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1

Programing the formation of DNA and PNA quadruplexes by pi-pi-stacking interactions.  

PubMed

Guanine (G) rich G(4)T(4)G(4) DNA and homologous PNA strands tend to form antiparallel dimeric quadruplexes. In contrast, the same DNA strands carrying planar aromatic 5'-residues preferentially form parallel DNA quadruplex. Conformation and composition of the DNA quadruplexes can be programed by pi-pi-stacking interaction exerted by the 5'-residues. PMID:20177616

Saha, Sourav; Cai, Jianfeng; Eiler, Daniel; Hamilton, Andrew D

2010-03-14

2

Hydrogen bond, pi-pi stacking, and van der Waals interactions investigated with density functional theory  

NASA Astrophysics Data System (ADS)

Weak bonds such as hydrogen bond, pi-pi stacking and van der Waals interaction are much weaker in the strength but play a more important role for the existence of various lives. For example, they are the major intermolecular interactions in the liquid and solid structure of water and determine the 3 dimensional structure of protein and DNA, which are the crucial organic molecules in lives. As a result, studying these weak bonds can lead to the better understanding of fundamental knowledge of lives. Kohn-Sham (K-S) Density Functional Theory (DFT) is an accurate and effect way to investigate the fundamental properties for many-body systems, in which, only the exchange-correlation energy as a functional of electron density need to be approximated. However, weak interaction system is still a challenge problem for KS-DFT. In this dissertation work, several standard density functionals are used to study these weak interactions in the solid state structure ice as long as nucleic bases molecules in the biologic system. It is found that the hydrogen bond can be well described by most semilocal functionals: the mismatch problem of ice Ih and AgI for GGA functional can be solved by using the higher level meta-GGA functionals and the binding length and energy between nucleic bases in DNA can be well described. However, the more accurate dispersion correction is strongly needed for van der Waals interactions and pi stacking for super-high pressure ice phases and large size biologic molecules, where van der Waals interaction takes major role. Finally, the basic structural properties of various phases of ice and DNA can be understood based on the investigation with appropriate functionals.

Fang, Yuan

3

Homochiral, helical metal-organic framework structures organized by strong, non-covalent pi-pi stacking interactions.  

PubMed

A new trifunctional ligand, L(ala), containing a carboxylate donor group, a homochiral center derived from L-alanine and a strong pi-pi stacking, 1,8-naphthalimide synthon, has been used to prepare the copper(II) complex [Cu(L(ala))2(4,4'-bipy)(H2O)2].4.25H2O that has a homochiral, helical, supramolecular metal-organic framework 3-D structure, organized in one dimension solely by strong non-covalent forces. PMID:19826674

Reger, Daniel L; Horger, Jacob; Smith, Mark D; Long, Gary J

2009-11-01

4

Hydrogen-bonding and pi-pi stacking interactions in aquachloridobis(1,10-phenanthroline)cobalt(II) chloride dichloridobis(1,10-phenanthroline)cobalt(II) hexahydrate.  

PubMed

The title compound, [CoCl(C(12)H(8)N(2))(2)(H(2)O)]Cl.[CoCl(2)(C(12)H(8)N(2))(2)].6H(2)O, is the first example of a new 1:1 cocrystal of the octahedral [CoCl(2)(phen)(2)] and [CoCl(phen)(2)(H(2)O)](+).Cl(-) complexes (phen is 1,10-phenanthroline). The latter form heterochiral dimers held by strong pi-pi stacking interactions via their phenathroline ligands, which confirms that pi stacking is an important and reliable synthon in supramolecular design. In addition, the crystal structure is networked by H(2)O...H(2)O, H(2)O...Cl(-) and H(2)O...Cl hydrogen bonds, which interconnect the different units of the cobalt complexes. PMID:18252993

Rubin-Preminger, Janice M; Kozlov, Leonid; Goldberg, Israel

2008-02-01

5

Hydrogen-bonding versus pi-pi stacking interactions in dipyrido[f,h]quinoxaline-6,7-dicarbonitrile and 6,7-dicyanodipyrido[f,h]quinoxalin-1-ium chloride dihydrate.  

PubMed

The solvent-free title compound, C(16)H(6)N(6), is an aromatic derivative of phenanthroline with an extended pi system. It exhibits a remarkable pi-pi columnar stacking in the crystal structure, with interplanar distances of 3.229 (3) and 3.380 (3) A, the shorter spacing being between the two molecules within the asymmetric unit. Adjacent units along the stacked arrays are rotated in-plane with respect to one another by approximately 120 degrees . The hydrochloride derivative, C(16)H(7)N(6)(+).Cl(-).2H(2)O, in which one of the phenanthroline N atoms has been protonated, crystallized as a dihydrate. The supramolecular organization in this compound is characterized by continuous hydrogen bonding between the component species, yielding two-dimensional hydrogen-bonded networks. This study demonstrates the high significance of the pi-pi stacking interactions in the solvent-free aromatic system and how they can be undermined by introducing hydrogen-bonding capacity into the ligand. PMID:18758019

Kozlov, Leonid; Goldberg, Israel

2008-09-01

6

Nanofibers formed through pi...pi stacking of the complexes of glucosyl-C2-salicyl-imine and phenylalanine: characterization by microscopy, modeling by molecular mechanics, and interaction by alpha-helical and beta-sheet proteins.  

PubMed

This paper deals with the self-assembly of the 1:1 complex of two different amphiphiles, namely, a glucosyl-salicyl-imino conjugate (L) and phenylalanine (Phe), forming nanofibers over a period of time through pi...pi interactions. Significant enhancement observed in the fluorescence intensity of L at approximately 423 nm band and the significant decrease observed in the absorbance of the approximately 215 nm band are some characteristics of this self-assembly. Matrix-assisted laser desorption ionization/time of flight titration carried out at different time intervals supports the formation of higher aggregates. Atomic force microscopy (AFM), transmission electron microscopy, and scanning electron miscroscopy results showed the formation of nanofibers for the solutions of L with phenylalanine. In dynamic light scattering measurements, the distribution of the particles extends to a higher diameter range over time, indicating a slow kinetic process of assembly. Similar spectral and microscopy studies carried out with the control molecules support the role of the amino acid moiety over the simple -COOH moiety as well as the side chain phenyl moiety in association with the amino acid, in the formation of these fibers. All these observations support the presence of pi...pi interactions between the initially formed 1:1 complexes leading to the fiber formation. The aggregation of 1:1 complexes leading to fibers followed by the formation of bundles has been modeled by molecular mechanics studies. Thus the fiber formation with L is limited to phenylalanine and not to any other naturally occurring amino acid and hence a polymer composed of two different biocompatible amphiphiles. AFM studies carried out between the fiber forming mixture and proteins resulted in the observation that only BSA selectively adheres to the fiber among the three alpha-helical and two beta-sheet proteins studied and hence may be of use in some medical applications. PMID:20521836

Acharya, Amitabha; Ramanujam, Balaji; Mitra, Atanu; Rao, Chebrolu P

2010-07-27

7

pi-pi Stacking of curved carbon networks: The corannulene dimer  

NASA Astrophysics Data System (ADS)

Dimers of corannulene, a curved, saucer shaped molecule, were studied by theoretical calculations using second order Møller-Plesset perturbation theory and a large polarized triple zeta basis set. Three dimer motifs were investigated: the "native" dimer is the concave-convex stacking of two monomers with the geometries of both monomers conserved; the ldquoplanarrdquo motif with both monomers forced to be planar; and the ldquoC60-likerdquo dimer where the outer monomer has the native geometry while the inner one has the curvature of buckminsterfullerene C60. Both staggered and eclipsed conformations of the dimers were investigated. Our calculations show that the binding energy of the native concave-convex corannulene dimer is quite substantial (17.2 kcal/mole at the ldquobestrdquo SCS-MP2/cc-pvtz level of theory) with an equilibrium distance of about 3.64 Å. Surprisingly, there are only minor differences in both binding energies and equilibrium distances between the three different dimer motifs. This suggests that the curvature of the conjugated carbon networks does not disable their ability to form pi-pi stacked assemblies similar to the planar systems. However, in contrast to the planar systems, at least part of the binding energies in the stacked curved systems can be attributed to attractive electrostatic dipole-dipole contributions since buckybowls exhibit significant dipole moments. For the ldquoplanarrdquo dimer, a staggered arrangement of the two monomers is preferred, while eclipsed conformations are the most stable for all curved dimers. For all systems, the basis set superposition errors are large (ca. 7 kcal/mol) at the equilibrium distance even with our largest basis sets.

Sygula, Andrzej; Saebø, Svein

8

Jet-like structure in the reaction gammap-->pi+pi-pi+pi-pi+pi-p  

Microsoft Academic Search

We report on diffractive production of 6pi systems with a continuum of masses from 2 to 5 GeV\\/c2 in the reaction gammap-->pi+pi-pi+pi-pi+pi-p. The event structure is compared in detail with Monte Carlo studies of pT limited phase space, and with the jets observed in hadronic systems produced by electron-positron annihilation. Strong similarities are found. For this jet-like structure of the

D. Aston; M. Atkinson; R. Bailey; A. H. Ball; B. Bouquet; G. R. Brookes; J. Bröring; P. J. Bussey; D. Clarke; A. B. Clegg; B. D'Almagne; G. de Rosny; B. Diekmann; A. Donnachie; M. Draper; B. Drevillon; I. P. Duerdoth; J.-P. Dufey; R. J. Ellison; D. Ezra; P. Feller; A. Ferrer; P. J. Flynn; F. Friese; W. Galbraith; R. George; S. D. M. Gill; M. Goldberg; S. Goodman; W. Graves; B. Grossetête; P. G. Hampson; K. Heinloth; R. E. Hughes-Jones; J. S. Hutton; M. Ibbotson; M. Jung; S. Katsanevas; M. A. R. Kemp; F. Kovacs; B. R. Kumar; G. D. Lafferty; J.-M. Lévy; V. Liebenau; J. Litt; D. Mercer; J. V. Morris; K. Müller; D. Newton; E. Paul; P. Petroff; Y. Pons; C. Raine; F. Richard; R. Richter; J. H. C. Roberts; P. Roudeau; A. Rougé; M. Rumpf; M. Sené; I. O. Skillicorn; J. C. Sleeman; K. M. Smith; C. Steinhauer; K. M. Storr; R. J. Thompson; D. Treille; Ch. de La Vaissière; H. Videau; I. Videau; A. P. Waite; A. Wijangco; W. Wojcik; J.-P. Wuthrick; T. P. Yiou

1980-01-01

9

Hard spectator interactions in B to pi pi at order alpha_s^2  

Microsoft Academic Search

In the present thesis I discuss the hard spectator interaction amplitude in $B\\\\to\\\\pi\\\\pi$ at NLO i.e. at $\\\\mathcal{O}(\\\\alpha_s^2)$. This special part of the amplitude, whose LO starts at $\\\\mathcal{O}(\\\\alpha_s)$, is defined in the framework of QCD factorization. QCD factorization allows to separate the short- and the long-distance physics in leading power in an expansion in $\\\\lqcd\\/m_b$, where the short-distance physics

Volker Pilipp

2007-01-01

10

Effects of [pi]-[pi] interactions on molecular structure and resonance Raman spectra of crystalline copper(II) octaethylporphyrin  

SciTech Connect

Single-crystal resonance Raman measurements were performed on two crystalline phases of copper(II) octaethylporphyrin (CuOEP): triclinic A and triclinic B forms. These are compared to previously acquired resonance Raman data on the triclinic A and triclinic B phases of nickel(II) octaethylporphyrin (NiOEP). The difference in crystal packing between the triclinic A and B structures allows for more extensive [pi]-[pi] interactions in the B form than in the A form. Differences in the single-crystal Raman spectra of the triclinic A and B forms of both Cu- and NiOEP are attributed to these [pi]-[pi] interactions. Specifically, the Raman core-size marker lines, [nu][sub 3], [nu][sub 2], and [nu][sub 10], and the oxidation-state marker line, [nu][sub 4], are affected by the different packing interactions in the two crystals, and the same Raman shifting patterns between the triclinic A and B phases are observed for both Cu- and NiOEP. The metal centers exert a slight influence over the packing-induced frequency shifts in the Raman modes. Spectral results on the CuOEP crystals are also compared to solution Raman data on [pi]-[pi] aggregated and monomeric copper(II) uroporphyrin (CuUroP). Similar to the A and B forms of NiOEP, the CuOEP triclinic A and B crystalline phases mimic the monomer and salt-induced aggregate of CuUroP in solution, as evidenced by similar magnitude upshifts in the Raman modes upon aggregation. A comparison of the structure calculated using molecular mechanics and the structure obtained from X-ray diffraction gives some insight into the effect that [pi]-[pi] interactions have on the structure of CuOEP in the triclinic B crystal.

Sparks, L.D.; Shelnutt, J.A. (Sandia National Labs., Albuquerque, NM (United States) Univ. of New Mexico, Albuquerque (United States)); Scheidt, W.R. (Univ. of Notre Dame, IN (United States))

1992-05-27

11

Effects of [pi]-[pi] interactions on molecular structure and resonance Raman spectra of crystalline copper(II) octaethylporphyrin  

Microsoft Academic Search

Single-crystal resonance Raman measurements were performed on two crystalline phases of copper(II) octaethylporphyrin (CuOEP): triclinic A and triclinic B forms. These are compared to previously acquired resonance Raman data on the triclinic A and triclinic B phases of nickel(II) octaethylporphyrin (NiOEP). The difference in crystal packing between the triclinic A and B structures allows for more extensive [pi]-[pi] interactions in

L. D. Sparks; J. A. Shelnutt; W. R. Scheidt

1992-01-01

12

Functional organotrimethoxysilane derivative with strong intermolecular pi-pi interaction: one-pot grafting reaction on oxidized silicon substrates.  

PubMed

Although the fabrication of self-assembled monolayers (SAMs) on an oxidized silicon substrate with special functionality is an important topic for various applications, it is still very difficult to obtain a densely grafted monolayer. With a newly synthesized organotrimethoxysilane containing a 1-cyano-1,2-bisbiphenyl-ethylene (CNMBE) moiety which provides a strong pi-pi intermolecular interaction, an SAM of well-ordered structure is readily obtained by a one-pot grafting reaction under mild conditions. The aggregation process of the CNMBE moiety, which induced a close packing of organosilane on the substrate, was visually monitored by the fluorescence of the monolayer grafted on quartz. PMID:16893203

Nam, Haehyun; Granier, Michel; Boury, Bruno; Park, Soo Young

2006-08-15

13

Spectroscopic characterization of triple-decker lanthanide porphyrin sandwich complexes. Effects of strong. pi. pi. interactions in extended assemblies  

SciTech Connect

Electrochemical, optical absorption, near-infrared, infrared, resonance Raman, and electron paramagnetic resonance data are reported for several neutral and singly oxidized triple-decker lanthanide porphyrin sandwich complexes Ln{sub 2}(OEP){sub 3} (Ln = La(III), Ce(III), Eu(III); OEP = octaethylporphyrin). The data indicate that there are strong {pi}{pi} interactions between the porphyrin macrocycles in all of the complexes. As a consequence, the hole in the porphyrin {pi} system of the Ln{sub 2}(OEP){sub 3}{sup +} systems is delocalized over all three rings on the vibrational and electronic time scales. The singly oxidized complexes exhibit a characteristic electronic absorption band at very low energies (ca. 2200 nm). This absorption arises as a direct consequence of the strong {pi}{pi} interactions between the rings. A molecular orbital scheme is proposed that accounts for this low-energy feature as well as a number of other properties of the triple-decker sandwich complexes.

Duchowski, J.K.; Bocian, D.F. (Carnegie-Mellon Univ., Pittsburgh, PA (USA))

1990-11-21

14

Usefulness of pi...pi aromatic interactions in the selective separation and analysis of imidazolium and pyridinium ionic liquid cations.  

PubMed

Current research indicates that replacing organic solvents with room-temperature ionic liquids may lead to remarkable improvements in well-known processes. Ionic liquids have already been utilized as alternative solvents in organic synthesis and catalysis, and also in electrochemistry and in separation sciences. Their wide applicability will soon result in their production on an industrial scale. Therefore, analytical methods applicable to various matrices for product control and environmental monitoring will be very much in demand. In this study, the usefulness of pi...pi interactions between alkylimidazolium and pyridinium cations and the aromatic pi...pi active moiety of the stationary phase was investigated for the selective separation and analysis of some ionic liquids. With phenyl-bonded phases, very good separations of the cations were achieved. Special attention was paid to the short-chain hydrophilic entities, known to be poorly separated on conventional reversed-phase columns. Further, the nature of the interactions occurring in the system under study was investigated by varying the content of methanol/acetonitrile used as organic modifiers in the mobile phases. The analytical method developed here is simple and reproducible, and its quantitative analytical performance was excellent. The paper also discusses the applicability of the method for monitoring degraded cations of 1-butyl-3-methylimidazolium salts obtained in the Fenton process. PMID:16847625

Stepnowski, P; Nichthauser, J; Mrozik, W; Buszewski, B

2006-08-01

15

Pi-pi interaction between aromatic ring and copper-coordinated His81 imidazole regulates the blue copper active-site structure.  

PubMed

Noncovalent weak interactions play important roles in biological systems. In particular, such interactions in the second coordination shell of metal ions in proteins may modulate the structure and reactivity of the metal ion site in functionally significant ways. Recently, pi-pi interactions between metal ion coordinated histidine imidazoles and aromatic amino acids have been recognized as potentially important contributors to the properties of metal ion sites. In this paper we demonstrate that in pseudoazurin (a blue copper protein) the pi-pi interaction between a coordinated histidine imidazole ring and the side chains of aromatic amino acids in the second coordination sphere, significantly influences the properties of the blue copper site. Electronic absorption and electron paramagnetic resonance spectra indicate that the blue copper electronic structure is perturbed, as is the redox potential, by the introduction of a second coordination shell pi-pi interaction. We suggest that the pi-pi interaction with the metal ion coordinated histidine imidazole ring modulates the electron delocalization in the active site, and that such interactions may be functionally important in refining the reactivity of blue copper sites. PMID:17031705

Abdelhamid, Rehab F; Obara, Yuji; Uchida, Yoshiko; Kohzuma, Takamitsu; Dooley, David M; Brown, Doreen E; Hori, Hiroshi

2007-02-01

16

Assembly of a two-dimensional layer structure with 1,4-bis(1H-benzimidazol-1-ylmethyl)benzene dihydrate via hydrogen bonds and pi-pi interactions.  

PubMed

In the title compound, C(22)H(18)N(4).2H(2)O, the organic fragment lies across a centre of inversion in the P2(1)/n space group. The water molecules form C(2)-type hydrogen-bonded chains which are linked to the 1,4-bis(1H-benzimidazol-1-ylmethyl)benzene molecules through O-H...N hydrogen bonds, forming sheets reinforced by pi-pi stacking interactions between the aromatic rings within the layers. PMID:18322340

Wu, Chuan-Mei; Liang, Bing

2008-03-01

17

Efficient photoinduced electron transfer in a porphyrin tripod-fullerene supramolecular complex via pi-pi interactions in nonpolar media.  

PubMed

A novel porphyrin tripod (TPZn(3)) was synthesized via "click chemistry". Three porphyrin moieties of TPZn(3) are geometrically close and linked by a flexible linker. The electron-transfer oxidation of TPZn(3) results in intramolecular pi-dimer formation between porphyrin moieties as indicated by electrochemical, vis-NIR, and ESR measurements. The cyclic voltammogram of TPZn(3) exhibited stepwise one-electron oxidation processes of three porphyrin moieties in the range from 0.58 to 0.73 V (vs SCE in CH(2)Cl(2)). When TPZn(3) was oxidized by tris(2,2'-bipyridyl)-ruthenium(III) ([Ru(bpy)(3)](3+)), the oxidized species (TPZn(3))(n+) (0 < n pi-pi interactions as well as the coordination bond between Zn(2+) and the pyridine moiety. The formation of a 1:1 supramolecular complex of TPZn(3) with PyC(60) (TPZn(3)-PyC(60)) was indicated in the UV-vis and (1)H NMR spectra in nonpolar solvents. The association constant of TPZn(3) with PyC(60) (1.1 x 10(5) M(-1) in toluene) is much larger as compared with those of the corresponding monomer (MPZn) and dimer porphyrin (DPZn(2)). The dynamics of photoinduced electron transfer from the singlet excited state of TPZn(3) to PyC(60) was examined by laser flash photolysis measurements. The efficient intracomplex photoinduced electron transfer in TPZn(3)-PyC(60) occurred in nonpolar solvents, resulting from the pi-pi interactions between the porphyrin and fullerene moieties, together with intramolecular pi-bond formation between the porphyrin radical cation and the neutral porphyrin in TPZn(3)(*+). PMID:20201539

Takai, Atsuro; Chkounda, Mohammed; Eggenspiller, Antoine; Gros, Claude P; Lachkar, Mohammed; Barbe, Jean-Michel; Fukuzumi, Shunichi

2010-03-31

18

Unsymmetrical diimine chelation to M(II) (M=Zn, Cd, Pd): atropisomerism, pi-pi stacking and photoluminescence.  

PubMed

Three types of atropisomeric unsymmetrical diimine complexes, tetrahedral (L(R)(?))MX(2) (M = Zn, Cd; X = Cl, Br; R = Me, CMe(3), OH, OMe, Cl; 1a-k, type-I), tetrahedral (L(Me2)(?))ZnBr(2) (2, type-II) and square planar (L(OH)(?))PdCl(2) (3, type-III) with different photoluminescence properties, have been reported (L(R)(?) = (E)-4-R-N-(pyridine-2-ylmethylene)aniline; ? = dihedral angle between the diimine unit including the pyridine ring and the phenyl ring planes). In crystals, ? = 0° for type-I, 90° for type-II and 63° for type-III atropisomers have been confirmed by single crystal X-ray structure determinations of 1c, 1e, 2 and 3·H(2)O isomers. Optimizations of geometries in methanol have established ? = 28-32° for type-I, 90.83° for type-II and 43.44° for type-III isomers. In solids, type-I atropisomers with ? = 0, behave as conjugated 14?e systems facilitating ?-? stacking and are brightly luminescent at room temperature while type-II and type-III isomers in solid and type-I isomers in solutions are more like non-conjugated 8?e + 6?e systems and non-emissive. Frozen glasses of acetonitrile, methanol and dichloromethane-toluene mixture at 77 K of type-I isomers are emissive and display structured excitation and emission spectra for R = Me, CMe(3), OMe species. Excitation and emission maxima of frozen glasses (?(ex) = 320-380 nm; ?(em) = 440-485 nm) are red shifted in the solid (?(ex) = 390-455 nm; ?(em) = 470-550 nm). TD-DFT calculations on 1b, 1d, 1f and stacked (1b)(2) isomers and luminescence lifetime measurements have elucidated that an excited (1)ILCT state has been the origin of emission of the type-I isomers and delocalizations of the photoactive ?(diimine) and ?(diimine)(*) orbitals of the L(R)(?) over the stacked layers shift the ?(ext) and ?(em) of solids to lower energies than those in frozen glasses. The trends of diimine ligand based electron transfer events of the complexes in DMF have been investigated by cyclic voltammetry at 298 K. PMID:21681332

Saha Roy, Amit; Saha, Pinaki; Mitra, Partha; Maity, Shyam Sundar; Ghosh, Sanjib; Ghosh, Prasanta

2011-07-28

19

Hard spectator interactions in B to pi pi at order alpha_s^2  

NASA Astrophysics Data System (ADS)

In the present thesis I discuss the hard spectator interaction amplitude in Bto?? at NLO i.e. at {O}(?_s^2). This special part of the amplitude, whose LO starts at {O}(?_s), is defined in the framework of QCD factorization. QCD factorization allows to separate the short- and the long-distance physics in leading power in an expansion in `cd/m_b, where the short-distance physics can be calculated in a perturbative expansion in ?_s. Compared to other parts of the amplitude hard spectator interactions are formally enhanced by the hard collinear scale sqrt{`cd m_b}, which occurs next to the m_b-scale and leads to an enhancement of ?_s. From a technical point of view the main challenges of this calculation are due to the fact that we have to deal with Feynman integrals that come with up to five external legs and with three independent ratios of scales. These Feynman integrals have to be expanded in powers of `cd/m_b. I will discuss integration by parts identities to reduce the number of master integrals and differential equations techniques to get their power expansions. A concrete implementation of integration by parts identities in a computer algebra system is given in the appendix. Finally I discuss numerical issues like scale dependence of the amplitudes and branching ratios. It will turn out that the NLO contributions of the hard spectator interactions are important but small enough for perturbation theory to be valid

Pilipp, Volker

2007-09-01

20

Triplet excimer formation in platinum-based phosphors: a theoretical study of the roles of Pt-Pt bimetallic interactions and interligand pi-pi interactions.  

PubMed

We have used density functional theory (DFT) and time-dependent DFT to investigate the geometric and electronic structure and the optical properties of the phosphorescent platinum compounds: Pt(II) (2-(4',6'-difluorophenyl)pyridinato-N,C(2)')(2,4-pentanedionato-O,O) (FPt1) and Pt(II) (2-(4',6'-difluorophenyl)pyridinato-N,C(2)')(1,3-propanedionato-O,O) (FPt0). We first examined isolated compounds (monomers) and evaluated their photophysical properties at the ground-state and lowest triplet excited-state (T(1)) geometries; the characteristics of the S(0) --> T(1) transitions are nearly identical in both compounds. Dimers of FPt0 and of FPt1 were then studied in order to shed light, at least qualitatively, on the respective role of Pt-Pt bimetallic interactions and interligand pi-pi interactions in the formation of excimer structures. While the Pt-Pt interactions are critical for excimer formation, the interligand pi-pi interactions also play a significant role in determining the optimal excimer geometry and the magnitude of the phosphorescence energy lowering in going from the monomer to the aggregated dimer. The distorted cofacial-type excimer structures found for FPt1, with a Pt-Pt distance around 2.9 A and interligand distances around 3.5-3.8 A, lead to phosphorescence energy lowerings with respect to the monomer on the order of 0.7-0.96 eV, in very good agreement with experiment. PMID:19722650

Kim, Dongwook; Brédas, Jean-Luc

2009-08-19

21

Dipole interaction model predicted pi-pi* circular dichroism of cyclo(L-Pro)3 using structures created by semi-empirical, ab initio, and molecular mechanics methods.  

PubMed

Cyclo(l-Pro)3 (CP3) is a synthetic peptide created to model cis and torsionally strained peptide bonds that also exhibits a strong distinctive UV circular dichroic (CD) spectrum. Circular dichroic spectra were computed for the amide pi-pi* transition using the dipole interaction model for various conformations of the peptide. Conformations of CP3 were created initially from crystal data, and followed by energy minimizations via molecular mechanics using the cvff force field; the effects of additional geometric optimizations by semi-empirical and ab initio quantum mechanics were investigated. The CD spectra for each conformation were calculated using a variety of different parameters, and each result was compared with the published experimental spectrum [Deber, C.M., Scatturin, A., Vaidya, V.M. & Blout, E.R. (1970) Small cyclic proline peptides: UV absorption and CD. In: Peptides: Chemistry and Biochemistry, Proceedings of the First American Peptide Symposium (Weinstein, B., ed.), Marcel Dekker, New York pp. 163-173]. Herein, two distinct conformations, a C3 symmetric and an asymmetric form, gave CD predictions that separately did not resemble the experimental spectrum. Energy differences were predicted at various theoretical levels, including MP2 and density functional theory. When the predicted CD spectra for each conformation were multiplied by Boltzmann weighting factors created using heats of formation determined by the AM1 optimizations, the weighted composite CD spectrum created did resemble experiment for the pi-pi* transition indicating that both conformations may exist simultaneously in solution. PMID:12605604

Lowe, S L; Pandey, R R; Czlapinski, J; Kie-Adams, G; Hoffmann, M R; Thomasson, K A; Pierce, K S

2003-04-01

22

Introduction of a pi-pi interaction at the active site of a cupredoxin: characterization of the Met16Phe Pseudoazurin mutant.  

PubMed

The Met16Phe mutant of the type 1 copper protein pseudoazurin (PACu), in which a phenyl ring is introduced close to the imidazole moiety of the His81 ligand, has been characterized. NMR studies indicate that the introduced phenyl ring is parallel to the imidazole group of His81. The mutation has a subtle effect on the position of the two S(Cys)-->Cu(II) ligand-to-metal charge transfer bands in the visible spectrum of PACu(II) and a more significant influence on their intensities resulting in a A(459)/A(598) ratio of 0.31 for Met16Phe as compared to a A(453)/A(594) ratio of 0.43 for wild-type PACu(II) at pH 8. The electron paramagnetic resonance spectrum of the Met16Phe variant is more axial than that of the wild-type protein, and the resonance Raman spectrum of the mutant exhibits subtle differences. A C(gamma)H proton of Met86 exhibits a much smaller hyperfine shift in the paramagnetic (1)H NMR spectrum of Met16Phe PACu(II) as compared to its position in the wild-type protein, which indicates a weaker axial Cu-S(Met86) interaction in the mutant. The Met16Phe mutation results in an approximately 60 mV increase in the reduction potential of PACu. The pK(a) value of the ligand His81 decreases from 4.9 in wild-type PACu(I) to 4.5 in Met16Phe PACu(I) indicating that the pi-pi contact with Phe16 stabilizes the Cu-N(His81) interaction. The Met16Phe variant of PACu has a self-exchange rate constant at pH 7.6 (25 degrees C) of 9.8 x 10(3) M(-)(1) s(-)(1) as compared to the considerably smaller value of 3.7 x 10(3) M(-)(1) s(-)(1) for the wild-type protein under identical conditions. The enhanced electron transfer reactivity of Met16Phe PACu is a consequence of a lower reorganization energy due to additional active site rigidity caused by the pi-pi interaction between His81 and the introduced phenyl ring. PMID:12779340

Yanagisawa, Sachiko; Sato, Katsuko; Kikuchi, Makiko; Kohzuma, Takamitsu; Dennison, Christopher

2003-06-10

23

Absorption and resonance Raman spectra of Eu sup III (porphyrin) sub 2 sup + complexes. Oxidation-induced enhancement of porphyrin-porphyrin. pi. pi. interaction  

SciTech Connect

Absorption and resonance Raman spectra are reported for the lanthanide porphyrin sandwich complexes Eu{sup III}(OEP){sub 2}{sup +}, Eu{sup III}(TPnP){sub 2}{sup +}, and Eu{sup III}(TPP){sub 2}{sup +} (OEP = octaethylporphyrin, TPnP = meso-tetrapentylporphyrin and TPP = mesotetraphenylporphyrin). These cations contain two holes in the porphyrin {pi} system; consequently, they are electronically similar to solution cation dimers of the form (MOEP{sup +}){sub 2}. All three of the double-hole sandwich complexes exhibit spectral features characteristic of strong {pi}{pi} interactions. In particular, a near-infrared (near-IR)absorption band is observed at 861 nm (Eu{sup III}(OEP){sub 2}{sup +}), 867 nm (Eu{sup III}(TPnP){sub 2}{sup +}), and 1,025 nm (Eu{sup III}(TPP){sub 2}{sup +}). The energies of these near-IR bands are significantly higher than those of the corresponding single-hole complexes. The blue shift of the near-IR absorption maximum of all three double-hole sandwiches undergoes a substantial blue shift as the temperature is lowered from room temperature to 11 K.

Perng, Jinghuei; Duchowski, J.K.; Bocian, D.F. (Carnegie Mellon Univ., Pittsburgh, PA (USA))

1991-02-07

24

A new Coulomb correction method for Bose-Einstein correlations, based on the $\\\\pi^+\\\\pi^-$ correlation measurements  

Microsoft Academic Search

We present the measured correlation functions for $\\\\pi^+\\\\pi^-$, $\\\\pi^-\\\\pi^-$ and $\\\\pi^+\\\\pi^+$ pairs in central S+Ag collisions at 200 GeV per nucleon. The Gamov function, which has been traditionally used to correct the correlation functions of charged pions for the Coulomb interaction, is found to be inconsistent with all measured correlation functions. Certain problems which have been dominating the systematic uncertainty

J. Bartke; H. Bialkowska; R. Bock; D. Brinkmann; R. Brockmann; P. Chan; I. Derado; B. Eberlein; V. Eckardt; J. Eschke; D. Ferenc; B. Fleischmann; P. Foka; P. Freund; M. Fuchs; M. Hoffmann; P. Jacobs; S. Kabana; K. Kadija; J. Kosiec; M. Kowalski; M. Lahanas; A. Ljubi; S. Margetis; R. Morse; E. Nappi; G. Odyniec; A. Petridis; A. Piper; F. Posa; W. Rauch; R. Renfordt; W. Retyk; G. Roland; H. Rothard; K. Runge; A. Sandoval; J. Schambach; N. Schmitz; E. Schmoetten; I. Schneider; R. Sendelbach; P. Seyboth; J. Seyerlein; E. Skrzypczak; P. Stefansky; L. Teitelbaum; S. Tonse; G. Vasileiadis; M. Vassiliou; S. Wenig; M. Wensveen; B. Wosiek

1997-01-01

25

Jets Produced in pi-, pi+, and Proton Interactions at 200 GeV on Hydrogen and Aluminum Targets  

Microsoft Academic Search

This paper presents results from an experiment on the production of jets (groups of particles) with high p? produced in 200-GeV\\/c interactions. Results are presented on the comparison of jet cross sections on aluminum and hydrogen targets. The jet fragmentation distributions are also examined. Both the cross section and the jet structure are found to depend strongly on the beam

C. Bromberg; G. Fox; R. Gomez; J. Pine; J. Rohlf; S. Stampke; K. Yung; S. Erhan; E. Lorenz; M. Medinnis; P. Schlein; V. Ashford; H. Haggerty; R. Juhala; E. Malamud; S. Mori; R. Abrams; R. Delzenero; H. Goldberg; S. Margulies; D. McLeod; J. Solomon; R. Stanek; A. Dzierba; W. Kropac

1979-01-01

26

Spectroscopic characterization of triple-decker lanthanide porphyrin sandwich complexes. Effects of strong. pi. pi. interactions in extended assemblies  

Microsoft Academic Search

Electrochemical, optical absorption, near-infrared, infrared, resonance Raman, and electron paramagnetic resonance data are reported for several neutral and singly oxidized triple-decker lanthanide porphyrin sandwich complexes Lnâ(OEP)â (Ln = La(III), Ce(III), Eu(III); OEP = octaethylporphyrin). The data indicate that there are strong ÏÏ interactions between the porphyrin macrocycles in all of the complexes. As a consequence, the hole in the porphyrin

John K. Duchowski; David F. Bocian

1990-01-01

27

Computational characterization and modeling of buckyball tweezers: density functional study of concave-convex pi...pi interactions.  

PubMed

The geometries and binding energies of a recent buckyball tweezers (C(60)H(28)) and its supramolecular complexes are investigated using recently developed density functionals (M06-L and M06-2X) that include an accurate treatment of medium-range correlation energy. The pincer part of the tweezers, corannulene, has a strong attractive interaction with C(60). However, due to the entropy penalty, the calculated gas-phase free energy of association of the C(60)@corannulene supramolecule is positive 3.5 kcal mol(-1); and this entropy penalty explains why it is difficult to observe C(60)@corannulene supramolecule experimentally. By using a pi-extended tetrathiafulvalene (TTF), in particular 9,10-bis(1,3-dithiol-2-ylidene)-9,10-dihydroanthracene (TTFAQ or C(20)H(10)S(4)), as the pincer part, we modeled a new buckyball tweezers. The geometries and binding energies of the new buckyball tweezers and its supramolecular complexes are also calculated. Due to fact that the attractive interaction between TTFAQ and C(60) is weaker than that between corannulene and C(60), the gas-phase binding free energy in the C(60)@C(60)H (32)S(8) supramolecular complex is smaller than that in the C(60)@C(60)H(28) supramolecule. We also discuss solvent effects. PMID:18464998

Zhao, Yan; Truhlar, Donald G

2008-05-21

28

The reaction gammap --> ppi+pi-pi+pi- for photon energies from 25 to 70 GeV  

Microsoft Academic Search

Measurements of the reaction gammap --> ppi+pi-pi+pi- are presented, in which pi+pi-pi+pi- systems with masses up to 3 GeV are produced from fragmentation of the incident photon. The reaction is dominated by production of the large peak of the varrho'(1600) meson and, at higher masses >~2 GeV, y production of jet-like 4pi systems. The varrho'(1600) meson is produced by a

D. Aston; M. Atkinson; R. Bailey; A. H. Ball; B. Bouquet; G. R. Brookes; J. Bröring; Peter J Bussey; D. Clarke; A. B. Clegg; B. D'Almagne; G. de Rosny; B. Diekmann; Alexander Donnachie; M. Draper; B. Drevillon; I. P. Duerdoth; J.-P. Dufey; R. J. Ellison; D. Ezra; P. Feller; A. Ferrer; P. J. Flynn; F. Friese; William Galbraith; R. George; S. D. M. Gill; M. Goldberg; S. Goodman; W. Graves; B. Grossetête; P. G. Hampson; K. Heinloth; R. E. Hughes-Jones; J. S. Hutton; M. Ibbotson; M. Jung; S. Katsanevas; M. A. R. Kemp; F. Kovacs; B. R. Kumar; G. D. Lafferty; J. M. Lévy; V. Liebenau; John Litt; G W London; D. Mercer; J. V. Morris; K. Müller; D. Newton; E. Paul; P. Petroff; Y. Pons; C. Raine; F. Richard; R H Richter; J. H. C. Roberts; Patrick Roudeau; A. Rougé; M. Rumpf; M. Sené; Ian O Skillicorn; J. C. Sleeman; K. M. Smith; C. Steinhauer; Kenneth Mick Storr; R. J. Thompson; D. Treille; Ch. de La Vaissière; H L Videau; I. Videau; A. P. Waite; A. Wijangco; W. Wojcik; J.-P. Wuthrick; T. P. Yiou

1981-01-01

29

A study of the decay mode KLO --> pi+pi-piO  

Microsoft Academic Search

The decay process KLO-->pi+pi-piO has been studied in the 3OKLO beam at the Stanford Linear Accelerator Center using a wire chamber magnetic spectrometer. The three pion decay was separated from leptonic decays using kinematics and muon identification. The average detection efficiency is 58.5% with a variation of less than 10% over the Dalitz plot. For a matrix expressed as M2=1+2aoMK\\/M2pi+(2

C. D. Buchanan; D. J. Drickey; F. D. Rudnick; P. F. Shepard; D. R. Stork; H. K. Ticho; C.-Y. Chien; B. Cox; L. Ettlinger; L. Resvanis; R. A. Zdanis; E. Dally; E. Seppi; P. Innocenti

1970-01-01

30

Measurement of the branching ratio and pi° energy spectrum for K°L --> pi+pi-pi°  

Microsoft Academic Search

The K°L --> pi+pi-pi° decay was studied in a bubble chamber experiment at an average momentum of 1.3 GeV\\/c. We measure the branching ration Gamma(K°L --> pi+pi-pi°)\\/Gamma(K°L --> charged) to be 0.1605 +\\/- 0.0038. The data are well fitted with a linear matrix element in the pi° kinetic energy with a slope g = 0.612 +\\/- 0.032. On leave from

G. Alexander; O. Benary; I. Borowitz; K. Lande; Y. Oren; I. Stumer; E. Burkhardt; H. Filthuth; A. Putzer; I. Bar-Nir

1973-01-01

31

Measurement of CP violation parameters with a Dalitz plot analysis of B{+/-}-->D{pi{+}pi{-}pi{0}}K{+/-}.  

