
Embedded in the plasma membrane of all bacteria, ATP binding cassette (ABC) importers facilitate the uptake of several vital nutrients and cofactors. The ABC transporter, MolBC-A, imports molybdate by passing substrate from the binding protein MolA to a membrane-spanning translocation pathway of MolB. To understand the mechanism of transport in the biological membrane as a whole, the effects of the lipid bilayer on transport needed to be addressed. Continuous wave-electron paramagnetic resonance and in vivo molybdate uptake studies were used to test the impact of the lipid environment on the mechanism and function of MolBC-A. Working with the bacterium Haemophilus influenzae, we found that MolBC-A functions as a low affinity molybdate transporter in its native environment. In periods of high extracellular molybdate concentration, H. influenzae makes use of parallel molybdate transport systems (MolBC-A and ModBC-A) to take up a greater amount of molybdate than a strain with ModBC-A alone. In addition, the movement of the translocation pathway in response to nucleotide binding and hydrolysis in a lipid environment is conserved when compared with in-detergent analysis. However, electron paramagnetic resonance spectroscopy indicates that a lipid environment restricts the flexibility of the MolBC translocation pathway. By combining continuous wave-electron paramagnetic resonance spectroscopy and substrate uptake studies, we reveal details of molybdate transport and the logistics of uptake systems that employ multiple transporters for the same substrate, offering insight into the mechanisms of nutrient uptake in bacteria. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.
Feng, Lidan; Watanabe, Takumi; Wang, Yi; Kichise, Tomoyasu; Fukuchi, Takeshi; Chen, Guo-Qiang; Doi, Yoshiharu; Inoue, Yoshio
2002-01-01
The comonomer-unit compositional distributions have been investigated for bacterial poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HH)] samples with 3HH unit content of 13.8, 18.0, 22.0, and 54.0 mol %. They were comonomer compositionally fractionated using chloroform/n-heptane mixed solvent at ambient temperature. The fractionation of P(3HB-co-18.0 mol %3HH) and P(3HB-co-22.0 mol % 3HH), which could not be carried out effectively at room temperature, were refractionated at 70 degrees C in the mixed solvent. Fractions with different 3HH unit content in a wide range (from 4.4 to 80.7 mol %) were obtained. By use of these fractions with narrow compositional distribution, the comonomer composition dependence of thermal properties was investigated by differential scanning calorimetry. The melting point (T(m)) and heat of fusion (DeltaH) decreased as the 3HH unit content increased in the range of low 3HH content (<40 mol %), while they increased as the 3HH unit content increased in the high 3HH content range (>70 mol %). The minimum T(m) and DeltaH values were found to exist at 3HH unit content of about 60 mol %. The glass transition temperature (T(g)) decreased linearly with the increase of 3HH unit content. The values of T(m), DeltaH, and T(g) of P(3HB-co-3HH)s were compared with those of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxypropionate), and poly(3-hydroxybutyrate-co-4-hydroxybutyrate), and the effects of comonomer types on the thermal properties were revealed.
Soluble Extract from Moringa oleifera Leaves with a New Anticancer Activity
Jung, Il Lae
2014-01-01
Moringa oleifera has been regarded as a food substance since ancient times and has also been used as a treatment for many diseases. Recently, various therapeutic effects of M. oleifera such as antimicrobial, anticancer, anti-inflammatory, antidiabetic, and antioxidant effects have been investigated; however, most of these studies described only simple biological phenomena and their chemical compositions. Due to the increasing attention on natural products, such as those from plants, and the advantages of oral administration of anticancer drugs, soluble extracts from M. oleifera leaves (MOL) have been prepared and their potential as new anticancer drug candidates has been assessed in this study. Here, the soluble cold Distilled Water extract (4°C; concentration, 300 µg/mL) from MOL greatly induced apoptosis, inhibited tumor cell growth, and lowered the level of internal reactive oxygen species (ROS) in human lung cancer cells as well as other several types of cancer cells, suggesting that the treatment of cancer cells with MOL significantly reduced cancer cell proliferation and invasion. Moreover, over 90% of the genes tested were unexpectedly downregulated more than 2-fold, while just below 1% of the genes were upregulated more than 2-fold in MOL extract-treated cells, when compared with nontreated cells. Since severe dose-dependent rRNA degradation was observed, the abnormal downregulation of numerous genes was considered to be attributable to abnormal RNA formation caused by treatment with MOL extracts. Additionally, the MOL extract showed greater cytotoxicity for tumor cells than for normal cells, strongly suggesting that it could potentially be an ideal anticancer therapeutic candidate specific to cancer cells. These results suggest the potential therapeutic implications of the soluble extract from MOL in the treatment of various types of cancers. PMID:24748376
Bai, Qifeng; Shao, Yonghua; Pan, Dabo; Zhang, Yang; Liu, Huanxiang; Yao, Xiaojun
2014-01-01
We designed a program called MolGridCal that can be used to screen small molecule database in grid computing on basis of JPPF grid environment. Based on MolGridCal program, we proposed an integrated strategy for virtual screening and binding mode investigation by combining molecular docking, molecular dynamics (MD) simulations and free energy calculations. To test the effectiveness of MolGridCal, we screened potential ligands for β2 adrenergic receptor (β2AR) from a database containing 50,000 small molecules. MolGridCal can not only send tasks to the grid server automatically, but also can distribute tasks using the screensaver function. As for the results of virtual screening, the known agonist BI-167107 of β2AR is ranked among the top 2% of the screened candidates, indicating MolGridCal program can give reasonable results. To further study the binding mode and refine the results of MolGridCal, more accurate docking and scoring methods are used to estimate the binding affinity for the top three molecules (agonist BI-167107, neutral antagonist alprenolol and inverse agonist ICI 118,551). The results indicate agonist BI-167107 has the best binding affinity. MD simulation and free energy calculation are employed to investigate the dynamic interaction mechanism between the ligands and β2AR. The results show that the agonist BI-167107 also has the lowest binding free energy. This study can provide a new way to perform virtual screening effectively through integrating molecular docking based on grid computing, MD simulations and free energy calculations. The source codes of MolGridCal are freely available at http://molgridcal.codeplex.com. PMID:25229694
Li, Jitao; Yang, Jiangang; Men, Yan; Zeng, Yan; Zhu, Yueming; Dong, Caixia; Sun, Yuanxia; Ma, Yanhe
2015-10-01
2-Deoxy-D-ribose 5-phosphate aldolase (DERA) accepts a wide variety of aldehydes and is used in de novo synthesis of 2-deoxysugars, which have important applications in drug manufacturing. However, DERA has low preference for non-phosphorylated substrates. In this study, DERA from Klebsiella pneumoniae (KDERA) was mutated to increase its enzyme activity and substrate tolerance towards non-phosphorylated polyhydroxy aldehyde. Mutant KDERA(K12) (S238D/F200I/ΔY259) showed a 3.15-fold improvement in enzyme activity and a 1.54-fold increase in substrate tolerance towards D-glyceraldehyde compared with the wild type. Furthermore, a whole-cell transformation strategy using resting cells of the BL21(pKDERA12) strain, containing the expressed plasmid pKDERA12, resulted in increase in 2-deoxy-D-ribose yield from 0.41 mol/mol D-glyceraldehyde to 0.81 mol/mol D-glyceraldehyde and higher substrate tolerance from 0.5 to 3 M compared to in vitro assays. With further optimization of the transformation process, the BL21(pKDERA12) strain produced 2.14 M (287.06 g/L) 2-deoxy-D-robose (DR), with a yield of 0.71 mol/mol D-glyceraldehyde and average productivity of 0.13 mol/L·h (17.94 g/L·h). These results demonstrate the potential for large-scale production of 2-deoxy-D-ribose using the BL21(pKDERA12) strain. Furthermore, the BL21(pKDERA12) strain also exhibited the ability to efficiently produce 2-deoxy-D-altrose from D-erythrose, as well as 2-deoxy-L-xylose and 2-deoxy-L-ribose from L-glyceraldehyde.
A remarkable solvent effect on the nuclearity of neutral titanium(IV)-based helicate assemblies.