PubMed

We report the results of a CP violation analysis of the decay B{+/-}-->D{pi{+}pi{-}pi;{0}}K{+/-}, where D{pi{+}pi{-}pi{0}} indicates a neutral D meson detected in the final state pi{+}pi{-}pi{0}, excluding K{S}{0}pi{0}. The analysis makes use of 324 x 10{6}e{+}e{-}-->BB[over ] events recorded by the BABAR experiment at the PEP-II e;{+}e;{-} storage ring. Analyzing the pi;{+}pi;{-}pi;{0} Dalitz plot distribution and the B{+/-}-->D{pi{+}pi{-}pi{0}}K{+/-} branching fraction and decay rate asymmetry, we find the following one-standard-deviation constraints on the amplitude ratio and on the weak and strong phases: 0.06pi{+}pi{-}pi{0} decay amplitude. PMID:18233513

Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Grauges, E; Lopez, L; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Pegna, D Lopes; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Tackmann, K; Wenzel, W A; Del Amo Sanchez, P; Barrett, M; Harrison, T J; Hart, A J; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Williams, D C; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Nikolich, M B; Vazquez, W Panduro; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L

2007-12-21

32

Search for the photoexcitation of exotic mesons in the pi+pi+pi- system.  

PubMed

A search for exotic mesons in the pi;{+}pi;{+}pi;{-} system photoproduced by the charge exchange reaction gammap-->pi;{+}pi;{+}pi;{-}(n) was carried out by the CLAS Collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A partial wave analysis was performed on a sample of 83 000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic J;{PC}=1;{-+} resonant state in the 1 to 2 GeV mass range. Our partial wave analysis shows production of the a_{2}(1320) and the pi_{2}(1670) mesons, but no evidence for the a_{1}(1260), nor the pi_{1}(1600) exotic state at the expected levels. An upper limit of 13.5 nb is determined for the exotic pi_{1}(1600) cross section, less than 2% of the a_{2}(1320) production. PMID:19392105

Nozar, M; Salgado, C; Weygand, D P; Guo, L; Adams, G; Li, Ji; Eugenio, P; Amaryan, M J; Anghinolfi, M; Asryan, G; Avakian, H; Bagdasaryan, H; Baillie, N; Ball, J P; Baltzell, N A; Barrow, S; Battaglieri, M; Bedlinskiy, I; Bektasoglu, M; Bellis, M; Benmouna, N; Berman, B L; Biselli, A S; Blaszczyk, L; Bonner, B E; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Burkert, V D; Butuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Carnahan, B; Casey, L; Cazes, A; Chen, S; Cheng, L; Cole, P L; Collins, P; Coltharp, P; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Crede, V; Cummings, J P; Dale, D; Dashyan, N; De Masi, R; De Vita, R; De Sanctis, E; Degtyarenko, P V; Denizli, H; Dennis, L; Deur, A; Dharmawardane, K V; Dhuga, K S; Dickson, R; Djalali, C; Dodge, G E; Doughty, D; Dugger, M; Dytman, S; Dzyubak, O P; Egiyan, H; Egiyan, K S; El Fassi, L; Elouadrhiri, L; Fatemi, R; Fedotov, G; Feuerbach, R J; Forest, T A; Fradi, A; Funsten, H; Garçon, M; Gavalian, G; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gothe, R W; Griffioen, K A; Guidal, M; Guillo, M; Guler, N; Gyurjyan, V; Hadjidakis, C; Hafidi, K; Hakobyan, H; Hanretty, C; Hardie, J; Hassall, N; Heddle, D; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Ito, M M; Jenkins, D; Jo, H S; Johnstone, J R; Joo, K; Juengst, H G; Kalantarians, N; Kellie, J D; Khandaker, M; Kim, W; Klein, A; Klein, F J; Kossov, M; Krahn, Z; Kramer, L H; Kubarovsky, V; Kuhn, J; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Livingston, K; Lu, H Y; Maccormick, M; Markov, N; Mattione, P; McAleer, S; McKinnon, B; McNabb, J W C; Mecking, B A; Mehrabyan, S; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Mirazita, M; Miskimen, R; Mokeev, V; Moreno, B; Moriya, K; Morrow, S A; Moteabbed, M; Mueller, J; Munevar, E; Mutchler, G S; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niroula, M R; Niyazov, R A; O'Rielly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Pasyuk, E; Paterson, C; Anefalos Pereira, S; Philips, S A; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O; Polli, E; Popa, I; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Ronchetti, F; Rosner, G; Rossi, P; Rubin, P D; Sabatié, F; Salamanca, J; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Sharabian, Y G; Sharov, D; Shvedunov, N V; Skabelin, A V; Smith, E S; Smith, L C; Sober, D I; Sokhan, D; Stavinsky, A; Stepanyan, S S; Stepanyan, S; Stokes, B E; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tedeschi, D J; Thoma, U; Tkabladze, A; Tkachenko, S; Todor, L; Ungaro, M; Vineyard, M F; Vlassov, A V; Watts, D P; Weinstein, L B; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Zana, L; Zhang, J; Zhao, B; Zhao, Z W

2009-03-13

33

How large are the rates of the {ital CP}-violating {eta},{eta}{prime}{r_arrow}{pi}{pi} decays?  

SciTech Connect

The rates of {eta},{eta}{prime}{r_arrow}{pi}{pi} are computed in the framework of the standard electroweak model. The results {ital B}({eta}{r_arrow}{pi}{pi}){le}2{times}10{sup {minus}27} and {ital B}({eta}{prime}{r_arrow}{pi}{pi}){le}3{times}10{sup {minus}29} imply that a search for these decays at the existing and planned {eta}({eta}{prime}) factories would indeed be a search for {ital CP} violation in strong interactions or unconventional mechanisms of {ital CP} violation.

Jarlskog, C.; Shabalin, E. [Department of Mathematical Physics, LTH, Lund University, Box 118, S-22100 Lund (Sweden)] [Department of Mathematical Physics, LTH, Lund University, Box 118, S-22100 Lund (Sweden)

1995-07-01

34

Experimental study of psi2S decays to K+K-pi+pi-pi0 final states  

Microsoft Academic Search

K+K-pi+pi-pi0 final states are studied using a sample of 14×106 psi(2S) decays collected with the Beijing Spectrometer (BESII) at the Beijing Electron-Positron Collider. The branching fractions of psi(2S) decays to K+K-pi+pi-pi0, omegaK+K-, omegaf0(1710), K*(892)0K-pi+pi0+c.c., K*(892)+K-pi+pi-+c.c., K*(892)+K-rho0+c.c. and K*(892)0K-rho++c.c. are determined. The first two agree with previous measurements, and the last five are first measurements.

M. Ablikim; J. Z. Bai; Y. Ban; J. G. Bian; X. Cai; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; Y. S. Dai; L. Y. Diao; Z. Y. Deng; Q. F. Dong; S. X. Du; J. Fang; S. S. Fang; C. D. Fu; C. S. Gao; Y. N. Gao; S. D. Gu; Y. T. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; M. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. T. Huang; X. B. Ji; X. S. Jiang; X. Y. Jiang; J. B. Jiao; D. P. Jin; S. Jin; Yi Jin; Y. F. Lai; G. Li; H. B. Li; H. H. Li; J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; X. N. Li; X. Q. Li; Y. L. Li; Y. F. Liang; H. B. Liao; B. J. Liu; C. X. Liu; F. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. Liu; J. P. Liu; Q. Liu; R. G. Liu; Z. A. Liu; Y. C. Lou; F. Lu; G. R. Lu; J. G. Lu; C. L. Luo; F. C. Ma; H. L. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; Z. P. Mao; X. H. Mo; J. Nie; S. L. Olsen; H. P. Peng; R. G. Ping; N. D. Qi; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; C. P. Shen; D. L. Shen; X. Y. Shen; H. Y. Sheng; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; Z. Q. Tan; X. Tang; G. L. Tong; G. S. Varner; D. Y. Wang; L. Wang; M. Wang; P. Wang; W. F. Wang; Y. F. Wang; Z. Wang; Zheng Wang; C. L. Wei; D. H. Wei; N. Wu; X. M. Xia; X. X. Xie; G. F. Xu; X. P. Xu; Y. Xu; M. L. Yan; H. X. Yang; Y. X. Yang; M. H. Ye; Y. X. Ye; Z. Y. Yi; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Q. Zhang; H. Y. Zhang; J. W. Zhang; J. Y. Zhang; S. H. Zhang; X. M. Zhang; X. Y. Zhang; Yiyun Zhang; Z. P. Zhang; D. X. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; Z. P. Zheng; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2006-01-01

35

Assessment of Standard Force Field Models against High-Quality ab initio Potential Curves for Prototypes of pi-pi, CH/pi, and SH/pi Interactions  

SciTech Connect

Several popular force fields, namely, CHARMM, AMBER, OPLS-AA, and MM3, have been tested for their ability to reproduce highly accurate quantum mechani- cal potential energy curves for noncovalent interactions in the benzene dimer, the benzene-CH4 complex, and the benzene-H2S complex. All of the force fields are semi-quantitatively correct, but none of them is consistently reliable quantitatively. Re-optimization of Lennard-Jones parameters and symmetry-adapted perturbation theory analysis for the benzene dimer suggests that better agreement cannot be expected unless more flexible functional forms (particularly for the electrostatic contributions)are employed for the empirical force fields.

Sumpter, Bobby G [ORNL; Sherrill, David [Georgia Institute of Technology; Sinnokrot, Mutasem O [University of Jordan; Marshall, Michael S. [Georgia Institute of Technology; Hohenstein, Edward G. [Georgia Institute of Technology; Walker, Ross [San Diego Supercomputer Center; Gould, Ian R [ORNL

2009-01-01

36

Measurement of the ratios of branching fractions B(B0s --> Ds- pi+ pi+ pi-)/B(B0-->D- pi+ pi+ pi-) and B(B0s --> Ds- pi+)/B(B0-->D- pi+).  

PubMed

Using 355 pb;{-1} of data collected by the CDF II detector in pp[over ] collisions at sqrt[s]=1.96 TeV at the Fermilab Tevatron, we study the fully reconstructed hadronic decays B_{(s)};{0}-->D_{(s)};{-}pi;{+} and B_{(s)};{0}-->D_{(s)};{-}pi;{+}pi;{+}pi;{-}. We present the first measurement of the ratio of branching fractions B(B_{s};{0}-->D_{s};{-}pi;{+}pi;{+}pi;{-})/B(B;{0}-->D;{-}pi;{+}pi;{+}pi;{-})=1.05+/-0.10(stat)+/-0.22(syst). We also update our measurement of B(B_{s};{0}-->D_{s};{-}pi;{+})/B(B;{0}-->D;{-}pi;{+}) to 1.13+/-0.08(stat)+/-0.23(syst), improving the statistical uncertainty by more than a factor of 2. We find B(B_{s};{0}-->D_{s};{-}pi;{+})=[3.8+/-0.3(stat)+/-1.3(syst)]x10;{-3} and B(B_{s};{0}-->D_{s};{-}pi;{+}pi;{+}pi;{-})=[8.4+/-0.8(stat)+/-3.2(syst)]x10;{-3}. PMID:17358931

Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Budroni, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Cyr, D; DaRonco, S; D'Auria, S; Davies, T; D'Onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; Dituro, P; Dörr, C; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kovalev, A; Kraan, A C; Kraus, J; Kravchenko, I; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Manca, G; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Nagano, A; Naganoma, J; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I

2007-02-01

37

Electroweak Penguin Hunting Through B -> pi pi,pi K and Rare K and B Decays  

NASA Astrophysics Data System (ADS)

The $B\\to\\pi K$ decays with significant electroweak penguin contributions show a puzzling pattern. We explore this "$B\\to\\pi K$ puzzle" through a systematic strategy. The starting point, which is essentially unaffected by electroweak penguins, is the determination of the angle $\\gamma$ of the unitarity triangle through the CP-violating $B^0_d\\to\\pi^+\\pi^-$, $B^0_d\\to\\pi^-K^+$ asymmetries, yielding $\\gamma=(73.9^{+5.8}_{-6.5})^\\circ$, and the extraction of hadronic parameters through the measured $B\\to\\pi\\pi$ branching ratios. Using arguments related to the SU(3) flavour symmetry, we convert the hadronic $B\\to\\pi\\pi$ parameters into their $B\\to\\pi K$ counterparts, allowing us to predict the $B\\to\\pi K$ observables in the Standard Model. We find agreement with the data for those quantities that are only marginally affected by electroweak penguins, while this is not the case for the observables with sizeable electroweak penguin contributions. Since we may also perform a couple of internal consistency checks of our working assumptions, which are nicely satisfied for the current data, and find a small sensitivity of our results to large non-factorizable SU(3)-breaking corrections, the "$B\\to\\pi K$" puzzle may be due to new physics in the electroweak penguin sector. We show that it can indeed be resolved through such a kind of new physics with a large CP-violating phase. Further insights into the electroweak penguins are provided by the $B^+\\to\\pi^0K^+$ and $B_d^0\\to\\pi^0K_{\\rm S}$ CP asymmetries, and in particular through correlations with various rare $K$ and B decays.

Buras, A. J.; Fleischer, R.; Recksiegel, S.; Schwab, F.

38

Observation of Upsilon(4S) decays to pi(+)pi(-)Upsilon(1S) and pi(+)pi(-)Upsilon(2S).  

PubMed

Observation of Upsilon(4S) decays to pi(+)pi(-)C and pi(+)pi(-)Upsilon(2S)We present the first measurement of Upsilon(4S) decays to pi(+)pi(-)Upsilon(1S) based on a sample of 230 x 106(4S) mesons collected with the BABAR detector. We measure the product branching fractions Beta(Upsilon(4S) --> pi(+)pi(-)Upsilon(1S)) x BetaUpsilon(1S) --> mu(+)mu(-) = (2.23 +/- 0.25(stat) +/- 0.27(syst))x 10(-6) and Beta(Upsilon(4S) --> pi(+)pi(-)Upsilon(2S) x Beta(Upsilon(2S) --> mu(+)mu(-))=(1.69 +/-0.26(stat) +/- 0.20(syst)) x 10(-)6, from which we derive the partial widths Gamma(Upsilon(4S) --> pi(+)pi(-)Upsilon(1S))=(1.8 +/-0.4) keV and Gamma(Upsilon(4S) --> pi(+)pi(-)Upsilon(2S))=(2.7 +/- 0.8) keV. PMID:16803371

Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Andreassen, R; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Gaillard, J R; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Brown, C L; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Kelly, M P; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Willocq, S Y; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Del Re, D; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Potter, C T; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Galeazzi, F; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C

2006-06-16

39

Stacking interactions and DNA intercalation  

SciTech Connect

The relationship between stacking interactions and the intercalation of proflavine and ellipticine within DNA is investigated using a nonempirical van der Waals density functional for the correlation energy. Our results, employing a binary stack model, highlight fundamental, qualitative differences between base-pair base-pair interactions and that of the stacked intercalator base pair system. Most notable result is the paucity of torque which so distinctively defines the Twist of DNA. Surprisingly, this model, when combined with a constraint on the twist of the surrounding base-pair steps to match the observed unwinding of the sugar-phosphate backbone, was sufficient for explaining the experimentally observed proflavine intercalator configuration. Our extensive mapping of the potential energy surface of base-pair intercalator interactions can provide valuable information for future nonempirical studies of DNA intercalation dynamics.

Li, Dr. Shen [Fred Hutchinson Cancer Research Center; Cooper, Valentino R [ORNL; Thonhauser, Prof. Timo [Wake Forest University, Winston-Salem, NC; Lundqvist, Prof. Bengt I. [Chalmers University of Technology, Sweden; Langreth, David C. [Rutgers University

2009-01-01

40

Measurements of J\\/psi decays into 2(pi+pi-)eta and 3(pi+pi-)eta  

Microsoft Academic Search

Based on a sample of 5.8×107J\\/psi events taken with the BESII detector, the branching fractions of J\\/psi-->2(pi+pi-)eta and J\\/psi-->3(pi+pi-)eta are measured for the first time to be (2.26±0.08±0.27)×10-3 and (7.24±0.96±1.11)×10-4, respectively.

M. Ablikim; J. Z. Bai; Y. Ban; J. G. Bian; X. Cai; J. F. Chang; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Jin Chen; Jun Chen; M. L. Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; H. L. Dai; Y. S. Dai; Z. Y. Deng; L. Y. Dong; Q. F. Dong; S. X. Du; Z. Z. Du; J. Fang; S. S. Fang; C. D. Fu; H. Y. Fu; C. S. Gao; Y. N. Gao; M. Y. Gong; W. X. Gong; S. D. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; M. He; X. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. P. Huang; X. T. Huang; X. B. Ji; C. H. Jiang; X. S. Jiang; D. P. Jin; S. Jin; Y. Jin; Y. F. Lai; F. Li; G. Li; H. H. Li; J. Li; Q. J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; X. Q. Li; Y. L. Li; Y. F. Liang; H. B. Liao; C. X. Liu; F. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. Liu; J. P. Liu; R. G. Liu; Z. A. Liu; Z. X. Liu; F. Lu; G. R. Lu; H. J. Lu; J. G. Lu; C. L. Luo; L. X. Luo; X. L. Luo; F. C. Ma; H. L. Ma; J. M. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; X. Y. Ma; Z. P. Mao; X. H. Mo; J. Nie; Z. D. Nie; S. L. Olsen; H. P. Peng; N. D. Qi; C. D. Qian; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; D. L. Shen; X. Y. Shen; H. Y. Sheng; F. Shi; X. Shi; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; X. Tang; N. Tao; Y. R. Tian; G. L. Tong; G. S. Varner; D. Y. Wang; J. Z. Wang; K. Wang; L. Wang; M. Wang; P. Wang; S. Z. Wang; W. F. Wang; Y. F. Wang; Z. Wang; Zheng Wang; C. L. Wei; D. H. Wei; N. Wu; Y. M. Wu; X. M. Xia; X. X. Xie; B. Xin; G. F. Xu; H. Xu; S. T. Xue; M. L. Yan; F. Yang; H. X. Yang; J. Yang; Y. X. Yang; M. Ye; Y. X. Ye; L. H. Yi; Z. Y. Yi; C. S. Yu; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Y. Zhang; J. Zhang; Q. J. Zhang; S. Q. Zhang; X. M. Zhang; X. Y. Zhang; Y. Y. Zhang; Yiyun Zhang; Z. P. Zhang; Z. Q. Zhang; D. X. Zhao; J. B. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; X. J. Zhao; Y. B. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; L. S. Zheng; Z. P. Zheng; X. C. Zhong; B. Q. Zhou; G. M. Zhou; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2005-01-01

41

Effect of unitarization on the amplitudes for the decays K{sub 1}{sup 0} {sup {yields} {pi}+{pi}-} and K{sup +} {sup {yields} {pi}+{pi}+{pi}-}  

SciTech Connect

The unitarization of the amplitude for the decay process K{sub 1}{sup 0} {sup {yields} {pi}+{pi}-} and allowance for the rescattering of final-state pions in the decay process K{sup +} {sup {yields} {pi}+{pi}+{pi}-} make it possible to evaluate, by using the parameters extracted from data on K {sup {yields}}2{pi} decays, the K{sup +} {sup {yields} {pi}+{pi}+{pi}-} decay width. The result agrees with the experimental width value at a level of a few percent. Allowance for corrections for higher order terms of the momentum expansion of the amplitude for the decay process K{sup +} {sup {yields} {pi}+{pi}+{pi}-} leads to the slope-parameter value of g{sub ++-}{sup th} = 0.2182, which agrees with its experimental counterpart, g{sub ++-}{sup exp} = 0.2154 {+-} 0.0035.

Shabalin, E. P., E-mail: shabalin@itep.r [Institute of Theoretical and Experimental Physics (Russian Federation)

2010-11-15

42

Can the hybrid meta GGA and DFT-D methods describe the stacking interactions in conjugated polymers?  

PubMed

Newly developed hybrid meta density functionals and density functionals augmented by a classical London dispersion term have been systematically applied for the description of stacking energy and intermolecular distance of thiophene dimer and substituted thiophene dimer. The performance of the various approaches is compared with the benchmark ab-initio calculations done with CCSD(T) (Tsuzuki et al., JACS 2002, 124, 12200). Our results indicate that, contrary to the previous DFT methods which are not reliable, the new generation of DFT performs better the stacking interactions. These functionals, and especially those with an empirical correction, are suitable for general application in conducting polymers and, in particular, the modeling of solid state in which the overlap of Pi-Pi interactions between the conjugated chains is important. PMID:18785244

Dkhissi, Ahmed; Ducéré, Jean Marie; Blossey, Ralf; Pouchan, Claude

2009-06-01

43

pi-(pi)scattering lengths at finite temperature.  

National Technical Information Service (NTIS)

The s-wave (pi)-(pi) scattering lengths a(sup I)(T) at finite temperature T and isospin I=0,2 are calculated within the SU(2) Nambu-Jona-Lasinio model. a(sup 2)(T) dislays a singularity at the Mott temperature T(sub M), defined as m(sub (pi))(T(sub M))=2m...

E. Quack, P. Zhuang, Y. Kalinovsky, S. P. Klevansky, J. Huefner

1994-01-01

44

Dispersion relation bounds for {pi}{pi} scattering  

SciTech Connect

Axiomatic principles such as analyticity, unitarity, and crossing symmetry constrain the second derivative of the {pi}{pi} scattering amplitudes in some channels to be positive in a region of the Mandelstam plane. Since this region lies in the domain of validity of chiral perturbation theory, we can use these positivity conditions to bound linear combinations of l{sub 1} and l{sub 2}. We compare our predictions with those derived previously in the literature using similar methods. We compute the one-loop {pi}{pi} scattering amplitude in the linear sigma model (LSM) using the MS scheme, a result hitherto absent in the literature. The LSM values for l{sub 1} and l{sub 2} violate the bounds for small values of m{sub {sigma}}/m{sub {pi}}. We show how this can occur, while still being consistent with the axiomatic principles.

Manohar, Aneesh V.; Mateu, Vicent [Department of Physics, University of California at San Diego, La Jolla, California 92093 (United States); Departament de Fisica Teorica, IFIC, Universitat de Valencia-CSIC, Apt. Correus 22085, E-46071 Valencia (Spain)

2008-05-01

45

Testing the dynamics of B ->pi pi and constraints onalpha  

SciTech Connect

In charmless nonleptonic B decays to {pi}{pi} or {rho}{rho}, the ''color allowed'' and ''color suppressed'' tree amplitudes can be studied in a systematic expansion in {alpha}{sub s}(m{sub b}) and {Lambda}{sub QCD}/m{sub b}. At leading order in this expansion their relative strong phase vanishes. The implications of this prediction are obscured by penguin contributions. They propose to use this prediction to test the relative importance of the various penguin amplitudes using experimental data. The present B {yields} {pi}{pi} data suggest that there are large corrections to the heavy quark limit, which can be due to power corrections to the tree amplitudes, large up-penguin amplitude, or enhanced weak annihilation. Because the penguin contributions are smaller, the heavy quark limit is more consistent with the B {yields} {rho}{rho} data, and its implications may become important for the extraction of {alpha} from this mode in the future.

Grossman, Yuval; Hocker, Andreas; Ligeti, Zoltan; Pirjol, Dan

2005-07-07

46

Measurement of the branching fractions of psi(2S)-->3(pi+pi-) and J\\/psi-->2(pi+pi-)  

Microsoft Academic Search

Using data samples collected at &surd;(s)=3.686 GeV and 3.650 GeV by the BESII detector at the BEPC, the branching fraction of psi(2S)-->3(pi+pi-) is measured to be [5.45±0.42(stat)±0.87(syst)]×10-4, and the relative branching fraction of J\\/psi-->2(pi+pi-) to that of J\\/psi-->mu+mu- is measured to be [6.01±0.20(stat)±0.48(syst)]% via psi(2S)-->pi+pi-J\\/psi,J\\/psi-->2(pi+pi-). The electromagnetic form factor of 3(pi+pi-) is determined to be 0.19±0.02 and 0.24±0.02 at &surd;(s)=3.650

M. Ablikim; J. Z. Bai; Y. Ban; J. G. Bian; X. Cai; J. F. Chang; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Jin Chen; Jun Chen; M. L. Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; H. L. Dai; Y. S. Dai; Z. Y. Deng; L. Y. Dong; Q. F. Dong; S. X. Du; Z. Z. Du; J. Fang; S. S. Fang; C. D. Fu; H. Y. Fu; C. S. Gao; Y. N. Gao; M. Y. Gong; W. X. Gong; S. D. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; M. He; X. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. P. Huang; X. T. Huang; X. B. Ji; C. H. Jiang; X. S. Jiang; D. P. Jin; S. Jin; Y. Jin; Y. F. Lai; F. Li; G. Li; H. B. Li; H. H. Li; J. Li; Q. J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; X. Q. Li; Y. L. Li; Y. F. Liang; H. B. Liao; C. X. Liu; F. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. Liu; J. P. Liu; R. G. Liu; Z. A. Liu; Z. X. Liu; F. Lu; G. R. Lu; H. J. Lu; J. G. Lu; C. L. Luo; L. X. Luo; X. L. Luo; F. C. Ma; H. L. Ma; J. M. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; X. Y. Ma; Z. P. Mao; X. H. Mo; J. Nie; Z. D. Nie; S. L. Olsen; H. P. Peng; N. D. Qi; C. D. Qian; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; D. L. Shen; X. Y. Shen; H. Y. Sheng; F. Shi; X. Shi; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; X. Tang; N. Tao; Y. R. Tian; G. L. Tong; G. S. Varner; D. Y. Wang; J. Z. Wang; K. Wang; L. Wang; M. Wang; P. Wang; S. Z. Wang; W. F. Wang; Y. F. Wang; Z. Wang; Zheng Wang; C. L. Wei; D. H. Wei; N. Wu; Y. M. Wu; X. M. Xia; X. X. Xie; B. Xin; G. F. Xu; H. Xu; S. T. Xue; M. L. Yan; F. Yang; H. X. Yang; J. Yang; Y. X. Yang; M. Ye; Y. X. Ye; L. H. Yi; Z. Y. Yi; C. S. Yu; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Y. Zhang; J. Zhang; Q. J. Zhang; S. Q. Zhang; X. M. Zhang; X. Y. Zhang; Y. Y. Zhang; Yiyun Zhang; Z. P. Zhang; Z. Q. Zhang; D. X. Zhao; J. B. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; X. J. Zhao; Y. B. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; L. S. Zheng; Z. P. Zheng; X. C. Zhong; B. Q. Zhou; G. M. Zhou; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2005-01-01

47

Measurement of CP Violation Parameters with a Dalitz Plot Analysis of B±-->Dpi+pi-pi0K±  

Microsoft Academic Search

We report the results of a CP violation analysis of the decay B±-->Dpi+pi-pi0K±, where Dpi+pi-pi0 indicates a neutral D meson detected in the final state pi+pi-pi0, excluding KS0pi0. The analysis makes use of 324×106 e+e--->BB¯ events recorded by the BABAR experiment at the PEP-II e+e- storage ring. Analyzing the pi+pi-pi0 Dalitz plot distribution and the B±-->Dpi+pi-pi0K± branching fraction and decay

B. Aubert; M. Bona; D. Boutigny; Y. Karyotakis; J. P. Lees; V. Poireau; X. Prudent; V. Tisserand; A. Zghiche; E. Grauges; L. Lopez; A. Palano; J. C. Chen; N. D. Qi; G. Rong; P. Wang; Y. S. Zhu; G. Eigen; I. Ofte; B. Stugu; G. S. Abrams; M. Battaglia; D. N. Brown; J. Button-Shafer; R. N. Cahn; Y. Groysman; R. G. Jacobsen; J. A. Kadyk; L. T. Kerth; Yu. G. Kolomensky; G. Kukartsev; D. Lopes Pegna; G. Lynch; L. M. Mir; T. J. Orimoto; M. Pripstein; N. A. Roe; M. T. Ronan; K. Tackmann; W. A. Wenzel; P. Del Amo Sanchez; M. Barrett; T. J. Harrison; A. J. Hart; C. M. Hawkes; A. T. Watson; T. Held; H. Koch; B. Lewandowski; M. Pelizaeus; T. Schroeder; M. Steinke; J. T. Boyd; J. P. Burke; W. N. Cottingham; D. Walker; D. J. Asgeirsson; T. Cuhadar-Donszelmann; B. G. Fulsom; C. Hearty; N. S. Knecht; T. S. Mattison; J. A. McKenna; A. Khan; P. Kyberd; M. Saleem; D. J. Sherwood; L. Teodorescu; V. E. Blinov; A. D. Bukin; V. P. Druzhinin; V. B. Golubev; A. P. Onuchin; S. I. Serednyakov; Yu. I. Skovpen; E. P. Solodov; K. Yu Todyshev; M. Bondioli; M. Bruinsma; M. Chao; S. Curry; I. Eschrich; D. Kirkby; A. J. Lankford; P. Lund; M. Mandelkern; E. C. Martin; D. P. Stoker; S. Abachi; C. Buchanan; S. D. Foulkes; J. W. Gary; F. Liu; O. Long; B. C. Shen; L. Zhang; E. J. Hill; H. P. Paar; S. Rahatlou; V. Sharma; J. W. Berryhill; C. Campagnari; A. Cunha; B. Dahmes; T. M. Hong; D. Kovalskyi; J. D. Richman; T. W. Beck; A. M. Eisner; C. J. Flacco; C. A. Heusch; J. Kroseberg; W. S. Lockman; T. Schalk; B. A. Schumm; A. Seiden; D. C. Williams; M. G. Wilson; L. O. Winstrom; E. Chen; C. H. Cheng; A. Dvoretskii; F. Fang; D. G. Hitlin; I. Narsky; T. Piatenko; F. C. Porter; G. Mancinelli; B. T. Meadows; K. Mishra; M. D. Sokoloff; F. Blanc; P. C. Bloom; S. Chen; W. T. Ford; J. F. Hirschauer; A. Kreisel; M. Nagel; U. Nauenberg; A. Olivas; J. G. Smith; K. A. Ulmer; S. R. Wagner; J. Zhang; A. Chen; E. A. Eckhart; A. Soffer; W. H. Toki; R. J. Wilson; F. Winklmeier; Q. Zeng; D. D. Altenburg; E. Feltresi; A. Hauke; H. Jasper; J. Merkel; A. Petzold; B. Spaan; K. Wacker; T. Brandt; V. Klose; H. M. Lacker; W. F. Mader; R. Nogowski; J. Schubert; K. R. Schubert; R. Schwierz; J. E. Sundermann; A. Volk; D. Bernard; G. R. Bonneaud; E. Latour; Ch. Thiebaux; M. Verderi; P. J. Clark; W. Gradl; F. Muheim; S. Playfer; A. I. Robertson; Y. Xie; M. Andreotti; D. Bettoni; C. Bozzi; R. Calabrese; G. Cibinetto; E. Luppi; M. Negrini; A. Petrella; L. Piemontese; E. Prencipe; F. Anulli; R. Baldini-Ferroli; A. Calcaterra; R. de Sangro; G. Finocchiaro; S. Pacetti; P. Patteri; I. M. Peruzzi; M. Piccolo; M. Rama; A. Zallo; A. Buzzo; R. Contri; M. Lo Vetere; M. M. Macri; M. R. Monge; S. Passaggio; C. Patrignani; E. Robutti; A. Santroni; S. Tosi; K. S. Chaisanguanthum; M. Morii; J. Wu; R. S. Dubitzky; J. Marks; S. Schenk; U. Uwer; D. J. Bard; P. D. Dauncey; R. L. Flack; J. A. Nash; M. B. Nikolich; W. Panduro Vazquez; P. K. Behera; X. Chai; M. J. Charles; U. Mallik; N. T. Meyer; V. Ziegler; J. Cochran; H. B. Crawley; L. Dong; V. Eyges; W. T. Meyer; S. Prell; E. I. Rosenberg; A. E. Rubin; A. V. Gritsan; C. K. Lae; A. G. Denig; M. Fritsch; G. Schott; N. Arnaud; J. Béquilleux; M. Davier; G. Grosdidier; A. Höcker; V. Lepeltier; F. Le Diberder; A. M. Lutz; S. Pruvot; S. Rodier; P. Roudeau; M. H. Schune; J. Serrano; V. Sordini; A. Stocchi; W. F. Wang; G. Wormser; D. J. Lange; D. M. Wright; C. A. Chavez; I. J. Forster; J. R. Fry; E. Gabathuler; R. Gamet; D. E. Hutchcroft; D. J. Payne; K. C. Schofield; C. Touramanis; A. J. Bevan; K. A. George; F. di Lodovico; W. Menges; R. Sacco; G. Cowan; H. U. Flaecher; D. A. Hopkins; P. S. Jackson; T. R. McMahon; F. Salvatore; A. C. Wren; C. L. Davis; J. Allison; N. R. Barlow; R. J. Barlow; Y. M. Chia; C. L. Edgar; G. D. Lafferty; T. J. West; J. I. Yi; C. Chen; W. D. Hulsbergen; A. Jawahery; D. A. Roberts; G. Simi; G. Blaylock; C. Dallapiccola; S. S. Hertzbach; X. Li; T. B. Moore; E. Salvati; S. Saremi; R. Cowan; G. Sciolla; S. J. Sekula; M. Spitznagel; F. Taylor; R. K. Yamamoto; H. Kim; S. E. McLachlin; P. M. Patel; S. H. Robertson; A. Lazzaro; V. Lombardo; F. Palombo; J. M. Bauer; L. Cremaldi; V. Eschenburg; R. Godang; R. Kroeger; D. A. Sanders; D. J. Summers; H. W. Zhao; S. Brunet; D. Côté; M. Simard; P. Taras; F. B. Viaud; H. Nicholson; N. Cavallo; G. de Nardo; F. Fabozzi; C. Gatto; L. Lista; D. Monorchio; P. Paolucci; D. Piccolo; C. Sciacca; M. A. Baak; G. Raven; H. L. Snoek; C. P. Jessop; J. M. Losecco; G. Benelli; L. A. Corwin; K. K. Gan; K. Honscheid; D. Hufnagel; H. Kagan; R. Kass; J. P. Morris; A. M. Rahimi; J. J. Regensburger; R. Ter-Antonyan; Q. K. Wong; N. L. Blount; J. Brau; R. Frey; O. Igonkina; J. A. Kolb; M. Lu; R. Rahmat; N. B. Sinev; D. Strom; J. Strube; E. Torrence; A. Gaz; M. Margoni; M. Morandin; A. Pompili; M. Posocco; M. Rotondo; F. Simonetto; R. Stroili; C. Voci; E. Ben-Haim

2007-01-01

48

K* resonance effects on direct CP violation in B{yields}{pi}{pi}K  

SciTech Connect

B{sup {+-}{yields}{pi}+{pi}-}K{sup {+-}}and B{sup 0{yields}{pi}+{pi}-}K{sup 0} decay channels are analyzed within the QCD factorization scheme where final state interactions before and after hadronization are included. The K*(892) and K{sub 0}*(1430) resonance effects are taken into account using the presently known {pi}K strange vector and scalar form factors. The weak decay amplitudes, which are calculated at leading power in {Lambda}{sub QCD}/m{sub b} and at the next-to-leading order in the strong coupling constant, include the hard-scattering and annihilation contributions. The end-point divergences of these weak final state interactions are controlled by two complex parameters determined through a fit to the available effective mass and helicity angle distribution, CP asymmetry, and K*(892) branching ratio data. The predicted K{sub 0}*(1430) branching ratios and the calculated direct CP violation asymmetries are compared to the Belle and BABAR Collaboration data.

Leitner, O.; Dedonder, J.-P.; Loiseau, B. [Laboratoire de Physique Nucleaire et de Hautes Energies (IN2P3-CNRS-Universites Paris 6 et 7), Groupe Theorie, Universites Pierre et Marie Curie et Paris-Diderot, 4 place Jussieu, 75252 Paris (France); Kaminski, R. [Division of Theoretical Physics, Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, 31-342 Krakow (Poland)

2010-05-01

49

Stacking interactions in PUF?RNA complexes  

SciTech Connect

Stacking interactions between amino acids and bases are common in RNA-protein interactions. Many proteins that regulate mRNAs interact with single-stranded RNA elements in the 3' UTR (3'-untranslated region) of their targets. PUF proteins are exemplary. Here we focus on complexes formed between a Caenorhabditis elegans PUF protein, FBF, and its cognate RNAs. Stacking interactions are particularly prominent and involve every RNA base in the recognition element. To assess the contribution of stacking interactions to formation of the RNA-protein complex, we combine in vivo selection experiments with site-directed mutagenesis, biochemistry, and structural analysis. Our results reveal that the identities of stacking amino acids in FBF affect both the affinity and specificity of the RNA-protein interaction. Substitutions in amino acid side chains can restrict or broaden RNA specificity. We conclude that the identities of stacking residues are important in achieving the natural specificities of PUF proteins. Similarly, in PUF proteins engineered to bind new RNA sequences, the identity of stacking residues may contribute to 'target' versus 'off-target' interactions, and thus be an important consideration in the design of proteins with new specificities.

Yiling Koh, Yvonne; Wang, Yeming; Qiu, Chen; Opperman, Laura; Gross, Leah; Tanaka Hall, Traci M.; Wickens, Marvin (NIH); (UW)

2012-07-02

50

{epsilon}{prime} and the decay {eta}{r_arrow}{pi}{pi} in a theory with both explicit and spontaneous {ital CP} violation  

SciTech Connect

In an extended version of the standard model, containing three Higgs doublets but with a {ital CP}-invariant strong interaction sector, there are two sources of {ital CP} violation. For the parameter {epsilon}{prime}, of the {ital K}{r_arrow}{pi}{pi} system, such a theory allows any value less than or equal to its present experimental mean value. If the present experimental magnitude of {epsilon}{prime} is used one obtains that the rate for the {ital CP}-violating decay {eta}{r_arrow}{pi}{pi} is 10{sup 12} times larger than the corresponding rate in a theory without spontaneous {ital CP} violation. Our estimates also yield that the upper limit on the rate of {eta}{r_arrow}{pi}{pi} in such a theory is about a factor of 16 larger than the corresponding present upper limit obtained in a theory where {ital CP} is violated in strong interactions due to the {theta} term.

Jarlskog, C.; Shabalin, E. [Department of Mathematical Physics, LTH, Lund University, Box 118, S-22100 Lund (Sweden)] [Department of Mathematical Physics, LTH, Lund University, Box 118, S-22100 Lund (Sweden)

1995-12-01

51

Observation of the decay KS-->pi+pi- e+e-  

Microsoft Academic Search

We present the first observation of the decay KS-->pi+pi-e+e- based upon the data collected in 1998 by the NA48 experiment at CERN. We have identified a clean sample of 56 events with negligible background contamination. Using KL-->pi+pi- pi0D decays as normalization sample, the branching ratio is measured to be BR(KS-->pi+pi- e+e-)=[4.5+\\/-0.7(stat)+\\/- 0.4(syst)]×10-5. This result is in good agreement with the

A. Lai; D. Marras; L. Musa; A. Bevan; R. S. Dosanjh; T. J. Gershon; B. Hay; G. E. Kalmus; D. J. Munday; M. D. Needham; E. Olaiya; M. A. Parker; T. O. White; S. A. Wotton; G. Barr; H. Blümer; G. Bocquet; A. Ceccucci; D. Cundy; G. D'Agostini; N. Doble; V. Falaleev; L. Gatignon; A. Gonidec; G. Govi; P. Grafström; W. Kubischta; A. Lacourt; A. Norton; S. Palestini; B. Panzer-Steindel; B. Peyaud; H. Taureg; M. Velasco; H. Wahl; C. Cheshkov; P. Hristov; V. Kekelidze; D. Madigojine; A. Mestvirishvili; N. Molokanova; Yu. Potrebenikov; G. Tatishvili; A. Tkatchev; A. Zinchenko; I. Knowles; V. Martin; H. Parsons; R. Sacco; C. Lazzeroni; A. Walker; M. Contalbrigo; P. Dalpiaz; J. Duclos; P. L. Frabetti; A. Gianoli; M. Martini; F. Petrucci; M. Savrié; A. Bizzeti; M. Calvetti; G. Collazuol; G. Graziani; E. Iacopini; M. Lenti; H. G. Becker; M. Eppard; H. Fox; K. Holtz; A. Kalter; K. Kleinknecht; U. Koch; L. Köpke; I. Pellmann; A. Peters; B. Renk; S. A. Schmidt; V. Schönharting; Y. Schué; A. Winhart; M. Wittgen; J. C. Chollet; S. Crépé; L. Fayard; L. Iconomidou-Fayard; J. Ocariz; G. Unal; I. Wingerter-Seez; G. Anzivino; P. Cenci; E. Imbergamo; P. Lubrano; A. Nappi; M. Pepe; M. Piccini; R. Carosi; R. Casali; C. Cerri; M. Cirilli; F. Costantini; R. Fantechi; S. Giudici; B. Gorini; I. Mannelli; G. Pierazzini; M. Sozzi; J. B. Cheze; J. Cogan; M. De Beer; P. Debu; A. Formica; R. Granier de Cassagnac; E. Mazzucato; R. Turlay; B. Vallage; I. Augustin; M. Bender; M. Holder; M. Ziolkowski; R. Arcidiacono; C. Biino; F. Marchetto; E. Menichetti; N. Pastrone; J. Nassalski; E. Rondio; M. Szleper; W. Wislicki; S. Wronka; H. Dibon; G. Fischer; M. Jeitler; M. Markytan; I. Mikulec; G. Neuhofer; M. Pernicka; A. Taurok

2000-01-01

52

Highly congested nondistorted diheteroarylnaphthalenes: model compounds for the investigation of intramolecular pi-stacking interactions.  

PubMed

[structure: see text] The rigid, highly congested structure of 1,8-diacridylnaphthalenes has been studied in solution and in the solid state. The unique geometry of these compounds forces the acridyl rings to undergo face-to-face interactions while rendering T-shaped orientations and face-to-edge interactions impossible. Crystallographic analysis shows that splaying between the heteroaryl rings decreases while twisting between the cofacial rings increases as the acridyl nitrogens of the 1,8-diacridylnaphthalene framework are subsequently oxidized. The peri-acridyl rings are slightly splayed but remain perfectly planar in all cases. The significant decrease in splaying indicates enhanced pi-pi-attraction between the electron-rich acridyl N-oxide moieties, which is in agreement with recently reported symmetry-adapted perturbation theory calculations. The pi-stacking and the molecular geometry between the acridyl rings observed in the solid state have been confirmed through in-solution studies showing characteristic proton NMR upfield shifts and optical properties indicative of static intramolecular arene-arene interactions. Acridyl protons located directly above the adjacent aryl moiety as a consequence of twisting between the heteroaryl rings were identified by COSY NMR measurements and found to intrude into the pi-cloud and diamagnetic ring current of the neighboring acridine. Different shapes and strong red shifts of the fluorescence emission maxima of the diacridylnaphthalenes in comparison to parental acridyl monomers have been attributed to static excimer emission. PMID:15760218

Mei, Xuefeng; Wolf, Christian

2005-03-18

53

Photoproduction of pi+pi-pi0 on hydrogen with linearly polarized photons of energy 20-70 GeV  

Microsoft Academic Search

Results on photoproduction of pi+pi-pi0 in the photon energy range 20-70 GeV are presented. For the omega meson, the production cross-section is found to be 1010+\\/-15 (statistical)+\\/-290 (systematic) nb and is constant over the incident photon energy range. Spin-density matrix elements are evaluated for omega meson production. The phi meson is observed with a total photoproduction cross section (corrected for

M. Atkinson; T. J. Axon; D. Barberis; T. J. Brodbeck; G. R. Brookes; J. J. Bunn; P. J. Bussey; A. B. Clegg; J. B. Dainton; M. Davenport; B. Dickinson; B. Diekmann; A. Donnachie; R. J. Ellison; P. Flower; P. J. Flynn; W. Galbraith; K. Heinloth; R. C. W. Henderson; R. E. Hughes-Jones; J. S. Hutton; M. Ibbotson; H. P. Jakob; M. Jung; M. A. R. Kemp; B. R. Kumar; J. Laberrigue; G. D. Lafferty; J. C. Lassalle; J. M. Lévy; V. Liebenau; R. H. McClatchey; D. Mercer; J. A. G. Morris; J. V. Morris; D. Newton; C. Paterson; G. N. Patrick; E. Paul; C. Raine; M. Reidenbach; H. Rotscheidt; A. Schlösser; P. H. Sharp; I. O. Skillicorn; K. M. Smith; K. M. Storr; R. J. Thompson; Ch. de La Vaissière; A. P. Waite; M. F. Worsell; T. P. Yiou

1984-01-01

54

Measurement of chicJ decays to 2(pi+pi-)pp¯ final states  

Microsoft Academic Search

Using chicJ-->2(pi+pi-)pp¯ decays from 14×106psi(2S) events accumulated by the BESII detector at the BEPC, the intermediate states Xi-Xi¯+, LambdaLambda¯pi+pi-, and KS0KS0pp¯ are studied, and their branching ratios or upper limits are measured.

M. Ablikim; J. Z. Bai; Y. Ban; J. G. Bian; X. Cai; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; Y. S. Dai; L. Y. Diao; Z. Y. Deng; Q. F. Dong; S. X. Du; J. Fang; S. S. Fang; C. D. Fu; C. S. Gao; Y. N. Gao; S. D. Gu; Y. T. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; M. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. T. Huang; X. B. Ji; X. S. Jiang; X. Y. Jiang; J. B. Jiao; D. P. Jin; S. Jin; Yi Jin; Y. F. Lai; G. Li; H. B. Li; H. H. Li; J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; X. N. Li; X. Q. Li; Y. L. Li; Y. F. Liang; H. B. Liao; B. J. Liu; C. X. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. B. Liu; J. P. Liu; Q. Liu; R. G. Liu; Z. A. Liu; Y. C. Lou; F. Lu; G. R. Lu; J. G. Lu; C. L. Luo; F. C. Ma; H. L. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; Z. P. Mao; X. H. Mo; J. Nie; S. L. Olsen; H. P. Peng; R. G. Ping; N. D. Qi; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; C. P. Shen; D. L. Shen; X. Y. Shen; H. Y. Sheng; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; Z. Q. Tan; X. Tang; G. L. Tong; G. S. Varner; D. Y. Wang; L. L. Wang; L. S. Wang; M. Wang; P. L. Wang; W. F. Wang; Y. F. Wang; Z. Y. Wang; Zheng Wang; C. L. Wei; D. H. Wei; N. Wu; X. M. Xia; X. X. Xie; G. F. Xu; X. P. Xu; Y. Xu; M. L. Yan; H. X. Yang; Y. X. Yang; M. H. Ye; Y. X. Ye; Z. Y. Yi; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Q. Zhang; H. Y. Zhang; J. W. Zhang; J. Y. Zhang; S. H. Zhang; X. M. Zhang; X. Y. Zhang; Yiyun Zhang; Z. P. Zhang; D. X. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; Z. P. Zheng; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2006-01-01

55

Exclusive production of pp¯pi+pi- in photon-photon collisions  

Microsoft Academic Search

We report a measurement of the e+e--->e+e-pp¯pi+pi- process with the TPC\\/Two-Gamma facility at the PEP e+e- storage ring at SLAC. Forty-five pp¯pi+pi- events were identified in data corresponding to an integrated e+e- luminosity of 142 pb-1. The cross section for gammagamma-->pp¯pi+pi- is given both as a function of the gammagamma center-of-mass energy Wgammagamma, with Wgammagamma between 2.5 and 5.5 GeV,

H. Aiha

1989-01-01

56

High statistics study of the f0(980) resonance in gammagamma-->pi+pi- production  

Microsoft Academic Search

We report on a high statistics measurement of the cross section of the process gammagamma-->pi+pi- in the pi+pi- invariant mass range 0.8GeV\\/c2pi+pi- and two-photon decay widths of

T. Mori; S. Uehara; Y. Watanabe; K. Abe; I. Adachi; H. Aihara; D. Anipko; K. Arinstein; V. Aulchenko; A. M. Bakich; E. Barberio; A. Bay; I. Bedny; K. Belous; U. Bitenc; I. Bizjak; A. Bondar; A. Bozek; M. Bracko; J. Brodzicka; T. E. Browder; M.-C. Chang; P. Chang; A. Chen; W. T. Chen; B. G. Cheon; R. Chistov; Y. Choi; J. Dalseno; M. Dash; S. Eidelman; D. Epifanov; S. Fratina; N. Gabyshev; T. Gershon; B. Golob; H. Ha; K. Hayasaka; H. Hayashii; M. Hazumi; D. Heffernan; T. Hokuue; Y. Hoshi; S. Hou; W.-S. Hou; T. Iijima; K. Ikado; A. Imoto; K. Inami; A. Ishikawa; R. Itoh; M. Iwasaki; Y. Iwasaki; H. Kaji; J. H. Kang; H. Kawai; T. Kawasaki; H. R. Khan; A. Kibayashi; H. Kichimi; Y. J. Kim; S. Korpar; P. Krizan; P. Krokovny; R. Kulasiri; R. Kumar; A. Kuzmin; Y.-J. Kwon; M. J. Lee; S. E. Lee; T. Lesiak; A. Limosani; S.-W. Lin; D. Liventsev; J. MacNaughton; G. Majumder; F. Mandl; T. Matsumoto; H. Miyake; H. Miyata; Y. Miyazaki; R. Mizuk; G. R. Moloney; Y. Nagasaka; M. Nakao; H. Nakazawa; Z. Natkaniec; S. Nishida; O. Nitoh; S. Noguchi; S. Ogawa; T. Ohshima; S. Okuno; S. L. Olsen; S. Ono; Y. Onuki; H. Ozaki; P. Pakhlov; G. Pakhlova; K. S. Park; L. S. Peak; R. Pestotnik; L. E. Piilonen; A. Poluektov; H. Sahoo; Y. Sakai; N. Satoyama; T. Schietinger; O. Schneider; R. Seidl; K. Senyo; M. E. Sevior; M. Shapkin; H. Shibuya; B. Shwartz; J. B. Singh; A. Sokolov; A. Somov; N. Soni; S. Stanic; M. Staric; H. Stoeck; T. Sumiyoshi; F. Takasaki; K. Tamai; M. Tanaka; G. N. Taylor; Y. Teramoto; X. C. Tian; I. Tikhomirov; T. Tsuboyama; T. Tsukamoto; T. Uglov; S. Uno; P. Urquijo; Y. Usov; G. Varner; S. Villa; C. C. Wang; E. Won; Q. L. Xie; B. D. Yabsley; A. Yamaguchi; Y. Yamashita; M. Yamauchi; C. C. Zhang; Z. P. Zhang; V. Zhilich; V. Zhulanov; A. Zupanc

2007-01-01

57

Measurement of the branching fraction for D+-->K-pi+pi+  

Microsoft Academic Search

Using the CLEO II detector at the Cornell Electron Storage Ring we have measured the ratio of branching fractions, B(D+-->K-pi+pi+)\\/(D0-->K-pi+)=2.35+\\/-0.16+\\/-0.16. Our recent measurement of scrB(D0-->K-pi+) then gives scrB(D+-->K-pi+pi+)=(9.3+\\/-0.6+\\/-0.8)%.

R. Balest; K. Cho; M. Daoudi; W. T. Ford; D. R. Johnson; K. Lingel; M. Lohner; P. Rankin; J. G. Smith; J. P. Alexander; C. Bebek; K. Berkelman; K. Bloom; T. E. Browder; D. G. Cassel; H. A. Cho; D. M. Coffman; P. S. Drell; R. Ehrlich; P. Gaiderev; M. Garcia-Sciveres; B. Geiser; B. Gittelman; S. W. Gray; D. L. Hartill; B. K. Heltsley; C. D. Jones; S. L. Jones; J. Kandaswamy; N. Katayama; P. C. Kim; D. L. Kreinick; G. S. Ludwig; J. Masui; J. Mevissen; N. B. Mistry; C. R. Ng; E. Nordberg; J. R. Patterson; D. Peterson; D. Riley; S. Salman; M. Sapper; F. Würthwein; P. Avery; A. Freyberger; J. Rodriguez; R. Stephens; S. Yang; J. Yelton; D. Cinabro; S. Henderson; T. Liu; M. Saulnier; R. Wilson; H. Yamamoto; T. Bergfeld; B. I. Eisenstein; G. Gollin; B. Ong; M. Palmer; M. Selen; J. J. Thaler; A. J. Sadoff; R. Ammar; S. Ball; P. Baringer; A. Bean; D. Besson; D. Coppage; N. Copty; R. Davis; N. Hancock; M. Kelly; N. Kwak; H. Lam; Y. Kubota; M. Lattery; J. K. Nelson; S. Patton; D. Perticone; R. Poling; V. Savinov; S. Schrenk; R. Wang; M. S. Alam; I. J. Kim; B. Nemati; J. J. O'neill; H. Severini; C. R. Sun; M. M. Zoeller; G. Crawford; C. M. Daubenmier; R. Fulton; D. Fujino; K. K. Gan; K. Honscheid; H. Kagan; R. Kass; J. Lee; R. Malchow; Y. Skovpen; M. Sung; C. White; F. Butler; X. Fu; G. Kalbfleisch; W. R. Ross; P. Skubic; J. Snow; P. L. Wang; M. Wood; D. N. Brown; J. Fast; R. L. McIlwain; T. Miao; D. H. Miller; M. Modesitt; D. Payne; E. I. Shibata; I. P. Shipsey; P. N. Wang; M. Battle; J. Ernst; Y. Kwon; S. Roberts; E. H. Thorndike; C. H. Wang; J. Dominick; M. Lambrecht; S. Sanghera; V. Shelkov; T. Skwarnicki; R. Stroynowski; I. Volobouev; G. Wei; P. Zadorozhny; M. Artuso; M. Goldberg; D. He; N. Horwitz; R. Kennett; G. C. Moneti; F. Muheim; Y. Mukhin; S. Playfer; Y. Rozen; S. Stone; M. Thulasidas; G. Vasseur; G. Zhu; J. Bartelt; S. E. Csorna; Z. Egyed; V. Jain; K. Kinoshita; K. W. Edwards; M. Ogg; D. I. Britton; E. R. Hyatt; D. B. Macfarlane; P. M. Patel; D. S. Akerib; B. Barish; M. Chadha; S. Chan; D. F. Cowen; G. Eigen; J. S. Miller; C. O'grady; J. Urheim; A. J. Weinstein; D. Acosta; M. Athanas; G. Masek; H. P. Paar; J. Gronberg; R. Kutschke; S. Menary; R. J. Morrison; S. Nakanishi; H. N. Nelson; T. K. Nelson; C. Qiao; J. D. Richman; A. Ryd; H. Tajima; D. Sperka; M. S. Witherell; M. Procario

1994-01-01

58

Stacking interactions between adenines in oxidized oligonucleotides.  

PubMed

The effects of stacking interactions on the oxidation potentials of single strand oligonucleotides containing up to four consecutive adenines, alternated with thymines and cytosines in different sequences and ratios, have been determined by means of differential pulse voltammetry. Voltammetric measurements point toward the establishment in solution of structured oligonucleotide conformations, in which the nucleobases are well stacked altogether. Molecular dynamics simulations confirm that finding, indicating that single strands assume geometrical parameters characteristic of the B-DNA form. The analysis of the voltammetric signals in terms of a simple effective tight binding quantum model leads one to infer a robust set of parameters for treating hole transfer in one-electron-oxidized DNA containing adenines and thymines. PMID:23837863

Capobianco, Amedeo; Caruso, Tonino; Celentano, Maurizio; D'Ursi, Anna Maria; Scrima, Mario; Peluso, Andrea

2013-08-01

59

Production of $\\\\sigma$ in $\\\\psi(2S)\\\\to \\\\pi^{+}\\\\pi^{-}J\\/\\\\psi$  

Microsoft Academic Search

Using 14M $\\\\psi(2S)$ events accumulated by BESII at the BEPC, a Covariant\\u000aHelicity Amplitude Analysis is performed for $\\\\psi(2S)\\\\to\\\\pi^+\\\\pi^-J\\/\\\\psi,\\u000aJ\\/\\\\psi\\\\to \\\\mu^+\\\\mu^-$. The $\\\\pi^+\\\\pi^-$ mass spectrum, distinctly different\\u000afrom phase space, suggests $\\\\sigma$ production in this process. Two different\\u000atheoretical schemes are used in the global fit to the data. The results are\\u000aconsistent with the existence of the $\\\\sigma$. The

J. Z. Bai; Y. Ban; X. Cai; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Jin Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; Y. S. Dai; L. Y. Diao; Z. Y. Deng; Q. F. Dong; J. Fang; S. S. Fang; C. D. Fu; C. S. Gao; Y. N. Gao; S. D. Gu; Y. T. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; M. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. T. Huang; X. B. Ji; X. S. Jiang; X. Y. Jiang; J. B. Jiao; D. P. Jin; S. Jin; Yi Jin; Y. F. Lai; G. Li; H. B. Li; H. H. Li; J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; X. N. Li; X. Q. Li; Y. L. Li; Y. F. Liang; H. B. Liao; B. J. Liu; C. X. Liu; F. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. Liu; J. B. Liu; Q. Liu; R. G. Liu; Z. A. Liu; Y. C. Lou; F. Lu; G. R. Lu; J. G. Lu; C. L. Luo; F. C. Ma; H. L. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; Z. P. Mao; X. H. Mo; J. Nie; S. L. Olsen; H. P. Peng; R. G. Ping; N. D. Qi; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; C. P. Shen; D. L. Shen; X. Y. Shen; H. Y. Sheng; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; Z. Q. Tan; X. Tang; G. L. Tong; G. S. Varner; D. Y. Wang; L. Wang; L. S. Wang; M. Wang; P. Wang; W. F. Wang; Y. F. Wang; Z. Wang; Zheng Wang; C. L. Wei; D. H. Wei; N. Wu; X. M. Xia; X. X. Xie; G. F. Xu; X. P. Xu; Y. Xu; M. L. Yan; H. X. Yang; Y. X. Yang; M. H. Ye; Y. X. Ye; Z. Y. Yi; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Q. Zhang; H. Y. Zhang; J. W. Zhang; J. Y. Zhang; S. H. Zhang; X. M. Zhang; X. Y. Zhang; Yiyun Zhang; Z. P. Zhang; D. X. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; Z. P. Zheng; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2006-01-01

60

Radiative Kaon Decays and a Determination of the {pi}{pi} Scattering Length  

SciTech Connect

In this paper results are presented for radiative KL decays from the KTeV experiment. Also presented is a determination of the {pi}{pi} scattering length from the NA48 collaboration using the decay K{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup 0}{pi}{sup 0}.

Corcoran, M. D. [Rice University, Houston, TX (United States)

2006-11-17

61

I=2 pi-pi Scattering from Fully-Dynamical Mixed-Action Lattice QCD  

SciTech Connect

We compute the I=2 {pi}{pi} scattering length at pion masses of m{sub {pi}} = 294, 348 and 484 MeV in fully-dynamical lattice QCD using Luescher's finite-volume method. The calculation is performed with domain-wall valence-quark propagators on asqtad-improved MILC configurations with staggered sea quarks. Chiral perturbation theory is used to perform the extrapolation of the scattering length from lattice quark masses down to the physical value, and we find m{sub {pi}}a{sub 2} = -0.0426 {+-} 0.0006 {+-} 0.0003 {+-} 0.0018, in good agreement with experiment. The I = 2 {pi}{pi} scattering phase shift is calculated to be {delta} = -43 {+-} 10 {+-} 5 degrees at |p| {approx} 544 MeV for m{pi} {approx} 484 MeV.

Silas R. Beane; Paulo F. Bedaque; Kostas Orginos; Martin J. Savage

2005-06-11

62

Structure functions in the decay tau-\\/+-->pi-\\/+pi0pi0nutau  

Microsoft Academic Search

Using the CLEO II detector operating at the Cornell Electron Storage Ring (CESR) e+e- collider, we have measured the structure functions in the decay tau-\\/+-->pi-\\/+pi0pi0nutau, based on a sample corresponding to 4×106 produced tau-pair events. We determine the integrated structure functions, which depend only on the three pion invariant mass, as well as the structure functions differential in the Dalitz

T. E. Browder; Y. Li; J. L. Rodriguez; H. Yamamoto; T. Bergfeld; B. I. Eisenstein; J. Ernst; G. E. Gladding; G. D. Gollin; R. M. Hans; E. Johnson; I. Karliner; M. A. Marsh; M. Palmer; C. Plager; C. Sedlack; M. Selen; J. J. Thaler; J. Williams; K. W. Edwards; R. Janicek; P. M. Patel; A. J. Sadoff; R. Ammar; P. Baringer; A. Bean; D. Besson; R. Davis; S. Kotov; I. Kravchenko; N. Kwak; X. Zhao; S. Anderson; V. V. Frolov; Y. Kubota; S. J. Lee; R. Mahapatra; J. J. O'neill; R. Poling; T. Riehle; A. Smith; S. Ahmed; M. S. Alam; S. B. Athar; L. Jian; L. Ling; A. H. Mahmood; M. Saleem; S. Timm; F. Wappler; A. Anastassov; J. E. Duboscq; K. K. Gan; C. Gwon; T. Hart; K. Honscheid; H. Kagan; R. Kass; J. Lorenc; H. Schwarthoff; E. von Toerne; M. M. Zoeller; S. J. Richichi; H. Severini; P. Skubic; A. Undrus; M. Bishai; S. Chen; J. Fast; J. W. Hinson; J. Lee; N. Menon; D. H. Miller; E. I. Shibata; I. P. Shipsey; Y. Kwon; A. L. Lyon; E. H. Thorndike; C. P. Jessop; K. Lingel; H. Marsiske; M. L. Perl; V. Savinov; D. Ugolini; X. Zhou; T. E. Coan; V. Fadeyev; I. Korolkov; Y. Maravin; I. Narsky; R. Stroynowski; J. Ye; T. Wlodek; M. Artuso; R. Ayad; E. Dambasuren; S. Kopp; G. Majumder; G. C. Moneti; S. Schuh; T. Skwarnicki; S. Stone; A. Titov; G. Viehhauser; J. C. Wang; A. Wolf; J. Wu; S. E. Csorna; K. W. McLean; S. Marka; Z. Xu; R. Godang; K. Kinoshita; I. C. Lai; P. Pomianowski; S. Schrenk; G. Bonvicini; D. Cinabro; R. Greene; L. P. Perera; G. J. Zhou; S. Chan; G. Eigen; E. Lipeles; M. Schmidtler; A. Shapiro; W. M. Sun; J. Urheim; A. J. Weinstein; F. Würthwein; D. E. Jaffe; G. Masek; H. P. Paar; E. M. Potter; S. Prell; V. Sharma; D. M. Asner; A. Eppich; J. Gronberg; T. S. Hill; D. J. Lange; R. J. Morrison; T. K. Nelson; J. D. Richman; R. A. Briere; B. H. Behrens; W. T. Ford; A. Gritsan; H. Krieg; J. Roy; J. G. Smith; J. P. Alexander; R. Baker; C. Bebek; B. E. Berger; K. Berkelman; F. Blanc; V. Boisvert; D. G. Cassel; M. Dickson; P. S. Drell; K. M. Ecklund; R. Ehrlich; A. D. Foland; P. Gaidarev; R. S. Galik; L. Gibbons; B. Gittelman; S. W. Gray; D. L. Hartill; B. K. Heltsley; P. I. Hopman; C. D. Jones; D. L. Kreinick; T. Lee; Y. Liu; T. O. Meyer; N. B. Mistry; C. R. Ng; E. Nordberg; J. R. Patterson; D. Peterson; D. Riley; J. G. Thayer; P. G. Thies; B. Valant-Spaight; A. Warburton; P. Avery; M. Lohner; C. Prescott; A. I. Rubiera; J. Yelton; J. Zheng; G. Brandenburg; A. Ershov; Y. S. Gao; D. Y.-J. Kim; R. Wilson

2000-01-01

63

Observation of CP violation in B(0) --> K(+)pi(-) and B(0) --> pi(+)pi(-).  

PubMed

We report observations of CP violation in the decays B(0) --> K(+)pi(-) and B(0) --> pi(+)pi(-) in a sample of 383 x 10(6) Upsilon(4S) --> BB[over] events. We find 4372+/-82 B(0) --> K(+)pi(-) decays and measure the direct CP-violating charge asymmetry A(Kpi) = -0.107+/-0.018(stat)(-0.004)(+0.007)(syst), which excludes the CP-conserving hypothesis with a significance of 5.5 standard deviations. In the same sample, we find 1139+/-49 B(0) --> pi(+)pi(-) decays and measure the CP-violating asymmetries S(pipi) = -0.60+/-0.11(stat)+/-0.03(syst) and C(pipi) = -0.21+/-0.09(stat)+/-0.02(syst). CP conservation in B(0) --> pi(+)pi(-) (S(pipi) = C(pipi) = 0) is excluded at a confidence level 1-C.L. = 8 x 10(-8), corresponding to 5.4 standard deviations. PMID:17678212

Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Eigen, G; Ofte, I; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Tackmann, K; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Williams, D C; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Fisher, P H; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F

2007-07-13

64

Theoretical calculations of base-base interactions in nucleic acids: I. Stacking interactions in free bases.  

PubMed Central

Stacking interactions in free bases were computed on the basis of molecular association. The results of the calculations were compared with the stacking patterns observed in a few single crystals of nucleic acid components as examples. The following are the conclusions: (i) there can be two types of stacking pattern classified as normal and inverted types for any two interacting bases and both can be energetically favourable (ii) in both the types the stacking interaction is a combined effect of the overlap of the interacting bases and relative positions and orientations of the atomic centres of the two bases (iii) crystal symmetry and H-bonding interaction may influence stacking patterns.

Gupta, G; Sasisekharan, V

1978-01-01

65

Multidimensional frameworks assembled from silver(I) coordination polymers containing flexible bis(thioquinolyl) ligands: role of the intra- and intermolecular aromatic stacking interactions.  

PubMed

The two flexible multidentate ligands 1,3-bis(8-thioquinolyl)propane (C3TQ) and 1,4-bis(8-thioquinolyl)butane (C4TQ) were reacted with AgX (X = CF(3)SO(3)(-) or ClO(4)(-)) to give four new complexes: ([Ag(C3TQ)](ClO(4)))(n)() 1, ([Ag(C3TQ)](CF(3)SO(3)))(n)() 2, ([Ag(2)(C4TQ)(CF(3)SO(3))(CH(3)CN)](CF(3)SO(3)))(n)() 3, and ([Ag(C4TQ)](ClO(4)))(n)() 4. All complexes have been characterized by elemental analysis, IR, and (1)H NMR spectroscopy. Single-crystal X-ray analysis showed that chain structures form for all complexes in which the quinoline rings interact via various intra- (1) or intermolecular (2, 3, and 4) pi-pi aromatic stacking interactions, which in the latter cases results in multidimensional structures. Additional weak interactions, such as Ag.O and Ag.S contacts and C-H.O hydrogen bonding, are also present and help form stable, crystalline materials. It was found that the (CH(2))(n) spacers (n = 3 or 4) affect the orientation of the two terminal quinolyl rings, thereby significantly influencing the specific framework structure that forms. If the same ligand is used, on the other hand, then the different counteranions have the greatest effect on the final structure. PMID:12793810

Chen, Chun-Long; Su, Cheng-Yong; Cai, Yue-Peng; Zhang, Hua-Xin; Xu, An-Wu; Kang, Bei-Sheng; Zur Loye, Hans-Conrad

2003-06-16

66

Enhanced face-to-face Pi stacking in perfluoroalkylated organic semiconductor materials: Crystallographic and NMR studies of weak non-covalent interactions in condensed phases  

NASA Astrophysics Data System (ADS)

In this chapter, the synthesis of new perfluoroalkylated hydrocarbon aromatics A) 1,2,4,5-tetrakis(nonafluorobutyl)-benzene (4-C4F 9-Bz), B) 1,3,6,8-tetrakis(nonafluorobutyl)-pyrene (4-C4F 9-pyrene) and two new heteroaromatic compounds C) 3,8-bis(nonafluorobutyl)-1,10-phenanthroline(2-C4F9-1,10-phen) and D) 4,4'-bis(nonafluorobutyl)-2,2'-bipyridine (2-C4F9-bipy) were described, using copper mediated perfluoroalkylation in a mixture of DMSO(anhy) and anhydrous benzotrifluoride (BTF(anhy)). All the compounds were purified by recrystallization and characterized by 1H NMR, 19F NMR, mass spectrometry and elemental analyses. Single-crystals were obtained for these novel compounds and their packing modes are studied and compared with other literature reporting single crystal structures to study the effects of substitution of electron deficient fluoroalkyl chains on aromatics on packing modes, and weak noncovalent interactions that became the basis for the present chapter. We found that by fine-tuning the size of the aromatic core, lengthening perfluoroalkyl chain, altering the substitution position, and making use of these weak fluorous interactions, 1-D pi-pi stacking in these model compounds is achieved. This can provide us an opportunity to extend this concept to n-type solution processable air-stable organic semiconductor molecules which can be used in real world applications.

Tottempudi, Usha Kiran

67

Edge-edge interactions in stacked graphene nanoplatelets  

SciTech Connect

High-resolution transmission electron microscopy (HRTEM) studies show the dynamics of small graphene platelets on larger graphene layers. The platelets move nearly freely to eventually lock in at well-defined positions close to the edges of the larger underlying graphene sheet. While such movement is driven by a shallow potential energy surface described by an interplane interaction, the lock-in position occurs by via edge-edge interactions of the platelet and the graphene surface located underneath. Here we quantitatively study this behavior using van der Waals density functional calculations. Local interactions at the open edges are found to dictate stacking configurations that are different from Bernal (AB) stacking. These stacking configurations are known to be otherwise absent in edge-free two-dimensional (2D) graphene. The results explain the experimentally observed platelet dynamics and provide a detailed account of the new electronic properties of these combined systems.

Cruz Silva, Eduardo [ORNL; Terrones Maldonado, Humberto [ORNL; Terrones Maldonado, Mauricio [ORNL; Jia, Xiaoting [Massachusetts Institute of Technology (MIT); Sumpter, Bobby G [ORNL; Dresselhaus, M [Massachusetts Institute of Technology (MIT); Meunier, V. [Rensselaer Polytechnic Institute (RPI)

2013-01-01

68

Resonances in $J\\/\\\\psi \\\\to \\\\phi \\\\pi ^+\\\\pi ^-$ and $\\\\phi K^+K^-$  

Microsoft Academic Search

A partial wave analysis is presented of $J\\/\\\\psi \\\\to \\\\phi \\\\pi ^+\\\\pi ^-$ and\\u000a$\\\\phi K^+K^-$ from a sample of 58M $J\\/\\\\psi$ events in the BES II detector. The\\u000a$f_0(980)$ is observed clearly in both sets of data, and parameters of the\\u000aFlatt\\\\' e formula are determined accurately: $M = 965 \\\\pm 8$ (stat) $\\\\pm 6$\\u000a(syst) MeV\\/c$^2$, $g_1 =

M. Ablikim; J. Z. Bai; Y. Ban; J. G. Bian; D. V. Bugg; X. Cai; J. F. Chang; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Jin Chen; Jun Chen; M. L. Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; H. L. Dai; Y. S. Dai; Z. Y. Deng; L. Y. Dong; Q. F. Dong; Z. Z. Du; J. Fang; S. S. Fang; C. D. Fu; H. Y. Fu; C. S. Gao; Y. N. Gao; M. Y. Gong; W. X. Gong; S. D. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. P. Huang; X. T. Huang; X. B. Ji; C. H. Jiang; X. S. Jiang; D. P. Jin; S. Jin; Y. Jin; Y. F. Lai; F. Li; G. Li; H. H. Li; J. Li; Q. J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; Y. L. Li; Y. F. Liang; H. B. Liao; C. X. Liu; F. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. Liu; J. B. Liu; R. G. Liu; Z. A. Liu; Z. X. Liu; F. Lu; G. R. Lu; H. J. Lu; J. G. Lu; C. L. Luo; L. X. Luo; X. L. Luo; F. C. Ma; H. L. Ma; J. M. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; X. Y. Ma; Z. P. Mao; X. H. Mo; J. Nie; Z. D. Nie; S. L. Olsen; H. P. Peng; N. D. Qi; C. D. Qian; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; D. L. Shen; X. Y. Shen; H. Y. Sheng; F. Shi; X. Shi; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; X. Tang; N. Tao; Y. R. Tian; G. L. Tong; G. S. Varner; D. Y. Wang; J. Z. Wang; K. Wang; L. Wang; M. Wang; P. Wang; S. Z. Wang; W. F. Wang; Y. F. Wang; Z. Wang; Zheng Wang; C. L. Wei; D. H. Wei; Y. M. Wu; X. M. Xia; X. X. Xie; B. Xin; G. F. Xu; H. Xu; S. T. Xue; M. L. Yan; F. Yang; H. X. Yang; J. Yang; Y. X. Yang; M. Ye; Y. X. Ye; L. H. Yi; Z. Y. Yi; C. S. Yu; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Y. Zhang; J. Zhang; J. W. Zhang; Q. J. Zhang; S. Q. Zhang; X. M. Zhang; X. Y. Zhang; Y. Y. Zhang; Yiyun Zhang; Z. P. Zhang; Z. Q. Zhang; D. X. Zhao; J. B. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; X. J. Zhao; Y. B. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; L. S. Zheng; Z. P. Zheng; X. C. Zhong; B. Q. Zhou; G. M. Zhou; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2004-01-01

69

Partial wave analysis of chic0-->pi+piK+K-  

Microsoft Academic Search

A partial wave analysis of chic0-->pi+pi-K+K- in psi(2S)-->gammachic0 decay is presented using a sample of 14×106 psi(2S) events accumulated by the BES II detector. The data are fitted to the sum of relativistic covariant tensor amplitudes for intermediate resonant decay modes. From the fit, significant contributions to chic0 decays from the channels f0(980)f0(980), f0(980)f0(2200), f0(1370)f0(1710), K*(892)0 Kmacr *(892)0, K0*(1430) Kmacr

M. Ablikim; J. Z. Bai; Y. Ban; J. G. Bian; X. Cai; H. F. Chen; H. S. Chen; H. X. Chen; J. C. Chen; Jin Chen; Y. B. Chen; S. P. Chi; Y. P. Chu; X. Z. Cui; Y. S. Dai; Z. Y. Deng; L. Y. Dong; Q. F. Dong; S. X. Du; Z. Z. Du; J. Fang; S. S. Fang; C. D. Fu; C. S. Gao; Y. N. Gao; S. D. Gu; Y. T. Gu; Y. N. Guo; Y. Q. Guo; Z. J. Guo; F. A. Harris; K. L. He; M. He; Y. K. Heng; H. M. Hu; T. Hu; G. S. Huang; X. P. Huang; X. T. Huang; X. B. Ji; X. S. Jiang; J. B. Jiao; D. P. Jin; S. Jin; Yi Jin; Y. F. Lai; G. Li; H. B. Li; H. H. Li; J. Li; R. Y. Li; S. M. Li; W. D. Li; W. G. Li; X. L. Li; X. Q. Li; Y. L. Li; Y. F. Liang; H. B. Liao; C. X. Liu; F. Liu; Fang Liu; H. H. Liu; H. M. Liu; J. Liu; J. P. Liu; R. G. Liu; Z. A. Liu; F. Lu; G. R. Lu; H. J. Lu; J. G. Lu; C. L. Luo; F. C. Ma; H. L. Ma; L. L. Ma; Q. M. Ma; X. B. Ma; Z. P. Mao; X. H. Mo; J. Nie; S. L. Olsen; H. P. Peng; N. D. Qi; H. Qin; J. F. Qiu; Z. Y. Ren; G. Rong; L. Y. Shan; L. Shang; D. L. Shen; X. Y. Shen; H. Y. Sheng; F. Shi; X. Shi; H. S. Sun; J. F. Sun; S. S. Sun; Y. Z. Sun; Z. J. Sun; Z. Q. Tan; X. Tang; Y. R. Tian; G. L. Tong; G. S. Varner; D. Y. Wang; L. Wang; M. Wang; P. Wang; W. F. Wang; Y. F. Wang; Z. Wang; Zheng Wang; C. L. Wei; D. H. Wei; N. Wu; X. M. Xia; X. X. Xie; B. Xin; G. F. Xu; Y. Xu; M. L. Yan; F. Yang; H. X. Yang; J. Yang; Y. X. Yang; M. H. Ye; Y. X. Ye; Z. Y. Yi; G. W. Yu; C. Z. Yuan; J. M. Yuan; Y. Yuan; S. L. Zang; Y. Zeng; Yu Zeng; B. X. Zhang; C. C. Zhang; D. H. Zhang; H. Y. Zhang; J. W. Zhang; Q. J. Zhang; X. M. Zhang; X. Y. Zhang; Yiyun Zhang; Z. P. Zhang; Z. Q. Zhang; D. X. Zhao; J. W. Zhao; M. G. Zhao; P. P. Zhao; W. R. Zhao; Z. G. Zhao; H. Q. Zheng; J. P. Zheng; Z. P. Zheng; L. Zhou; N. F. Zhou; K. J. Zhu; Q. M. Zhu; Y. C. Zhu; Y. S. Zhu; Yingchun Zhu; Z. A. Zhu; B. A. Zhuang; X. A. Zhuang; B. S. Zou

2005-01-01

70

Improved Measurements of CP-Violating Asymmetry Amplitudes in B0-->pi+pi- Decays  

Microsoft Academic Search

We present updated measurements of the CP-violating parameters Spipi and Cpipi in B0-->pi+pi- decays. Using a sample of 227×106 Upsilon(4S)-->B Bmacr decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we observe 467±33 signal decays and measure Spipi=-0.30±0.17(stat)±0.03(syst) and Cpipi=-0.09±0.15(stat)±0.04(syst).