Weekes, David Michael; Diebold, Carine; Mobian, Pierre; Huguenard, Clarisse; Allouche, Lionel; Henry, Marc
2014-04-22
The spontaneous self-assembly of a neutral circular trinuclear Ti(IV) -based helicate is described through the reaction of titanium(IV) isopropoxide with a rationally designed tetraphenolic ligand. The trimeric ring helicate was obtained after diffusion of n-pentane into a solution with dichloromethane. The circular helicate has been characterized by using single-crystal X-ray diffraction study, (13) C CP-MAS NMR and (1) H NMR DOSY solution spectroscopic, and positive electrospray ionization mass-spectrometric analysis. These analytical data were compared with those obtained from a previously reported double-stranded helicate that crystallizes in toluene. The trimeric ring was unstable in a pure solution with dichloromethane and transformed into the double-stranded helicate. Thermodynamic analysis by means of the PACHA software revealed that formation of the double-stranded helicates was characterized by ΔH(toluene)=-30 kJ mol(-1) and ΔS(toluene)=+357 J K(-1) mol(-1) , whereas these values were ΔH(CH2 Cl2 )=-75 kJ mol(-1) and ΔS(CH2 Cl2 )=-37 J K(-1) mol(-1) for the ring helicate. The transformation of the ring helicate into the double-stranded helicate was a strongly endothermic process characterized by ΔH(CH2 Cl2 )=+127 kJ mol(-1) and ΔH(n-pentane)=+644 kJ mol(-1) associated with a large positive entropy change ΔS=+1115 J K(-1) ⋅mol(-1) . Consequently, the instability of the ring helicate in pure dichloromethane was attributed to the rather high dielectric constant and dipole moment of dichloromethane relative to n-pentane. Suggestions for increasing the stability of the ring helicate are given. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Do older adults use the Method of Loci? Results from the ACTIVE Study
Gross, Alden L.; Brandt, Jason; Bandeen-Roche, Karen; Carlson, Michelle C.; Stuart, Elizabeth A.; Marsiske, Michael; Rebok, George W.
2013-01-01
Background The method of loci (MoL) is a complex visuospatial mnemonic strategy. Previous research suggests older adults could potentially benefit from using the MoL, but that it is too attentionally demanding for them to use in practice. We evaluated the hypotheses that training can increase the use of MoL, and that MoL use is associated with better memory. Methods We analyzed skip patterns on response forms for the Auditory Verbal Learning Test (AVLT) in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE, n=1,401) trial using 5 years of longitudinal follow-up. Results At baseline, 2% of participants skipped spaces. Fewer than 2% of control participants skipped spaces at any visit across 5 years, but 25% of memory-trained participants, taught the MoL, did so. Participants who skipped spaces used more serial clustering, a hallmark of the MoL (p<0.001). Trained participants who skipped spaces showed greater memory improvement after training than memory-trained participants who did not skip spaces (Cohen's d=0.84, P=0.007), and did not differ in the subsequent rate of long-term memory decline through up to 5 years of follow-up. Conclusion Despite being attentionally demanding, this study suggests that after training, the MoL is used by up to 25% of older adults, and that its use is associated with immediate memory improvement that was sustained through the course of follow-up. Findings are consistent with the notion that older adults balance complexity with novelty in strategy selection, and that changes in strategies used following memory training result in observable qualitative and quantitative differences in memory performance. PMID:24625044
NASA Astrophysics Data System (ADS)
Getoff, Nikola; Platzer, Isabel; Winkelbauer, Cornelia
1999-08-01
Using N •3 species as specific electron acceptor a defined ascorbate radical: AH •↔A •-+H + (λ max=360 nm, ɛ=3400 dm 3 mol -1 cm -1) is observed. The attack of DMSO •+ on vit.E results in a vit.E • radical ( k=1×10 9 dm 3 mol -1 s -1; λ max=425 nm, ɛ=2400 dm 3 mol -1 cm -1; 2 k=4.7×10 8 dm 3 mol -1 s -1). Vit.E-acetate leads to the formation of a radical cation (vit.E-ac •+). β-carotene reacts also with DMSO •+ forming a radical cation, β-car •+ ( k=1.75×10 8 dm 3 mol -1 s -1; λ max=942 nm, ɛ=14 600 dm 3 mol -1 cm -1), which probably leads to the formation of a dimer radical cation, (β-car) •+2 ( k=2.5×10 7 dm 3 mol -1 s -1). Using E.coli bacteria (AB1157) as a model system in vitro it was found that all three vitamins are rather efficient radiation protecting agents. They can also increase the activity of cytostatica, e.g., mitomycin C (MMC), by electron transfer process. The mixture of vit.E-ac and β-car acts contradictory, but adding vit.C to it a strong cooperative enhancement of the MMC activity is observed once again. A relationship between the pulse radiolysis and the radiation biological data is found and discussed. A possible explanation of the previously reported trials concerning the role of vit.E and β-car on the increased occurence of lung and other types of cancer in smokers and drinkers is presented.
Keen, C; Coldwell, M; McNally, K; Baldwin, P; McAlinden, J; Cocker, J
2012-08-13
This is a follow up survey of exposure to 4,4'-methylene-bis(2-chloroaniline) (MbOCA) and isocyanates in the UK polyurethane industry. Urine samples (n=446) were collected from 90 different workers. MbOCA levels were below the limit of detection in 170 samples and 26 were above the UK Biological Monitoring Guidance Value (BMGV) of 15 μmol MbOCA/mol creatinine. Detailed advice and guidance was given to each workplace at the end of the survey in 2008 and the 90% value reduced from 10 to 3 μmol MbOCA/mol creatinine in samples collected since. There was a positive correlation between glove contamination and urinary MbOCA and levels were dependent upon individual working practices especially how gloves were used. Of the 446 samples analysed for urinary metabolites of toluene diisocyanate 280 were below the detection limit and 126 were above the BMGV (1 μmol/mol creatinine). Of the 326 urine samples that were analysed for metabolites of methylenediphenyl diisocyanate, 270 were below the detection limit and 13 were above the BMGV for isocyanates. There was no correlation between urinary levels of isocyanates and MbOCA suggesting different routes of absorption, most likely inhalation and dermal respectively. Crown Copyright © 2011. Published by Elsevier Ireland Ltd. All rights reserved.
Xie, Guo-Jun; Liu, Bing-Feng; Ding, Jie; Wang, Qilin; Ma, Chao; Zhou, Xu; Ren, Nan-Qi
2016-12-01
Poor flocculation of photo fermentative bacteria resulting in continuous biomass washout from photobioreactor is a critical challenge to achieve rapid and stable hydrogen production. In this work, the aggregation of Rhodopseudomonas faecalis RLD-53 was successfully developed in a photobioreactor and the effects of different carbon sources on hydrogen production and aggregation ability were investigated. Extracellular polymeric substances (EPS) production by R. faecalis RLD-53 cultivated using different carbon sources were stimulated by addition of L-cysteine. The absolute ζ potentials of R. faecalis RLD-53 were considerably decreased with addition of L-cysteine, and aggregation barriers based on DLVO dropped to 15-43 % of that in control groups. Thus, R. faecalis RLD-53 flocculated effectively, and aggregation abilities of strain RLD-53 cultivated with acetate, propionate, lactate and malate reached 29.35, 32.34, 26.07 and 24.86 %, respectively. In the continuous test, hydrogen-producing activity was also promoted and reached 2.45 mol H 2 /mol lactate, 3.87 mol H 2 /mol propionate and 5.10 mol H 2 /mol malate, respectively. Therefore, the aggregation of R. faecalis RLD-53 induced by L-cysteine is independent on the substrate types, which ensures the wide application of this technology to enhance hydrogen recovery from wastewater dominated by different organic substrates.
Thermochemistry and gas-phase ion energetics of 2-hydroxy-4-methoxy-benzophenone (oxybenzone).
Lago, A F; Jimenez, P; Herrero, R; Dávalos, J Z; Abboud, J-L M
2008-04-10
We have investigated the thermochemistry and ion energetics of the oxybenzone (2-hydroxy-4-methoxy-benzophenone, C14H12O3, 1H) molecule. The following parameters have been determined for this species: gas-phase enthalpy for the of neutral molecule at 298.15K, (Delta(f)H0(m)(g) = -303.5 +/- 5.1 kJ x mol-1), the intrinsic (gas-phase) acidity (GA(1H) = 1402.1 +/- 8.4 kJ x mol-1), enthalpy of formation for the oxybenzone anion (Delta(f)H0(m)(1-,g) = -402.3 +/- 9.8 kJ x mol-1). We also have obtained the enthalpy of formation of, 4-hydroxy-4'-methoxybenzophenone (Delta(f)H0(m)(g) = -275.4 +/- 10 kJ x mol-1) and 3-methoxyphenol anion (Delta(f)H0(m)(C7H7O2-,g) = -317.7 +/- 8.7 kJ x mol-1). A reliable experimental estimation of enthalpy related to intramolecular hydrogen bonding in oxybenzone has also been obtained (30.1 +/- 6.3 kJ x mol-1) and compared with our theoretical calculations at the B3LYP/6-311++G** level of theory, by means of an isodesmic reaction scheme. In addition, heat capacities, temperature, and enthalpy of fusion have been determined for this molecule by differential scanning calorimetry.