B. Aubert; R. Barate; D. Boutigny; F. Couderc; Y. Karyotakis; J. P. Lees; V. Poireau; V. Tisserand; A. Zghiche; E. Grauges-Pous; A. Palano; A. Pompili; J. C. Chen; N. D. Qi; G. Rong; P. Wang; Y. S. Zhu; G. Eigen; I. Ofte; B. Stugu; G. S. Abrams; A. W. Borgland; A. B. Breon; D. N. Brown; J. Button-Shafer; R. N. Cahn; E. Charles; C. T. Day; M. S. Gill; A. V. Gritsan; Y. Groysman; R. G. Jacobsen; R. W. Kadel; J. Kadyk; L. T. Kerth; Yu. G. Kolomensky; G. Kukartsev; G. Lynch; L. M. Mir; P. J. Oddone; T. J. Orimoto; M. Pripstein; N. A. Roe; M. T. Ronan; W. A. Wenzel; M. Barrett; K. E. Ford; T. J. Harrison; A. J. Hart; C. M. Hawkes; S. E. Morgan; A. T. Watson; M. Fritsch; K. Goetzen; T. Held; H. Koch; B. Lewandowski; M. Pelizaeus; K. Peters; T. Schroeder; M. Steinke; J. T. Boyd; J. P. Burke; N. Chevalier; W. N. Cottingham; M. P. Kelly; T. E. Latham; F. F. Wilson; T. Cuhadar-Donszelmann; C. Hearty; N. S. Knecht; T. S. Mattison; J. A. McKenna; D. Thiessen; A. Khan; P. Kyberd; L. Teodorescu; A. E. Blinov; V. E. Blinov; V. P. Druzhinin; V. B. Golubev; V. N. Ivanchenko; E. A. Kravchenko; A. P. Onuchin; S. I. Serednyakov; Yu. I. Skovpen; E. P. Solodov; A. N. Yushkov; D. Best; M. Bruinsma; M. Chao; I. Eschrich; D. Kirkby; A. J. Lankford; M. Mandelkern; R. K. Mommsen; W. Roethel; D. P. Stoker; C. Buchanan; B. L. Hartfiel; A. J. R. Weinstein; S. D. Foulkes; J. W. Gary; O. Long; B. C. Shen; K. Wang; D. Del Re; H. K. Hadavand; E. J. Hill; D. B. Macfarlane; H. P. Paar; Sh. Rahatlou; V. Sharma; J. W. Berryhill; C. Campagnari; A. Cunha; B. Dahmes; T. M. Hong; A. Lu; M. A. Mazur; J. D. Richman; W. Verkerke; T. W. Beck; A. M. Eisner; C. J. Flacco; C. A. Heusch; J. Kroseberg; W. S. Lockman; G. Nesom; T. Schalk; B. A. Schumm; A. Seiden; P. Spradlin; D. C. Williams; M. G. Wilson; J. Albert; E. Chen; G. P. Dubois-Felsmann; A. Dvoretskii; D. G. Hitlin; I. Narsky; T. Piatenko; F. C. Porter; A. Ryd; A. Samuel; S. Yang; S. Jayatilleke; G. Mancinelli; B. T. Meadows; M. D. Sokoloff; F. Blanc; P. Bloom; S. Chen; W. T. Ford; U. Nauenberg; A. Olivas; P. Rankin; W. O. Ruddick; J. G. Smith; K. A. Ulmer; J. Zhang; L. Zhang; A. Chen; E. A. Eckhart; J. L. Harton; A. Soffer; W. H. Toki; R. J. Wilson; Q. Zeng; B. Spaan; D. Altenburg; T. Brandt; J. Brose; M. Dickopp; E. Feltresi; A. Hauke; H. M. Lacker; E. Maly; R. Nogowski; S. Otto; A. Petzold; G. Schott; J. Schubert; K. R. Schubert; R. Schwierz; J. E. Sundermann; D. Bernard; G. R. Bonneaud; P. Grenier; S. Schrenk; Ch. Thiebaux; G. Vasileiadis; M. Verderi; D. J. Bard; P. J. Clark; F. Muheim; S. Playfer; Y. Xie; M. Andreotti; V. Azzolini; D. Bettoni; C. Bozzi; R. Calabrese; G. Cibinetto; E. Luppi; M. Negrini; L. Piemontese; A. Sarti; F. Anulli; R. Baldini-Ferroli; A. Calcaterra; R. de Sangro; G. Finocchiaro; P. Patteri; I. M. Peruzzi; M. Piccolo; A. Zallo; A. Buzzo; R. Capra; R. Contri; G. Crosetti; M. Lo Vetere; M. Macri; M. R. Monge; S. Passaggio; C. Patrignani; E. Robutti; A. Santroni; S. Tosi; S. Bailey; G. Brandenburg; K. S. Chaisanguanthum; M. Morii; E. Won; R. S. Dubitzky; U. Langenegger; J. Marks; U. Uwer; W. Bhimji; D. A. Bowerman; P. D. Dauncey; U. Egede; J. R. Gaillard; G. W. Morton; J. A. Nash; M. B. Nikolich; G. P. Taylor; M. J. Charles; G. J. Grenier; U. Mallik; A. K. Mohapatra; J. Cochran; H. B. Crawley; J. Lamsa; W. T. Meyer; S. Prell; E. I. Rosenberg; A. E. Rubin; J. Yi; N. Arnaud; M. Davier; X. Giroux; G. Grosdidier; A. Höcker; F. Le Diberder; V. Lepeltier; A. M. Lutz; T. C. Petersen; M. Pierini; S. Plaszczynski; M. H. Schune; G. Wormser; C. H. Cheng; D. J. Lange; M. C. Simani; D. M. Wright; A. J. Bevan; C. A. Chavez; J. P. Coleman; I. J. Forster; J. R. Fry; E. Gabathuler; R. Gamet; D. E. Hutchcroft; R. J. Parry; D. J. Payne; C. Touramanis; C. M. Cormack; F. di Lodovico; C. L. Brown; G. Cowan; R. L. Flack; H. U. Flaecher; M. G. Green; P. S. Jackson; T. R. McMahon; S. Ricciardi; F. Salvatore; M. A. Winter; C. L. Davis; J. Allison; N. R. Barlow; R. J. Barlow; M. C. Hodgkinson; G. D. Lafferty; M. T. Naisbit; J. C. Williams; C. Chen; A. Farbin; W. D. Hulsbergen; A. Jawahery; D. Kovalskyi; C. K. Lae; V. Lillard; D. A. Roberts; G. Blaylock; C. Dallapiccola; S. S. Hertzbach; R. Kofler; V. B. Koptchev; T. B. Moore; S. Saremi; H. Staengle; S. Willocq; R. Cowan; K. Koeneke; G. Sciolla; S. J. Sekula; F. Taylor; R. K. Yamamoto; P. M. Patel; S. H. Robertson; A. Lazzaro; V. Lombardo; F. Palombo; J. M. Bauer; L. Cremaldi; V. Eschenburg; R. Godang; R. Kroeger; J. Reidy; D. A. Sanders; D. J. Summers; H. W. Zhao; S. Brunet; D. Côté; P. Taras; H. Nicholson; N. Cavallo; F. Fabozzi; C. Gatto; L. Lista; D. Monorchio; P. Paolucci; D. Piccolo; C. Sciacca; M. Baak; H. Bulten; G. Raven; H. L. Snoek; L. Wilden; C. P. Jessop; J. M. Losecco; T. Allmendinger; G. Benelli; K. K. Gan; K. Honscheid; D. Hufnagel; H. Kagan; R. Kass; T. Pulliam

2005-01-01

71

Improved measurements of CP-violating asymmetry amplitudes in B0-->pi+pi- decays.  

PubMed

We present updated measurements of the CP-violating parameters Spipi and Cpipi in B0-->pi+pi- decays. Using a sample of 227x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at SLAC, we observe 467+/-33 signal decays and measure Spipi=-0.30+/-0.17(stat)+/-0.03(syst) and Cpipi=-0.09+/-0.15(stat)+/-0.04(syst). PMID:16241716

Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges-Pous, E; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; Macfarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Zhang, J; Zhang, L; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Nogowski, R; Otto, S; Petzold, A; Schott, G; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Mohapatra, A K; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Pierini, M; Plaszczynski, S; Schune, M H; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M

2005-10-01

72

Search for CP violation in the decays D0 --> K- K+ and D0 --> pi- pi+.  

PubMed

We measure time-integrated CP-violating asymmetries of neutral charmed mesons in the modes D0 --> K(-) K(+) and D0 --> pi(-) pi(+) with the highest precision to date by using D0 --> K(-) pi(+) decays to correct detector asymmetries. An analysis of 385.8 fb(-1) of data collected with the BABAR detector yields values of a(CP)(KK)=(0.00+/-0.34(stat)+/-0.13(syst))% and a(CP)(pipi)=(-0.24+/-0.52(stat)+/-0.22(syst))%, which agree with standard model predictions. PMID:18352456

Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Bailey, D; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G

2008-02-15

73

New Insights into Hydrogen Bonding and Stacking Interactions in Cellulose  

SciTech Connect

In this quantum chemical study, we explore hydrogen bonding (H-bonding) and stacking interactions in different crystalline cellulose allomorphs, namely cellulose I and cellulose IIII. We consider a model system representing a cellulose crystalline core, made from six cellobiose units arranged in three layers with two chains per layer. We calculate the contributions of intrasheet and intersheet interactions to the structure and stability in both cellulose I and cellulose IIII crystalline cores. Reference structures for this study were generated from molecular dynamics simulations of water-solvated cellulose I and IIII fibrils. A systematic analysis of various conformations describing different mutual orientations of cellobiose units is performed using the hybrid density functional theory (DFT) with the M06-2X with 6-31+G (d, p) basis sets. We dissect the nature of the forces that stabilize the cellulose I and cellulose IIII crystalline cores and quantify the relative strength of H-bonding and stacking interactions. Our calculations demonstrate that individual H-bonding interactions are stronger in cellulose I than in cellulose IIII. We also observe a significant contribution from cooperative stacking interactions to the stabilization of cellulose I . In addition, the theory of atoms-in-molecules (AIM) has been employed to characterize and quantify these intermolecular interactions. AIM analyses highlight the role of nonconventional CH O H-bonding in the cellulose assemblies. Finally, we calculate molecular electrostatic potential maps for the cellulose allomorphs that capture the differences in chemical reactivity of the systems considered in our study.

Langan, Paul [ORNL

2011-01-01

74

Study of B0 --> J\\/psiK(*)0pi+pi- Decays with the Collider Detector at Fermilab  

Microsoft Academic Search

We report a study of the decays B0-->J\\/psiK(*)0pi+pi-, which involve the creation of a uubar or ddbar quark pair in addition to a bbar-->cbar(csbar) decay. The data sample consists of 110 pb-1 of ppbar collisions at (s) = 1.8 TeV collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995. We measure the branching fractions to be B(B0-->J\\/psiK*0pi+pi-)

T. Affolder; H. Akimoto; A. Akopian; M. G. Albrow; P. Amaral; D. Amidei; K. Anikeev; J. Antos; G. Apollinari; T. Arisawa; A. Artikov; T. Asakawa; W. Ashmanskas; F. Azfar; P. Azzi-Bacchetta; N. Bacchetta; H. Bachacou; S. Bailey; P. de Barbaro; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; S. Baroiant; M. Barone; G. Bauer; F. Bedeschi; S. Belforte; W. H. Bell; G. Bellettini; J. Bellinger; D. Benjamin; J. Bensinger; A. Beretvas; J. P. Berge; J. Berryhill; A. Bhatti; M. Binkley; D. Bisello; M. Bishai; R. E. Blair; C. Blocker; K. Bloom; B. Blumenfeld; S. R. Blusk; A. Bocci; A. Bodek; W. Bokhari; G. Bolla; Y. Bonushkin; D. Bortoletto; J. Boudreau; A. Brandl; S. van den Brink; C. Bromberg; M. Brozovic; E. Brubaker; N. Bruner; E. Buckley-Geer; J. Budagov; H. S. Budd; K. Burkett; G. Busetto; A. Byon-Wagner; K. L. Byrum; S. Cabrera; P. Calafiura; M. Campbell; W. Carithers; J. Carlson; D. Carlsmith; W. Caskey; A. Castro; D. Cauz; A. Cerri; A. W. Chan; P. S. Chang; P. T. Chang; J. Chapman; C. Chen; Y. C. Chen; M.-T. Cheng; M. Chertok; G. Chiarelli; I. Chirikov-Zorin; G. Chlachidze; F. Chlebana; L. Christofek; M. L. Chu; Y. S. Chung; C. I. Ciobanu; A. G. Clark; A. P. Colijn; A. Connolly; J. Conway; M. Cordelli; J. Cranshaw; R. Cropp; R. Culbertson; D. Dagenhart; S. D'Auria; F. Dejongh; S. dell'Agnello; M. dell'Orso; L. Demortier; M. Deninno; P. F. Derwent; T. Devlin; J. R. Dittmann; A. Dominguez; S. Donati; J. Done; M. D'Onofrio; T. Dorigo; N. Eddy; K. Einsweiler; J. E. Elias; E. Engels; R. Erbacher; D. Errede; S. Errede; Q. Fan; H.-C. Fang; R. G. Feild; J. P. Fernandez; C. Ferretti; R. D. Field; I. Fiori; B. Flaugher; G. W. Foster; M. Franklin; J. Freeman; J. Friedman; Y. Fukui; I. Furic; S. Galeotti; A. Gallas; M. Gallinaro; T. Gao; M. Garcia-Sciveres; A. F. Garfinkel; P. Gatti; C. Gay; D. W. Gerdes; P. Giannetti; P. Giromini; V. Glagolev; D. Glenzinski; M. Gold; J. Goldstein; I. Gorelov; A. T. Goshaw; Y. Gotra; K. Goulianos; C. Green; G. Grim; P. Gris; L. Groer; C. Grosso-Pilcher; M. Guenther; G. Guillian; J. Guimaraes da Costa; R. M. Haas; C. Haber; S. R. Hahn; C. Hall; T. Handa; R. Handler; W. Hao; F. Happacher; K. Hara; A. D. Hardman; R. M. Harris; F. Hartmann; K. Hatakeyama; J. Hauser; J. Heinrich; A. Heiss; M. Herndon; C. Hill; K. D. Hoffman; C. Holck; R. Hollebeek; L. Holloway; B. T. Huffman; R. Hughes; J. Huston; J. Huth; H. Ikeda; J. Incandela; G. Introzzi; J. Iwai; Y. Iwata; E. James; M. Jones; U. Joshi; H. Kambara; T. Kamon; T. Kaneko; K. Karr; H. Kasha; Y. Kato; T. A. Keaffaber; K. Kelley; M. Kelly; R. D. Kennedy; R. Kephart; D. Khazins; T. Kikuchi; B. Kilminster; B. J. Kim; D. H. Kim; H. S. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; M. Kirby; M. Kirk; L. Kirsch; S. Klimenko; P. Koehn; K. Kondo; J. Konigsberg; A. Korn; A. Korytov; E. Kovacs; J. Kroll; M. Kruse; S. E. Kuhlmann; K. Kurino; T. Kuwabara; A. T. Laasanen; N. Lai; S. Lami; S. Lammel; J. Lancaster; M. Lancaster; R. Lander; A. Lath; G. Latino; T. Lecompte; A. M. Lee; K. Lee; S. Leone; J. D. Lewis; M. Lindgren; T. M. Liss; J. B. Liu; Y. C. Liu; D. O. Litvintsev; O. Lobban; N. Lockyer; J. Loken; M. Loreti; D. Lucchesi; P. Lukens; S. Lusin; L. Lyons; J. Lys; R. Madrak; K. Maeshima; P. Maksimovic; L. Malferrari; M. Mangano; M. Mariotti; G. Martignon; A. Martin; J. A. Matthews; J. Mayer; P. Mazzanti; K. S. McFarland; P. McIntyre; E. McKigney; M. Menguzzato; A. Menzione; P. Merkel; C. Mesropian; A. Meyer; T. Miao; R. Miller; J. S. Miller; H. Minato; S. Miscetti; M. Mishina; G. Mitselmakher; N. Moggi; E. Moore; R. Moore; Y. Morita; T. Moulik; M. Mulhearn; A. Mukherjee; T. Muller; A. Munar; P. Murat; S. Murgia; J. Nachtman; V. Nagaslaev; S. Nahn; H. Nakada; I. Nakano; C. Nelson; T. Nelson; C. Neu; D. Neuberger; C. Newman-Holmes; C.-Y. P. Ngan; H. Niu; L. Nodulman; A. Nomerotski; S. H. Oh; Y. D. Oh; T. Ohmoto; T. Ohsugi; R. Oishi; T. Okusawa; J. Olsen; W. Orejudos; C. Pagliarone; F. Palmonari; R. Paoletti; V. Papadimitriou; D. Partos; J. Patrick; G. Pauletta; M. Paulini; C. Paus; D. Pellett; L. Pescara; T. J. Phillips; G. Piacentino; K. T. Pitts; A. Pompos; L. Pondrom; G. Pope; M. Popovic; F. Prokoshin; J. Proudfoot; F. Ptohos; O. Pukhov; G. Punzi; A. Rakitine; F. Ratnikov; D. Reher; A. Reichold; A. Ribon; W. Riegler; F. Rimondi; L. Ristori; M. Riveline; W. J. Robertson; A. Robinson; T. Rodrigo; S. Rolli; L. Rosenson; R. Roser; R. Rossin; C. Rott; A. Roy; A. Ruiz; A. Safonov; R. St. Denis; W. K. Sakumoto; D. Saltzberg; C. Sanchez; A. Sansoni; L. Santi; H. Sato; P. Savard; P. Schlabach; E. E. Schmidt; M. P. Schmidt; M. Schmitt; L. Scodellaro; A. Scott; A. Scribano; S. Segler; S. Seidel; Y. Seiya; A. Semenov; F. Semeria; T. Shah; M. D. Shapiro; P. F. Shepard; T. Shibayama; M. Shimojima; M. Shochet; A. Sidoti; J. Siegrist; A. Sill; P. Sinervo; P. Singh; A. J. Slaughter; K. Sliwa; C. Smith; F. D. Snider; A. Solodsky; J. Spalding; T. Speer

2002-01-01

75

Stacking and hydrogen bond interactions between adenine and gallic acid.  

PubMed

We have performed DFT and DFT-SAPT calculations on dimers of gallic acid, the model system for plant polyphenols, and the DNA base adenine. These dimers were selected for this study as they exhibit simultaneously hydrogen bonds and stacking interactions and it allows to quantify the relative values of these interactions. We calculate the relationships between the stability of the complexes, the charge transfer between monomers and the properties of the intermolecular bonds including hydrogen bonds and other bonds that do not involve hydrogen atoms. DFT-SAPT calculations were also performed to obtain the participation of the different types of energy and so the resulting physical effects. The results show that the presence of hydrogen bonds is the main stabilizing factor for dimers: the higher number and strength, the lower the dimer energy. The contribution of stacking to the stabilization is related to the strength and number of bonds between non-hydrogen atoms and quantified by the contribution of the dispersion terms to the interaction energy. Dimers I and II are mainly stabilized due to hydrogen bonds whereas dimer III is mainly stabilized by stacking interactions. PMID:24154612

Lorenzo, Isidro; Graña, Ana M

2013-12-01

76

Precision measurement of {pi}{pi} scattering lengths at the NA48/2 experiment  

SciTech Connect

The NA48/2 experiment at CERN [1] collected {approx}18{center_dot}10{sup 9} charged kaon decays during the years 2003/4. Along with the primary goals of the collaboration, i.e. the measurement of the CP-violating asymmetry in the K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup +}{pi}{sup -} and K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup 0}{pi}{sup 0} decays thanks to the simultaneous collection of K{sup +} and K{sup -} events, the collected data allowed to perform many other interesting analyses. In this paper two independent measurements of {pi}{pi} scattering lengths will be reviewed, using NA48/2 data from the K{sup {+-}}{yields}e{sup {+-}}{nu}{pi}{sup +}{pi}{sup -} decay and from the cusp effect in K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup +}{pi}{sup -} respectively.

Venditti, Stefano [Universita di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy)

2010-12-28

77

Dalitz Plot Analysis of B{sup -{yields}}D{sup +{pi}-{pi}-}  

SciTech Connect

We present a Dalitz plot analysis of B{sup -{yields}}D{sup +{pi}-{pi}-} decays, based on a sample of about 383 million {Upsilon}(4S){yields}BB-bar decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The analysis has been published previously in [1]. We measure the inclusive branching fraction of the three-body decay to be B(B{sup -{yields}}D{sup +{pi}+{pi}-}) = (1.08{+-}0.03(stat){+-}0.05(syst))x10{sup -3}. We observe the established D{sub 2}*{sup 0} and confirm the existence of D{sub 0}*{sup 0} in their decays to D{sup +{pi}-}, where the D{sub 2}*{sup 0} and D{sub 0}*{sup 0} are the 2{sup +} and 0{sup +} cu-bar P-wave states, respectively. We measure the masses and widths of D{sub 2}*{sup 0} and {Gamma}D{sub 0}*{sup 0} to be: mD{sub 2}* = (2460.4{+-}1.2{+-}1.2{+-}1.9) MeV/c{sup 2}, {Gamma}D{sub 2}* = (41.8{+-}2.5{+-}2.1{+-}2.0) MeV, mD{sub 0}* = (2297{+-}8{+-}5{+-}19) MeV/c{sup 2}, {Gamma}D{sub 0}* = (273{+-}12{+-}17{+-}45) MeV. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.

Karbach, T. M. [Technische Universitaet Dortmund (Germany)

2010-08-05

78

Measurement of Branching Fractions and Mass Spectra of B to K pi pi gamma  

SciTech Connect

The authors present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B {yields} K{pi}{pi}{gamma} in the range m{sub K{pi}{pi}} < 1.8 GeV/c{sup 2}. They reconstruct four final states: K{sup +}{pi}{sup -}{pi}{sup +}{gamma}, K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}, K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}{gamma}, and K{sub S}{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}, where K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. Using 232 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II asymmetric-energy storage ring, they measure the branching fractions {Beta}(B{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{gamma}) = (2.95 {+-} 0.13(stat.) {+-} 0.20(syst)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}) = (4.07 {+-} 0.22(stat.) {+-} 0.31(syst.)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup +}{pi}{sup -}{gamma}) = (1.85 {+-} 0.21(stat.) {+-} 0.12(syst.)) x 10{sup -5}, and {Beta}(B{sup +} {yields} K{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}) = (4.56 {+-} 0.42(stat.) {+-} 0.31(syst.)) x 10{sup -5}.

Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

2005-07-12

79

Intriguing relations of interaction energy components in stacked nucleic acids  

NASA Astrophysics Data System (ADS)

Major components of the interaction energy that define several approximate levels starting from second order Möller-Plesset theory were studied for 58 stacked nucleic acid dimers. They included typical B-DNA and A-DNA structures, and selected published geometries. A survey of the various terms yields an unexpected correlation between the Pauli exchange and dispersion or correlation terms, which holds for each class of similar planar geometries and for various basis sets. The geometries that exhibit these correlations span a specific range of molecular overlaps when compared to a model benzene-pyridine stacked dimer. Also, the relationship between electrostatic interactions and MP2 stabilization energies reported earlier is confirmed and a prediction interval of practical relevance is estimated.

Langner, Karol M.; Sokalski, W. Andrzej; Leszczynski, J.

2007-09-01

80

Atomic-scale details of dislocation - stacking fault tetrahedra interaction.  

SciTech Connect

Stacking fault tetrahedra (SFTs) are formed during irradiation of fcc. metals and alloys with low stacking fault energy. The high number density of SFTs observed suggests that they should contribute to radiation-induced hardening and, therefore, be taken into account when estimating mechanical property changes of irradiated materials. The key issue is to describe the interaction between a moving dislocation and an individual SFT, which is characterized by a small physical scale of about 100 nm. In this paper we present results of an atomistic simulation of edge and screw dislocations interacting with small SFTs at different temperatures and strain rates and present mechanisms which can explain the formation of defect-free channels observed experimentally.

Osetskiy, Yury N [ORNL; Stoller, Roger E [ORNL; Rodney, David [Genie Physique et Mecanique des Materiaux; Bacon, David J [University of Liverpool

2005-01-01

81

Observation of CP Violation in B0 to K+pi- and B0 to pi+pi-  

SciTech Connect

The authors report observations of CP violation in the decays B{sup 0} {yields} K{sup +}{pi}{sup -} and B{sup 0} {yields} {pi}{sup +}{pi}{sup -} in a sample of 383 million {Upsilon}(4S) {yields} B{bar B} events. They find 4372 {+-} 82 B{sup 0} {yields} K{sup +}{pi}{sup -} decays and measure the direct Cp-violating charge asymmetry {Alpha}{sub K{pi}} = -0.107 {+-} 0.018(stat){sub -0.004}{sup +0.007}(syst), which excludes the CP-conserving hypothesis with a significance of 5.5 standard deviations. In the same sample they find 1139 {+-} 49 B{sup 0} {yields} {pi}{sup +}{pi}{sup -} decays and measure the CP-violating asymmetries S{sub {pi}{pi}} = -0.60 {+-} 0.11(stat) {+-} 0.03(syst) and C{sub {pi}{pi}} = -0.21 {+-} 0.09(stat) {+-} 0.02(syst). CP conservation in B{sup 0} {yields} {pi}{sup +}{pi}{sup -} (S{sub {pi}{pi}} = C{sub {pi}{pi}} = 0) is excluded at a confidence level 1-C.L. = 8 x 10{sup -8}, corresponding to 5.4 standard deviations.

Aubert, B.

2007-03-14

82

Force-field dependence of Boltzmann weighting factors on predicted pi-pi* circular dichroic spectra of cyclo (Gly-Pro-Gly)2.  

PubMed

Semi-empirical energy calculations were performed for published conformations of cyclo (Gly-Pro-Gly)2 using different force fields (DISCOVER cvff and cff91, AMBER, and CHARMM). The resulting potential energies were then used to create Boltzmann weighting factors for an ensemble of cyclo(Gly-Pro-Gly)2 structures. The dipole interaction model was used to predict pi-pi* circular dichroic spectra (CD) for the individual structures of cyclo(Gly-Pro-Gly)2. The Boltzmann weighting factors were applied to the individual spectra so that a composite spectrum was constructed to represent a CD arising from a collection of different structures in solution. Weighting factors determined from different force fields were compared. Boltzmann-weighted spectra better resembled the experimental CD than any calculated spectrum using only a single conformation of cyclo (Gly-Pro-Gly)2. The structures most heavily weighted contained at least one type I beta-turn. PMID:8836772

MacFarlane, K J; Humbert, M M; Thomasson, K A

1996-06-01

83

Thermal corrections to {pi}-{pi} scattering lengths in the linear sigma model  

SciTech Connect

In this article we address the problem of getting the temperature dependence of the {pi}-{pi} scattering lengths in the frame of the linear sigma model. Using the real time formalism, we calculate all the relevant one loop diagrams. The temperature corrections are only considered in the pion sector, due to the Boltzmann suppression for heavier fields like the sigma meson. From this analysis we obtain the thermal behavior of the s waves scattering lengths a{sub 0}{sup 0} and a{sub 0}{sup 2} associated to isospin I=0 and I=2, respectively. If we normalize with the zero temperature value it turns out that (a{sub 0}{sup 0}(T)/a{sub 0}{sup 0}) grows with temperature, whereas the opposite occurs with (a{sub 0}{sup 2}(T)/a{sub 0}{sup 2}). Finally we compare our results with other determinations of the scattering lengths based on the Nambu-Jona-Lasinio model and chiral perturbation theory.

Loewe, M.; Martinez-Villalobos, C. [Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile)

2008-05-15

84

Precision measurement of the X(3872) mass in J/psi pi(+) pi(-) decays.  

PubMed

We present an analysis of the mass of the X(3872) reconstructed via its decay to J/psi pi(+)pi(-) using 2.4 fb(-1) of integrated luminosity from pp collisions at square root(s)=1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The possible existence of two nearby mass states is investigated. Within the limits of our experimental resolution the data are consistent with a single state, and having no evidence for two states we set upper limits on the mass difference between two hypothetical states for different assumed ratios of contributions to the observed peak. For equal contributions, the 95% confidence level upper limit on the mass difference is 3.6 MeV/c(2). Under the single-state model the X(3872) mass is measured to be 3871.61+/-0.16(stat)+/-0.19(syst) MeV/c(2), which is the most precise determination to date. PMID:19905622

Aaltonen, T; Adelman, J; Akimoto, T; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Beringer, J; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burke, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Calancha, C; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Chwalek, T; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cordelli, M; Cortiana, G; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lorenzo, G; Dell'Orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Derwent, P F; Di Canto, A; di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Elagin, A; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Garosi, P; Genser, K; Gerberich, H; Gerdes, D; Gessler, A; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Han, B-Y; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hays, C; Heck, M; Heijboer, A; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Ketchum, W; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhr, T; Kulkarni, N P; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, E; Lee, H S; Lee, S W; Leone, S; Lewis, J D; Lin, C-S; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lucchesi, D; Luci, C; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Merkel, P; Mesropian, C; Miao, T; Miladinovic, N; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moggi, N; Mondragon, M N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Nett, J; Neu, C; Neubauer, M S; Neubauer, S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Osterberg, K; Pagan Griso, S; Pagliarone, C

2009-10-01

85

Delta I=3/2 K to pi-pi decays with nearly physical kinematics  

NASA Astrophysics Data System (ADS)

The \\Delta I = 3/2 K to pi pi decay amplitude is calculated on RBC/UKQCD 32^3 times 64, L_s=32 dynamical lattices with 2+1 flavours of domain wall fermions using the Dislocation Suppressing Determinant Ratio and Iwasaki gauge action. The calculation is performed close to the physical pion mass (m_pi = 142.9(1.1) MeV and with a single lattice spacing (a^-1= 1.375(9) GeV.) We find Re(A_2) = (1.436 \\pm 0.063_{stat} \\pm 0.258_{syst}) times 10^-8 GeV and Im(A_2) = (-6.29 \\pm 0.46_{stat} \\pm 1.20_{syst})\\times 10^{-13} GeV. These results are combined with the experimental result for epsilon'/epsilon to predict Im(A_0) = -5.32(64)_{stat}(71)_{syst}\\times 10^{-11} GeV within the Standard Model. We also perform a reweighting analysis to investigate the effects of partial quenching in the light-quark sector of our calculation. Following reweighting we find Re(A_2) = (1.52\\pm 0.14_{stat}) \\times 10^-8 GeV and Im(A_2) = (-6.47 \\pm 0.55_{stat})\\times 10^-13 GeV, which are consistent with our main results.

Goode, E.; Lightman, M.

86

Diffractive Dissociation into {pi}{sup -{pi}-{pi}+} Final States at COMPASS  

SciTech Connect

QCD predicts gluonic excitations like hybrids to contribute to the meson spectrum in addition to qq-bar pair configurations. The most promising way to identify such states is the search for J{sup PC} quantum number combinations which are forbidden in the constituent quark model. The fixed target COMPASS experiment at CERN offers the opportunity to search for such states in the light quark sector with an unprecedented statistics.Diffractive reactions of 190 GeV/c pions on a lead target were studied by COMPASS during a pilot run in 2004. A Partial Wave Analysis (PWA) of the {pi}{sup -{pi}-{pi}+} final state with 42 waves including acceptance corrections through a phase-space Monte Carlo simulation of the spectrometer was performed. The exotic {pi}{sup 1}(1600) meson with quantum numbers J{sup PC} = 1{sup -+} has been clearly established in the rho-pi decay channel with a mass of 1660{+-}10(stat) MeV/c{sup 2} and a width of 269{+-}21(stat) MeV/c{sup 2}. The improved detector performance in 2008 allows us to study this channel with significantly higher statistics. First results of the ongoing analysis of the 2008 data taking period, using a 190 GeV/c pion beam on a liquid hydrogen target are presented in this paper.

Haas, Florian [Physik Department E18, Technische Universitaet Muenchen James Franck Str., D-85748 Garching (Germany)

2011-10-24

87

Diffractive Dissociation into {pi}{sup -{pi}-{pi}+} Final States at COMPASS  

SciTech Connect

QCD predicts gluonic excitations like hybrids to contribute to the meson spectrum in addition to qq-bar pair configurations. The most promising way to identify such states is the search for J{sup PC} quantum number combinations which are forbidden in the constituent quark model. The fixed target COMPASS experiment at CERN offers the opportunity to search for such states in the light quark sector with an unprecedented statistics.Diffractive reactions of 190 GeV/c pions on a lead target were studied by COMPASS during a pilot run in 2004. A Partial Wave Analysis (PWA) of the {pi}{sup -{pi}-{pi}+} final state with 42 waves including acceptance corrections through a phase-space Monte Carlo simulation of the spectrometer was performed. The exotic {pi}{sub 1}(1600) meson with quantum numbers J{sup PC} = 1{sup -+} has been clearly established in the rho-pi decay channel with a mass of 1660{+-}10(stat) MeV/c{sup 2} and a width of 269{+-}21(stat) MeV/c{sup 2}. The improved detector performance in 2008 allows us to study this channel with significantly higher statistics. First results of the ongoing analysis of the 2008 data taking period, using a 190 GeV/c pion beam on a liquid hydrogen target are presented in this paper.

Haas, Florian [Physik Department E18, Technische Universitaet Muenchen James Franck Str., D-85748 Garching (Germany)

2010-08-05

88

Study of B0 --> J/psiK(*)0pi(+)pi(-) decays with the collider detector at Fermilab.  

PubMed

We report a study of the decays B0 --> J/psiK(*)0pi(+)pi(-), which involve the creation of a uu or dd quark pair in addition to a b -->c(cs) decay. The data sample consists of 110 pb(-1) of pp collisions at square root[s] = 1.8 TeV collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995. We measure the branching fractions to be B(B0 --> J/psiK(*0)pi(+)pi(-)) = (6.6 +/- 1.9 +/- 1.1)x10(-4) and B(B0 --> J/psiK0pi(+)pi(-)) = (10.3 +/- 3.3 +/- 1.5)x10(-4). Evidence is seen for contributions from psi(2S)K(*)0, J/psiK0rho(0), J/psiK(*+)pi(-), and J/psiK1(1270). PMID:11863882

Affolder, T; Akimoto, H; Akopian, A; Albrow, M G; Amaral, P; Amidei, D; Anikeev, K; Antos, J; Apollinari, G; Arisawa, T; Artikov, A; Asakawa, T; Ashmanskas, W; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Bailey, S; de Barbaro, P; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Belforte, S; Bell, W H; Bellettini, G; Bellinger, J; Benjamin, D; Bensinger, J; Beretvas, A; Berge, J P; Berryhill, J; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Blusk, S R; Bocci, A; Bodek, A; Bokhari, W; Bolla, G; Bonushkin, Y; Bortoletto, D; Boudreau, J; Brandl, A; van den Brink, S; Bromberg, C; Brozovic, M; Brubaker, E; Bruner, N; Buckley-Geer, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Byon-Wagner, A; Byrum, K L; Cabrera, S; Calafiura, P; Campbell, M; Carithers, W; Carlson, J; Carlsmith, D; Caskey, W; Castro, A; Cauz, D; Cerri, A; Chan, A W; Chang, P S; Chang, P T; Chapman, J; Chen, C; Chen, Y C; Cheng, M-T; Chertok, M; Chiarelli, G; Chirikov-Zorin, I; Chlachidze, G; Chlebana, F; Christofek, L; Chu, M L; Chung, Y S; Ciobanu, C I; Clark, A G; Colijn, A P; Connolly, A; Conway, J; Cordelli, M; Cranshaw, J; Cropp, R; Culbertson, R; Dagenhart, D; D'Auria, S; DeJongh, F; Dell'Agnello, S; Dell'Orso, M; Demortier, L; Deninno, M; Derwent, P F; Devlin, T; Dittmann, J R; Dominguez, A; Donati, S; Done, J; D'Onofrio, M; Dorigo, T; Eddy, N; Einsweiler, K; Elias, J E; Engels, E; Erbacher, R; Errede, D; Errede, S; Fan, Q; Fang, H-C; Feild, R G; Fernandez, J P; Ferretti, C; Field, R D; Fiori, I; Flaugher, B; Foster, G W; Franklin, M; Freeman, J; Friedman, J; Fukui, Y; Furic, I; Galeotti, S; Gallas, A; Gallinaro, M; Gao, T; Garcia-Sciveres, M; Garfinkel, A F; Gatti, P; Gay, C; Gerdes, D W; Giannetti, P; Giromini, P; Glagolev, V; Glenzinski, D; Gold, M; Goldstein, J; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Green, C; Grim, G; Gris, P; Groer, L; Grosso-Pilcher, C; Guenther, M; Guillian, G; Guimaraes da Costa, J; Haas, R M; Haber, C; Hahn, S R; Hall, C; Handa, T; Handler, R; Hao, W; Happacher, F; Hara, K; Hardman, A D; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Heinrich, J; Heiss, A; Herndon, M; Hill, C; Hoffman, K D; Holck, C; Hollebeek, R; Holloway, L; Huffman, B T; Hughes, R; Huston, J; Huth, J; Ikeda, H; Incandela, J; Introzzi, G; Iwai, J; Iwata, Y; James, E; Jones, M; Joshi, U; Kambara, H; Kamon, T; Kaneko, T; Karr, K; Kasha, H; Kato, Y; Keaffaber, T A; Kelley, K; Kelly, M; Kennedy, R D; Kephart, R; Khazins, D; Kikuchi, T; Kilminster, B; Kim, B J; Kim, D H; Kim, H S; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kirby, M; Kirk, M; Kirsch, L; Klimenko, S; Koehn, P; Kondo, K; Konigsberg, J; Korn, A; Korytov, A; Kovacs, E; Kroll, J; Kruse, M; Kuhlmann, S E; Kurino, K; Kuwabara, T; Laasanen, A T; Lai, N; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lath, A; Latino, G; LeCompte, T; Lee, A M; Lee, K; Leone, S; Lewis, J D; Lindgren, M; Liss, T M; Liu, J B; Liu, Y C; Litvintsev, D O; Lobban, O; Lockyer, N; Loken, J; Loreti, M; Lucchesi, D; Lukens, P; Lusin, S; Lyons, L; Lys, J; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Mangano, M; Mariotti, M; Martignon, G; Martin, A; Matthews, J A J; Mayer, J; Mazzanti, P; McFarland, K S; McIntyre, P; McKigney, E; Menguzzato, M; Menzione, A; Merkel, P; Mesropian, C; Meyer, A; Miao, T; Miller, R; Miller, J S; Minato, H; Miscetti, S; Mishina, M; Mitselmakher, G; Moggi, N; Moore, E; Moore, R; Morita, Y; Moulik, T; Mulhearn, M; Mukherjee, A; Muller, T; Munar, A; Murat, P; Murgia, S; Nachtman, J; Nagaslaev, V; Nahn, S; Nakada, H; Nakano, I; Nelson, C; Nelson, T; Neu, C; Neuberger, D; Newman-Holmes, C; Ngan, C-Y P; Niu, H; Nodulman, L; Nomerotski, A; Oh, S H; Oh, Y D; Ohmoto, T; Ohsugi, T; Oishi, R; Okusawa, T; Olsen, J; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Partos, D; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D; Pescara, L; Phillips, T J; Piacentino, G; Pitts, K T; Pompos, A; Pondrom, L; Pope, G; Popovic, M; Prokoshin, F; Proudfoot, J; Ptohos, F; Pukhov, O; Punzi, G; Rakitine, A; Ratnikov, F; Reher, D; Reichold, A; Ribon, A; Riegler, W; Rimondi, F; Ristori, L; Riveline, M; Robertson, W J; Robinson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Roy, A; Ruiz, A; Safonov, A; St Denis, R; Sakumoto, W K; Saltzberg, D; Sanchez, C; Sansoni, A; Santi, L; Sato, H; Savard, P; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scott, A; Scribano, A; Segler, S; Seidel, S; Seiya, Y; Semenov, A; Semeria, F; Shah, T; Shapiro, M D; Shepard, P F; Shibayama, T; Shimojima, M; Shochet, M; Sidoti, A; Siegrist, J; Sill, A; Sinervo, P; Singh, P; Slaughter, A J; Sliwa, K; Smith, C; Snider, F D; Solodsky, A; Spalding, J; Speer, T; Sphicas, P; Spinella, F; Spiropulu, M; Spiegel, L; Steele, J; Stefanini, A; Strologas, J