H2O and CO2 fluxes at the floor of a boreal pine forest
NASA Astrophysics Data System (ADS)
Kulmala, Liisa; Launiainen, Samuli; Pumpanen, Jukka; Lankreijer, Harry; Lindroth, Anders; Hari, Pertti; Vesala, Timo
2008-04-01
We measured H2O and CO2 fluxes at a boreal forest floor using eddy covariance (EC) and chamber methods. Maximum evapotranspiration measured with EC ranged from 1.5 to 2.0mmol m-2 s-1 while chamber estimates depended substantially on the location and the vegetation inside the chamber. The daytime net CO2 exchange measured with EC (0-2μmol m-2 s-1) was of the same order as measured with the chambers. The nocturnal net CO2 exchange measured with the chambers ranged from 4 to 7μmol m-2 s-1 and with EC from ~4 to ~5μmol m-2 s-1 when turbulent mixing below the canopy was sufficient and the measurements were reliable. We studied gross photosynthesis by measuring the light response curves of the most common forest floor species and found the saturated rates of photosynthesis (Pmax) to range from 0.008 (mosses) to 0.184μmol g-1 s-1 (blueberry). The estimated gross photosynthesis at the study site based on average leaf masses and the light response curves of individual plant species was 2-3μmol m-2 s-1. At the same time, we measured a whole community with another chamber and found maximum gross photosynthesis rates from 4 to 7μmol m-2 s-1.
N-(2-{[5-Bromo-2-(piperidin-1-yl)pyrimidin-4-yl]sulfanyl}-4-methoxyphenyl)benzenesulfonamide
Kumar, Mohan; Mallesha, L.; Sridhar, M. A.; Kapoor, Kamini; Gupta, Vivek K.; Kant, Rajni
2012-01-01
The title compound, C22H23BrN4O3S2, crystallizes with two molecules, A and B, in the asymmetric unit. In one of these, the methoxy group is disordered over two sets of sites in a 0.565 (9):0.435 (9) ratio. The benzene rings bridged by the sulfonamide group are tilted relative to each other by 37.4 (1) and 56.1 (1)° in molecules A and B, respectively, while the dihedral angles between the sulfur-bridged pyrimidine and benzene rings are 72.4 (1) and 70.2 (1)° for A and B, respectively. The piperidine ring adopts a chair conformation in both molecules. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds occur for both A and B; the dimers are linked into [010] chains by C—H⋯O hydrogen bonds. The crystal structure also features inversion-generated aromatic π–π stacking interactions between the pyrimidine rings for both molecules [centroid–centroid distances = 3.412 (2) (molecule A) and 3.396 (2) Å (molecule B)]. PMID:23284517
Phase stability and photocatalytic activity of Zr-doped anatase synthesized in miniemulsion
NASA Astrophysics Data System (ADS)
Schiller, Renate; Weiss, Clemens K.; Landfester, Katharina
2010-10-01
A series of mesoporous anatase-type TiO2 doped with zirconium (0-50 mol% Zr) was synthesized by combining the sol-gel process with the inverse miniemulsion technique. Nanoparticles between 100 and 300 nm were directly prepared from acidic precursor solutions of titanium glycolate (EGMT) and zirconium isopropoxide. The miniemulsion technique is a simple and convenient method to synthesize nanoparticles of homogeneous size because the reactions (here hydrolysis and condensation) take place in the confined space of nanodroplets (several hundreds of nanometres) and therefore in a highly controlled manner. For low doping levels (0-7.1 mol% Zr), ZrxTi1 - xO2 solid solutions were formed where Zr was uniformly dispersed into the anatase framework. For higher amounts of zirconium (Zr >= 7.1 mol%), the crystallization of zirconium titanate (ZrTiO4) occurred at a low temperature of 650 °C and it was obtained as a pure material for 47.4 mol% <= Zr <= 50 mol%. The influence of the amount of zirconium on the crystallinity, crystallite size, phase composition and stability, morphology and specific surface area was investigated. For the characterization transmission electron microscopy (TEM), x-ray diffraction (XRD), nitrogen sorption (BET) and inductively coupled plasma-optical emission spectrometry (ICP-OES) were used. The photocatalytic activity of the crystalline mixed oxides (0-9.4 mol% Zr) was examined for the degradation of methylene blue under UV irradiation.
Reaction mechanism of guanidinoacetate methyltransferase, concerted or step-wise
Zhang, Xiaodong; Bruice, Thomas C.
2006-01-01
We describe a quantum mechanics/molecular mechanics investigation of the guanidinoacetate methyltransferase catalyzed reaction, which shows that proton transfer from guanidinoacetate (GAA) to Asp-134 and methyl transfer from S-adenosyl-l-methionine (AdoMet) to GAA are concerted. By self-consistent-charge density functional tight binding/molecular mechanics, the bond lengths in the concerted mechanism's transition state are 1.26 Å for both the OD1 (Asp-134)–HE (GAA) and HE (GAA)–NE (GAA) bonds, and 2.47 and 2.03 Å for the S8 (AdoMet)–C9 (AdoMet) and C9 (AdoMet)–NE (GAA) bonds, respectively. The potential-energy barrier (ΔE‡) determined by single-point B3LYP/6–31+G*//MM is 18.9 kcal/mol. The contributions of the entropy (−TΔS‡) and zero-point energy corrections Δ(ZPE)‡ by normal mode analysis are 2.3 kcal/mol and −1.7 kcal/mol, respectively. Thus, the activation enthalpy of this concerted mechanism is predicted to be ΔH‡ = ΔE‡ + Δ(ZPE)‡ = 17.2 kcal/mol. The calculated free-energy barrier for the concerted mechanism is ΔG‡ = 19.5 kcal/mol, which is in excellent agreement with the value of 19.0 kcal/mol calculated from the experimental rate constant (3.8 ± 0.2·min−1). PMID:17053070
Removal of toxic Congo red dye from water employing low-cost coconut residual fiber.
Rani, K C; Naik, Aduja; Chaurasiya, Ram Saran; Raghavarao, K S M S
2017-05-01
The coconut residual fiber (CRF) is the major byproduct obtained during production of virgin coconut oil. Its application as a biosorbent for adsorption of Congo red was investigated. The CRF was subjected to different pretreatments, namely, pressure cooking, hexane treatment, acid treatment and their combinations. The pretreatment of CRF with the combination of hexane, acid, and pressure cooking resulted in the highest degree of adsorption. The equilibrium data were analyzed and found to fit best to both Langmuir and Freundlich isotherms. Thermodynamic parameters such as standard free energy (ΔG 0 kJ mol -1 ), standard enthalpy (ΔH 0 , kJ mol -1 ) and standard entropy (ΔS 0 , kJ mol -1 K -1 ) of the systems were calculated by using the Langmuir constant. The ΔG 0 , ΔH 0 and ΔS 0 were found to be 16.51 kJ mol -1 , -19.39 kJ mol -1 and -0.12 kJ mol -1 K -1 , respectively, at 300 K. These thermodynamic parameters suggest the present adsorption process to be non-spontaneous and exothermic. The adsorption process was observed to follow pseudo-second-order kinetics. The results suggest that CRF has potential to be a biosorbent for the removal of hazardous material (Congo red dye) with a maximum adsorption capacity of 128.94 mg g -1 at 300 K.
Occupational tellurium exposure and garlic odour.
Berriault, C J; Lightfoot, N E
2011-03-01
Few studies have considered garlic odour as a socially important outcome of occupational tellurium (Te) exposure or concurrent exposures, and most known guidelines focus on other signs and symptoms (e.g. weight loss and somnolence). This study considers workers exposed to tellurium and selenium (Se) at an Ontario, Canada silver refinery. To establish the relation of urinary tellurium concentrations to reporting garlic odour, while considering other work-related factors such as concurrent urinary selenium concentrations. Historical surveillance records of urinary analyses for tellurium and selenium concentrations (μmol Te or Se/mol creatinine in urine) and symptom self-reports were used. Records were available from December 1986 to June 2002. Logistic regression models were fitted using age at sampling, tellurium and selenium urine concentration and duration of employment. Individual main effects were age adjusted and the final model was fitted for tellurium and selenium urine concentration and duration of employment. Urinary tellurium concentration was significantly associated with garlic odour reporting (odds ratio = 1.74, 95% confidence interval 1.01-2.97, P < 0.05). Furthermore, the likelihood of reporting garlic odour rose as workers reached urinary tellurium concentrations >1 μmol/mol creatinine. Tellurium urinary concentrations of <1 μmol/mol creatinine appear to limit, but not eliminate, the likelihood of reporting garlic odour. Future studies should consider the effect of concurrent selenium exposure as well as other workplace factors and hygiene.
Li, Ning; Du, Jian; Yang, Jing; Fan, Qiang; Tian, Wen
2017-11-01
A gas standard mixture containing 22 chlorinated hydrocarbons in high purity nitrogen was prepared using a two-step weighing method and a gasifying apparatus developed in-house. The concentration of each component was determined using a gas chromatograph with flame ionization detection (GC/FID). Linear regression analysis of every component was performed using the gas standard mixture with concentrations ranging from 1 to 10 μmol/mol, showing the complete gasification of volatile organic compound (VOCs) species in a selected cylinder. Repeatability was also examined to ensure the reliability of the preparation method. In addition, no significant difference was observed between domestic treated and imported treated cylinders, which were conducive to reduction of the cost of raw materials. Moreover, the results of stability testing at different pressures and long-term stability tests indicated that the gas standard at 1 μmol/mol level with relative expanded uncertainties of 5% was stable above 2 MPa for a minimum of 12 months. Finally, a quantity comparison was conducted between the gas standard and a commercial gas standard from Scott Specialty Gases (now Air Liquide America Specialty Gases). The excellent agreement of every species suggested the favorable accuracy of our gas standard. Therefore, this reference material can be applied to routine observation of VOCs and for other purposes.
Zou, Wen; Ran, Xu; Liang, Jie; Chen, Hezhong; Luo, Jiaoming
2012-12-01
Strontium added into porous hydroxyaptite ceramics has the functions of improving its osseointegration, decreasing its dissolution rate and improving the bone density. Strontium-containing hydroxyaptite (Sr-HA) ceramics has been used as bone replacement and scaffold to treat the osteoporosis and bone default in clinic, but the mechanism of interfacial tissue response caused by the trace element Sr in Sr-HA ceramics still remains to be further studied. Four types of Sr-HA ceramic samples with different contents of Sr were prepared by microwave plasma sintering for testing the response of the soft tissue implanted in dog muscles in our laboratory. The contents of Sr element in the samples are 0 mol%, 1 mol%, 5 mol%, and 7 mol%, respectively. The samples were implanted in the muscle of the dogs for 4 weeks, 8 weeks and 12 weeks, respectively. The histological observations at the end of each period showed that the irritant ranking increased with the content of Sr in Sr-HA ceramics at the end of 12 weeks, and there were rich bone tissue in Sr-HA ceramic samples with 5 mol% Sr element. The overdose of element Sr is harmful to soft tissues. When the content of Sr in Sr-HA ceramic was below 5 mol%, the soft tissue response was very slight and the new bones were induced to grow well.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cao, Lingyun; Lin, Zekai; Shi, Wenjie
The dimensionality dependency of resonance energy transfer is of great interest due to its importance in understanding energy transfer on cell membranes and in low-dimension nanostructures. Light harvesting two-dimensional metal–organic layers (2D-MOLs) and three-dimensional metal–organic frameworks (3D-MOFs) provide comparative models to study such dimensionality dependence with molecular accuracy. Here we report the construction of 2D-MOLs and 3D-MOFs from a donor ligand 4,4',4''-(benzene-1,3,5-triyl-tris(ethyne-2,1-diyl))tribenzoate (BTE) and a doped acceptor ligand 3,3',3''-nitro-4,4',4''-(benzene-1,3,5-triyl-tris(ethyne-2,1-diyl))tribenzoate (BTE-NO2). These 2D-MOLs and 3D-MOFs are connected by similar hafnium clusters, with key differences in the topology and dimensionality of the metal–ligand connection. Energy transfer from donors to acceptors through themore » 2D-MOL or 3D-MOF skeletons is revealed by measuring and modeling the fluorescence quenching of the donors. We found that energy transfer in 3D-MOFs is more efficient than that in 2D-MOLs, but excitons on 2D-MOLs are more accessible to external quenchers as compared with those in 3D-MOFs. These results not only provide support to theoretical analysis of energy transfer in low dimensions, but also present opportunities to use efficient exciton migration in 2D materials for light-harvesting and fluorescence sensing.« less
Zhu, Xinna; Tan, Zaigao; Xu, Hongtao; Chen, Jing; Tang, Jinlei; Zhang, Xueli
2014-07-01
Reducing equivalents are an important cofactor for efficient synthesis of target products. During metabolic evolution to improve succinate production in Escherichia coli strains, two reducing equivalent-conserving pathways were activated to increase succinate yield. The sensitivity of pyruvate dehydrogenase to NADH inhibition was eliminated by three nucleotide mutations in the lpdA gene. Pyruvate dehydrogenase activity increased under anaerobic conditions, which provided additional NADH. The pentose phosphate pathway and transhydrogenase were activated by increased activities of transketolase and soluble transhydrogenase SthA. These data suggest that more carbon flux went through the pentose phosphate pathway, thus leading to production of more reducing equivalent in the form of NADPH, which was then converted to NADH through soluble transhydrogenase for succinate production. Reverse metabolic engineering was further performed in a parent strain, which was not metabolically evolved, to verify the effects of activating these two reducing equivalent-conserving pathways for improving succinate yield. Activating pyruvate dehydrogenase increased succinate yield from 1.12 to 1.31mol/mol, whereas activating the pentose phosphate pathway and transhydrogenase increased succinate yield from 1.12 to 1.33mol/mol. Activating these two pathways in combination led to a succinate yield of 1.5mol/mol (88% of theoretical maximum), suggesting that they exhibited a synergistic effect for improving succinate yield. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Smart, D. R.; Chatterton, N. J.; Bugbee, B.
1994-01-01
We grew 2.4 m2 wheat canopies in a large growth chamber under high photosynthetic photon flux (1000 micromoles m-2 s-1) and using two CO2 concentrations, 360 and 1200 micromoles mol-1. Photosynthetically active radiation (400-700 nm) was attenuated slightly faster through canopies grown in 360 micromoles mol-1 than through canopies grown in 1200 micromoles mol-1, even though high-CO2 canopies attained larger leaf area indices. Tissue fractions were sampled from each 5-cm layer of the canopies. Leaf tissue sampled from the tops of canopies grown in 1200 micromoles mol-1 accumulated significantly more total non-structural carbohydrate, starch, fructan, sucrose, and glucose (p < 0.05) than for canopies grown in 360 micromoles mol-1. Non-structural carbohydrate did not significantly increase in the lower canopy layers of the elevated CO2 treatment. Elevated CO2 induced fructan synthesis in all leaf tissue fractions, but fructan formation was greatest in the uppermost leaf area. A moderate temperature reduction of 10 degrees C over 5 d increased starch, fructan and glucose levels in canopies grown in 1200 micromoles mol-1, but concentrations of sucrose and fructose decreased slightly or remained unchanged. Those results may correspond with the use of fructosyl-residues and release of glucose when sucrose is consumed in fructan synthesis.