2002-02-18

89

Observation of the Xi+c charmed baryon decays to Sigma+Kappa-pi+, Sigma+Kappa*0, and LambdaKappa-pi+pi+  

Microsoft Academic Search

We have observed two new decay modes of the charmed baryon Xi+c into Sigma+K-pi+ and Sigma+K*0 using data collected with the CLEO II detector. We also present the first measurement of the branching fraction for the previously observed decay mode Xi+c -> LambdaK-pi+pi+. The branching fractions for these three modes relative to Xi+c -> Xi-pi+pi+ are measured to be 1.18

T. Bergfeld; B. I. Eisenstein; J. Ernst; G. E. Gladding; G. D. Gollin; M. Palmer; M. Selen; J. J. Thaler; K. W. Edwards; K. W. McLean; M. Ogg; A. Bellerive; D. I. Britton; E. R. F. Hyatt; R. Janicek; D. B. Macfarlane; P. M. Patel; B. Spaan; A. J. Sadoff; R. Ammar; P. Baringer; A. Bean; D. Besson; D. Coppage; N. Copty; R. Davis; N. Hancock; S. Kotov; I. Kravchenko; N. Kwak; Y. Kubota; M. Lattery; M. Momayezi; J. K. Nelson; S. Patton; R. Poling; V. Savinov; S. Schrenk; Wang R; M. S. Alam; I. J. Kim; Z. Ling; A. H. Mahmood; J. J. O'Neill; H. Severini; C. R. Sun; F. Wappler; G. Crawford; J. E. Duboscq; R. Fulton; D. Fujino; K. K. Gan; K. Honscheid; H. Kagan; R. Kass; J. Lee; M. Sung; C. White; A. Wolf; M. M. Zoeller; X. Fu; B. Nemati; W. R. Ross; P. Skubic; M. Wood; M. Bishai; J. Fast; E. Gerndt; J. W. Hinson; T. Miao; D. H. Miller; M. Modesitt; E. I. Shibata; I. P. J. Shipsey; P. N. Wang; L. Gibbons; S. D. Johnson; Y. Kwon; S. Roberts; E. H. Thorndike; T. E. Coan; J. Dominick; V. Fadeyev; I. Korolkov; M. Lambrecht; S. Sanghera; V. Shelkov; T. Skwarnicki; R. Stroynowski; I. Volobouev; Wei G; M. Artuso; M. Gao; M. Goldberg; He D; N. Horwitz; S. Kopp; G. C. Moneti; F. Muheim; Y. Mukhin; S. Playfer; S. Stone; X. Xing; J. Bartelt; S. E. Csorna; V. Jain; S. Marka; D. Gibaut; K. Kinoshita; P. Pomianowski; B. Barish; M. Chadha; Chan S; D. F. Cowen; G. Eigen; J. S. Miller; C. O'Grady; J. Urheim; A. J. Weinstein; F. Würthwein; D. M. Asner; M. Athanas; D. W. Bliss; W. S. Brower; G. Masek; H. P. Paar; J. Gronberg; C. M. Korte; R. Kutschke; S. Menary; R. J. Morrison; S. Nakanishi; H. N. Nelson; T. K. Nelson; C. Qiao; J. D. Richman; D. Roberts; A. Ryd; H. Tajima; M. S. Witherell; R. Balest; Cho K; W. T. Ford; M. Lohner; P. Rankin; J. G. Smith; J. P. Alexander; C. Bebek; B. E. Berger; K. Berkelman; K. Bloom; T. E. Browder; D. G. Cassel; H. A. Cho; D. M. Coffman; D. S. Crowcroft; M. Dickson; P. S. Drell; D. J. Dumas; R. Ehrlich; R. Elia; P. Gaidarev; M. Garcia-Sciveres; B. Gittelman; S. W. Gray; D. L. Hartill; B. K. Heltsley; S. Henderson; C. D. Jones; S. L. Jones; J. Kandaswamy; N. Katayama; P. C. Kim; D. L. Kreinick; T. Lee; Y. Liu; G. S. Ludwig; J. Masui; J. Mevissen; N. B. Mistry; C. R. Ng; E. Nordberg; J. R. Patterson; D. Peterson; D. Riley; A. Soffer; P. Avery; A. Freyberger; K. Lingel; C. Prescott; J. Rodriguez; S. Yang; J. Yelton; G. Brandenburg; D. Cinabro; T. Liu; M. Saulnier; R. Wilson; H. Yamamoto

1996-01-01

90

Effects of steric and electronic interactions on. pi. pi. overlap in lanthanide porphyrin sandwich complexes  

SciTech Connect

Electrochemical, infrared, resonance Raman, and optical absorption data are reported for the lanthanide porphyrin sandwich complexes, Ce{sup IV}(TPP){sub 2}, Ce{sup IV}(TPP){sub 2}{sup +}, Eu{sup III}(TPP){sub 2}, Ce{sup IV}(TPnP){sub 2}, Ce{sup IV}(TPnP){sub 2}{sup +}, and Eu{sup III}(TPnP){sub 2} (TPP = meso-tetraphenylporphyrin; TPnP = meso-tetrapentylporphyrin). The two Eu{sup III} complexes contain a single hole in the porphyrin {pi} system and are electronically similar to the Ce{sup IV} sandwich porphyrin cation radicals. Variable-temperature UV-vis and near-infrared (near-IR) spectra are obtained for all four single-hole sandwiches. At high resolution and/or at low temperatures, well-resolved fine structure is observed on the intradimer charge-transfer bands (ca. 1,300 and 1,100 nm for the TPP and TPnP complexes, respectively). These absorptions are dominated by a single Franck-Condon-active vibration. This vibration is assigned as a mode, Q{sub AB}, which contains a significant amount of multicenter character and modulates inter-ring separation.

Perng, Jinghuei; Duchowski, J.K.; Bocian, D.F. (Carnegie Mellon Univ., Pittsburgh, PA (USA))

1990-08-23

91

Spectroscopic characterization of lanthanide octaethylporphyrin sandwich complexes. Effects of strong. pi. pi. interaction  

SciTech Connect

Optical absorption and resonance Raman spectra are reported for the lanthanide sandwich porphyrins, Eu{sup III}(OEP){sub 2}, Nd{sup III}(OEP){sub 2}, and La{sup III}(OEP){sub 2} (OEP = octaethylporphyrin). These complexes contain a single hole in the porphyrin {pi} system and are electronically similar to the Ce{sup IV} sandwich porphyrin cation radical Ce{sup IV}(OEP){sub 2}{sup +}. Variable-temperature (10-300 K) UV-vis and near-infrared (NIR) spectra are obtained for all four single-hole sandwiches. At high resolution and/or at low temperatures, well-resolved fine structure is observed on the intradimer charge-transfer bands (ca. 1,250 nm) of all the complexes. The absorption is dominated by a single Franck-Condon active vibration. This vibration is assigned as a mode, Q{sub AB}, which contains a significant amount of multicenter character and modulates interring separation. Vibronic analysis of the NIR band contours reveals that two system origins, separated by 400-700 cm{sup {minus}1} (depending on the complex), are present. The progressions built off the lower and higher energy origins exhibit spacings of {approximately} 250 and {approximately} 315 cm{sup {minus}1}, respectively.

Duchowski, J.K.; Bocian, D.F. (Carnegie Mellon Univ., Pittsburgh, PA (USA))

1990-04-25

92

Spectroscopic characterization of lanthanide octaethylporphyrin sandwich complexes. Effects of strong. pi. pi. interaction  

Microsoft Academic Search

Optical absorption and resonance Raman spectra are reported for the lanthanide sandwich porphyrins, Eu{sup III}(OEP)â, Nd{sup III}(OEP)â, and La{sup III}(OEP)â (OEP = octaethylporphyrin). These complexes contain a single hole in the porphyrin Ï system and are electronically similar to the Ce{sup IV} sandwich porphyrin cation radical Ce{sup IV}(OEP)â{sup +}. Variable-temperature (10-300 K) UV-vis and near-infrared (NIR) spectra are obtained for

John K. Duchowski; David F. Bocian

1990-01-01

93

Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays  

SciTech Connect

The authors present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} K{sup +}{pi}{sup -}, B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and B{sup 0} {yields} K{sup 0}{pi}{sup 0}. This update includes all data taken at the {Upsilon}(4S) resonance by the BABAR experiment at the asymmetric PEP-II B-meson factory at SLAC, corresponding to 467 {+-} 5 million B{bar B} pairs. They find S{sub {pi}{pi}} = -0.68 {+-} 0.10 {+-} 0.03, C{sub {pi}{pi}} = -0.25 {+-} 0.08 {+-} 0.02, {Alpha}{sub K{sub {pi}}} = -0.107 {+-} 0.016{sub -0.004},{sup +0.006}, C{sub {pi}{sup 0}{pi}{sup 0}} = -0.43 {+-} 0.26 {+-} 0.05, {Beta}(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) = (1.83 {+-} 0.21 {+-} 0.13) x 10{sup -6}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup 0}) = (10.1 {+-} 0.6 {+-} 0.4) x 10{sup -6}, where the first error is statistical and the second is systematic. They observe CP violation with a significance of 6.7{sigma} in B{sup 0} {yields} {pi}{sup -} and 6.1{sigma} in B{sup 0} {yields} K{sup +}{pi}{sup -}. Constraints on the Unitarity Triangle angle {alpha} are determined from the isospin relation between all B {yields} {pi}{pi} rates and asymmetries.

Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, Antimo; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, Bjarne; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, Robert N.; Jacobsen, R.G.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Banca di Roma /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2008-08-01

94

A breathing wormlike chain model on DNA denaturation and bubble: Effects of stacking interactions  

NASA Astrophysics Data System (ADS)

DNA stably exists as a double-stranded structure due to hydrogen-bonding and stacking interactions between bases. The stacking interactions are strengthened when DNA is paired, which results in great enhancement of bending rigidity. We study the effects of this stacking-induced stiffness difference on DNA denaturation and bubble formations. To this end, we model double-stranded DNA as a duplex of two semiflexible chains whose persistence length varies depending on the base-pair distance. Using this model, we perform the Langevin dynamics simulation to examine the characteristics of the denaturation transition and the statistics of the bubbles. We find that the inclusion of the stacking interactions causes the denaturation transition to be much sharper than otherwise. At physiological temperature, the stacking interactions prohibit the initiation of bubble formation but promote bubbles, once grown, to retain the large size.

Kim, Jae-Yeol; Jeon, Jae-Hyung; Sung, Wokyung

2008-02-01

95

A breathing wormlike chain model on DNA denaturation and bubble: effects of stacking interactions.  

PubMed

DNA stably exists as a double-stranded structure due to hydrogen-bonding and stacking interactions between bases. The stacking interactions are strengthened when DNA is paired, which results in great enhancement of bending rigidity. We study the effects of this stacking-induced stiffness difference on DNA denaturation and bubble formations. To this end, we model double-stranded DNA as a duplex of two semiflexible chains whose persistence length varies depending on the base-pair distance. Using this model, we perform the Langevin dynamics simulation to examine the characteristics of the denaturation transition and the statistics of the bubbles. We find that the inclusion of the stacking interactions causes the denaturation transition to be much sharper than otherwise. At physiological temperature, the stacking interactions prohibit the initiation of bubble formation but promote bubbles, once grown, to retain the large size. PMID:18266461

Kim, Jae-Yeol; Jeon, Jae-Hyung; Sung, Wokyung

2008-02-01

96

Single Electron Detection for SLD Crid and Multi - Spectroscopy in Negative Kaon Proton Interactions at 11 Gev/c  

NASA Astrophysics Data System (ADS)

This thesis consists of two independent parts: development of single electron detectors and a pulse finding algorithm for the Cherenkov Ring Imaging Detector (CRID) for the SLD Detector at SLAC; and the analyses of unflavored, light quark meson systems using data from the LASS Spectrometer. The CRID sections describe the design, construction, and testing of the multi-wire-proportional chambers used to measure all three co-ordinates of the conversion of UV Cherenkov photons into single electrons in the CRID drift boxes. The detectors use charge division to measure one of the co-ordinates and were carefully designed and built to provide 1 mm resolution. The software algorithm used for CRID to determine the co-ordinates of signals in the digitized data is also described. The algorithm uses knowledge of the fixed pulse shape to deconvolve the amplifier shape from the data, providing good single pulse resolution and excellent double pulse separation. The spectroscopic analyses are based on data from a 4.1 (nb)^{-1} exposure of the LASS Spectrometer in K^-p interactions at 11 GeV/c. The channels Lambda pi^{+}pi^{-} and Lambdapi^{+ }pi^{-}pi^0 are studied in detail. Brief surveys of Lambda pi^{+}pi^{-} pi^{+}pi^{-} and Lambdapi^{+ }pi^{-}pi^{+ }pi^{-}pi^0 are presented. A partial wave analysis of the pi ^{+}pi^{-} system in the Lambdapi^{+ }pi^{-} channel provides evidence for a spin 1 resonance at about 1.3 GeV/c ^2. A fit of this new state, the rho(1300), gives a mass of 1290_sp {-30}{+20}MeV/c^2 and a width of 120_sp{-50} {+60}MeV/c^2. The elasticity of the rho(1300) is estimated as ~5%. Some evidence of rho(1690) production is seen in the pi^{+}pi^{-} system. A partial wave analysis of the pi ^{-}pi^{0} system produced against a backward-going Sigma ^+(1385) in Lambdapi ^{+}pi^{-}pi ^0 again shows evidence of rho (1300) production, with parameters consistent with the pi^{+}pi^ {-} analysis. The examinations of the 4 pion mass spectra in Lambdapi^{+}pi ^{-}pi^{+}pi ^{-} and Sigma^+ (1385)pi^{+}pi ^{-}pi^{-}pi ^0 do not provide any definite evidence of rho(1300) production. The upper limits on the 4pi to 2pi branching ratios are 3 for the neutral and 6 for the charged system. Data for the K_sp{rm S}{0}K^-, K^+K^-, and {| K}^0K ^{+/-}pi^mp modes previously analysed by LASS are presented with attention to possible contributions from rho(1300). No evidence of rho (1300) is seen.

Rensing, Paul Elliot

97

Study of the D0 ---> pi- pi+ pi- pi+ decay  

SciTech Connect

Using data from the FOCUS (E831) experiment at Fermilab, they present new measurements for the Cabbibo-suppressed decay mode D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}. They measure the branching ratio {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{sup -} {pi}{sup +}{pi}{sup -}{pi}{sup +}) = 0.0914 {+-} 0.0018 {+-} 0.0022. An amplitude analysis has been performed, a first for this channel, in order to determine the resonant substructure of this decay mode. The dominant component is the decay D{sup 0} {yields} a{sub 1}(1260){sup +}{pi}{sup -}, accounting for 60% of the decay rate. The second most dominant contribution comes from the decay D{sup 0} {yields} {rho}(770){sup 0}{rho}(770){sup 0}, with a fraction of 25%. They also study the a{sub 1}(1260) line shape and resonant substructure. Using the helicity formalism for the angular distribution of the decay D{sup 0} {yields} {rho}(770){sup 0}{rho}(770){sup 0}, they measure a longitudinal polarization of P{sub L} = (71 {+-} 4 {+-} 2)%.

Link, J.M.; Yager, P.M.; /UC, Davis; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; /Rio de Janeiro, CBPF /CINVESTAV, IPN /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U.

2007-01-01

98

Search for D0-D0 mixing and branching-ratio measurement in the decay D0-->K+ pi- pi0.  

PubMed

We analyze 230.4 fb;{-1} of data collected with the BABAR detector at the PEP-II e;{+}e;{-} collider at SLAC to search for evidence of D0-D[over ];{0} mixing using regions of phase space in the decay D;{0}-->K;{+}pi;{-}pi;{0}. We measure the time-integrated mixing rate R_{M}=(0.023_{-0.014};{+0.018}(stat.)+/-0.004(syst.))%, and R_{M}<0.054% at the 95% confidence level, assuming CP invariance. The data are consistent with no mixing at the 4.5% confidence level. We also measure the branching ratio for D;{0}-->K;{+}pi;{-}pi;{0} relative to D;{0}-->K;{-}pi;{+}pi;{0} to be (0.214+/-0.008(stat.)+/-0.008(syst.))%. PMID:17155794

Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Chauveau, J; Briand, H; David, P

2006-12-01

99

On the nature of the pi --> pi* ionic excited states: the V state of ethene as a prototype.  

PubMed

This article addresses an analysis of the physical effects required for the correct description of the ionic pi --> pi* excited states in the frame of ab initio quantum chemistry, using the ionic V state of the ethene molecule as an example. The importance of the dynamic sigma polarization (absent in methods where the sigma skeleton is treated at a mean-field level) has been recognized by many authors in the past. In this article a new physical effect is described, i.e. the spatial contraction of the pi and pi* molecular orbitals (or of the local p atomic orbitals) originated from the reduction of the ionicity due to the dynamic sigma polarization. Such an effect is a second-order effect (it appears only as a consequence of the dynamic sigma polarization) but it cannot be ignored. Many of the difficulties found in the past in the calculation of the vertical excitation energy of the ionic states are attributed to an incomplete description of this contraction, while the few successes have been obtained when it has been fortuitously introduced by ad hoc procedures or when it is described in a brute force approach. Various strategies are proposed to allow for the spatial contraction of the p atomic orbitals. If this effect is considered at the orbital optimization step, it is shown that for the V state of ethene no Rydberg/valence mixing occurs and a simple perturbation correction (to the second order in the energy) on the pi --> pi* singly excited configuration gives stable results with respect to the computational parameters and in good agreement with the experimental findings and with the best theoretical calculations. Moreover, our results confirm the indication of Müller et al. (J Chem Phys 1999, 110, 7176) that the transition to the V state of ethene conforms to the Franck-Condon principle and that it is not necessary to appeal to a nonvertical transition to interpret the experimental data. The strategy reported in this article for ethene can be in principle generalized to the pi --> pi* ionic excited states of other molecules. PMID:19009592

Angeli, Celestino

2009-06-01

100

Observation of a broad structure in the pi+ pi- J/psi mass spectrum around 4.26 GeV/c2.  

PubMed

We study initial-state radiation events, e+ e- --> gammaISR pi+ pi- J/psi, with data collected with the BABAR detector. We observe an accumulation of events near 4.26 GeV/c2 in the invariant-mass spectrum of pi+ pi- J/psi. Fits to the mass spectrum indicate that a broad resonance with a mass of about 4.26 GeV/c2 is required to describe the observed structure. The presence of additional narrow resonances cannot be excluded. The fitted width of the broad resonance is 50 to 90 MeV/c2, depending on the fit hypothesis. PMID:16241645

Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Pappagallo, M; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Teodorescu, L; Blinov, A E; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Andreassen, R; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Altenburg, D; Feltresi, E; Hauke, A; Spaan, B; Brandt, T; Brose, J; Dickopp, M; Klose, V; Lacker, H M; Nogowski, R; Otto, S; Petzold, A; Schott, G; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Wu, J; Dubitzky, R S; Langenegger, U; Marks, J; Schenk, S; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Vazquez, W P; Charles, M J; Mader, W F; Mallik, U; Mohapatra, A K; Cochran, J; Crawley, H B; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Petersen, T C; Pierini, M; Plaszczynski, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Parry, R J; Payne, D J; Schofield, K C; Touramanis, C; Cormack, C M; Di Lodovico, F; Menges, W; Sacco, R; Brown, C L; Cowan, G; Flaecher, H U; Green, M G; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Edgar, C L; Hodgkinson, M C; Kelly, M P; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Li, X; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Viaud, B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R

2005-09-30

101

Observation of the Decay B±-->pi±pi0, Study of B±-->K±pi0, and Search for B0-->pi0pi0  

Microsoft Academic Search

We present results for the branching fractions and charge asymmetries in B±-->h±pi0 (where h±=pi±,K±) and a search for the decay B0-->pi0pi0 using a sample of approximately 88×106 BB¯ pairs collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure B(B±-->pi±pi0)=(5.5+1.0-0.9±0.6)×10-6, where the first error is statistical and the second is systematic. The B±-->pi±pi0 signal has

B. Aubert; R. Barate; D. Boutigny; J.-M. Gaillard; A. Hicheur; Y. Karyotakis; J. P. Lees; P. Robbe; V. Tisserand; A. Zghiche; A. Palano; A. Pompili; J. C. Chen; N. D. Qi; G. Rong; P. Wang; Y. S. Zhu; G. Eigen; I. Ofte; B. Stugu; G. S. Abrams; A. W. Borgland; A. B. Breon; D. N. Brown; J. Button-Shafer; R. N. Cahn; E. Charles; M. S. Gill; A. V. Gritsan; Y. Groysman; R. G. Jacobsen; R. W. Kadel; J. Kadyk; L. T. Kerth; Yu. G. Kolomensky; J. F. Kral; G. Kukartsev; C. Leclerc; M. E. Levi; G. Lynch; L. M. Mir; P. J. Oddone; T. J. Orimoto; M. Pripstein; N. A. Roe; A. Romosan; M. T. Ronan; V. G. Shelkov; A. V. Telnov; W. A. Wenzel; T. J. Harrison; C. M. Hawkes; D. J. Knowles; R. C. Penny; A. T. Watson; N. K. Watson; T. Deppermann; K. Goetzen; H. Koch; B. Lewandowski; M. Pelizaeus; K. Peters; H. Schmuecker; M. Steinke; N. R. Barlow; W. Bhimji; J. T. Boyd; N. Chevalier; P. J. Clark; W. N. Cottingham; C. Mackay; F. F. Wilson; C. Hearty; T. S. Mattison; J. A. McKenna; D. Thiessen; P. Kyberd; A. K. McKemey; V. E. Blinov; A. D. Bukin; V. B. Golubev; V. N. Ivanchenko; E. A. Kravchenko; A. P. Onuchin; S. I. Serednyakov; Yu. I. Skovpen; E. P. Solodov; A. N. Yushkov; D. Best; M. Chao; D. Kirkby; A. J. Lankford; M. Mandelkern; S. McMahon; R. K. Mommsen; W. Roethel; D. P. Stoker; C. Buchanan; H. K. Hadavand; E. J. Hill; D. B. Macfarlane; H. P. Paar; Sh. Rahatlou; U. Schwanke; V. Sharma; J. W. Berryhill; C. Campagnari; B. Dahmes; N. Kuznetsova; S. L. Levy; O. Long; A. Lu; M. A. Mazur; J. D. Richman; W. Verkerke; J. Beringer; A. M. Eisner; C. A. Heusch; W. S. Lockman; T. Schalk; R. E. Schmitz; B. A. Schumm; A. Seiden; M. Turri; W. Walkowiak; D. C. Williams; M. G. Wilson; J. Albert; E. Chen; G. P. Dubois-Felsmann; A. Dvoretskii; D. G. Hitlin; I. Narsky; F. C. Porter; A. Ryd; A. Samuel; S. Yang; S. Jayatilleke; G. Mancinelli; B. T. Meadows; M. D. Sokoloff; T. Barillari; F. Blanc; P. Bloom; W. T. Ford; U. Nauenberg; A. Olivas; P. Rankin; J. Roy; J. G. Smith; W. C. van Hoek; L. Zhang; J. L. Harton; T. Hu; A. Soffer; W. H. Toki; R. J. Wilson; J. Zhang; D. Altenburg; T. Brandt; J. Brose; T. Colberg; M. Dickopp; R. S. Dubitzky; A. Hauke; H. M. Lacker; E. Maly; R. Müller-Pfefferkorn; R. Nogowski; S. Otto; K. R. Schubert; R. Schwierz; B. Spaan; L. Wilden; D. Bernard; G. R. Bonneaud; F. Brochard; J. Cohen-Tanugi; S. T'jampens; Ch. Thiebaux; G. Vasileiadis; M. Verderi; R. Bernet; A. Khan; D. Lavin; F. Muheim; S. Playfer; J. E. Swain; J. Tinslay; C. Borean; C. Bozzi; L. Piemontese; A. Sarti; E. Treadwell; F. Anulli; R. Baldini-Ferroli; A. Calcaterra; R. de Sangro; D. Falciai; G. Finocchiaro; P. Patteri; I. M. Peruzzi; M. Piccolo; A. Zallo; A. Buzzo; R. Contri; G. Crosetti; M. Lo Vetere; M. Macri; M. R. Monge; S. Passaggio; F. C. Pastore; C. Patrignani; E. Robutti; A. Santroni; S. Tosi; S. Bailey; M. Morii; G. J. Grenier; S.-J. Lee; U. Mallik; J. Cochran; H. B. Crawley; J. Lamsa; W. T. Meyer; S. Prell; E. I. Rosenberg; J. Yi; M. Davier; G. Grosdidier; A. Höcker; S. Laplace; F. Le Diberder; V. Lepeltier; A. M. Lutz; T. C. Petersen; S. Plaszczynski; M. H. Schune; L. Tantot; G. Wormser; R. M. Bionta; V. Brigljevic; C. H. Cheng; D. J. Lange; D. M. Wright; A. J. Bevan; J. R. Fry; E. Gabathuler; R. Gamet; M. Kay; D. J. Payne; R. J. Sloane; C. Touramanis; M. L. Aspinwall; D. A. Bowerman; P. D. Dauncey; U. Egede; I. Eschrich; G. W. Morton; J. A. Nash; P. Sanders; G. P. Taylor; J. J. Back; G. Bellodi; P. F. Harrison; H. W. Shorthouse; P. Strother; P. B. Vidal; G. Cowan; H. U. Flaecher; S. George; M. G. Green; A. Kurup; C. E. Marker; T. R. McMahon; S. Ricciardi; F. Salvatore; G. Vaitsas; M. A. Winter; C. L. Davis; J. Allison; R. J. Barlow; A. C. Forti; P. A. Hart; F. Jackson; G. D. Lafferty; A. J. Lyon; J. H. Weatherall; J. C. Williams; A. Farbin; A. Jawahery; D. Kovalskyi; C. K. Lae; V. Lillard; D. A. Roberts; G. Blaylock; C. Dallapiccola; K. T. Flood; S. S. Hertzbach; R. Kofler; V. B. Koptchev; T. B. Moore; H. Staengle; S. Willocq; R. Cowan; G. Sciolla; F. Taylor; R. K. Yamamoto; D. J. Mangeol; M. Milek; P. M. Patel; F. Palombo; J. M. Bauer; L. Cremaldi; V. Eschenburg; R. Kroeger; J. Reidy; D. A. Sanders; D. J. Summers; H. W. Zhao; C. Hast; P. Taras; H. Nicholson; C. Cartaro; N. Cavallo; G. de Nardo; F. Fabozzi; C. Gatto; L. Lista; P. Paolucci; D. Piccolo; C. Sciacca; M. A. Baak; G. Raven; J. M. Losecco; T. A. Gabriel; B. Brau; T. Pulliam; J. Brau; R. Frey; M. Iwasaki; C. T. Potter; N. B. Sinev; D. Strom; E. Torrence; F. Colecchia; A. Dorigo; F. Galeazzi; M. Margoni; M. Morandin; M. Posocco; M. Rotondo; F. Simonetto; R. Stroili; G. Tiozzo; C. Voci; M. Benayoun; H. Briand; J. Chauveau; P. David; Ch. de La Vaissière; L. del Buono; O. Hamon; Ph. Leruste; J. Ocariz; M. Pivk; L. Roos; J. Stark; P. F. Manfredi; V. Re; L. Gladney; Q. H. Guo; J. Panetta; C. Angelini; G. Batignani; S. Bettarini; M. Bondioli

2003-01-01

102

Theoretical investigation of the stacking interactions between curved conjugated systems and their interaction with fullerenes  

NASA Astrophysics Data System (ADS)

Herein, we perform a M06-2X/6-311G investigation of the homo and mixed dimers formed between corannulene, sumanene, and pentaindenocorannulene; also, their complexes with C 60 and C 70 were studied. Despite the lower area of sumanene, the interaction of the sumanene-dimer is stronger that of the corannulene-dimer because of CH-? interactions. For mixed-dimers, when the concave and convex sides perfectly match the interactions are similar to those of the homodimers. However, when the concave area is larger than the convex one, CH-? interactions become important and perfect stacking is lost. The interaction between pentaindenocorannulene-C 60 is twice that of corannulene-C 60, and ? G298 = -10.8 kcal/mol. Thus, pentaindenocorannulene is a better choice to catch C 60.

Denis, Pablo A.

2011-11-01

103

Search for CP Violation in the Decays D0 to K- K+and D0 to pi- pi+  

SciTech Connect

We measure CP-violating asymmetries of neutral charmed mesons in the modes D{sup 0} {yields} K{sup -}K{sup +} and D{sup 0} {yields} {pi}{sup -}{pi}{sup +} with the highest precision to date by using D{sup 0} {yields} K{sup -}{pi}{sup +} decays to correct detector asymmetries. An analysis of 385.8 fb{sup -}1 of data collected with the BaBar detector yields values of a{sup KK}{sub CP} = (0.00 {+-} 0.34 (stat.) {+-} 0.13 (syst.))% and a{sup {pi}{pi}}{sub CP} = (-0.24 {+-} 0.52 (stat.) {+-} 0.22 (syst.))%, which agree with Standard Model predictions.

Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

2007-09-24

104

Measurement of partial widths and search for direct CP violation in D0 meson decays to K-K+ and pi-pi+.  

PubMed

We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and pi(-)pi(+) decays of D0 mesons produced in pp collisions at sqrt[s]=1.96 TeV. We use a sample of 2x10(5) D(*+)-->D0pi(+) (and charge conjugate) decays with the D0 decaying to K-pi(+), K-K+, and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D0-->K-K+)/Gamma(D0-->K-pi(+))=0.0992+/-0.0011+/-0.0012, Gamma(D0-->pi(-)pi(+))/Gamma(D0-->K-pi(+))=0.035 94+/-0.000 54+/-0.000 40, A(CP)(K-K+)=(2.0+/-1.2+/-0.6)%, and A(CP)(pi(-)pi(+))=(1.0+/-1.3+/-0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic. PMID:15903906

Acosta, D; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J-F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bolla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Calafiura, P; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Cavalli-Sforza, M; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerri, C; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chu, M L; Chuang, S; Chung, J Y; Chung, W-H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cooper, B; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; de Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'agnello, S; Dell'orso, M; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; Doksus, P; Dominguez, A; Donati, S; Donega, M; Donini, J; D'Onofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H-C; Farrington, S; Fedorko, I; Feild, R G; Feindt, M; Fernandez, J P; Ferretti, C; Field, R D; Fiori, I; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J; Frisch, H; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; Garcia-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grosso-Pilcher, C; Guenther, M; Guimaraes da Costa, J; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Hocker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S; Junk, T; Kamon, T; Kang, J; Karagoz Unel, M; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Konigsberg, J; Kordas, K; Korn, A; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kuznetsova, N; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; Lecompte, T; Lee, J; Lee, J; Lee, S W; Leonardo, N; Leone, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lyons, L; Lys, J; Lysak, R; Macqueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Martin, M; Martin, A; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; Ncnulty, R; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Mukherjee, A; Mulhearn, M; Muller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nicollerat, A-S; Nigmanov, T; Nodulman, L; Norniella, O; Oesterberg, K; Ogawa, T; Oh, S H; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R; Orava, R; Orejudos, W; Pagliarone, C

2005-04-01

105

From (pi,0) magnetic order to superconductivity with (pi,pi) magnetic resonance in Fe(1.02)Te(1-x)Se(x).  

PubMed

The iron chalcogenide Fe(1+y)(Te(1-x)Se(x)) is structurally the simplest of the Fe-based superconductors. Although the Fermi surface is similar to iron pnictides, the parent compound Fe(1+y)Te exhibits antiferromagnetic order with an in-plane magnetic wave vector (pi,0) (ref. 6). This contrasts the pnictide parent compounds where the magnetic order has an in-plane magnetic wave vector (pi,pi) that connects hole and electron parts of the Fermi surface. Despite these differences, both the pnictide and chalcogenide Fe superconductors exhibit a superconducting spin resonance around (pi,pi) (refs 9, 10, 11). A central question in this burgeoning field is therefore how (pi,pi) superconductivity can emerge from a (pi,0) magnetic instability. Here, we report that the magnetic soft mode evolving from the (pi,0)-type magnetic long-range order is associated with weak charge carrier localization. Bulk superconductivity occurs as magnetic correlations at (pi,0) are suppressed and the mode at (pi, pi) becomes dominant for x>0.29. Our results suggest a common magnetic origin for superconductivity in iron chalcogenide and pnictide superconductors. PMID:20639892

Liu, T J; Hu, J; Qian, B; Fobes, D; Mao, Z Q; Bao, W; Reehuis, M; Kimber, S A J; Prokes, K; Matas, S; Argyriou, D N; Hiess, A; Rotaru, A; Pham, H; Spinu, L; Qiu, Y; Thampy, V; Savici, A T; Rodriguez, J A; Broholm, C

2010-09-01

106

High statistics study of the reaction pip>pi-pi+n: Apparatus, method of analysis, and general features of results at 17 GeV\\/c  

Microsoft Academic Search

A detailed account is given of a high statistics experiment measuring the reaction pi-p-->pi-pi+n at 17.2 GeV\\/c. The spark chamber and counter triggering system are desribed. The methods of data analysis are described, in particular the determination of angular distributions from apparatus with limited acceptance. Experimental data and their interpretation are presented.

G. Grayer; B. Hyams; C. Jones; P. Schlein; P. Weilhammer; W. Blum; H. Dietl; W. Koch; E. Lorenz; G. Lütjens; W. Männer; J. Meissburger; W. Ochs; U. Stierlin

1974-01-01

107

Structure and intermolecular interactions of glipizide from laboratory X-ray powder diffraction.  

PubMed

The crystal structure of glipizide, used as a major treatment of type-2 diabetes, has been determined ab initio using variable-temperature laboratory X-ray powder diffraction combined with a direct-space Monte Carlo/simulated annealing methodology. The strengths of the intermolecular interactions (van der Waals, pi-pi stacking, hydrogen bonding and steric interlock) were quantitatively estimated using the thermal expansion data, which were collected in the same set of experiments as those used to determine the structure. PMID:16306678

Burley, Jonathan C

2005-12-01

108

Molecular aggregation in soluble phthalocyanines - Chemical interactions vs. ?-stacking  

NASA Astrophysics Data System (ADS)

Aggregation of soluble sulfonated phthalocyanines (Pcs) containing di- and trivalent central atoms in binary water-alcohol solvents has been studied. The equilibrium constants of dimerization in solutions of Pcs with divalent central atoms (Zn, Cu) were found dependent on the electrical permittivity of the solvent and on the degree of sulfonation (i.e., on the charge on the phthalocyanine anions). Our results show that in Pcs with the trivalent central atom (Al(OH)) the dimerization occurs preferentially by formation of oxygen bridges or hydrogen bonds. Disulfonated aluminum phthalocyanine anions dissolved in water-rich binary solvents seem to form both ?-stacked dimers and chemical dimers, due to a decrease in the Coulombic repulsive energy. The experiments reported in the paper indicate that the aggregation of soluble phthalocyanines can be controlled by the choice of a suitable electric permittivity of the solvent.

Palewska, Krystyna; Sworakowski, Juliusz; Lipi?ski, Józef

2012-08-01

109

Measurement of the E+ E- to Pi+ Pi- (Gamma) Cross Section with the ISR Method with BaBar  

SciTech Connect

A precision measurement of the cross section for the process e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -}({gamma}) is presented with the radiative return method with the high statistics data accumulated by BaBar at the {Upsilon}(4S). The luminosity is determined from the study of the corresponding leptonic process e{sup +}e{sup -} {yields} {mu}{sup +}{mu}{sup -}({gamma}), thus cancelling several factors and reducing the overall systematic uncertainty. Trigger, tracking, particle identification, and kinematic-fit {chi}{sup 2} efficiencies are evaluated from data in the same environment. Additional radiation from the initial and the final states is studied in both processes. The analysis covers the mass range between threshold and 5 GeV. Preliminary results are presented here between 0.5 and 3 GeV, with data samples of 513183 pion events and 445631 muon events. The systematic uncertainty in the main {rho} resonance region is 5.6 x 10{sup -3}. The measured mass dependent pion-pair cross section is compared with measurements from earlier experiments and used to compute the hadronic vacuum polarization contribution from the dominant {pi}{pi} channel to the muon magnetic anomaly.

Davier, Michel; /Orsay, LAL

2011-11-30

110

Lipophilic Isosteres of a ?-? Stacking Interaction: New Inhibitors of the Bcl-2-Bak Protein-Protein Interaction  

PubMed Central

The discovery of new Bcl-2 protein–protein interaction antagonists is described. We replaced the northern fragment of ABT737 (?–? stacking interactions) with structurally simplified hydrophobic cage structures with much reduced conformational flexibility and rotational freedom. The binding mode of the compounds was elucidated by X-ray crystallography, and the compounds showed excellent oral bioavailability and clearance in rat PK studies.

2012-01-01

111

Study of the B>J\\/psiK-pi+pi- decay and measurement of the B>X(3872)K- branching fraction  

Microsoft Academic Search

We study the decay B--->J\\/psiK-pi+pi- using 117×106 BB¯ events collected at the Y(4S) resonance with the BABAR detector at the PEP-II e+e- asymmetric-energy storage ring. We measure the branching fractions B (B--->J\\/psiK-pi+pi-)=(116±7(stat.)±9(syst.))×10-5 and B (B--->X(3872)K-)× B (X(3872)-->J\\/psipi+pi-)=(1.28±0.41)×10-5 and find the mass of the X(3872) to be 3873.4±1.4 MeV\\/c2. We search for the hc narrow state in the decay B--->hcK-, hc-->J\\/psipi+pi-

B. Aubert; R. Barate; D. Boutigny; F. Couderc; J.-M. Gaillard; A. Hicheur; Y. Karyotakis; J. P. Lees; V. Tisserand; A. Zghiche; A. Palano; A. Pompili; J. C. Chen; N. D. Qi; G. Rong; P. Wang; Y. S. Zhu; G. Eigen; I. Ofte; B. Stugu; G. S. Abrams; A. W. Borgland; A. B. Breon; D. Brown; J. Button-Shafer; R. N. Cahn; E. Charles; C. T. Day; M. S. Gill; A. V. Gritsan; Y. Groysman; R. G. Jacobsen; R. W. Kadel; J. Kadyk; L. T. Kerth; Yu. G. Kolomensky; G. Kukartsev; C. Leclerc; G. Lynch; A. M. Merchant; L. M. Mir; P. J. Oddone; T. J. Orimoto; M. Pripstein; N. A. Roe; M. T. Ronan; V. G. Shelkov; W. A. Wenzel; K. Ford; T. J. Harrison; C. M. Hawkes; S. E. Morgan; A. T. Watson; M. Fritsch; K. Goetzen; T. Held; H. Koch; B. Lewandowski; M. Pelizaeus; M. Steinke; J. T. Boyd; N. Chevalier; W. N. Cottingham; M. P. Kelly; T. E. Latham; F. F. Wilson; T. Cuhadar-Donszelmann; C. Hearty; N. S. Knecht; T. S. Mattison; J. A. McKenna; D. Thiessen; A. Khan; P. Kyberd; L. Teodorescu; V. E. Blinov; A. D. Bukin; V. P. Druzhinin; V. B. Golubev; V. N. Ivanchenko; E. A. Kravchenko; A. P. Onuchin; S. I. Serednyakov; Yu. I. Skovpen; E. P. Solodov; A. N. Yushkov; D. Best; M. Bruinsma; M. Chao; I. Eschrich; D. Kirkby; A. J. Lankford; M. Mandelkern; R. K. Mommsen; W. Roethel; D. P. Stoker; C. Buchanan; B. L. Hartfiel; J. W. Gary; B. C. Shen; K. Wang; D. del Re; H. K. Hadavand; E. J. Hill; D. B. Macfarlane; H. P. Paar; Sh. Rahatlou; V. Sharma; J. W. Berryhill; C. Campagnari; B. Dahmes; S. L. Levy; O. Long; A. Lu; M. A. Mazur; J. D. Richman; W. Verkerke; T. W. Beck; A. M. Eisner; C. A. Heusch; W. S. Lockman; T. Schalk; R. E. Schmitz; B. A. Schumm; A. Seiden; P. Spradlin; D. C. Williams; M. G. Wilson; J. Albert; E. Chen; G. P. Dubois-Felsmann; A. Dvoretskii; D. G. Hitlin; I. Narsky; T. Piatenko; F. C. Porter; A. Ryd; A. Samuel; S. Yang; S. Jayatilleke; G. Mancinelli; B. T. Meadows; M. D. Sokoloff; T. Abe; F. Blanc; P. Bloom; S. Chen; W. T. Ford; U. Nauenberg; A. Olivas; P. Rankin; J. G. Smith; J. Zhang; L. Zhang; A. Chen; J. L. Harton; A. Soffer; W. H. Toki; R. J. Wilson; Q. L. Zeng; D. Altenburg; T. Brandt; J. Brose; T. Colberg; M. Dickopp; E. Feltresi; A. Hauke; H. M. Lacker; E. Maly; R. Müller-Pfefferkorn; R. Nogowski; S. Otto; A. Petzold; J. Schubert; K. R. Schubert; R. Schwierz; B. Spaan; J. E. Sundermann; D. Bernard; G. R. Bonneaud; F. Brochard; P. Grenier; S. Schrenk; Ch. Thiebaux; G. Vasileiadis; M. Verderi; D. J. Bard; P. J. Clark; D. Lavin; F. Muheim; S. Playfer; Y. Xie; M. Andreotti; V. Azzolini; D. Bettoni; C. Bozzi; R. Calabrese; G. Cibinetto; E. Luppi; M. Negrini; L. Piemontese; A. Sarti; E. Treadwell; R. Baldini-Ferroli; A. Calcaterra; R. de Sangro; G. Finocchiaro; P. Patteri; M. Piccolo; A. Zallo; A. Buzzo; R. Capra; R. Contri; G. Crosetti; M. Lo Vetere; M. Macri; M. R. Monge; S. Passaggio; C. Patrignani; E. Robutti; A. Santroni; S. Tosi; S. Bailey; G. Brandenburg; M. Morii; E. Won; R. S. Dubitzky; U. Langenegger; W. Bhimji; D. A. Bowerman; P. D. Dauncey; U. Egede; J. R. Gaillard; G. W. Morton; J. A. Nash; G. P. Taylor; G. J. Grenier; U. Mallik; J. Cochran; H. B. Crawley; J. Lamsa; W. T. Meyer; S. Prell; E. I. Rosenberg; J. Yi; M. Davier; G. Grosdidier; A. Höcker; S. Laplace; F. Le Diberder; V. Lepeltier; A. M. Lutz; T. C. Petersen; S. Plaszczynski; M. H. Schune; L. Tantot; G. Wormser; C. H. Cheng; D. J. Lange; M. C. Simani; D. M. Wright; A. J. Bevan; J. P. Coleman; J. R. Fry; E. Gabathuler; R. Gamet; R. J. Parry; D. J. Payne; R. J. Sloane; C. Touramanis; J. J. Back; C. M. Cormack; P. F. Harrison; G. B. Mohanty; C. L. Brown; G. Cowan; R. L. Flack; H. U. Flaecher; M. G. Green; C. E. Marker; T. R. McMahon; S. Ricciardi; F. Salvatore; G. Vaitsas; M. A. Winter; C. L. Davis; J. Allison; N. R. Barlow; R. J. Barlow; P. A. Hart; M. C. Hodgkinson; G. D. Lafferty; A. J. Lyon; J. C. Williams; A. Farbin; W. D. Hulsbergen; A. Jawahery; D. Kovalskyi; C. K. Lae; V. Lillard; D. A. Roberts; G. Blaylock; C. Dallapiccola; K. T. Flood; S. S. Hertzbach; R. Kofler; V. B. Koptchev; T. B. Moore; S. Saremi; H. Staengle; S. Willocq; R. Cowan; G. Sciolla; F. Taylor; R. K. Yamamoto; D. J. Mangeol; P. M. Patel; S. H. Robertson; A. Lazzaro; F. Palombo; J. M. Bauer; L. Cremaldi; V. Eschenburg; R. Godang; R. Kroeger; J. Reidy; D. A. Sanders; D. J. Summers; H. W. Zhao; S. Brunet; D. Côté; P. Taras; H. Nicholson; N. Cavallo; F. Fabozzi; C. Gatto; L. Lista; D. Monorchio; P. Paolucci; D. Piccolo; C. Sciacca; M. Baak; H. Bulten; G. Raven; L. Wilden; C. P. Jessop; J. M. Losecco; T. A. Gabriel; T. Allmendinger; B. Brau; K. K. Gan; K. Honscheid; D. Hufnagel; H. Kagan; R. Kass; T. Pulliam; A. M. Rahimi; R. Ter-Antonyan; Q. K. Wong; J. Brau; R. Frey; O. Igonkina; C. T. Potter; N. B. Sinev; D. Strom; E. Torrence; F. Colecchia; A. Dorigo; F. Galeazzi; M. Margoni; M. Morandin; M. Posocco; M. Rotondo; F. Simonetto

2005-01-01

112

Interactions between stacked layers of phenyl-modified silicene  

NASA Astrophysics Data System (ADS)

We use density functional theory (DFT) calculations to determine the interaction between phenyl-modified silicene nanosheets. The adhesion energy curves between the nanosheets are compared for different van der Waals density functional (vdW-DF) functionals and the DFT-D2 Grimme method. Our results show that there is a weak attraction between the sheets at close separations, that is stronger when vdWs forces are included. Without including vdWs forces the interaction is negligible and occurs at a much larger separation, highlighting the need to include such forces when modelling these nanosheets. Of the vdWs methods, the optB88 functional gives the strongest interaction energy while the Grimme gives the weakest, with the separation at which the nanosheets adhere more strongly varying between 10.04 and 11.24 Å, as measured by the distance between the silicene layers. As the modified nanosheets are brought closer together at separations as close at ˜ 8 Å, the phenyl groups on the bottom of one nanosheet can fit in between the phenyl groups on the top of the adjacent nanosheet allowing some ? - ? interaction between the phenyl groups. We showed that the band gap can be modified by compressing the nanosheets together while retaining a small attraction between them. There is also a change from a direct to an indirect band gap. Such a property may be exploited for the application of these nanomaterials in optoelectronic devices.

Spencer, Michelle J. S.; Bassett, Michael R.; Morishita, Tetsuya; Snook, Ian K.; Nakano, Hideyuki

2013-12-01

113

Pi-Pi complexation of bupivacaine and analogues with aromatic receptors: Implications for overdose remediation  

PubMed Central

The interaction of the important but often overdosed local anesthetic bupivacaine, its structural analogs 2,6-dimethylaniline, and N-methyl-2,6-dimethylacetanilide, and cocaine, with several electron deficient aromatic moieties were studied primarily by proton NMR and UV-visible spectroscopy. In solution, the anesthetic, its analogs and cocaine are electron donors and form ?-? charge transfer complexes with strong aromatic acceptors, as monitored by the upfield changes induced in the NMR chemical shifts (?) and red-shifted UV-vis wavelength (?max) absorbance of the acceptors. The equilibrium binding constant, K, was determined from the 1H NMR charge transfer induced chemical shift changes and used to calculate the free energy (?G) for complex formation of three acceptor-donor pairs. HPLC results indicate that the concentrations of free bupivacaine, its analogs and of cocaine are reduced from solution via binding to aromatic-functionalized silica.

Powell, Evon; Lee, Y-H; Partch, Richard; Dennis, Donn; Morey, Timothy; Varshney, Manoj

2007-01-01

114

Determination of weak phases $\\\\phi_2$ and $\\\\phi_3$ from $B\\\\to \\\\pi\\\\pi,K\\\\pi$ in the pQCD method  

Microsoft Academic Search

We look at two methods to determine the weak phases $\\\\phi_2$ and $\\\\phi_3$ from $B \\\\to \\\\pi\\\\pi$ and $K\\\\pi$ decays within the perturbative QCD approach. We obtain quite interesting bounds on $\\\\phi_2$ and $\\\\phi_3$ from recent experimental measurements in asymmetric B-factory: $55^o \\\\leq \\\\phi_2 \\\\leq 100^o$ and $51^o \\\\leq \\\\phi_3 \\\\leq 129^o$. Specially we predict the possibility of large direct

Yong-Yeon Keum

2002-01-01

115

Chiral dynamics of the {lambda}(1520) in coupled channels tested in the K-p {yields} {pi}{pi}{lambda} reaction  

SciTech Connect

The {lambda}(1520) resonance is generated dynamically in a unitary coupled channel framework with the {pi}{sigma}* and K{xi}* channels in s-wave and {pi}{sigma} and K-barN channels in d-wave. The dynamics of this resonance close to and above threshold is then tested through the reactions K- p {yields} {pi}{pi}{lambda} and a good agreement with the experimentally measured cross section is observed.

Sarkar, Sourav; Roca, L.; Oset, E.; Magas, V. K.; Vacas, M. J. Vicente [Departamento de Fisica Teorica, Centra Mixto Universidad de Valencia-CSIC, Investigation de Paterna, Aptdo. 22085, 46071 Valencia (Spain); IFIC, Centra Mixto Universidad de Valencia-CSIC, Investigation de Paterna, Aptdo. 22085, 46071 Valencia (Spain)

2006-07-11

116

Role of Multi-Ion Interactions in the Stacking-Fault Energies of Transition Metals.  

National Technical Information Service (NTIS)

The theory of multi-ion interactions is applied to calculations of the stacking-fault energies of transition metals. It is found that observed trends in the stabilities of close-packed transition metals can be explained on the basis of a simple model in w...

R. E. Beissner

1976-01-01

117

Intercalation of daunomycin into stacked DNA base pairs. DFT study of an anticancer drug.  

PubMed

We have computationally studied the intercalation of the antitumor drug daunomycin into six stacks of Watson-Crick DNA base pairs (i.e., AT-AT, AT-TA, GC-AT, CG-TA, GC-GC, GC-CG) using density functional theory (DFT). The proton affinity of the DNA intercalator daunomycin in water was computed to be 159.2 kcal/mol at BP86/TZ2P, which is in line with the experimental observation that daunomycin is protonated under physiological conditions. The intercalation interaction of protonated daunomycin with two stacked DNA base pairs was studied through a hybrid approach in which intercalation is treated at LDA/TZP while the molecular structure of daunomycin and hydrogen-bonded Watson-Crick pairs is computed at BP86/TZ2P. We find that the affinity of the drug for the six considered base pair dimers decreases in the order AT-AT > AT-TA > GC-AT > GC-TA > GC-CG > GC-GC, in excellent agreement with experimental data on the thermodynamics of the interaction between daunomycin and synthetic polynucleotides in aqueous solution. Our analyses show that the overall stability of the intercalation complexes comes mainly from pi-pi stacking but an important contribution to the computed and experimentally observed sequence specificity comes from hydrogen bonding between daunomycin and hetero atoms in the minor groove of AT base pairs. PMID:18533732

Barone, G; Guerra, C F; Gambino, N; Silvestri, A; Lauria, A; Almerico, A M; Bickelhaupt, F M

2008-08-01

118

The influence of arene-ring size on stacking interaction with canonical base pairs  

NASA Astrophysics Data System (ADS)

Stacking interactions between aromatic molecules (benzene, p-cymene, biphenyl, and di- and tetra-hydrogen anthracene) and G.C and A.T canonical Watson-Crick (WC) base pairs are explored. Two functionals with dispersion corrections: ?-B97XD and B3LYP-D3 are used. For a comparison also the MP2 and B3LYP-D3/PCM methods were used for the most stable p-cymene…WC geometries. It was found that the stacking interaction increases with the size of ?-conjugation system. Its extent is in agreement with experimental finding on anticancer activity of Ru(II) piano-stool complexes where intercalation of these aromatic molecules should play an important role. The explored structures are considered as ternary system so that decomposition of the interaction energy to pairwise and non-additivity contributions is also examined.

Formánek, Martin; Burda, Jaroslav V.

2014-04-01

119

Stack zooming for multifocus interaction in skewed-aspect visual spaces.  

PubMed

Many 2D visual spaces have a virtually one-dimensional nature with very high aspect ratio between the dimensions: examples include time-series data, multimedia data such as sound or video, text documents, and bipartite graphs. Common among these is that the space can become very large, e.g., temperature measurements could span a long time period, surveillance video could cover entire days or weeks, and documents can have thousands of pages. Many analysis tasks for such spaces require several foci while retaining context and distance awareness. In this extended version of our IEEE PacificVis 2010 paper, we introduce a method for supporting this kind of multifocus interaction that we call stack zooming. The approach is based on building hierarchies of 1D strips stacked on top of each other, where each subsequent stack represents a higher zoom level, and sibling strips represent branches in the exploration. Correlation graphics show the relation between stacks and strips of different levels, providing context and distance awareness for the foci. The zoom hierarchies can also be used as graphical histories and for communicating insights to stakeholders and can be further extended with annotation and integrated statistics. PMID:23744266

Javed, Waqas; Elmqvist, Niklas

2013-08-01

120

Interplay between halogen bonds and ?-? stacking interactions: CSD search and theoretical study.  

PubMed

According to our survey of the Cambridge Structural Database (CSD), a great number of crystal structures, in which halogen bonds and aromatic stacking interactions are present and play an important role in crystal packing, have been extracted. In this work, ab initio calculations at the MP2 level of theory were performed to investigate the mutual influence between halogen bonds and ?-? stacking interactions. Different energetic effects are observed in the studied complexes where the two kinds of noncovalent interactions coexist, which can be rationalized by the direction of charge transfer for the two interactions. These effects have been analyzed in detail in terms of the structural, energetic, and charge transfer properties of the complexes. In addition, the quantum theory of atoms in molecules (QTAIM) was also employed to characterize the interactions and to examine the strengthening or weakening of the interactions, depending on the variations of electron density on the bond and cage critical points. Finally, certain crystal structures retrieved from the CSD have been selected to provide experimental evidence of the combination of the two interactions. PMID:22710562

Li, Haiying; Lu, Yunxiang; Liu, Yingtao; Zhu, Xiang; Liu, Honglai; Zhu, Weiliang

2012-07-28

121

Measurement of D0-D¯0 Mixing from a Time-Dependent Amplitude Analysis of D0-->K+pi-pi0 Decays  

Microsoft Academic Search

We present evidence of D0-D¯0 mixing using a time-dependent amplitude analysis of the decay D0-->K+pi-pi0 in a data sample of 384fb-1 collected with the BABAR detector at the PEP-II e+e- collider at the Stanford Linear Accelerator Center. Assuming CP conservation, we measure the mixing parameters xKpipi0'=[2.61-0.68+0.57(stat)±0.39(syst)]%, yKpipi0'=[-0.06-0.64+0.55(stat)±0.34(syst)]%. This result is inconsistent with the no-mixing hypothesis with a significance of 3.2

B. Aubert; M. Bona; Y. Karyotakis; J. P. Lees; V. Poireau; E. Prencipe; X. Prudent; V. Tisserand; J. Garra Tico; E. Grauges; L. Lopezab; A. Palanoab; M. Pappagalloab; G. Eigen; B. Stugu; L. Sun; G. S. Abrams; M. Battaglia; D. N. Brown; R. N. Cahn; R. G. Jacobsen; L. T. Kerth; Yu. G. Kolomensky; G. Lynch; I. L. Osipenkov; M. T. Ronan; K. Tackmann; T. Tanabe; C. M. Hawkes; N. Soni; A. T. Watson; H. Koch; T. Schroeder; D. Walker; D. J. Asgeirsson; B. G. Fulsom; C. Hearty; T. S. Mattison; J. A. McKenna; M. Barrett; A. Khan; V. E. Blinov; A. D. Bukin; A. R. Buzykaev; V. P. Druzhinin; V. B. Golubev; A. P. Onuchin; S. I. Serednyakov; Yu. I. Skovpen; E. P. Solodov; K. Yu. Todyshev; M. Bondioli; S. Curry; I. Eschrich; D. Kirkby; A. J. Lankford; P. Lund; M. Mandelkern; E. C. Martin; D. P. Stoker; S. Abachi; C. Buchanan; J. W. Gary; F. Liu; O. Long; B. C. Shen; G. M. Vitug; Z. Yasin; L. Zhang; V. Sharma; C. Campagnari; T. M. Hong; D. Kovalskyi; M. A. Mazur; J. D. Richman; T. W. Beck; A. M. Eisner; C. J. Flacco; C. A. Heusch; J. Kroseberg; W. S. Lockman; T. Schalk; B. A. Schumm; A. Seiden; L. O. Winstrom; M. G. Wilson; C. H. Cheng; D. A. Doll; B. Echenard; F. Fang; D. G. Hitlin; I. Narsky; T. Piatenko; F. C. Porter; R. Andreassen; G. Mancinelli; B. T. Meadows; K. Mishra; M. D. Sokoloff; P. C. Bloom; W. T. Ford; A. Gaz; J. F. Hirschauer; M. Nagel; U. Nauenberg; J. G. Smith; K. A. Ulmer; S. R. Wagner; R. Ayad; A. Soffer; W. H. Toki; R. J. Wilson; D. D. Altenburg; E. Feltresi; A. Hauke; H. Jasper; M. Karbach; J. Merkel; A. Petzold; B. Spaan; K. Wacker; M. J. Kobel; W. F. Mader; R. Nogowski; K. R. Schubert; R. Schwierz; J. E. Sundermann; A. Volk; D. Bernard; G. R. Bonneaud; E. Latour; Ch. Thiebaux; M. Verderi; P. J. Clark; W. Gradl; S. Playfer; J. E. Watson; M. Andreotti; D. Bettoni; C. Bozzi; R. Calabrese; A. Cecchi; G. Cibinetto; P. Franchini; E. Luppi; M. Negrini; A. Petrella; L. Piemontese; V. Santoro; R. Baldini-Ferroli; A. Calcaterra; R. de Sangro; G. Finocchiaro; S. Pacetti; P. Patteri; I. M. Peruzzi; M. Piccolo; M. Rama; A. Zallo; A. Buzzo; R. Contri; M. Lo Vetere; M. M. Macri; M. R. Monge; S. Passaggio; C. Patrignani; E. Robutti; A. Santroni; S. Tosi; K. S. Chaisanguanthum; M. Morii; J. Marks; S. Schenk; U. Uwer; V. Klose; H. M. Lacker; D. J. Bard; P. D. Dauncey; J. A. Nash; W. Panduro Vazquez; M. Tibbetts; P. K. Behera; X. Chai; M. J. Charles; U. Mallik; J. Cochran; H. B. Crawley; L. Dong; W. T. Meyer; S. Prell; E. I. Rosenberg; A. E. Rubin; Y. Y. Gao; A. V. Gritsan; Z. J. Guo; C. K. Lae; A. G. Denig; M. Fritsch; G. Schott; N. Arnaud; J. Béquilleux; A. D'Orazio; M. Davier; J. Firmino da Costa; G. Grosdidier; A. Höcker; V. Lepeltier; F. Le Diberder; A. M. Lutz; S. Pruvot; P. Roudeau; M. H. Schune; J. Serrano; V. Sordini; A. Stocchi; G. Wormser; D. J. Lange; D. M. Wright; I. Bingham; J. P. Burke; C. A. Chavez; J. R. Fry; E. Gabathuler; R. Gamet; D. E. Hutchcroft; D. J. Payne; C. Touramanis; A. J. Bevan; C. K. Clarke; K. A. George; F. di Lodovico; R. Sacco; M. Sigamani; G. Cowan; H. U. Flaecher; D. A. Hopkins; S. Paramesvaran; F. Salvatore; A. C. Wren; C. L. Davis; K. E. Alwyn; D. Bailey; R. J. Barlow; Y. M. Chia; C. L. Edgar; G. Jackson; G. D. Lafferty; T. J. West; J. I. Yi; J. Anderson; C. Chen; A. Jawahery; D. A. Roberts; G. Simi; J. M. Tuggle; C. Dallapiccola; X. Li; E. Salvati; S. Saremi; R. Cowan; D. Dujmic; P. H. Fisher; K. Koeneke; G. Sciolla; M. Spitznagel; F. Taylor; R. K. Yamamoto; M. Zhao; P. M. Patel; S. H. Robertson; A. Lazzaro; V. Lombardo; F. Palombo; J. M. Bauer; L. Cremaldi; V. Eschenburg; R. Godang; R. Kroeger; D. A. Sanders; D. J. Summers; H. W. Zhao; M. Simard; P. Taras; F. B. Viaud; H. Nicholson; G. de Nardo; L. Lista; D. Monorchio; G. Onorato; C. Sciacca; G. Raven; H. L. Snoek; C. P. Jessop; K. J. Knoepfel; J. M. Losecco; W. F. Wang; G. Benelli; L. A. Corwin; K. Honscheid; H. Kagan; R. Kass; J. P. Morris; A. M. Rahimi; J. J. Regensburger; S. J. Sekula; Q. K. Wong; N. L. Blount; J. Brau; R. Frey; O. Igonkina; J. A. Kolb; M. Lu; R. Rahmat; N. B. Sinev; D. Strom; J. Strube; E. Torrence; G. Castelli; N. Gagliardi; M. Margoni; M. Morandin; M. Posocco; M. Rotondo; F. Simonetto; R. Stroili; C. Voci; P. Del Amo Sanchez; E. Ben-Haim; H. Briand; G. Calderini; J. Chauveau; P. David; L. Del Buono; O. Hamon; Ph. Leruste; J. Ocariz; A. Perez; J. Prendki; S. Sitt; L. Gladney; M. Biasini; R. Covarelli; E. Manoni; C. Angelini; G. Batignani; S. Bettarini; M. Carpinelli; A. Cervelli; F. Forti; M. A. Giorgi; A. Lusiani; G. Marchiori; M. Morganti; N. Neri; E. Paoloni; G. Rizzo; J. J. Walsh; D. Lopes Pegna; C. Lu; J. Olsen; A. J. S. Smith; A. V. Telnov; F. Anulli; E. Baracchini; G. Cavoto; D. Del Re; E. di Marco; R. Faccini; F. Ferrarotto; F. Ferroni; M. Gaspero; P. D. Jackson; L. Li Gioi; M. A. Mazzoni; S. Morganti; G. Piredda; F. Polci; F. Renga; C. Voena; M. Ebert

2009-01-01

122

Energy deposition accompanying pion double charge exchange: Radiochemical study of the 209Bi(pi+, pi-xn)209xAt reactions  

Microsoft Academic Search

The pion double charge exchange reactions, 209Bi(pi+, pi-xn)209-xAt, have been studied by radiochemical techniques for incident pion energies of 100, 180, and 300 MeV. Cross sections for the chemically separated At isotopes A=205-209 were determined by alpha-particle and gamma-ray spectroscopy. The contribution of secondary processes, such as 209Bi(pi+, 3,4He)X followed by 209Bi(4He, xn)213-xAt and 209Bi(3He, xn)212-xAt, which mimic the double

J. L. Clark; P. E. Haustein; T. J. Ruth; J. Hudis; A. A. Caretto Jr.

1983-01-01

123

Computational characterization and modeling of buckyball tweezers: density functional study of concave convex pi...pi interactions  

Microsoft Academic Search

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. The geometries and binding energies of a recent buckyball tweezers (C60H28) and its supramolecular complexes are investigated using recently developed

Yan Zhao; Donald G. Truhlar

2008-01-01

124

B-DNA structure and stability: the role of hydrogen bonding, ?-? stacking interactions, twist-angle, and solvation.  

PubMed

We have computationally investigated the structure and stability of B-DNA. To this end, we have analyzed the bonding in a series of 47 stacks consisting of two base pairs, in which the base pairs cover the full range of natural Watson-Crick pairs, mismatched pairs, and artificial DNA base pairs. Our analyses provide detailed insight into the role and relative importance of the various types of interactions, such as, hydrogen bonding, ?-? stacking interactions, and solvation/desolvation. Furthermore, we have analyzed the functionality of the twist-angle on the stability of the structure. Interestingly, we can show that all stacked base pairs benefit from a stabilization by 6 to 12 kcal mol(-1) if stacked base pairs are twisted from 0° to 36°, that is, if they are mutually rotated from a congruent superposition to the mutually twisted stacking configuration that occurs in B-DNA. This holds especially for stacked AT pairs but also for other stacked base pairs, including GC. The electronic mechanism behind this preference for a twisted arrangement depends on the base pairs involved. We also show that so-called "diagonal interactions" (or cross terms) in the stacked base pairs are crucial for understanding the stability of B-DNA, in particular, in GC-rich sequences. PMID:24871817

Poater, Jordi; Swart, Marcel; Bickelhaupt, F Matthias; Fonseca Guerra, Célia

2014-06-11

125

Doubly interpenetrated hms-type metal organic framework formed by perfect face-to-face ?…? stacking interactions  

Microsoft Academic Search

The cooperative control of coordinate-covalent bonds, strong hydrogen bonds and perfect face-to-face ?…? stacking interactions leads to a new Cu(II) coordination polymer with unusual doubly interpenetrated (3,5)-connected hms topology.

Haixia Zhang; Fei Wang; Yao Kang; Jian Zhang

2010-01-01

126

Melt blending in situ enhances the interaction between polystyrene and graphene through ?-? stacking.  

PubMed

The effect of melt blending on the interaction between graphene and polystyrene (PS) matrix has been investigated in this paper. The interaction between graphene and PS was significantly enhanced by melt blending, which led to an increased amount of PS-functional graphene (PSFG) exhibiting good solubility in some solvents. The PS chains on PSFG could effectively prevent the graphene sheets from aggregating and the prepared PS/PSFG composites exhibited a homogeneous dispersion and an improved electrical property. The mechanism of melt blending on this enhanced interaction was attributed to the formation of ?-? stacking during the melt blending. Moreover, the formation of chemical bonding during melt blending may have also enhanced the interaction. PMID:21744831

Shen, Bin; Zhai, Wentao; Chen, Cao; Lu, Dingding; Wang, Jing; Zheng, Wenge

2011-08-01

127

Measurement of D^0-\\bar{D^0} Mixing From a Time-Dependent Amplitude Analysis of D^0\\ -> K^+\\pi^-\\pi0 Decays  

SciTech Connect

The authors present evidence of D{sup 0}-{bar D}{sup 0} mixing using a time-dependent amplitude analysis of the decay D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} in a data sample of 384 fb{sup -1} collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, they measure the mixing parameters x{prime}{sub K{pi}{pi}{sup 0}} = [2.61{sub -0.68}{sup +0.57}(stat.) {+-} 0.39(syst.)]%, y{prime}{sub K{pi}{pi}{sup 0}} = [-0.06{sub -0.64}{sup +0.55}(stat.) {+-} 0.34(syst.)]%. The confidence level for the data to be consistent with the no-mixing hypothesis is 0.1%, including systematic uncertainties. This result is inconsistent with the no-mixing hypothesis with a significance of 3.2 standard deviations. They find no evidence of CP violation in mixing.

Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, Antimo; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, Bjarne; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, Robert N.; Jacobsen, R.G.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Banca di Roma /Frascati /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2008-08-04

128

Measurements of branching fractions and CP-violating asymmetries in B0-->pi+pi-, K+pi-, K+K- decays.  

PubMed

We present measurements of branching fractions and CP-violating asymmetries for two-body neutral B meson decays to charged pions and kaons based on a sample of about 88x10(6) Upsilon(4S)-->BB decays. From a time-independent fit we measure the charge-averaged branching fractions B(B0-->pi+pi-)=(4.7+/-0.6+/-0.2)x10(-6), B(B0-->K+pi-)=(17.9+/-0.9+/-0.7)x10(-6), and the direct CP-violating charge asymmetry A(Kpi)=-0.102+/-0.050+/-0.016 [-0.188,-0.016], where the ranges in square brackets indicate the 90% confidence intervals. From a time-dependent fit we measure the B0-->pi+pi- CP-violating parameters S(pipi)=0.02+/-0.34+/-0.05 [-0.54,+0.58] and C(pipi)=-0.30+/-0.25+/-0.04 [-0.72,+0.12]. PMID:12513134

Aubert, B; Boutigny, D; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Harrison, T J; Hawkes, C M; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Peters, K; Schmuecker, H; Steinke, M; Barlow, N R; Bhimji, W; Boyd, J T; Chevalier, N; Clark, P J; Cottingham, W N; Mackay, C; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Jolly, S; McKemey, A K; Blinov, V E; Bukin, A D; Buzykaev, A R; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M; McMahon, S; Stoker, D P; Buchanan, C; Chun, S; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H; Prell, S; Rahatlou, Sh; Raven, G; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beringer, J; Eisner, A M; Grothe, M; Heusch, C A; Lockman, W S; Pulliam, T; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Bloom, P; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; T'Jampens, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Falbo, M; Borean, C; Bozzi, C; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Bartoldus, R; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Lacker, H M; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Trincaz-Duvoid, S; Wormser, G; Bionta, R M; Brigljevi?, V; Lange, D J; van Bibber, K; Wright, D M; Bevan, A J; Fry, J R; Gabathuler, E; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Morton, G W; Nash, J A; Sanders, P; Smith, D; Taylor, G P; Back, J J; Bellodi, G; Dixon, P; Harrison, P F; Potter, R J L; Shorthouse, H W; Strother, P; Vidal, P B; Cowan, G; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Jackson, F; Lafferty, G D; Lyon, A J; Savvas, N; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Lillard, V; Roberts, D A; Schieck, J R; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Staengle, H; Willocq, S; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Milek, M; Patel, P M; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Hast, C; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R G; Gabriel, T A; Brau, J; Frey, R; Iwasaki, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; Stark, J; Manfredi, P F; Re, V; Speziali, V; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Campagna, E; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A

2002-12-31

129

Applicability of the nearest-neighbor-interaction model for stacking-fault energies  

NASA Astrophysics Data System (ADS)

In a recent paper [N. M. Rosengaard and H. L. Skriver, Phys. Rev. B 47, 12 865 (1993)], it has been demonstrated by means of the linear-muffin-tin-orbital theory in the atomic-sphere approximation that the energies for the fcc stacking faults may be reasonably estimated in a nearest-neighbor-interaction model from the energy differences between the fcc and hcp phases. It is now shown by ab initio pseudopotential calculations that the model itself remains essentially valid when abandoning the atomic-sphere approximation, although the errors of the model are intensified and the quantitative results may be considerably influenced by this abandonment.

Schweizer, S.; Elsässer, C.; Fähnle, M.

1993-11-01

130

Molecular dynamics study of the interactions between dislocation and imperfect stacking fault tetrahedron in Cu  

NASA Astrophysics Data System (ADS)

The microstructure of irradiated face centered cubic alloys with low stacking fault energy is distinguished by the formation of a high number density of nanometer size stacking fault tetrahedra (SFT). A recent transmission electron microscopy investigation of high-energy proton irradiated copper [16] has shown that nearly 50% of the visible SFT population are not perfect SFTs, but rather consist of truncated SFT and/or groups of overlapping SFT. This paper presents the results of atomistic molecular dynamics simulations of the interaction between gliding dislocations, of either edge or screw character, and truncated SFT or overlapping SFT. The most common result of the edge dislocation interaction with a truncated SFT is defect shearing, ultimately leading to complete separation into two smaller defect clusters. Partial absorption of the truncated SFT is the most common result of the interaction with a screw dislocation, resulting in the formation of super-jog (or helical) segments as the defect is absorbed into the dislocation core. The resulting non-planar screw dislocation is self-pinned with reduced mobility and is re-emitted as a similar truncated SFT as the applied shear stress is increased. The re-emitted truncated SFT is often rotated and translated relative to the original position. These observations are consistent with the hypothesis that shearing (decreased defect cluster size) and dislocation dragging of the defect clusters by partial absorption into the dislocation core contributes to the formation of defect-free channels.

Saintoyant, Lucie; Lee, Hyon-Jee; Wirth, Brian D.

2007-04-01

131

Extracting drug-drug interaction from the biomedical literature using a stacked generalization-based approach.  

PubMed

Drug-drug interaction (DDI) detection is particularly important for patient safety. However, the amount of biomedical literature regarding drug interactions is increasing rapidly. Therefore, there is a need to develop an effective approach for the automatic extraction of DDI information from the biomedical literature. In this paper, we present a Stacked Generalization-based approach for automatic DDI extraction. The approach combines the feature-based, graph and tree kernels and, therefore, reduces the risk of missing important features. In addition, it introduces some domain knowledge based features (the keyword, semantic type, and DrugBank features) into the feature-based kernel, which contribute to the performance improvement. More specifically, the approach applies Stacked generalization to automatically learn the weights from the training data and assign them to three individual kernels to achieve a much better performance than each individual kernel. The experimental results show that our approach can achieve a better performance of 69.24% in F-score compared with other systems in the DDI Extraction 2011 challenge task. PMID:23785452

He, Linna; Yang, Zhihao; Zhao, Zhehuan; Lin, Hongfei; Li, Yanpeng

2013-01-01

132

Strain interactions and defect formation in stacked InGaAs quantum dot and dot-in-well structures  

Microsoft Academic Search

The growth of high-quality stacked quantum dot (QD) structures represents one of the key challenges for future device applications. Electronic coupling between QDs requires closely separated electronic levels and thin barrier layers, requiring near identical composition and shape, despite strong strain interactions. This paper presents a detailed characterization study of stacked InGaAs QD and InAs\\/InGaAs dot-in-well (DWELL) structures using cross-sectional

M. Gutiérrez; M. Hopkinson; H. Y. Liu; J. S. Ng; M. Herrera; D. González; R. Garcia; R. Beanland

2005-01-01

133

First model-independent determination of the relative strong phase between D0 and Dmacr 0-->KS0pi+pi- and its impact on the CKM angle gamma\\/varphi3 measurement  

Microsoft Academic Search

We exploit the quantum coherence between pair-produced D0 and Dmacr 0 in psi(3770) decays to make a first determination of the relative strong phase differences between D0-->KS0pi+pi- and Dmacr 0-->KS0pi+pi-, which are of great importance in determining the Cabibbo-Kobayashi-Maskawa angle gamma\\/varphi3 in B--->D0( Dmacr 0)K- decays. Using 818pb-1 of e+e- collision data collected with the CLEO-c detector at Ecm=3.77GeV, we

R. A. Briere; H. Vogel; P. U. E. Onyisi; J. L. Rosner; J. P. Alexander; D. G. Cassel; J. E. Duboscq; R. Ehrlich; L. Fields; L. Gibbons; R. Gray; S. W. Gray; D. L. Hartill; B. K. Heltsley; D. Hertz; J. M. Hunt; J. Kandaswamy; D. L. Kreinick; V. E. Kuznetsov; J. Ledoux; H. Mahlke-Krüger; D. Mohapatra; J. R. Patterson; D. Peterson; D. Riley; A. Ryd; A. J. Sadoff; X. Shi; S. Stroiney; W. M. Sun; T. Wilksen; S. B. Athar; J. Yelton; P. Rubin; S. Mehrabyan; N. Lowrey; M. Selen; E. J. White; J. Wiss; R. E. Mitchell; M. R. Shepherd; D. Besson; T. K. Pedlar; D. Cronin-Hennessy; K. Y. Gao; J. Hietala; Y. Kubota; T. Klein; R. Poling; A. W. Scott; P. Zweber; S. Dobbs; Z. Metreveli; K. K. Seth; B. J. Y. Tan; A. Tomaradze; J. Libby; L. Martin; A. Powell; G. Wilkinson; H. Mendez; J. Y. Ge; D. H. Miller; V. Pavlunin; B. Sanghi; I. P. J. Shipsey; B. Xin; G. S. Adams; D. Hu; B. Moziak; J. Napolitano; K. M. Ecklund; Q. He; J. Insler; H. Muramatsu; C. S. Park; E. H. Thorndike; F. Yang; M. Artuso; S. Blusk; N. Horwitz; S. Khalil; J. Li; K. Randrianarivony; N. Sultana; T. Skwarnicki; S. Stone; J. C. Wang; L. M. Zhang; G. Bonvicini; D. Cinabro; M. Dubrovin; A. Lincoln; P. Zhou; J. Zhu; P. Naik; J. Rademacker; D. M. Asner; K. W. Edwards; J. Reed; A. N. Robichaud; G. Tatishvili

2009-01-01

134

Dislocation?stacking fault tetrahedron interaction: what can we learn from atomic-scale modelling*1  

NASA Astrophysics Data System (ADS)

The high number density of stacking fault tetrahedra (SFTs) observed in irradiated fcc metals suggests that they should contribute to radiation-induced hardening and, therefore, taken into account when estimating mechanical properties changes of irradiated materials. The central issue is describing the individual interaction between a moving dislocation and an SFT, which is characterized by a very fine size scale, ˜100 nm. This scale is amenable to both in situ TEM experiments and large-scale atomic modelling. In this paper we present results of an atomistic simulation of dislocation-SFT interactions using molecular dynamics (MD). The results are compared with observations from in situ deformation experiments. It is demonstrated that in some cases the simulations and experimental observations are quite similar, suggesting a reasonable interpretation of experimental observations.

Osetsky, Yu. N.; Stoller, R. E.; Matsukawa, Y.

2004-08-01

135

Dislocation-stacking fault tetrahedron interaction: what can we learn from atomic scale modelling.  