Hu, Xuefu; Wang, Zi; Lin, Bangjiang; Zhang, Cankun; Cao, Lingyun; Wang, Tingting; Zhang, Jingzheng; Wang, Cheng; Lin, Wenbin
2017-06-22
A metal-organic layer (MOL) is a new type of 2D material that is derived from metal-organic frameworks (MOFs) by reducing one dimension to a single layer or a few layers. Tetraphenylethylene-based tetracarboxylate ligands (TCBPE), with aggregation-induced emission properties, were assembled into the first luminescent MOL by linking with Zr 6 O 4 (OH) 6 (H 2 O) 2 (HCO 2 ) 6 clusters. The emissive MOL can replace the lanthanide phosphors in white light emitting diodes (WLEDs) with remarkable processability, color rendering, and brightness. Importantly, the MOL-WLED exhibited a physical switching speed three times that of commercial WLEDs, which is crucial for visible-light communication (VLC), an alternative wireless communication technology to Wi-Fi and Bluetooth, by using room lighting to carry transmitted signals. The short fluorescence lifetime (2.6 ns) together with high quantum yield (50 %) of the MOL affords fast switching of the assembled WLEDs for efficient information encoding and transmission. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Melaminium nitrate–melamine–water (1/1/1)
Adam, Farook; Lin, Sek Kei; Hello, Kasim Mohammed; Hemamalini, Madhukar; Fun, Hoong-Kun
2010-01-01
In the crystal structure of the title salt, C3H7N6 +·NO3 −·C3H6N6·H2O, the asymmetric unit consists of two neutral melamine (1,3,5-triazine-2,4,6-triamine) molecules, two melaminium cations, two nitrate anions and two solvent water molecules. One of the nitrate anions is disordered over two sets of positions, with a refined occupancy ratio of 0.909 (3):0.091 (3). The cations and neutral molecules are approximately planar, with maximum deviations of 0.018 (2), 0.024 (2), 0.019 (2) and 0.007 (2) Å for each, respectively. In the crystal structure, melaminium cations and netural melamine molecules self-assemble via N—H⋯N hydrogen bonds to form a supramolecular hexagonal-shaped motif. In addition, the nitrate anions and water molecules are connected by N—H⋯O hydrogen bonds to form a three-dimensional network. PMID:21589188
pH dependence of the dissociation of multimeric hemoglobin probed by high hydrostatic pressure.
Bispo, Jose A C; Santos, Jose L R; Landini, Gustavo F; Goncalves, Juliana M; Bonafe, Carlos F S
2007-02-01
We investigated the thermodynamic features of the classic alkaline dissociation of multimeric hemoglobin (3.1 MDa) from Glossoscolex paulistus (Annelidea) using high hydrostatic pressure. Light scattering measurements up to microscopic thermodynamic equilibrium indicated a high pH dependency of dissociation and association. Electron microscopy and gel filtration corroborated these findings. The volume change of dissociation decreased in absolute values from -48.0 mL/mol of subunit at pH 6.0 to -19.2 mL/mol at pH 9.0, suggesting a lack of protein interactions under alkaline conditions. Concomitantly, an increase in pH reduced the Gibbs free energy of dissociation from 37.7 to 27.5 kJ/mol of subunit. The stoichiometry of proton release calculated from the pressure-induced dissociation curves was +0.602 mol of H(+)/mol of subunit. These results provide a direct quantification of proton participation in stabilizing the aggregated state of the hemoglobin, and contribute to our understanding of protein-protein interactions and of the surrounding conditions that modulate the process of aggregation.
Electrophoresis-chemiluminescence detection of phenols catalyzed by hemin.
Shu, Lu; Zhu, Jinkun; Wang, Qingjiang; He, Pingang; Fang, Yuzhi
2014-09-01
Based on the catalytic activity of hemin, an efficient biocatalyst, an indirect capillary electrophoresis-chemiluminescence (CE-CL) detection method for phenols using a hemin-luminol-hydrogen peroxide system was developed. Through a series of static injection experiments, hemin was found to perform best in a neutral solution rather than an acidic or alkaline medium. Although halide ions such as Br(-) and F(-) could further enhance the CL signal catalyzed by hemin, it is difficult to apply these conditions to this CE-CL detection system because of the self-polymerization of hemin, as it hinders the CE process. The addition of concentrated ammonium hydroxide to an aqueous/dimethyl sulfoxide solution of hemin-luminol afforded a stable CE-CL baseline. The indirect CE-CL detection of five phenols using this method gave the following limits of detections: 4.8 × 10(-8) mol/L (o-sec-butylphenol), 4.9 × 10(-8) mol/L (o-cresol), 5.4 × 10(-8) mol/L (m-cresol), 5.3 × 10(-8) mol/L (2,4-dichlorophenol) and 7.1 × 10(-8) mol/L (phenol). Copyright © 2013 John Wiley & Sons, Ltd.
Inosine-5'-monophosphate is a candidate agent to resolve rigor mortis of skeletal muscle.
Matsuishi, Masanori; Tsuji, Mariko; Yamaguchi, Megumi; Kitamura, Natsumi; Tanaka, Sachi; Nakamura, Yukinobu; Okitani, Akihiro
2016-11-01
The object of the present study was to reveal the action of inosine-5'-monophosphate (IMP) toward myofibrils in postmortem muscles. IMP solubilized isolated actomyosin within a narrow range of KCl concentration, 0.19-0.20 mol/L, because of the dissociation of actomyosin into actin and myosin, but it did not solubilize the proteins in myofibrils with 0.2 mol/L KCl. However, IMP could solubilize both proteins in myofibrils with 0.2 mol/L KCl in the presence of 1 m mol/L pyrophosphate or 1.0-3.3 m mol/L adenosine-5'-diphosphate (ADP). Thus, we presumed that pyrophosphate and ADP released thin filaments composed of actin, and thick filaments composed of myosin from restraints of myofibrils, and then both filaments were solubilized through the IMP-induced dissociation of actomyosin. Thus, we concluded that IMP is a candidate agent to resolve rigor mortis because of its ability to break the association between thick and thin filaments. © 2016 Japanese Society of Animal Science.
Liu, Jianmin; Li, Yuanyuan; Li, Dacheng
2012-01-01
In the centrosymmetric title coordination compound, [Er2{Fe(C5H5)(C6H4O2)}6(CH3OH)2(H2O)2]·2CH3OH, the two ErIII ions are bridged by two ferrocenecarboxylate anions as asymmetrically bridging ligands, leading to dimeric cores. The ErIII ion has a distorted dodecahedral coordination with six coordinating O atoms derived from the ferrocenecarboxylate ligands and two coordinated O atoms from one water molecule and one methanol molecule. The asymmetric unit comprises a half of the complex molecule and a methanol solvent molecule. Intramolecular O—H⋯O and C—H⋯O interactions occur. In the crystal, molecules are linked by intermolecular O—H⋯O hydrogen bonds and C—H⋯O as well as C—H⋯π interactions. PMID:22259358
Methanogenic degradation of acetone by an enrichment culture.
Platen, H; Schink, B
1987-01-01
An anaerobic enrichment culture degraded 1 mol of acetone to 2 mol of methane and 1 mol of carbon dioxide. Two microorganisms were involved in this process, a filament-forming rod similar to Methanothrix sp. and an unknown rod with round to slightly pointed ends. Both organisms formed aggregates up to 300 micron in diameter. No fluorescing bacteria were observed indicating that hydrogen or formate-utilizing methanogens are not involved in this process. Acetate was utilized in this culture by the Methanothrix sp. Inhibition of methanogenesis by bromoethanesulfonic acid or acetylene decreased the acetone degradation rate drastically and led to the formation of 2 mol acetate per mol of acetone. Streptomycin completely inhibited acetone degradation, and neither acetate nor methane was formed. 14CO2 was incorporated exclusively into the C-1 atom of acetate indicating that acetone is degraded via carboxylation to an acetoacetate residue. It is concluded that acetone is degraded by a coculture of an eubacterium and an acetate-utilizing methanogen and that acetate is the only intermediate transferred between both. The energetical problems of the eubacterium converting acetone to acetate are discussed.
Rodrigues, José B M; Sarantópoulos, Claire I G L; Bromberg, Renata; Andrade, Juliana C; Brunelli, Kleber; Miyagusku, Luciana; Marquezini, Miriam G; Yamada, Eunice A
2017-03-01
This study evaluates the potential of using non-irradiated barrier-shrink bags containing ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and ethylene ionomer in their structures to preserve vacuum-packaged fresh beef as an alternative to traditional gamma-ray cross-linked bags containing polyvinylidene chloride (PVDC). Boneless beef rib eye roll cuts were vacuum-packed in an industrial processing plant using EVOH 44% mol, EVOH 32% mol and a control PVDC barrier shrink bags. The cuts were evaluated during storage at 0.5°C. The EVOH films presented similar performance compared to control PVDC barrier shrink bags related to bacteria growth and purge loss. Packages with EVOH 32% mol film presented better performance than control bag with respect to the meat sensorial attributes, including fewer bubbles and better adhesion. EVOH 44% mol bags presented the highest rate of colour loss. The EVOH 32% mol non-irradiated and chlorine-free film is as effective for the preservation of fresh beef as traditional PVDC-irradiated shrink bags. Copyright © 2016 Elsevier Ltd. All rights reserved.