SciTech Connect

The high number density of stacking fault tetrahedra (SFTs) observed in irradiated fcc metals suggests that they should contribute to radiation-induced hardening and, therefore, taken into account when estimating mechanical properties changes of irradiated materials. The central issue is describing the individual interaction between a moving dislocation and an SFT, which is characterized by a very fine size scale, {approx}100 nm. This scale is amenable to both in situ TEM experiments and large-scale atomic modelling. In this paper we present results of an atomistic simulation of dislocation-SFT interactions using molecular dynamics (MD). The results are compared with observations from in situ deformation experiments. It is demonstrated that in some cases the simulations and experimental observations are quite similar, suggesting a reasonable interpretation of experimental observations.

Osetskiy, Yury N [ORNL; Stoller, Roger E [ORNL; Matsukawa, Yoshitaka [ORNL

2004-01-01

136

Evidence of ?-stacking Interactions in the Self-Assembly of hIAPP22–29†  

PubMed Central

The role aromatic amino acids play in the formation of amyloid is a subject of controversy. In an effort to clarify the contribution of aromaticity to the self-assembly of hIAPP22–29, peptide analogs containing electron donating groups (EDGs) or electron withdrawing groups (EWGs) as substituents on the aromatic ring of Phe-23 at the para position have been synthesized and characterized using turbidity measurements in conjunction with Raman, and fluorescence spectroscopy. Results indicate the incorporation of EDGs on the aromatic ring of Phe-23 virtually abolish the ability of hIAPP22–29 to form amyloid. Peptides containing EWGs were still capable of forming aggregates. These aggregates were found to be rich in ?-sheet secondary structure. TEM images of the aggregates confirm the presence of amyloid fibrils. The observed difference in amyloidogenic propensity between peptides containing EDGs and those with EWGs appears not to be based on differences in peptide hydrophobicity. Fluorescence and Raman spectroscopic investigations reveal that the environment surrounding the aromatic ring becomes more hydrophobic and ordered upon aggregation. Furthermore, Raman measurements of peptide analogs containing EWGs, conclusively demonstrate a distinct downshift in the -C=C- ring mode (ca. 1600 cm?1) upon aggregation that has previously been shown to be indicative of ?-stacking. While previous work has demonstrated that ?-stacking is not an absolute requirement for fibrillization, our findings indicate that Phe-23 also contributes to fibril formation through ?-stacking interactions and that it is not only the hydrophobic nature of this residue that is relevant in the self-assembly of hIAPP22–29.

Profit, Adam A.; Felsen, Valentina; Chinwong, Justina; Mojica, Elmer-Rico E.; Desamero, Ruel Z. B.

2012-01-01

137

Limits on D0-macro D0 mixing and CP violation from the ratio of lifetimes for decay to K-pi+, K-K+, and pi- pi+.  

PubMed

We present a measurement of D0-macro D0 mixing parameters using the ratios of lifetimes extracted from samples of D0 mesons decaying to K-pi(+), K-K+, and pi(-)pi(+). Using 91 fb(-1) of data collected by the BABAR detector at the PEP-II asymmetric-energy B Factory, we obtain a value Y=[0.8+/-0.4(stat.)(+0.5)(-0.4)(syst.)]%, which, in the limit of CP conservation, corresponds to the mixing parameter y=Delta Gamma/2 Gamma. Using the difference in lifetimes of D0 and macro D0 mesons, we obtain the CP-violation parameter Delta Y=[-0.8+/-0.6(stat.)+/-0.2(syst.)]%. PMID:14525353

Aubert, B; Barate, R; Boutigny, D; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; Kukartsev, G; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Knowles, D J; Morgan, S E; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmuecker, H; Steinke, M; Barlow, N R; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Mackay, C; Wilson, F F; Abe, K; Cuhadar-Donszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M; McMahon, S; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Beringer, J; Eisner, A M; Grothe, M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Barillari, T; Blanc, F; Bloom, P; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Aspinwall, M L; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Morton, G W; Nash, J A; Sanders, P; Taylor, G P; Grenier, G J; Lee, S-J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Brigljevi?, V; Cheng, C H; Lange, D J; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, E; Gamet, R; Kay, M; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Shorthouse, H W; Strother, P; Vidal, P B; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Hart, P A; Jackson, F; Lafferty, G D; Lyon, A J; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Milek, M; Patel, P M; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Hast, C; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; LoSecco, J M; Gabriel, T A; Brau, B; Pulliam, T; Brau, J; Frey, R; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; John, M J J; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; Stark, J; T'Jampens, S; Manfredi, P F; Re, V

2003-09-19

138

Precise measurement of the e+e- --> pi+pi-(gamma) cross section with the initial state radiation method at BABAR.  

PubMed

A precise measurement of the cross section of the process e(+)e(-) --> pi(+)pi(-)(gamma) from threshold to an energy of 3 GeV is obtained with the initial state radiation (ISR) method using 232 fb(-1) of data collected with the BABAR detector at e(+)e(-) center-of-mass energies near 10.6 GeV. The ISR luminosity is determined from a study of the leptonic process e(+)e(-) --> mu(+)mu(-)gamma(gamma). The leading-order hadronic contribution to the muon magnetic anomaly calculated using the pipi cross section measured from threshold to 1.8 GeV is (514.1 +/- 2.2(stat) +/- 3.1(syst)) x 10(-10). PMID:20366141

Aubert, B; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Martinelli, M; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Hooberman, B; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Ongmongkolkul, P; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Feltresi, E; Hauke, A; Jasper, H; Karbach, T M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Bernard, D; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Fioravanti, E; Franchini, P; Luppi, E; Munerato, M; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Lacker, H M; Lueck, T; Volk, A; Dauncey, P D; Tibbetts, M; Behera, P K; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; D'Orazio, A; Davier, M; Derkach, D; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Malaescu, B; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, L L; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Fritsch, M; Gradl, W; Hafner, A; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Palombo, F; Stracka, S; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Zhao, H W; Nguyen, X; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Sekula, S J; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; del Amo Sanchez, P; Ben-Haim, E; Bonneaud, G R; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Allen, M T; Aston, D; Bard, D J; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Fulsom, B G; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B

2009-12-01

139

Measurement of D{0}-D[-over]{0} mixing from a time-dependent amplitude analysis of D{0}-->K+pi{-}pi{0} decays.  

PubMed

We present evidence of D{0}-D[-over ]{0} mixing using a time-dependent amplitude analysis of the decay D{0}-->K+pi{-}pi;{0} in a data sample of 384 fb{-1} collected with the BABAR detector at the PEP-II e+e{-} collider at the Stanford Linear Accelerator Center. Assuming CP conservation, we measure the mixing parameters x{Kpipi{0}}{'}=[2.61{-0.68}{+0.57}(stat)+/-0.39(syst)]%, y{Kpipi;{0}}{'}=[-0.06{-0.64}{+0.55}(stat)+/-0.34(syst)]%. This result is inconsistent with the no-mixing hypothesis with a significance of 3.2 standard deviations. We find no evidence of CP violation in mixing. PMID:20366027

Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Tico, J Garra; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Cahn, R N; Jacobsen, R G; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Wilson, M G; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Ulmer, K A; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Mader, W F; Nogowski, R; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Marks, J; Schenk, S; Uwer, U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Nash, J A; Vazquez, W Panduro; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; da Costa, J Firmino; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; George, K A; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Alwyn, K E; Bailey, D; Barlow, R J; Chia, Y M; Edgar, C L; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Li, X; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Sanchez, P del Amo; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Pegna, D Lopes; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Escalier, M; Esteve, L; Ganzhur, S F

2009-11-20

140

Measurements of Branching Fractions and CP-Violating Asymmetries in B0-->pi+pi-, K+pi-, K+K- Decays  

Microsoft Academic Search

We present measurements of branching fractions and CP-violating asymmetries for two-body neutral B¯ meson decays to charged pions and kaons based on a sample of about 88×106 Upsilon(4S)-->BB¯ decays. From a time-independent fit we measure the charge-averaged branching fractions B(B0-->pi+pi- )=(4.7±0.6±0.2)×10-6, B(B0-->K+pi- )=(17.9±0.9±0.7)×10-6, and the direct CP-violating charge asymmetry AKpi=-0.102±0.050±0.016 [-0.188,-0.016], where the ranges in square brackets indicate the 90%

B. Aubert; D. Boutigny; J.-M. Gaillard; A. Hicheur; Y. Karyotakis; J. P. Lees; P. Robbe; V. Tisserand; A. Zghiche; A. Palano; A. Pompili; J. C. Chen; N. D. Qi; G. Rong; P. Wang; Y. S. Zhu; G. Eigen; I. Ofte; B. Stugu; G. S. Abrams; A. W. Borgland; A. B. Breon; D. N. Brown; J. Button-Shafer; R. N. Cahn; E. Charles; M. S. Gill; A. V. Gritsan; Y. Groysman; R. G. Jacobsen; R. W. Kadel; J. Kadyk; L. T. Kerth; Yu. G. Kolomensky; J. F. Kral; C. Leclerc; M. E. Levi; G. Lynch; L. M. Mir; P. J. Oddone; T. J. Orimoto; M. Pripstein; N. A. Roe; A. Romosan; M. T. Ronan; V. G. Shelkov; A. V. Telnov; W. A. Wenzel; T. J. Harrison; C. M. Hawkes; D. J. Knowles; S. W. O'Neale; R. C. Penny; A. T. Watson; N. K. Watson; T. Deppermann; K. Goetzen; H. Koch; B. Lewandowski; K. Peters; H. Schmuecker; M. Steinke; N. R. Barlow; W. Bhimji; J. T. Boyd; N. Chevalier; P. J. Clark; W. N. Cottingham; C. Mackay; F. F. Wilson; K. Abe; C. Hearty; T. S. Mattison; J. A. McKenna; D. Thiessen; S. Jolly; A. K. McKemey; V. E. Blinov; A. D. Bukin; A. R. Buzykaev; V. B. Golubev; V. N. Ivanchenko; A. A. Korol; E. A. Kravchenko; A. P. Onuchin; S. I. Serednyakov; Yu. I. Skovpen; A. N. Yushkov; D. Best; M. Chao; D. Kirkby; A. J. Lankford; M. Mandelkern; S. McMahon; D. P. Stoker; C. Buchanan; S. Chun; H. K. Hadavand; E. J. Hill; D. B. Macfarlane; H. Paar; S. Prell; Sh. Rahatlou; G. Raven; U. Schwanke; V. Sharma; J. W. Berryhill; C. Campagnari; B. Dahmes; P. A. Hart; N. Kuznetsova; S. L. Levy; O. Long; A. Lu; M. A. Mazur; J. D. Richman; W. Verkerke; J. Beringer; A. M. Eisner; M. Grothe; C. A. Heusch; W. S. Lockman; T. Pulliam; T. Schalk; R. E. Schmitz; B. A. Schumm; A. Seiden; M. Turri; W. Walkowiak; D. C. Williams; M. G. Wilson; E. Chen; G. P. Dubois-Felsmann; A. Dvoretskii; D. G. Hitlin; F. C. Porter; A. Ryd; A. Samuel; S. Yang; S. Jayatilleke; G. Mancinelli; B. T. Meadows; M. D. Sokoloff; T. Barillari; P. Bloom; W. T. Ford; U. Nauenberg; A. Olivas; P. Rankin; J. Roy; J. G. Smith; W. C. van Hoek; L. Zhang; J. L. Harton; T. Hu; M. Krishnamurthy; A. Soffer; W. H. Toki; R. J. Wilson; J. Zhang; D. Altenburg; T. Brandt; J. Brose; T. Colberg; M. Dickopp; R. S. Dubitzky; A. Hauke; E. Maly; R. Müller-Pfefferkorn; S. Otto; K. R. Schubert; R. Schwierz; B. Spaan; L. Wilden; D. Bernard; G. R. Bonneaud; F. Brochard; J. Cohen-Tanugi; S. Ferrag; S. T'jampens; Ch. Thiebaux; G. Vasileiadis; M. Verderi; A. Anjomshoaa; R. Bernet; A. Khan; D. Lavin; F. Muheim; S. Playfer; J. E. Swain; J. Tinslay; M. Falbo; C. Borean; C. Bozzi; L. Piemontese; A. Sarti; E. Treadwell; F. Anulli; R. Baldini-Ferroli; A. Calcaterra; R. de Sangro; D. Falciai; G. Finocchiaro; P. Patteri; I. M. Peruzzi; M. Piccolo; A. Zallo; S. Bagnasco; A. Buzzo; R. Contri; G. Crosetti; M. Lo Vetere; M. Macri; M. R. Monge; S. Passaggio; F. C. Pastore; C. Patrignani; E. Robutti; A. Santroni; S. Tosi; S. Bailey; M. Morii; R. Bartoldus; G. J. Grenier; U. Mallik; J. Cochran; H. B. Crawley; J. Lamsa; W. T. Meyer; E. I. Rosenberg; J. Yi; M. Davier; G. Grosdidier; A. Höcker; H. M. Lacker; S. Laplace; F. Le Diberder; V. Lepeltier; A. M. Lutz; T. C. Petersen; S. Plaszczynski; M. H. Schune; L. Tantot; S. Trincaz-Duvoid; G. Wormser; R. M. Bionta; V. Brigljevic; D. J. Lange; K. van Bibber; D. M. Wright; A. J. Bevan; J. R. Fry; E. Gabathuler; R. Gamet; M. George; M. Kay; D. J. Payne; R. J. Sloane; C. Touramanis; M. L. Aspinwall; D. A. Bowerman; P. D. Dauncey; U. Egede; I. Eschrich; G. W. Morton; J. A. Nash; P. Sanders; D. Smith; G. P. Taylor; J. J. Back; G. Bellodi; P. Dixon; P. F. Harrison; R. J. Potter; H. W. Shorthouse; P. Strother; P. B. Vidal; G. Cowan; H. U. Flaecher; S. George; M. G. Green; A. Kurup; C. E. Marker; T. R. McMahon; S. Ricciardi; F. Salvatore; G. Vaitsas; M. A. Winter; C. L. Davis; J. Allison; R. J. Barlow; A. C. Forti; F. Jackson; G. D. Lafferty; A. J. Lyon; N. Savvas; J. H. Weatherall; J. C. Williams; A. Farbin; A. Jawahery; V. Lillard; D. A. Roberts; J. R. Schieck; G. Blaylock; C. Dallapiccola; K. T. Flood; S. S. Hertzbach; R. Kofler; V. B. Koptchev; T. B. Moore; H. Staengle; S. Willocq; B. Brau; R. Cowan; G. Sciolla; F. Taylor; R. K. Yamamoto; M. Milek; P. M. Patel; F. Palombo; J. M. Bauer; L. Cremaldi; V. Eschenburg; R. Kroeger; J. Reidy; D. A. Sanders; D. J. Summers; C. Hast; P. Taras; H. Nicholson; C. Cartaro; N. Cavallo; G. de Nardo; F. Fabozzi; C. Gatto; L. Lista; P. Paolucci; D. Piccolo; C. Sciacca; J. M. Losecco; J. R. Alsmiller; T. A. Gabriel; J. Brau; R. Frey; M. Iwasaki; C. T. Potter; N. B. Sinev; D. Strom; E. Torrence; F. Colecchia; A. Dorigo; F. Galeazzi; M. Margoni; M. Morandin; M. Posocco; M. Rotondo; F. Simonetto; R. Stroili; C. Voci; M. Benayoun; H. Briand; J. Chauveau; P. David; Ch. de La Vaissière; L. del Buono; O. Hamon; Ph. Leruste; J. Ocariz; M. Pivk; L. Roos; J. Stark; P. F. Manfredi; V. Re; V. Speziali; L. Gladney; Q. H. Guo

2002-01-01

141

Doping Dependence of the $(\\pi,\\pi)$ Shadow Band in La-Based Cuprates Studied by Angle-Resolved Photoemission Spectroscopy  

SciTech Connect

The ({pi},{pi}) shadow band (SB) in La-based cuprate family (La214) was studied by angle-resolved photoemission spectroscopy (ARPES) over a wide doping range from x = 0.01 to x = 0.25. Unlike the well-studied case of the Bi-based cuprate family, an overall strong, monotonic doping dependence of the SB intensity at the Fermi level (E{sub F}) was observed. In contrast to a previous report for the presence of the SB only close to x = 1/8, we found it exists in a wide doping range, associated with a doping-independent ({pi},{pi}) wave vector but strongly doping-dependent intensity: It is the strongest at x {approx} 0.03 and systematically diminishes as the doping increases until it becomes negligible in the overdoped regime. This SB with the observed doping dependence of intensity can in principle be caused by the antiferromagnetic fluctuations or a particular form of low-temperature orthorhombic lattice distortion known to persist up to x {approx} 0.21 in the system, with both being weakened with increasing doping. However, a detailed binding energy dependent analysis of the SB at x = 0.07 does not appear to support the former interpretation, leaving the latter as a more plausible candidate, despite a challenge in quantitatively linking the doping dependences of the SB intensity and the magnitude of the lattice distortion. Our finding highlights the necessity of a careful and global consideration of the inherent structural complications for correctly understanding the cuprate Fermiology and its microscopic implication.

Shen, Z. X.

2011-08-15

142

Dinuclear platinum complexes containing planar aromatic ligands to enhance stacking interactions with proteins.  

PubMed

In an approach to design drugs with higher affinity for ?-? stacking and electrostatic interactions with targeted biomolecules, complexes of the type [{cis-Pt(A)2 (L)}2 -?-{trans-1,4-dach}](NO3 )4 ((A)2 =(NH3 )2 or ethylenediamine (en), L=quinoline (quin) or benzothiazole (bztz), dach=trans-1,4-diaminocyclohexane) were synthesized. The quinoline complex, [{cis-Pt(en)(quin)}2 -?-(dach)](NO3 )4 (9) was synthesized from the precursor K[PtCl3 (quin)] (1), while the benzothiazole complexes, [{cis-Pt(A)2 (bztz)}2 -?-(dach)](NO3 )4 ((A)2 =(NH3 )2 (10) and (A)2 =en (11)) were synthesized from the precursors cis-[Pt(A)2 Cl(bztz)] ((A)2 =(NH3 )2 (7) and (A)2 =en (8)). Their interactions with N-acetyltryptophan and a model pentapeptide (N-Ac-WLDSW-OH), modeled on the pentapeptide recognition sequence (FSDLW) of p53-mdm2 interaction, were examined by fluorescence spectroscopy. The dinuclear complexes were found to be significantly stronger at quenching the fluorescence of tryptophan than their mononuclear Pt-based analogues indicating stronger binding. Molecular modeling suggests a "sandwich" mode of binding, and the flexibility of the dinuclear motif can allow the design of more selective and stronger-binding complexes. Based on these results a further prototype, [{Pt(en)(9-EtGua)}2 ?-H2 N(CH2 )6 NH2 ](4+) , incorporating the purine 9-ethylguanine (9-EtG) as a stacking moiety, was prepared which showed good cytotoxicity in A2780 and OsACL tumor cell lines. PMID:24801050

Ma, Erin S F; Daniel, A Gerard; Farrell, Nicholas P

2014-06-01

143

The relevance of nonlinear stacking interactions in simple models of double-stranded DNA  

PubMed Central

Single molecule DNA experiments provide interesting data that allow a better understanding of the mechanical interactions between the strands and the nucleotides of this molecule. In some sense, these experiments complement the classical ones about DNA thermal denaturation. It is well known that the original Peyrard–Bishop (PB) model by means of a harmonic stacking potential and a nonlinear substrate potential has been able to predict the existence of a critical temperature of full denaturation of the molecule. In the present paper, driven by the findings of single molecule experiments, we substitute the original harmonic intra-strand stacking potential with a Duffing type potential. By elementary and analytical arguments, we show that with this choice it is possible to obtain a sharp transition in the classical domain wall solution of the PB model and the compactification of the classical solitary wave solutions of other models for the dynamics of DNA. We discuss why these solutions may improve our knowledge of the DNA dynamics in several directions.

Saccomandi, Giuseppe; Sgura, Ivonne

2006-01-01

144

Anions derived from squaric acid form interionic pi-stack and layered, hydrogen-bonded superstructures with organometallic sandwich cations: the magnetic behaviour of crystalline  

PubMed

Depending on the stoichiometric ratio, squaric acid (3,4-dihydroxy-3-cyclobutene-1,2-dione, H2SQA) reacts with [(eta6-C6H6)2Cr] in THF to form the crystalline material [(eta6-C6H6)2Cr][HSQA] (1) and in water to yield [[(eta6-C6H6)2Cr]2][SQA] x 6H2O (3); it also reacts with [(eta5-C5H5)2Co][OH] in water to form [[(eta5-C5H5)2Co]2][SQA] x 6H2O (4). Compound 1 is almost isostructural with the previously reported salt [(eta5-C5H5)2Co][HSQA] (2); its structure is based on pi-pi stacks between the benzene ligands and the hydrogen squarate anionic chains (pi-pi distance 3.375 A). Compounds 3 and 4 are isomorphous and have a structure in which layers of organometallic cations intercalate with layers of water molecules hydrogen bonded to squarate dianions. All crystals contain charge-assisted C-Hdelta+...Odelta- hydrogen bonds between the organometallic and the organic components, while negative O-H(-)...O(-) and O-H...O(2-) interactions are present in the pairs 1/3 and 2/4, respectively. In constrast to most organic salts of [(eta6-C6H6)2Cr]+ and [(eta5-C5H5)2Co]+ which are yellow, crystals of compounds 1-4 are orange. Reflectance spectra measured on the crystalline material 1 show the presence of an intense tail that can be assigned to a charge-transfer transition through the [(eta6-C6H6)2Cr]+/[HSQA]- pi-stacking interactions, while the pi stacking in 2 causes only a broadening of the band. The magnetic behaviour of 1 and 3 has been investigated by SQUID magnetometry. Both compounds are characterised by a weak antiferromagnetic interaction between the S=1/2 Cr centres of the [(eta6-C6H6)2Cr]+ cations, which is significantly stronger in 1 due to the pi-stacking with the HSQA- anions. PMID:10840952

Braga; Maini; Prodi; Caneschi; Sessoli; Grepioni

2000-04-14

145

Atomic-Scale Study of Dislocation-Stacking Fault Tetrahedron Interactions. Part I: Mechanisms.  

SciTech Connect

Stacking fault tetrahedra (SFTs) are formed under irradiation in fcc metals and alloys. The high number density of SFTs observed suggests that they should contribute to radiation-induced hardening and, therefore, be taken into account when estimating mechanical property changes of irradiated materials. The key issue in this is to describe the interaction between a moving dislocation and an individual SFT, which is distinguished by a small physical size of the order of {approx}1-10 nm. We have performed atomistic simulations of edge and screw dislocations interacting with SFTs of different sizes at different temperatures and strain rates. Five possible interaction outcomes have been identified, involving either partial absorption, or shearing or restoration of SFTs. The mechanisms that give rise to these processes are described and their dependence on interaction parameters, such as SFT size, dislocation-SFT geometry, temperature and stress/strain rate are determined. Mechanisms that help to explain the formation of defect-free channels cleared by gliding dislocations, as observed experimentally, are also discussed. Hardening due to the various mechanisms and their dependence on loading conditions will be presented in a following paper (Part II).

Osetskiy, Yury N [ORNL; Rodney, David [Genie Physique et Mecanique des Materiaux; Bacon, David J [University of Liverpool

2006-01-01

146

Experimental Study of the Reaction pi exp - p Implies pi exp 0 pi exp 0 N at 2.01 GeV/C. Its Use in a Simultaneous Phase Shift Analysis of the pi pi Channels.  

National Technical Information Service (NTIS)

We report results on pi exp + pi exp - implies pi exp 0 pi exp 0 total and differential cross sections from threshold to 1.1 GeV pi pi mass. These results have been obtained from a high-statistics experiment studying the reaction pi exp - p implies pi exp...

M. David

1979-01-01

147

Computational study of a screw dislocation interacting with a stacking-fault tetrahedron  

NASA Astrophysics Data System (ADS)

A numerical simulation study of the intersection process of a moving ½[110] screw dislocation with a perfect stacking-fault tetrahedron (SFT) in an fcc nickel crystal is carried out using molecular dynamics for different many-body potentials. When the glide plane of the screw dislocation coincides with one of the planes of the SFT, the interaction involves several dislocation reactions, jog line formation and bending of dislocation segments. The complex atomic processes are illustrated in detail and are shown to depend on the relative orientation of the defect and moving dislocation. In most cases, the jogs disappear quickly, but in special cases the jog lines in the dissociated dislocation remain even after the interaction process with the SFT, dragging some vacancies away. While in this geometrical set-up the main effect of the intersection is the ledge formation on the SFT, when the moving dislocation intersects the SFT in the middle part, it leads to slip and the separation of the SFT into two parts. Finally, if the screw dislocation passes at non-zero distance from the SFT the elastic interaction does not lead to any deformation of the SFT.

Szelestey, Peter; Patriarca, Marco; Kaski, Kimmo

2005-06-01

148

Potential of long chain ionic liquids for on-line sample concentration techniques: application to micelle to solvent stacking.  

PubMed

The performance of micelle to solvent stacking (MSS) in capillary zone electrophoresis (CZE) was improved for anionic analytes using the long chain ionic liquid type cationic surfactant 1-dodecyl-3-methylimidazolium tetrafluoroborate (C??-MIM-BF?). The peak heights and corrected peak areas of the test profens and herbicides were enhanced up to 59 and 110-fold, respectively when compared to typical injection. These were up to 10 times better compared to the surfactant cetyltrimethyl ammonium bromide as MSS carrier. This performance was attributed to the properties of C??-MIM-BF?. MSS requires micelles in the sample for transport of bound analytes to a stacking boundary that contains an organic solvent for effective electrophoretic mobility reversal. The ionic liquid micelles provided better analyte transport properties that resulted from its hydrophobic and pi-pi interaction capabilities. The good solubility of the ionic liquid in high percentages of organic solvent also facilitated a more effective reversal of mobility. The LODs obtained for the test analytes were from 0.06 to 0.12 ?g/mL. The linearity R² values in terms of peak height and corrected area were ? 0.99. The interday repeatabilities (%RSD, n=10,) were 0.5-2.2% for retention time, 1.9-4.7% for corrected areas and 4.1-6.4% for peak heights. PMID:21763663

Quirino, Joselito P; Anres, Philippe; Sirieix-Plénet, Juliette; Delaunay, Nathalie; Gareil, Pierre

2011-08-19

149

?-Stacking, C-H/?, and halogen bonding interactions in bromobenzene and mixed bromobenzene-benzene clusters.  

PubMed

Noncovalent interactions play an important role in many chemical and biochemical processes. Building upon our recent study of the homoclusters of chlorobenzene, where ?-? stacking and CH/? interactions were identified as the most important binding motifs, in this work we present a study of bromobenzene (PhBr) and mixed bromobenzene-benzene clusters. Electronic spectra in the region of the PhBr monomer S0-S1 (??*) transition were obtained using resonant two-photon ionization (R2PI) methods combined with time-of-flight mass analysis. As previously found for related systems, the PhBr cluster spectra show a broad feature whose center is red-shifted from the monomer absorption, and electronic structure calculations indicate the presence of multiple isomers and Franck-Condon activity in low-frequency intermolecular modes. Calculations at the M06-2X/aug-cc-pVDZ level find in total eight minimum energy structures for the PhBr dimer: four ?-stacked structures differing in the relative orientation of the Br atoms (denoted D1-D4), one T-shaped structure (D5), and three halogen bonded structures (D6-D8). The calculated binding energies of these complexes, corrected for basis set superposition error (BSSE) and zero-point energy (ZPE), are in the range of -6 to -24 kJ/mol. Time-dependent density functional theory (TDDFT) calculations predict that these isomers absorb over a range that is roughly consistent with the breadth of the experimental spectrum. To examine the influence of dipole-dipole interaction, R2PI spectra were also obtained for the mixed PhBr···benzene dimer, where the spectral congestion is reduced and clear vibrational structure is observed. This structure is well-simulated by Franck-Condon calculations that incorporate the lowest frequency intermolecular modes. Calculations find four minimum energy structures for the mixed dimer and predict that the binding energy of the global minimum is reduced by ~30% relative to the global minimum PhBr dimer structure. PMID:23978255

Reid, Scott A; Nyambo, Silver; Muzangwa, Lloyd; Uhler, Brandon

2013-12-19

150

NONWATER QUALITY IMPACTS OF CLOSED-CYCLE COOLING SYSTEMS AND THE INTERACTION OF STACK GAS AND COOLING TOWER PLUMES  

EPA Science Inventory

The report gives results of a literature survey of the nonwater quality impacts of closed-cycle cooling systems. Following discussions of cooling tower and stack gas plumes, interactions of these plumes are considered. For cooling tower plumes, plume types, behavior, salt drift g...

151

Equatorial ?-stacking interactions in diruthenium (II,III) tetracarboxylate complexes containing extended ?-systems  

NASA Astrophysics Data System (ADS)

The synthesis of three new valent-averaged tetracarboxylatodiruthenium (II,III) complexes, [Ru2(1-naphthylacetate)4(H2O)2](PF6)?4THF, 1?4THF, [Ru2(2-naphthoate)4(THF)2](PF6)?3THF, 2?3THF, and [Ru2(coumarin-3-carboxylate)4(MeOH)2](PF6)?MeOH?H2O, 3?MeOH?H2O, was accomplished using a well documented carboxylate exchange reaction. All three complexes were thoroughly characterized using infrared and UV-Vis spectroscopies, elemental analysis and X-ray diffraction. Due to the extended ?-systems present, two of the complexes, 2?3THF and 3?MeOH?H2O, display extensive ?-stacking in two dimensions, with similar interactions notably absent in 1?4THF due to the perpendicular orientation of the naphthyl rings. Modest H-bonding is seen in complexes 1?4THF and 3?MeOH?H2O. As these types of complexes are noted secondary building units (SBU's) in the construction of metal-organic frameworks (MOF's), the significance of these interactions in stabilizing even larger, supramolecular structures, are noted.

O'Rourke, Natasha F.; Ronaldson, Michael; Stanley Cameron, T.; Wang, Ruiyao; Aquino, Manuel A. S.

2013-11-01

152

Molecular dynamics study of the interactions between dislocation and imperfect stacking fault tetrahedron in Cu  

Microsoft Academic Search

The microstructure of irradiated face centered cubic alloys with low stacking fault energy is distinguished by the formation of a high number density of nanometer size stacking fault tetrahedra (SFT). A recent transmission electron microscopy investigation of high-energy proton irradiated copper [16] has shown that nearly 50% of the visible SFT population are not perfect SFTs, but rather consist of

Lucie Saintoyant; Hyon-Jee Lee; Brian D. Wirth

2007-01-01

153

Measurement of the Cabibbo-Kobayashi-Maskawa angle gamma in B+/--->D*K+/- decays with a Dalitz analysis of D-->K0(S)pi-pi+.  

PubMed

We report on a measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase gamma through a Dalitz analysis of neutral D decays to K0(S)pi-pi+ in the processes B+/- -->D*K+/-, D*-->Dpi0, Dgamma. Using a sample of 227 x 10(6) BB pairs collected by the BABAR detector, we measure the amplitude ratios r(B)=0.12+/-0.03+/-0.04 and r*(B)=0.17+/-0.10+/-0.03+/-0.03, the relative strong phases delta(B)=(104+/-45(+17+16)(-21-24))degrees and delta*(B)=(-64+/-41(+14)(-12)+/-15) degrees between the amplitudes A(B- -->D*0K-) and A(B- -->D*0)K-), and gamma=(70+/-31(+12+14)(-10-11))degrees. The first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the Dalitz model uncertainty. The results for the strong and weak phases have a twofold ambiguity. PMID:16197065

Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Pappagallo, M; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Kelly, M P; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bondioli, M; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Del Re, D; Hadavand, H K; Hill, E J; Macfarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Andreassen, R; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Klose, V; Lacker, H M; Maly, E; Nogowski, R; Otto, S; Petzold, A; Schott, G; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Schenk, S; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Mohapatra, A K; Cochran, J; Crawley, H B; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Petersen, T C; Pierini, M; Plaszczynski, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Li, X; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Kim, H; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Viaud, B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J

2005-09-16

154

Measurement of gamma in B-+ to D(*) K-+ and B-+ to D K*-+ Decays with a Dalitz Analysis of D to Ks pi- pi+  

SciTech Connect

We present a measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} with a Dalitz plot analysis of neutral D-meson decays to the K{sub S}{sup 0} {pi}{sup -}{pi}{sup +} final state from B{sup {-+}} {yields} D{sup (*)}K{sup {-+}} and B{sup {-+}} {yields} DK*{sup {-+}} decays, using a sample of 227 million B{bar B} pairs collected by the BABAR detector. We measure {gamma} = (67 {+-} 28 {+-} 13 {+-} 11){sup o}, where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the Dalitz model uncertainty. This result suffers from a two-fold ambiguity. The contribution to the Dalitz model uncertainty due to the description of the {pi}{pi} S-wave in D{sup 0} {yields} K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}, evaluated using a K-matrix formalism, is found to be 3{sup o}.

Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

2005-08-04

155

Electrochemistry and electrogenerated chemiluminescence of ?-stacked poly(fluorenemethylene) oligomers. Multiple, interacting electron transfers.  

PubMed

The electrochemistry, spectroscopy, and electrogenerated chemiluminescence (ECL) of a series of ?-stacked poly(fluorenemethylene) oligomers (Fn, n = 1-6) were investigated. The pendant cofacially oriented fluorene moieties are essentially in contact with each other by Van der Waals interaction promoting electronic delocalization in these species. All six compounds give successive cyclic voltammetric one-electron (1e) oxidations in 1:1 acetonitrile/benzene (MeCN/Bz), and the multiple 1e transfer properties of all these compounds were confirmed by chronoamperometric experiments with an ultramicroelectrode and digital simulations. The potentials for oxidation of the successive 1e transfers can be explained in terms of electrostatic interactions among the fluorenes. The monomer (F1) shows one irreversible wave, while F2 shows two reversible 1e waves. F3 shows only two reversible 1e oxidation waves, which is consistent with the large energy to remove a third electron because of the greater electrostatic repulsion, so the third wave is shifted toward more positive potentials. Both F4 and F5 show three reversible 1e oxidation waves, while F6 shows four reversible 1e waves. The removal of the first electron from an oligomer becomes easier as n increases. The stability of the radical cations also increases with n. The removal of consecutive electrons from Fn can be correlated with the distance between fluorene moieties. No reduction peaks were observed except for some broad ones at ~-3.2 V vs SCE in THF, which is consitent with the wide highest occupied molecular orbital-lowest unoccupied molecular orbital gap in these compounds (absorbance at about 300 nm). No characteristic annihilation ECL signal was observed for these compounds in 1:1 MeCN/Bz mixed solvent. However, the ECL of F6 in the presence of the coreactant C(2)O(4)(2-) showed a long-wavelength ECL emission that was proposed to be electrolyzed byproduct from the radical cation. PMID:22946643

Qi, Honglan; Chang, Jinho; Abdelwahed, Sameh H; Thakur, Khushabu; Rathore, Rajendra; Bard, Allen J

2012-10-01

156

CDF Grid computing and the decay X(3872) ---> J/psi pi+ pi- with J/psi ---> e+ e-  

SciTech Connect

The main aim of physics research is to obtain a consistent description of nature leading to a detailed understanding of the phenomena observed in experiments. The field of particle physics focuses on the discovery and understanding of the fundamental particles and the forces by which they interact with each other. Using methods from group theory, the present knowledge can be mathematically described by the so-called ''Standard Model'', which interprets the fundamental particles (quarks and leptons) as quantum-mechanical fields interacting via the electromagnetic, weak and strong force. These interactions are mediated via gauge particles such as the photon (for the electromagnetic force), W{sup {+-}} and Z{sup 0} (for the weak force) and gluons (for the strong force). Gravitation is not yet included in this description as it presently cannot be formulated in a way to be incorporated in the Standard Model. However, the gravitational force is negligibly small on microscopic levels. The validity of this mathematical approach is tested experimentally by accelerating particles such as electrons and protons, as well as their antiparticles, to high energies and observing the reactions as these particles collide using sophisticated detectors. Due to the high energy of the particles involved, these detectors need to be as big as a small house to allow for precision measurements. Comparing the predictions from theory with the analyzed reactions observed in these collisions, the Standard Model has been established as a well-founded theory. Precision measurements from the four experiments (Aleph, Delphi, Opal, L3) the Large Electron Positron collider (LEP), operated at CERN during the years 1989-2000, allow the determination of the Standard Model parameters with enormous accuracy.

Kerzel, Ulrich; /Karlsruhe U., EKP

2005-11-01

157

Carbon dioxide interaction with isolated imidazole or attached on gold clusters and surface: competition between ? H-bond and ? stacking interaction.  

PubMed

Using first principle methodologies, we investigate the subtle competition between ? H-bond and ? stacking interaction between CO2 and imidazole either isolated, adsorbed on a gold cluster or adsorbed on a gold surface. These computations are performed using MP2 as well as dispersion corrected density functional theory (DFT) techniques. Our results show that the CO2 interaction goes from ?-type stacking into ?-type when CO2 interacts with isolated imidazole and Au clusters or surface. The balance between both types of interactions is found when an imidazole is attached to a Au20 gold cluster. Thus, the present study has great significance in understanding and controlling the structures of weakly-bound molecular systems and materials, where hydrogen bonding and van der Waals interactions are competing. The applications are in the fields of the control of CO2 capture and scattering, catalysis and bio- and nanotechnologies. PMID:24833261

Prakash, Muthuramalingam; Mathivon, Kévin; Benoit, David M; Chambaud, Gilberte; Hochlaf, Majdi

2014-05-28

158

Base-base and deoxyribose-base stacking interactions in B-DNA and Z-DNA: a quantum-chemical study.  

PubMed Central

Base-stacking interactions in canonical and crystal B-DNA and in Z-DNA steps are studied using the ab initio quantum-chemical method with inclusion of electron correlation. The stacking energies in canonical B-DNA base-pair steps vary from -9.5 kcal/mol (GG) to -13.2 kcal/mol (GC). The many-body nonadditivity term, although rather small in absolute value, influences the sequence dependence of stacking energy. The base-stacking energies calculated for CGC and a hypothetical TAT sequence in Z-configuration are similar to those in B-DNA. Comparison with older quantum-chemical studies shows that they do not provide even a qualitatively correct description of base stacking. We also evaluate the base-(deoxy)ribose stacking geometry that occurs in Z-DNA and in nucleotides linked by 2',5'-phosphodiester bonds. Although the molecular orbital analysis does not rule out the charge-transfer n-pi* interaction of the sugar 04' with the aromatic base, the base-sugar contact is stabilized by dispersion energy similar to that of stacked bases. The stabilization amounts to almost 4 kcal/mol and is thus comparable to that afforded by normal base-base stacking. This enhancement of the total stacking interaction could contribute to the propensity of short d(CG)n sequences to adopt the Z-conformation. Images FIGURE 2 FIGURE 4

Sponer, J; Gabb, H A; Leszczynski, J; Hobza, P

1997-01-01

159

Observation and analysis of the 1660 MeV 3pi-resonance ``A3'' in 8 GeV\\/c pi+p interactions  

Microsoft Academic Search

The production of the 1660 MeV 3pi-resonance called the A3 is studied in 8 GeV\\/c pi+p interactions. Its mass and width are found to be (1660 +\\/- 16) MeV and (115 +\\/- 45) MeV, respectively. The cross section for pi+p --> p A3+ --> p(pi+pi+pi-) is found to be (46 +\\/- 15) mub. The differential cross section has a slope

J. Bartsch; E. Keppel; G. Kraus; R. Speth; N. Tsanos; C. Grote; K. Lanius; S. Nowak; E. Ryseck; H. Böttcher; V. T. Cocconi; J. D. Hansen; G. Kellner; U. Kruse; A. Mihul; D. R. O. Morrison; V. I. Moskalev; H. Tøfte

1968-01-01

160

Study of the S-wave K(pi) --> Amplitude Using the Decay D+ --> K-pi+pi+  

SciTech Connect

In this work the S-wave component of the K{pi} amplitude from decay of D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +} it is directly measured. The data come from the Fermilab E831/FOCUS experiment. The amplitude measurement is made using the partial wave analysis without any preliminary assumption about the nature of the S-wave component of the K{pi} system. The phase and magnitude of the S-wave amplitude are generic functions to be determined directly through the Dalitz plot fit. For the sake of comparison, our results the same decay is analyzed using the isobar model, which is the standard way to analyze the Dalitz plot. The data fit obtained with the partial wave analysis is better than the data fit from the isobar model. The phase variation with respect to the invariant mass K{pi} is compared with the measurement of the phase {delta}{sub I=1/2}{sup 0} (m{sub K{pi}}) from K{pi} {yields} K{pi} scattering. The difference between both analysis is discussed considering: a difference in the composition of the isospin components I = 1/2 and I = 3/2 of the K{pi} system between D{sup +} decay and the K{pi} {yields} K{pi} scattering; and the final state interaction involving all particles from decay.