Human oocyte cryopreservation as an adjunct to IVF-embryo transfer cycles.
Boldt, Jeffrey; Cline, Donald; McLaughlin, David
2003-06-01
The purpose of this work was to develop methods for successful cryopreservation of human oocytes. Two cryopreservation procedures were used. Method 1 involved use of 1.5 mol/l propanediol (PrOH)-0.1 mol/l sucrose with medium containing sodium (Na) as cryoprotectant medium, seeding at -7 degrees C, and stepwise dilution of cryoprotectant post-thaw. Method 2 used Na-depleted media with 1.5 mol/l PrOH-0.2 mol/l sucrose for freezing, seeding at -6 degrees C, and use of high sucrose (0.5 and 0.2 mol/l) for cryoprotectant removal. The first method was used in seven patients, and gave poor (12.3%) survival results and no pregnancies. The second method was used in 15 patients (16 cycles), and yielded good survival and fertilization rates (74.4 and 59% respectively), with four pregnancies and five healthy infants born to 11 women receiving an embryo transfer. Using Na-depleted media along with other alterations in freezing and thawing procedures, human oocyte cryopreservation can provide excellent survival and pregnancy rates.
Macro-hydrogels versus nanoparticles by the controlled assembly of polysaccharides.
Costalat, M; Alcouffe, P; David, L; Delair, T
2015-12-10
The controlled assembly of oppositely charged chitosan (CS, Mw ∼ 33 × 10(3) to 600 × 10(3)g mol(-1)) and dextran sulfate (DS, Mw = 1.3 × 10(6)g mol(-1)) or heparin (HP, Mw = 1.8 × 10(4)g mol(-1)) led either to nanoparticles or macro-hydrogels, at room temperature. The control over the electrostatic attractive interactions was achieved using 2 mol L(-1) NaCl in the polyion solutions and subsequent dialysis to let the assembly occur. Macrohydrogels formed with an excess of polyanion. In the presence of an excess of polycation, colloidal gels were exclusively obtained. At salt concentrations lower than 1 mol L(-1), the spontaneous gelation provided macro-hydrogels, whatever the polyion in excess. Rheology measurements showed a similar elastic behaviour for CS-DS and CS-HP hydrogels, though CS-HP hydrogels appeared less cohesive. SAXS experiments revealed an aggregate morphology with internal and surface structure depending on the degree of acetylation (DA) of chitosan. Copyright © 2015 Elsevier Ltd. All rights reserved.
Calibrations between the variables of microbial TTI response and ground pork qualities.
Kim, Eunji; Choi, Dong Yeol; Kim, Hyun Chul; Kim, Keehyuk; Lee, Seung Ju
2013-10-01
A time-temperature indicator (TTI) based on a lactic acid bacterium, Weissella cibaria CIFP009, was applied to ground pork packaging. Calibration curves between TTI response and pork qualities were obtained from storage tests at 2°C, 10°C, and 13°C. The curves of the TTI vs. total cell number at different temperatures coincided to the greatest extent, indicating the highest representativeness of calibration, by showing the least coefficient of variance (CV=11%) of the quality variables at a given TTI response (titratable acidity) on the curves, followed by pH (23%), volatile basic nitrogen (VBN) (25%), and thiobarbituric acid-reactive substances (TBARS) (47%). Similarity of Arrhenius activation energy (Ea) could also reflect the representativeness of calibration. The total cell number (104.9 kJ/mol) was found to be the most similar to that of the TTI response (106.2 kJ/mol), followed by pH (113.6 kJ/mol), VBN (77.4 kJ/mol), and TBARS (55.0 kJ/mol). Copyright © 2013 Elsevier Ltd. All rights reserved.
Crystal structures of 1-hydroxy-4-propyloxy-9,10-anthraquinone and its acetyl derivative
Nakagawa, Hidemi; Kitamura, Chitoshi
2017-01-01
1-Hydroxy-4-propyloxy-9,10-anthraquinone, C17H14O4, (I), and its acetyl derivative, 4-acetyloxy-4-propyloxy-9,10-anthraquinone, C19H16O5, (II), were synthesized from the commercially available dye quinizarin. In both compounds, the anthraquinone frameworks are close to planarity. There is a large difference in the conformation of the propyloxy group; the molecule of (I) adopts a gauche conformation [O—C—C—C = −64.4 (2)°], although the molecule of (II) takes a trans-planar conformation (zigzag) [O—C—C—C = 176.1 (3)°]. In the molecule of (I), there is an intramolecular O—H⋯O hydrogen bond. In both crystals, the molecules are linked by C—H ⋯O hydrogen bonds. A difference in the molecular arrangements of (I) and (II) is found along the stacking directions. PMID:29250400
Qwele, K; Hugo, A; Oyedemi, S O; Moyo, B; Masika, P J; Muchenje, V
2013-03-01
The present study determined the chemical composition, fatty acid (FA) content and antioxidant capacity of meat from goats supplemented with Moringa oleifera leaves (MOL) or sunflower cake (SC) or grass hay (GH). The meat from goat supplemented with MOL had higher concentrations of total phenolic content (10.62±0.27 mg tannic acid equivalent E/g). The MOL significantly scavenged 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic-acid (ABTS) radical to 93.51±0.19% (93.51±0.19%) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical to 58.95±0.3% than other supplements. The antioxidative effect of MOL supplemented meat on catalase (CAT), reduced glutathione (GSH), superoxide dismutase (SOD) and lipid oxidation (LO) was significantly (P<0.05) higher than other meat from goat feed on grass hay or those supplemented with sunflower seed cake. The present study indicated that the anti-oxidative potential of MOL may play a role in improving meat quality (chemical composition, colour and lipid stability). Copyright © 2012 Elsevier Ltd. All rights reserved.
Li, Feng; Lin, Jin-qin; Liang, Yan-yan; Gan, Hua-yang; Zeng, Xiang-yun; Duan, Zhi-peng; Liang, Kai; Liu, Xing; Huo, Zhen-hai; Wu, Chang-hua
2014-07-15
Surface sediments from the coastal area of the Leizhou Peninsula in the South China Sea were collected and analyzed and the potential ecological risks in the area were assessed based on acid-volatile sulfide (AVS) model. The AVS levels are between 0.109 and 55.6 μmol g(-1), with the average at 4.45 μmol g(-1). The high AVS-concentration zones include the aquaculture areas of Liusha Bay and the densely populated areas of Zhanjiang Bay. The simultaneously extracted metals (SEM) range from 0.026 μmol g(-1) to 8.61 μmol g(-1), with the average at 0.843 μmol g(-1). Most of high SEM-concentration stations were located in ports or aquaculture zones. Most of the coastal surface sediments of the Leizhou Peninsula (90%) had no adverse biological effects according to the criterion proposed by USEPA (2005); while adverse effects were uncertain in some stations (8%); even in 2 stations (2%) adverse biological effects may be expected. Copyright © 2014 Elsevier Ltd. All rights reserved.
Regulation of flagellar assembly by glycogen synthase kinase 3 in Chlamydomonas reinhardtii.
Wilson, Nedra F; Lefebvre, Paul A
2004-10-01
Chlamydomonas reinhardtii controls flagellar assembly such that flagella are of an equal and predetermined length. Previous studies demonstrated that lithium, an inhibitor of glycogen synthase kinase 3 (GSK3), induced flagellar elongation, suggesting that a lithium-sensitive signal transduction pathway regulated flagellar length (S. Nakamura, H. Takino, and M. K. Kojima, Cell Struct. Funct. 12:369-374, 1987). Here, we demonstrate that lithium treatment depletes the pool of flagellar proteins from the cell body and that the heterotrimeric kinesin Fla10p accumulates in flagella. We identify GSK3 in Chlamydomonas and demonstrate that its kinase activity is inhibited by lithium in vitro. The tyrosine-phosphorylated, active form of GSK3 was enriched in flagella and GSK3 associated with the axoneme in a phosphorylation-dependent manner. The level of active GSK3 correlated with flagellar length; early during flagellar regeneration, active GSK3 increased over basal levels. This increase in active GSK3 was rapidly lost within 30 min of regeneration as the level of active GSK3 decreased relative to the predeflagellation level. Taken together, these results suggest a possible role for GSK3 in regulating the assembly and length of flagella.
von Twickel, Arndt; Büschges, Ansgar; Pasemann, Frank
2011-02-01
This article presents modular recurrent neural network controllers for single legs of a biomimetic six-legged robot equipped with standard DC motors. Following arguments of Ekeberg et al. (Arthropod Struct Dev 33:287-300, 2004), completely decentralized and sensori-driven neuro-controllers were derived from neuro-biological data of stick-insects. Parameters of the controllers were either hand-tuned or optimized by an evolutionary algorithm. Employing identical controller structures, qualitatively similar behaviors were achieved for robot and for stick insect simulations. For a wide range of perturbing conditions, as for instance changing ground height or up- and downhill walking, swing as well as stance control were shown to be robust. Behavioral adaptations, like varying locomotion speeds, could be achieved by changes in neural parameters as well as by a mechanical coupling to the environment. To a large extent the simulated walking behavior matched biological data. For example, this was the case for body support force profiles and swing trajectories under varying ground heights. The results suggest that the single-leg controllers are suitable as modules for hexapod controllers, and they might therefore bridge morphological- and behavioral-based approaches to stick insect locomotion control.
Schullcke, Benjamin; Gong, Bo; Krueger-Ziolek, Sabine; Soleimani, Manuchehr; Mueller-Lisse, Ullrich; Moeller, Knut
2016-05-16
Lung EIT is a functional imaging method that utilizes electrical currents to reconstruct images of conductivity changes inside the thorax. This technique is radiation free and applicable at the bedside, but lacks of spatial resolution compared to morphological imaging methods such as X-ray computed tomography (CT). In this article we describe an approach for EIT image reconstruction using morphologic information obtained from other structural imaging modalities. This leads to recon- structed images of lung ventilation that can easily be superimposed with structural CT or MRI images, which facilitates image interpretation. The approach is based on a Discrete Cosine Transformation (DCT) of an image of the considered transversal thorax slice. The use of DCT enables reduction of the dimensionality of the reconstruction and ensures that only conductivity changes of the lungs are reconstructed and displayed. The DCT based approach is well suited to fuse morphological image information with functional lung imaging at low computational costs. Results on simulated data indicate that this approach preserves the morphological structures of the lungs and avoids blurring of the solution. Images from patient measurements reveal the capabilities of the method and demonstrate benefits in possible applications.
Schullcke, Benjamin; Gong, Bo; Krueger-Ziolek, Sabine; Soleimani, Manuchehr; Mueller-Lisse, Ullrich; Moeller, Knut
2016-01-01
Lung EIT is a functional imaging method that utilizes electrical currents to reconstruct images of conductivity changes inside the thorax. This technique is radiation free and applicable at the bedside, but lacks of spatial resolution compared to morphological imaging methods such as X-ray computed tomography (CT). In this article we describe an approach for EIT image reconstruction using morphologic information obtained from other structural imaging modalities. This leads to recon- structed images of lung ventilation that can easily be superimposed with structural CT or MRI images, which facilitates image interpretation. The approach is based on a Discrete Cosine Transformation (DCT) of an image of the considered transversal thorax slice. The use of DCT enables reduction of the dimensionality of the reconstruction and ensures that only conductivity changes of the lungs are reconstructed and displayed. The DCT based approach is well suited to fuse morphological image information with functional lung imaging at low computational costs. Results on simulated data indicate that this approach preserves the morphological structures of the lungs and avoids blurring of the solution. Images from patient measurements reveal the capabilities of the method and demonstrate benefits in possible applications. PMID:27181695
Harnessing the Bethe free energy†
Bapst, Victor
2016-01-01
ABSTRACT A wide class of problems in combinatorics, computer science and physics can be described along the following lines. There are a large number of variables ranging over a finite domain that interact through constraints that each bind a few variables and either encourage or discourage certain value combinations. Examples include the k‐SAT problem or the Ising model. Such models naturally induce a Gibbs measure on the set of assignments, which is characterised by its partition function. The present paper deals with the partition function of problems where the interactions between variables and constraints are induced by a sparse random (hyper)graph. According to physics predictions, a generic recipe called the “replica symmetric cavity method” yields the correct value of the partition function if the underlying model enjoys certain properties [Krzkala et al., PNAS (2007) 10318–10323]. Guided by this conjecture, we prove general sufficient conditions for the success of the cavity method. The proofs are based on a “regularity lemma” for probability measures on sets of the form Ωn for a finite Ω and a large n that may be of independent interest. © 2016 Wiley Periodicals, Inc. Random Struct. Alg., 49, 694–741, 2016 PMID:28035178
NASA Astrophysics Data System (ADS)
Rao, Francesco; Caflisch, Amedeo
2004-03-01
Networks are everywhere. The conformation space of a 20-residue antiparallel beta-sheet peptide [1], sampled by molecular dynamics simulations, is mapped to a network. Conformations are nodes of the network, and the transitions between them are links. As previously found for the World-Wide Web as well as for social and biological networks , the conformation space contains highly connected hubs like the native state which is the most populated free energy basin. Furthermore, the network shows a hierarchical modularity [2] which is consistent with the funnel mechanism of folding [3] and is not observed for a random heteropolymer lacking a native state. Here we show that the conformation space network describes the free energy landscape without requiring projections into arbitrarily chosen reaction coordinates. The network analysis provides a basis for understanding the heterogeneity of the folding transition state and the existence of multiple pathways. [1] P. Ferrara and A. Caflisch, Folding simulations of a three-stranded antiparallel beta-sheet peptide, PNAS 97, 10780-10785 (2000). [2] Ravasz, E. and Barabási, A. L. Hierarchical organization in complex networks. Phys. Rev. E 67, 026112 (2003). [3] Dill, K. and Chan, H From Levinthal to pathways to funnels. Nature Struct. Biol. 4, 10-19 (1997)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Champion, Mark S; Dean, Robert A; Galambos, John D
The Proton Power Upgrade Project is underway at the Spallation Neutron Source at Oak Ridge National Labor-atory and will double the proton beam power capability from 1.4 MW to 2.8 MW to provide increased neutron intensity at the first target station and to support future operation of the second target station. This will be ac-complished by increasing the beam energy to 1.3 GeV and the beam current to 38 mA (average during the macropulse). Installation of 28 additional superconduct-ing cavities and their associated technical systems will provide for the energy increase. Increased beam loading throughout the accelerator will be accommodatedmore » primar-ily through the use of existing margin in the RF systems and the installation of 700 kW klystrons to power the new superconducting cavities. Upgrades of a few existing RF stations may also be needed. The injection and ex-traction regions of the accumulator ring will be upgraded, a ring to second target station tunnel stub will be con-structed, and a 2 MW target will be developed for the first target station. The project anticipates attainment of Criti-cal Decision 1 in 2017 to ratify the project conceptual design and cost range.« less
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.; Partridge, Harry; Scuseria, Gustavo E.
1992-01-01
The correlation contribution to the M-C binding energy for the MCH2(+) systems can exceed 100 kcal/mol. At the self-consistent field (SCF) level, these systems can be more than 50 kcal/mol above the fragment energies. In spite of the poor zeroth-order reference, the coupled cluster single and double excitation method with a perturbational estimate of triple excitations, CCSD(T), method is shown to provide an accurate description of these systems. The maximum difference between the CCSD(T) and internally contracted averaged coupled-pair functional binding energies is 1.5 kcal/mol for CrCH2(+), with the remaining systems agreeing to within 1.0 kcal/mol.
9-(3,4-Dimeth-oxy-phen-yl)-3,3,6,6-tetra-methyl-4,5,6,9-tetra-hydro-3H-xanthene-1,8(2H,7H)-dione.
Mehdi, Sayed Hasan; Sulaiman, Othman; Ghalib, Raza Murad; Yeap, Chin Sing; Fun, Hoong-Kun
2011-07-01
The asymmetric unit of the title xanthene compound, C(25)H(30)O(5), contains two mol-ecules in which the pyran ring and the dimeth-oxy-phenyl ring are nearly perpendicular to one another [dihedral angles = 86.81 (8) and 84.45 (9)°]. One of the meth-oxy groups in one mol-ecule is twisted away from the phenyl ring [C-O-C-C torsion angle = -103.40 (16)°]. The pyran ring adopts a boat conformation whereas the two fused cyclo-hexane rings adopt envelope conformations in both mol-ecules. In the crystal, mol-ecules are linked into a three-dimensional network by C-H⋯O hydrogen bonds.
Isolation of copper-binding proteins from activated sludge culture.
Fukushi, K; Kato, S; Antsuki, T; Omura, T
2001-01-01
Six copper-binding microbial proteins were isolated from activated sludge cultures grown on media containing copper at various concentrations. Molecular weights among isolated proteins were ranged from 1.3k to 1 74k dalton. Isolated proteins were compared for their copper binding capabilities. Proteins isolated from cultures grown in the presence of copper in the growth media exhibited higher copper binding capabilities than those isolated from the culture grown in the absence of copper. The highest metal uptake of 61.23 (mol copper/mol protein) was observed by a protein isolated from a culture grown with copper at a concentration of 0.25 mM. This isolated protein (CBP2) had a molecular weight of 24k dalton. Other protein exhibited copper binding capability of 4.8-32.5 (mol copper/mol protein).
Dopant occupancy and UV-VIS-NIR spectroscopy of Mg (0, 4, 5 and 6 mol.%):Dy:LiNbO3 crystal
NASA Astrophysics Data System (ADS)
Dai, Li; Liu, Chunrui; Han, Xianbo; Wang, Luping; Tan, Chao; Yan, Zhehua; Xu, Yuheng
2017-09-01
A series of Dy:LiNbO3 crystals with x mol.% Mg2+ ions (x =0, 4, 5 and 6 mol.%) were grown by the Czochralski method. The effective segregation coefficient of Mg2+ and Dy3+ ions was studied by the inductively coupled plasma-atomic emission spectrometry (ICP-AES). UV-VIS-NIR absorption spectra and Judd-Ofelt theory were used to investigate their spectroscopic properties. J-O intensity parameters (Ω2 = 7.53 × 10-20cm2, Ω4 = 6.98 × 10-20cm2, and Ω6 = 3.09 × 10-20cm2) and larger spectroscopic quality factor (X = 2.26) for Mg:(6 mol.%)Dy:LiNbO3 crystals were obtained.
G3X-K theory: A composite theoretical method for thermochemical kinetics
NASA Astrophysics Data System (ADS)
da Silva, Gabriel
2013-02-01
A composite theoretical method for accurate thermochemical kinetics, G3X-K, is described. This method is accurate to around 0.5 kcal mol-1 for barrier heights and 0.8 kcal mol-1 for enthalpies of formation. G3X-K is a modification of G3SX theory using the M06-2X density functional for structures and zero-point energies and parameterized for a test set of 223 heats of formation and 23 barrier heights. A reduced perturbation-order variant, G3X(MP3)-K, is also developed, providing around 0.7 kcal mol-1 accuracy for barrier heights and 0.9 kcal mol-1 accuracy for enthalpies, at reduced computational cost. Some opportunities to further improve Gn composite methods are identified and briefly discussed.
Cork, Douglas J.; Garunas, Ruta; Sajjad, Ashfaq
1983-01-01
Chlorobium limicola forma thiosulfatophilum (ATCC 17092) was grown in a 1-liter continuously stirred tank reactor (800-ml liquid volume) at pH 6.8, 30°C, saturated light intensity, and a gas flow rate of 23.6 ml/min from a gas cylinder blend consisting of 3.9 mol% H2S, 9.2 mol% CO2, 86.4 mol% N2, and 0.5 mol% H2. This is the first demonstration of photoautotrophic growth of a Chlorobium sp. on a continuous inorganic gas feed. A significant potential exists for applying this photoautotrophic process to desulfurization and CO2 fixation of gases containing acidic components (H2S and CO2). PMID:16346255
1,2-Diiodo-4,5-dimethylbenzene
Hathaway, Bruce A.; Kilgore, Uriah J.; Bond, Marcus R.
2009-01-01
The structure of the title compound, C8H8I2, conforms closely to the mm2 symmetry expected for the free molecule and is the first reported structure of a diiododimethylbenzene. Repulsion by neighboring I atoms and the neighboring methyl groups opposite to them results in a slight elongation of the molecule along the approximate twofold rotation axis that bisects the ring between the two I atoms. In the extended structure, the molecules form inversion-related pairs which are organized in approximately hexagonal close-packed layers and the layers then stacked so that molecules in neighboring layers abut head-to-tail in a manner that optimizes dipole–dipole interactions. PMID:21583089
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.
1994-01-01
Modified coupled-pair functional (MCPF) calculations and coupled cluster singles and doubles calculations, which include a perturbational estimate of the connected triples [CCSD(T)], yield a bent structure for CuCO, thus, supporting the prediction of a nonlinear structure based on density functional (DF) calculations. Our best estimate for the binding energy is 4.9 +/- 1.4 kcal/mol; this is in better agreement with experiment (6.0 +/- 1.2 kcal/mol) than the DF approach which yields a value (19.6 kcal/mol) significantly larger than experiment.
Hancke, Kasper; Dalsgaard, Tage; Sejr, Mikael Kristian; Markager, Stiig; Glud, Ronnie Nøhr
2015-01-01
Accurate quantification of pelagic primary production is essential for quantifying the marine carbon turnover and the energy supply to the food web. Knowing the electron requirement (Κ) for carbon (C) fixation (Κ C) and oxygen (O2) production (Κ O2), variable fluorescence has the potential to quantify primary production in microalgae, and hereby increasing spatial and temporal resolution of measurements compared to traditional methods. Here we quantify Κ C and Κ O2 through measures of Pulse Amplitude Modulated (PAM) fluorometry, C fixation and O2 production in an Arctic fjord (Godthåbsfjorden, W Greenland). Through short- (2h) and long-term (24h) experiments, rates of electron transfer (ETRPSII), C fixation and/or O2 production were quantified and compared. Absolute rates of ETR were derived by accounting for Photosystem II light absorption and spectral light composition. Two-hour incubations revealed a linear relationship between ETRPSII and gross 14C fixation (R2 = 0.81) during light-limited photosynthesis, giving a Κ C of 7.6 ± 0.6 (mean ± S.E.) mol é (mol C)−1. Diel net rates also demonstrated a linear relationship between ETRPSII and C fixation giving a Κ C of 11.2 ± 1.3 mol é (mol C)−1 (R2 = 0.86). For net O2 production the electron requirement was lower than for net C fixation giving 6.5 ± 0.9 mol é (mol O2)−1 (R2 = 0.94). This, however, still is an electron requirement 1.6 times higher than the theoretical minimum for O2 production [i.e. 4 mol é (mol O2)−1]. The discrepancy is explained by respiratory activity and non-photochemical electron requirements and the variability is discussed. In conclusion, the bio-optical method and derived electron requirement support conversion of ETR to units of C or O2, paving the road for improved spatial and temporal resolution of primary production estimates. PMID:26218096
Klien, Henrik; Seichter, Wilhelm; Weber, Edwin
2015-01-01
In the title solvate, C44H26Cl4O2·3C6H15N, the asymmetric part of the unit cell comprises two halves of the diol molecules, 2,2′′-bis(2,7-dichloro-9-hydroxy-9H-fluoren-9-yl)-1,1′:4′,1′′-terphenyl, and three molecules of triethylamine, i. e. the diol molecules are located on crystallographic symmetry centres. Two of the solvent molecules are disordered over two positions [occupancy ratios of 0.567 (3):0.433 (3) and 0.503 (3):0.497 (3)]. In the diol molecules, the outer rings of the 1,1′:4′,1′′-terphenyl elements are twisted with reference to their central arene ring and the mean planes of the fluorenyl moieties are inclined with respect to the terphenyl ring to which they are connected, the latter making dihedral angles of 82.05 (8) and 82.28 (8)°. The presence of two 9-fluoren-9-ol units attached at positions 2 and 2′′ of the terphenyl moiety induces a ‘folded’ geometry which is stabilized by intramolecular C—H⋯O hydrogen bonds and π–π stacking interactions, the latter formed between the fluorenyl units and the central ring of the terphenyl unit [centroid–centroid distances = 3.559 (1) and 3.562 (1) Å]. The crystal is composed of 1:2 complex units, in which the solvent molecules are associated with the diol molecules via O—H⋯N hydrogen bonds, while the remaining solvent molecule is linked to the host by a C—H⋯N hydrogen bond. The given pattern of intermolecular interactions results in formation of chain structures extending along [010]. PMID:26870400