Machado, Ana Amelia Bergamini; ,

2007-02-01

161

Center motions of nonoverlapping condensates coupled by long-range dipolar interaction in bilayer and multilayer stacks  

Microsoft Academic Search

We investigate the effect of anisotropic and long-range dipole-dipole interaction (DDI) on the center motions of nonoverlapping Bose-Einstein condensates in bilayer and multilayer stacks. In the bilayer, it is shown analytically that while DDI plays no role in the in-phase modes of center motions of condensates, out-of-phase mode frequency ({sub o}) depends crucially on the strength of DDI (a{sub d}).

Chao-Chun Huang; Wen-Chin Wu

2010-01-01

162

Center motions of nonoverlapping condensates coupled by long-range dipolar interaction in bilayer and multilayer stacks  

Microsoft Academic Search

We investigate the effect of anisotropic and long-range dipole-dipole interaction (DDI) on the center motions of nonoverlapping Bose-Einstein condensates in bilayer and multilayer stacks. In the bilayer, it is shown analytically that while DDI plays no role in the in-phase modes of center motions of condensates, out-of-phase mode frequency (omegao) depends crucially on the strength of DDI (ad). At the

Chao-Chun Huang; Wen-Chin Wu

2010-01-01

163

The effects of the ?-? stacking interactions on the patterns of gold nanoparticles formed at the air-water interface  

NASA Astrophysics Data System (ADS)

Benzyl-n-hexadecyl dimethylammonium chloride (BHDC) monolayer-stabilized gold nanoparticles were synthesized in a two-phase liquid-liquid system and found to self-assemble into varied structures under the control of temperature at the air-water interface. It has been demonstrated that the ?-? stacking interactions between the capping agent molecules significantly affect the formation of the unique patterns. A possible mechanism based on Marangoni-Bénard convection in the evaporating droplets and ?-? stacking interactions was proposed. Four surfactants with similar structures: N-hexadecyl-N-methylpyrrolidinium bromide (C16MPB), 1-hexadecyl-3-methylimidazolium bromide (C16mimBr), 1-(2,4,6-trimethylphenyl)-3-hexadecylimidazolium bromide (C16pimBr) and hexadecyltrimethylammonium bromide (CTAB) were also used to further verify the formation mechanism mentioned above.Benzyl-n-hexadecyl dimethylammonium chloride (BHDC) monolayer-stabilized gold nanoparticles were synthesized in a two-phase liquid-liquid system and found to self-assemble into varied structures under the control of temperature at the air-water interface. It has been demonstrated that the ?-? stacking interactions between the capping agent molecules significantly affect the formation of the unique patterns. A possible mechanism based on Marangoni-Bénard convection in the evaporating droplets and ?-? stacking interactions was proposed. Four surfactants with similar structures: N-hexadecyl-N-methylpyrrolidinium bromide (C16MPB), 1-hexadecyl-3-methylimidazolium bromide (C16mimBr), 1-(2,4,6-trimethylphenyl)-3-hexadecylimidazolium bromide (C16pimBr) and hexadecyltrimethylammonium bromide (CTAB) were also used to further verify the formation mechanism mentioned above. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr30286a

Jia, Han; Bai, Xiangtao; Shi, Lijuan; Lu, Fei; Zheng, Liqiang

2012-05-01

164

The collapse of stacking fault tetrahedra by interactions with gliding dislocations.  

SciTech Connect

The collapse of stacking-fault tetrahedra (SFT) by gliding dislocations was observed in in situ straining experiments in a transmission electron microscope (TEM). A stacking-fault tetrahedron was collapsed by intersection with a gliding perfect dislocation: only the base portion divided by the gliding plane of the dislocation annihilated, while the apex portion remained intact. As a result of analysis on evolution of atom configuration induced by intersection with perfect dislocation in SFT, it was found that an unusual atom configuration inevitably appeared in one of the ledges formed on stacking-fault planes, which is traditionally called I-ledge: the atoms on adjacent (111) planes were overlapping each other. The overlapping configuration provides a strong repulsive force, being a conceivable driving force to induce a chain reaction of atom displacements that collapses the SFT base portion.

Matsukawa, Yoshitaka [ORNL; Osetskiy, Yury N [ORNL; Stocks, George Malcolm [ORNL; Zinkle, Steven J [ORNL

2005-01-01

165

On ?-stacking, C-H/?, and halogen bonding interactions in halobenzene clusters: resonant two-photon ionization studies of chlorobenzene.  

PubMed

Noncovalent interactions such as hydrogen bonding, ?-? stacking, CH/? interactions, and halogen bonding play crucial roles in a broad spectrum of chemical and biochemical processes, and can exist in cooperation or competition. Here we report studies of the homoclusters of chlorobenzene, a prototypical system where ?-? stacking, CH/? interactions, and halogen bonding interactions may all be present. The electronic spectra of chlorobenzene monomer and clusters (Clbz)(n) with n = 1-4 were obtained using resonant 2-photon ionization in the origin region of the S(0)-S(1) (??*) state of the monomer. The cluster spectra show in all cases a broad spectrum whose center is redshifted from the monomer absorption. Electronic structure calculations aid in showing that the spectral broadening arises in large part from inhomogeneous sources, including the presence of multiple isomers and Franck-Condon (FC) activity associated with geometrical changes induced by electronic excitation. Calculations at the M06-2x/aug-cc-pVDZ level find in total five minimum energy structures for the dimer, four ?-stacked structures, and one T-shaped, and six representative minimum energy structures were found for the trimer. The calculated time-dependent density functional theory spectra using range-separated and meta-GGA hybrid functionals show that these isomers absorb over a range that is roughly consistent with the breadth of the experimental spectra, and the calculated absorptions are redshifted with respect to the monomer transition, in agreement with experiment. Due to the significant geometry change in the electronic transition, where for the dimer a transition from a parallel displaced to sandwich structure occurs with a reduced separation of the two monomers, significant FC activity is predicted in low frequency intermolecular modes. PMID:23163371

Muzangwa, Lloyd; Nyambo, Silver; Uhler, Brandon; Reid, Scott A

2012-11-14

166

On ?-stacking, C-H/?, and halogen bonding interactions in halobenzene clusters: Resonant two-photon ionization studies of chlorobenzene  

NASA Astrophysics Data System (ADS)

Noncovalent interactions such as hydrogen bonding, ?-? stacking, CH/? interactions, and halogen bonding play crucial roles in a broad spectrum of chemical and biochemical processes, and can exist in cooperation or competition. Here we report studies of the homoclusters of chlorobenzene, a prototypical system where ?-? stacking, CH/? interactions, and halogen bonding interactions may all be present. The electronic spectra of chlorobenzene monomer and clusters (Clbz)n with n = 1-4 were obtained using resonant 2-photon ionization in the origin region of the S0-S1 (??*) state of the monomer. The cluster spectra show in all cases a broad spectrum whose center is redshifted from the monomer absorption. Electronic structure calculations aid in showing that the spectral broadening arises in large part from inhomogeneous sources, including the presence of multiple isomers and Franck-Condon (FC) activity associated with geometrical changes induced by electronic excitation. Calculations at the M06-2x/aug-cc-pVDZ level find in total five minimum energy structures for the dimer, four ?-stacked structures, and one T-shaped, and six representative minimum energy structures were found for the trimer. The calculated time-dependent density functional theory spectra using range-separated and meta-GGA hybrid functionals show that these isomers absorb over a range that is roughly consistent with the breadth of the experimental spectra, and the calculated absorptions are redshifted with respect to the monomer transition, in agreement with experiment. Due to the significant geometry change in the electronic transition, where for the dimer a transition from a parallel displaced to sandwich structure occurs with a reduced separation of the two monomers, significant FC activity is predicted in low frequency intermolecular modes.

Muzangwa, Lloyd; Nyambo, Silver; Uhler, Brandon; Reid, Scott A.

2012-11-01

167

Effect of Stacking Interactions on the Spectra of the Monomer of PFBT: A Theoretical Study  

NASA Astrophysics Data System (ADS)

Conjugated polymers (CPs) contain one ?-conjugated backbone and functional groups that could be ionized in high dielectric media. These materials combine the semiconducting and photon harvesting properties of electronically delocalized polymers with the charge-mediated behavior of polyelectrolytes. CPs can be used as highly responsive optical sensors for chemical and biological targets. The density functional theory (DFT) and the time-dependent density functional theory (TDDFT) approach were employed to simulate the absorption and emission spectra of poly[9,9'-bis(6''-N,N,N-trimethylammonium)hexyl]fluorene-co-alt-4,7-(2,1,3-benzothiadiazole) dibromide] (PFBT) in the present study. The influences on the spectra of the monomer unit F(BT)F due to stacking with the fluorene (F) and 2,1,3-benzothiadiazole (BT) units have been explored. The results suggest that stacking lowers the excitation and emission energy, facilitating detections of the polymers.

Wang, Jing; Gu, Jiande; Leszczynski, Jerzy

2009-08-01

168

Influence of carbonaceous particles on the interaction of coal combustion stack ash with organic matter  

Microsoft Academic Search

Stack ash samples were fractionated by aerodynamic size, and the largest particle size fraction was separated into constituent particle type subfractions. Comparison of the mineral, magnetic, and carbonaceous particles showed that coked coal is responsible for the sorptivity of the large particle size fraction for carbon-14 labeled benzo(a)pyrene ((¹⁴C)BaP) and for low solvent extraction recoveries. Elevated levels of organic matter

Wayne H. Griest; Bruce A. Tomkins

1986-01-01

169

Phase Diagram of Classical Heisenberg Antiferromagnets with Four-Spin Interactions on Stacked Triangular Lattice under Magnetic field  

NASA Astrophysics Data System (ADS)

Classical Heisenberg antiferromagnet (HAF) on stacked triangular lattice is a simple and important model of frustrated systems. Although there are some candidate materials for triangular HAF, they are not ideal ones and various kinds of perturbations should be present. While it is well known that the ground state of triangular HAF is 120-degree structure, how perturbations destabilize the structure has not been well studied. In this study, we consider effects of four-spin interactions on magnetic phase diagram of triangular HAF. In fact, some real mechanisms of generating four-spin interactions have been known: higher-order electron hopping processes in Mott insulators, spin-phonon couplings, etc. We complete the magnetic phase diagrams by using Monte Carlo simulation. We will report new phases induced by four-spin interactions.

Takayoshi, Shintaro; Sato, Masahiro

2011-03-01

170

Evidence of a broad structure at an invariant mass of 4.32 GeV/c2 in the reaction e+e- --> pi+pi-psi(2S) measured at BABAR.  

PubMed

We present a measurement of the cross section of the process e(+)e(-)-->pi(+)pi(-)psi(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the SLAC PEP-II e(+)e(-) storage rings. The study is based on 298 fb(-1) of data recorded with the BABAR detector. A structure is observed in the cross section not far above threshold, near 4.32 GeV. We also investigate the compatibility of this structure with the Y(4260) previously reported by this experiment. PMID:17677767

Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Chauveau, J; Briand, H; David, P

2007-05-25

171

Theoretical investigation on the magnetic interaction of the tetrathiafulvalene–nitronyl nitroxide stacking model: possibility of organic magnetic metals and magnetic superconductors  

Microsoft Academic Search

The possibility of realizing ferromagnetic conducting crystals was investigated theoretically. Detailed theoretical calculations were carried out for tetrathiafulvalene–nitronyl nitroxide (TTF–NN) and one- and two-hole doped states of its dimer. The result indicated that the sign of effective exchange interactions between TTF–NN is largely dependent on the stacking modes and hole doping states. Well-controlled stacking and hole doping modes of spin-polarized

Fumitake Matsuoka; Yoshifumi Yamashita; Takashi Kawakami; Yasutaka Kitagawa; Yasunori Yoshioka; Kizashi Yamaguchi

2001-01-01

172

Destruction processes of large stacking fault tetrahedra induced by direct interaction with gliding dislocations  

NASA Astrophysics Data System (ADS)

The destruction process of large non-truncated stacking fault tetrahedra (SFTs) induced by gliding dislocations was examined by in situ transmission electron microscope straining experiments. Three different destruction processes were observed: a triangular Frank loop remained after the collapse (Type 1), the whole SFT was incorporated into a gliding dislocation as multiple super jog segments (Type 2), and an apex portion of the original SFT remained as a smaller SFT while the base portion was annihilated (Type 3). The remnants of Type 1 and 2 destruction processes were similar to those of previous models proposed by Kimura, indicating that these processes are based on dislocation reactions as assumed in Kimura models. On contrary, the Type 3 process, which was entirely different from Kimura models, is occasionally accompanied by vacancy migration.

Matsukawa, Y.; Osetsky, Yu. N.; Stoller, R. E.; Zinkle, S. J.

2006-06-01

173

Inclusive and semi-inclusive varrho0 production in pi+\\/pi-\\/ K +\\/ pp interactions at 147 GeV\\/c  

Microsoft Academic Search

In an experiment with the 30-inch Hybrid Spectrometer at Fermilab we have obtained the inclusive and semi-inclusive production cross sections of the varrho0 meson using a conventional background subtraction technique. Production cross sections for the varrho0 are derived as a function of the Feynman scaling variable x, and the transverse variables p {\\/t 2} and E t =( p {\\/t

M. Schouten; H. de Bock; F. Crijns; Z. Dziembowski; W. Kittel; W. Metzger; C. Pols; R. van de Walle; D. Brick; H. Rudnicka; A. M. Shapiro; M. Widgoff; R. E. Ansorge; W. W. Neale; D. R. Ward; B. M. Whyman; R. A. Burnstein; H. A. Rubin; E. D. Alyea; L. Bachman; C. Y. Chien; P. Lucas; A. Pevsner; J. T. Bober; T. A. J. Frank; E. S. Hafen; P. Haridas; D. Huang; R. J. Hulsizer; V. Kistiakowsky; P. Lutz; S. H. Oh; I. A. Pless; T. B. Stoughton; V. Suchorebrow; S. Tether; P. C. Trepagnier; Y. Wu; R. K. Yamamoto; F. Grard; J. Hanton; V. Henri; P. Herquet; J. M. Lesceux; P. Pilette; R. Windmolders; H. O. Cohn; G. Bressi; E. Calligarich; C. Castoldi; R. Dolfini; S. Ratti; R. Dimarco; P. F. Jacques; M. Kalelkar; R. J. Plano; P. Stamer; T. L. Watts; E. B. Brucker; E. L. Koller; S. Taylor; L. Berny; S. Dado; J. Goldberg; S. Toaff; G. Alexander; O. Benary; J. Grunhaus; R. Heifetz; A. Levy; W. M. Bugg; G. T. Condo; T. Handler; E. L. Hart; A. H. Rogers; Y. Eisenberg; U. Karshon; E. E. Ronat; A. Shapira; R. Yaari; G. Yekutieli; T. W. Ludlam; R. Steiner; H. D. Taft

1981-01-01

174

Absorption and resonance Raman spectra of Eu sup III (porphyrin) sub 2 sup + complexes. Oxidation-induced enhancement of porphyrin-porphyrin. pi. pi. interaction  

Microsoft Academic Search

Absorption and resonance Raman spectra are reported for the lanthanide porphyrin sandwich complexes Eu{sup III}(OEP)â{sup +}, Eu{sup III}(TPnP)â{sup +}, and Eu{sup III}(TPP)â{sup +} (OEP = octaethylporphyrin, TPnP = meso-tetrapentylporphyrin and TPP = mesotetraphenylporphyrin). These cations contain two holes in the porphyrin Ï system; consequently, they are electronically similar to solution cation dimers of the form (MOEP{sup +})â. All three of

Jinghuei Perng; J. K. Duchowski; D. F. Bocian

1991-01-01

175

Theoretical characterization of titanyl phthalocyanine as a p-type organic semiconductor: short intermolecular pi-pi interactions yield large electronic couplings and hole transport bandwidths.  

PubMed

The charge-transport properties of the triclinic phase II crystal of titanyl phthalocyanine (alpha-TiOPc) are explored within both a hopping and bandlike regime. Electronic coupling elements in convex- and concave-type dimers are calculated using density functional theory, and the relationship between molecular structure and crystal packing structure in model dimer configurations is considered. Hole transport bandwidths derived from crystal structure dimers are compared to those obtained from electronic band structure calculations; very good agreement between the two approaches is found. The calculations predict large hole bandwidths, on the order of 0.4 eV, and correspondingly very low hole reorganization energies. PMID:18205512

Norton, Joseph E; Brédas, Jean-Luc

2008-01-21

176

Stacking Interactions between Carbohydrate and Protein Quantified by Combination of Theoretical and Experimental Methods  

PubMed Central

Carbohydrate – receptor interactions are an integral part of biological events. They play an important role in many cellular processes, such as cell-cell adhesion, cell differentiation and in-cell signaling. Carbohydrates can interact with a receptor by using several types of intermolecular interactions. One of the most important is the interaction of a carbohydrate's apolar part with aromatic amino acid residues, known as dispersion interaction or CH/? interaction. In the study presented here, we attempted for the first time to quantify how the CH/? interaction contributes to a more general carbohydrate - protein interaction. We used a combined experimental approach, creating single and double point mutants with high level computational methods, and applied both to Ralstonia solanacearum (RSL) lectin complexes with ?-l-Me-fucoside. Experimentally measured binding affinities were compared with computed carbohydrate-aromatic amino acid residue interaction energies. Experimental binding affinities for the RSL wild type, phenylalanine and alanine mutants were ?8.5, ?7.1 and ?4.1 kcal.mol?1, respectively. These affinities agree with the computed dispersion interaction energy between carbohydrate and aromatic amino acid residues for RSL wild type and phenylalanine, with values ?8.8, ?7.9 kcal.mol?1, excluding the alanine mutant where the interaction energy was ?0.9 kcal.mol?1. Molecular dynamics simulations show that discrepancy can be caused by creation of a new hydrogen bond between the ?-l-Me-fucoside and RSL. Observed results suggest that in this and similar cases the carbohydrate-receptor interaction can be driven mainly by a dispersion interaction.

Necasova, Ivona; Mishra, Sushil Kumar; Komarek, Jan; Koca, Jaroslav

2012-01-01

177

Finding and visualizing nucleic acid base stacking  

Microsoft Academic Search

Base stacking is one of the primary factors stabilizing nucleic acid structure. Yet, methods for locating stacking interactions in DNA and RNA are rare and methods for displaying stacking are rarer still. We present here simple, automated procedures to search nucleic acid molecules for base-base and base-oxygen stacking and to display these interactions graphically in a manner that readily conveys

H. A. Gabb; S. R. Sanghani; C. H. Robert; C. Prévost

1996-01-01

178

Geometrical and structural characteristics of stacking fault-antiphase-boundary interactions in the massive ?m phase in a quenched Ti46.5 at.% Al alloy  

Microsoft Academic Search

The geometrical and structural characteristics of interactions between stacking faults (SFs) and antiphase boundaries (APBs) in the massive gamma (?m) phase, formed in a Ti—46.5 at.% Al alloy quenched from the high-temperature ? phase, were analysed using atomic models. The analysis confirms the transmission electron microscopy observations that SFs bound by ??121] Shockley partial dislocations of all possible types present

Ping Wang; Mukul Kumar; Vijay K. Vasudevan

2000-01-01

179

Slip stacking  

SciTech Connect

We have started beam studies for ''slip stacking''[1] in the Main Injector in order to increase proton intensity on a target for anti-proton production. It has been verified that the system for slip stacking is working with low intensity beam. For a high intensity operation, we are developing a feedback[2][3] and feedforward system.

Kiyomi Koba and James Steimel

2002-09-19

180

Stacked generalization  

Microsoft Academic Search

: This paper introduces stacked generalization, a scheme for minimizing the generalizationerror rate of one or more generalizers. Stacked generalization works by deducing the biases of thegeneralizer(s) with respect to a provided learning set. This deduction proceeds by generalizing ina second space whose inputs are (for example) the guesses of the original generalizers when taughtwith part of the learning set

David H. Wolpert

1992-01-01

181

3-Indolyl-1-naphthylmethanes: new cannabimimetic indoles provide evidence for aromatic stacking interactions with the CB(1) cannabinoid receptor.  

PubMed

A series of 1-pentyl-1H-indol-3-yl-(1-naphthyl)methanes (9-11) and 2-methyl-1-pentyl-1H-indol-3-yl-(1-naphthyl)methanes (12-14) have been synthesized to investigate the hypothesis that cannabimimetic 3-(1-naphthoyl)indoles interact with the CB(1) receptor by hydrogen bonding to the carbonyl group. Indoles 9-11 have significant (K(i)=17-23nM) receptor affinity, somewhat less than that of the corresponding naphthoylindoles (5, 15, 16). 2-Methyl-1-indoles 12-14 have little affinity for the CB(1) receptor, in contrast to 2-methyl-3-(1-naphthoyl)indoles 17-19, which have affinities comparable to those of 5, 15, 16. A cannabimimetic indene hydrocarbon (26) was synthesized and found to have K(i)=26+/-4nM. Molecular modeling and receptor docking studies of naphthoylindole 16, its 2-methyl congener (19) and indolyl-1-naphthylmethanes 11 and 14, combined with the receptor affinities of these cannabimimetic indoles, strongly suggest that these cannabinoid receptor ligands bind primarily by aromatic stacking interactions in the transmembrane helix 3-4-5-6 region of the CB(1) receptor. PMID:12538019

Huffman, John W; Mabon, Ross; Wu, Ming Jung; Lu, Jianzhong; Hart, Richard; Hurst, Dow P; Reggio, Patricia H; Wiley, Jenny L; Martin, Billy R

2003-02-20

182

Measurement of cos2beta in B;{0}-->D;{(*)}h;{0} decays with a time-dependent Dalitz plot analysis of D-->K_{s};{0}pi;{+}pi;{-}.  

PubMed

We study the time-dependent Dalitz plot of D-->K_{S};{0}pi;{+}pi;{-} in B;{0}-->D;{(*)}h;{0} decays, where h;{0} is a pi;{0}, eta, eta;{'}, or omega meson and D;{*}-->Dpi;{0}, using a data sample of 383x10;{6} Upsilon(4S)-->BB[over ] decays collected with the BABAR detector. We determine cos2beta=0.42+/-0.49+/-0.09+/-0.13, sin2beta=0.29+/-0.34+/-0.03+/-0.05, and |lambda|=1.01+/-0.08+/-0.02, where the first error is statistical, the second is the experimental systematic uncertainty, and the third, where given, is the Dalitz model uncertainty. Assuming the world average value for sin2beta and |lambda|=1, cos2beta>0 is preferred over cos2beta<0 at 86% confidence level. PMID:18233357

Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Tico, J Garra; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Pegna, D Lopes; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Vazquez, W Panduro; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Bailey, D; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N

2007-12-01

183

Study Stack  

NSDL National Science Digital Library

Developed by John Weidner, the Study Stack concept basically assists individuals to memorize information about various subjects, including geography, history, math, languages, and science. Users of the site can select one of the existing stacks, which consists of virtual study cards allowing individuals to learn at their own pace until they are satisfied with their progress. What is also particularly novel about this learning tool is that data entered for customized study stacks can be automatically displayed as a matching game, a word search puzzle, or a hangman game. So far, the site contains dozens of study stacks for each subject, with the areas dedicated to math and science containing quite a number of rather helpful stacks. With its wide range of applications, this site will be very helpful to students at different age levels and teachers who may be seeking to develop a new study tool for any number of topics or themes within a subject area.

Weidner, John

184

Two-photon, /sup 13/C and two-dimensional /sup 1/H NMR spectroscopic studies of retinyl Schiff bases, protonated Schiff bases, and Schiff base salts: evidence for a protonation induced. pi pi. * excited state level ordering reversal  

SciTech Connect

The ..pi pi..* excited singlet state manifolds of the visual chromophores, all-trans-retinylpyrrolidiniminium perchlorate (ATRSBS) and all-trans-N-retinylidene-n-butylimine:HCl (ATRPSB) are studied by using one-photon and two-photon laser spectroscopy. The goal is a better understanding of how protonation and counterion location affect level ordering in retinyl Schiff bases. Ambient temperature two-photon thermal lensing spectra indicate that ATRSBS has a lowest lying /sup 1/A/sub g/*/sup -/-like state as was observed previously for all-trans-retinal and the Schiff base of all-trans-retinal. In contrast, two-photon spectra of ATRPSB indicate that the protonated Schiff base has a lowest lying /sup 1/B/sub u/*/sup +/-like state. The origin of this level ordering reversal is analyzed by using molecular orbital theory as well as /sup 13/C and two-dimensional /sup 1/H NMR. They conclude that the relative level ordering of the low-lying covalent and ionic ..pi pi..* excited states of protonated Schiff bases and Schiff base salts is highly sensitive to counterion location (diffuseness). INDO-PSDCI molecular orbital theory is shown to be a reliable theoretical method of predicting the effect of counterion location on the one-photon and two-photon properties of retinyl protonated Schiff bases and Schiff base salts. This study provides further experimental support for the conclusions of a previous two-photon investigation of the rhodopsin binding site which demonstrated that the protein bound 11-cis-retinyl chromophore is protonated and occupies a neutral binding site.

Birge, R.R.; Murray, L.P.; Zidovetzki, R.; Knapp, H.M.

1987-04-01

185

Alternating 2,6-/3,5-substituted pyridine-acetylene macrocycles: ?-stacking self-assemblies enhanced by intermolecular dipole-dipole interaction.  

PubMed

Macrocyclic compounds consisting of three 2,6-pyridylene and three 3,5-pyridylene units linked by acetylene bonds were synthesized by a Sonogashira reaction. The X-ray structures showed ?-stacked pairs of two macrocycles, in which a 2,6-pyridylene unit of the one molecule overlaps a 3,5-pyridylene of the other molecule because of dipole-dipole interaction. Atomic force microscope (AFM) measurements revealed fibril structures indicating the stacking of the rigid planar macrocycles. Hydrogen-bonding ability of the macrocyclic inside was demonstrated by the addition of octyl ?-D-glucopyranoside. PMID:24446734

Abe, Hajime; Ohtani, Kohei; Suzuki, Daiki; Chida, Yusuke; Shimada, Yuta; Matsumoto, Shinya; Inouye, Masahiko

2014-02-01

186

Investigating the binding interactions of galantamine with ?-amyloid peptide.  

PubMed

The anti-Alzheimer's agent galantamine is known to possess anti-amyloid properties. However the exact mechanisms are not clear. We studied the binding interactions of galantamine with amyloid peptide dimer (A?(1-40)) through molecular docking and molecular dynamics simulations. Galantamine's binding site within the amyloid peptide dimer was identified by docking experiments and the most stable complex was analyzed by molecular dynamics simulation. These studies show that galantamine was interacting with the central region of the amyloid dimer (Lys16-Ala21) and the C-terminal region (Ile31-Val36) with minimum structural drift of C? atom in those regions. Strikingly, a significant drift was observed at the turn region from Asp23-Gly29 (C? atom RMSD=9.2 Å and 11.6 Å at 50 fs and 100 fs respectively). Furthermore, galantamine's binding mode disrupts the key pi-pi stacking interaction between aromatic rings of Phe19 (chain A) and Phe19 (chain B) and intermolecular hydrogen bonds seen in unbound peptide dimer. Noticeably, the azepine tertiary nitrogen of galantamine was in close proximity to backbone CO of Leu34 (distance <3.5 Å) to stabilize the dimer conformation. In summary, the results indicate that galantamine binding to amyloid peptide dimer leads to a significant conformational change at the turn region (Asp23-Gly29) that disrupts interactions between individual ?-strands and promotes a nontoxic conformation of A?(1-40) to prevent the formation of neurotoxic oligomers. PMID:23200245

Rao, Praveen P N; Mohamed, Tarek; Osman, Wesseem

2013-01-01

187

Charged-meson pair production in gammagamma interactions  

Microsoft Academic Search

The cross section for the production of pi+pi- or K+K- pairs in gammagamma interactions is measured for mpipi between 1.7 and 3.5 GeV\\/c2 and for two intervals of gammagamma center-of-mass scattering angle. Results are compared with predictions of a QCD model.

J. Boyer; D. L. Burke; F. Butler; G. Gidal; G. S. Abrams; D. Amidei; A. R. Baden; T. Barklow; A. M. Boyarski; M. Breidenbach; P. Burchat; J. M. Dorfan; G. J. Feldman; L. Gladney; M. S. Gold; G. Goldhaber; L. J. Golding; J. Haggerty; G. Hanson; K. Hayes; D. Herrup; R. J. Hollebeek; W. R. Innes; J. A. Jaros; I. Juricic; J. A. Kadyk; D. Karlen; S. R. Klein; A. J. Lankford; R. R. Larsen; B. W. Leclaire; M. E. Levi; N. S. Lockyer; V. Lüth; C. Matteuzzi; M. E. Nelson; R. A. Ong; M. L. Perl; B. Richter; K. Riles; M. C. Ross; P. C. Rowson; T. Schaad; H. Schellman; W. B. Schmidke; P. D. Sheldon; J. R. Smith; G. H. Trilling; C. de La Vaissiere; D. R. Wood; J. M. Yelton; C. Zaiser

1986-01-01

188

Mesoscopic model parametrization of hydrogen bonds and stacking interactions of RNA from melting temperatures  

PubMed Central

Information about molecular interactions in DNA can be obtained from experimental melting temperature data by using mesoscopic statistical physics models. Here, we extend the technique to RNA and show that the new parameters correctly reproduce known properties such as the stronger hydrogen bonds of AU base pairs. We also were able to calculate a complete set of elastic constants for all 10 irreducible combinations of nearest neighbours (NNs). We believe that this is particularly useful as experimentally derived information about RNA elasticity is relatively scarce. The melting temperature prediction using the present model improves over those from traditional NN model, providing thus an alternative way to calculate these temperatures for RNA. Additionally, we calculated the site-dependent base pair oscillation to explain why RNA shows larger oscillation amplitudes despite having stronger AU hydrogen bonds.

Weber, Gerald

2013-01-01

189

?-Cooperativity effect on the base stacking interactions in DNA: is there a novel stabilization factor coupled with base pairing H-bonds?  

PubMed

The results from absolutely localized molecular orbital (ALMO)-energy decomposition analysis (EDA) and ALMO-charge transfer analysis (CTA) at M06-2X/cc-pVTZ level reveal that double-proton transfer (DPT) reactions through base pairing H-bonds have nonignorable effects on the stacking energies of dinucleotide steps, which introduces us to a novel stabilization (or destabilization) factor in the DNA duplex. Thus, intra- and inter-strand base stacking interactions are coalesced with each other mediated by H-bridged quasirings between base pairs. Changes in stacking energies of dinucleotide steps depending on the positions of H atoms are due to variations in local aromaticities of individual nucleobases, manifesting ?-cooperativity effects. CT analyses show that dispersion forces in dinucleotide steps can lead to radical changes in the redox properties of nucleobases, in particular those of adenine and guanine stacked dimers in a strand. Besides Watson-Crick rules, novel base pairing rules were propounded by considering CT results. According to these, additional base pairing through ?-stacks of nucleobases in dinucleotide steps does not cause any intrinsic oxidative damage to the associated nucleobases throughout DPT. PMID:24953339

Karab?y?k, Hande; Sevinçek, Resul; Karab?y?k, Hasan

2014-07-01

190

Controllable assembly of a three-dimensional metal-organic supramolecular framework displaying hydrogen-bonding and ?-? stacking interactions.  

PubMed

The complex poly[[aqua(?2-phthalato-?(2)O(1):O(2)){?3-2-[3-(pyridin-2-yl)-1H-pyrazol-1-yl]acetato-?(4)N(2),N(3):O:O'}{?2-2-[3-(pyridin-2-yl)-1H-pyrazol-1-yl]acetato-?(3)N(2),N(3):O}dizinc(II)] dihydrate], {[Zn2(C10H8N3O2)2(C8H4O4)(H2O)]·2H2O}n, has been prepared by solvothermal reaction of 2-[3-(pyridin-2-yl)-1H-pyrazol-1-yl]acetonitrile (PPAN) with zinc(II). Under hydrothermal conditions, PPAN is hydrolyzed to 2-[3-(pyridin-2-yl)-1H-pyrazol-1-yl]acetate (PPAA(-)). The structure determination reveals that the complex is a one-dimensional double chain containing cationic [Zn4(PPAA)4](4+) structural units, which are further extended by bridging phthalate ligands. The one-dimensional chains are extended into a three-dimensional supramolecular architecture via hydrogen-bonding and ?-? stacking interactions. PMID:24992120

Cai, Hua; Xiao, Yan Ling; Guo, Ying; Li, Jian Gang

2014-07-15

191

Heteroaromatic ?-Stacking Energy Landscapes  

PubMed Central

In this study we investigate ?-stacking interactions of a variety of aromatic heterocycles with benzene using dispersion corrected density functional theory. We calculate extensive potential energy surfaces for parallel-displaced interaction geometries. We find that dispersion contributes significantly to the interaction energy and is complemented by a varying degree of electrostatic interactions. We identify geometric preferences and minimum interaction energies for a set of 13 5- and 6-membered aromatic heterocycles frequently encountered in small drug-like molecules. We demonstrate that the electrostatic properties of these systems are a key determinant for their orientational preferences. The results of this study can be applied in lead optimization for the improvement of stacking interactions, as it provides detailed energy landscapes for a wide range of coplanar heteroaromatic geometries. These energy landscapes can serve as a guide for ring replacement in structure-based drug design.

2014-01-01

192

Geometrical and structural characteristics of stacking fault-antiphase-boundary interactions in the massive gamma m phase in a quenched Ti46.5 at.% Al alloy  

Microsoft Academic Search

The geometrical and structural characteristics of interactions between stacking faults (SFs) and antiphase boundaries (APBs) in the massive gamma (gammam) phase, formed in a Ti-46.5 at.% Al alloy quenched from the hightemperature alpha phase, were analysed using atomic models. The analysis confirms the transmission electron microscopy observations that SFs bound by 1\\/6 Shockley partial dislocations of all possible types present

Ping Wang; Mukul Kumar; Vijay K. Vasudevan

2000-01-01

193

Influence of Secondary Interactions at Graphene-Based Surfaces on the Dynamic and Mechanical Properties in Nanostructured Systems  

NASA Astrophysics Data System (ADS)

Graphene, a single atom thick sheet of densely packed carbon atoms, has gained significant interest in nanostructured materials because of its exceptional mechanical, electrical, thermal, and optical properties. Because graphene nanosheets and graphene-based nanoparticles present enormous surface areas relative to their volume, interfacial interactions at graphene-based surfaces yield a significant impact on the properties of nanostructured systems. In this dissertation, secondary interactions (e.g., pi-pi interactions and hydrogen-bonding) at graphene-based surfaces in composite systems and freestanding nanoparticle films were studied, with a focus on their influence over mechanical and dynamic properties. In polymer nanocomposite systems containing carbon nanotubes, the region of altered chain dynamics near nanotube surfaces was examined as a function of crosslink density by dynamic scanning calorimetry. Three mechanisms of altered dynamics were postulated in crosslinked systems, with diminished percolation of these effects at increasing crosslink densities due to restrictions in the length scale of chain rearrangements. In-depth fracture analysis of a polymer nanocomposite containing carbon nanofibers with a stacked-cup structure pointed to the first observation of sacrificialbonding behavior in the inorganic phase of composite systems. Either continuous unraveling or discrete splaying of the coiled graphene sheets were found to dissipate energy by overcoming the relatively weak pi-pi interactions between stacked layers, yielding significant toughening at low nanofiber contents. Incorporation of these nanofibers into carbon-fiber-reinforced composites yielded mechanical enhancements in matrix-dominated properties while improving transverse electrical conductivity. Finally, the formation mechanism of freestanding graphene oxide films (or papers) fabricated by vacuum-assisted filtration of aqueous colloidal suspensions was examined as a function of both film thickness and nanosheet carbon-to-oxygen (C/O) ratio. The former was determined to impact the robustness of interlamellar contacts by means of varying degrees of compaction, resulting in brittle and tough films for intimate and loose interlamellar contacts, respectively. The mechanical response of GO papers was found to be fairly insensitive to oxidation state at low C/O ratios due to oversaturation of the hydrogen-bonding network, whereas loss of mechanical integrity was found at high C/O ratios due to lower availability of surface functional groups to form a robust hydrogen-bonding network.

Palmeri, Marc J.

194

Electronic interactions between {pi}-stacked DNA base pairs and diphenylacetylene-4,4{prime}-dicarboxamide in hairpin DNA  

SciTech Connect

The {pi}-stacked base pairs of B-form DNA provide a unique medium for the investigation of electron transfer. Most recent investigations of the dynamics of photoinduced electron transfer in DNA have employed probe chromophores that are {pi}-stacked with an adjacent base pair. The approach has been to use organic chromophores as linkers in hairpin-forming bis(oligo-nucleotide) conjugates. A hairpin structure in which the organic chromophore is approximately coplanar with the adjacent base pair is supported by spectroscopic studies, molecular modeling, and crystallography.

Lewis, F.D.; Liu, X.; Miller, S.E.; Wasielewski, M.R.

1999-10-20

195

Interaction potential for indium phosphide: a molecular dynamics and first-principles study of the elastic constants, generalized stacking fault and surface energies.  

PubMed

Indium phosphide is investigated using molecular dynamics (MD) simulations and density-functional theory calculations. MD simulations use a proposed effective interaction potential for InP fitted to a selected experimental dataset of properties. The potential consists of two- and three-body terms that represent atomic-size effects, charge-charge, charge-dipole and dipole-dipole interactions as well as covalent bond bending and stretching. Predictions are made for the elastic constants as a function of density and temperature, the generalized stacking fault energy and the low-index surface energies. PMID:21817375

Branicio, Paulo Sergio; Rino, José Pedro; Gan, Chee Kwan; Tsuzuki, Hélio

2009-03-01

196

Observation of a J{sup PC}=1{sup -+} Exotic Resonance in Diffractive Dissociation of 190 GeV/c {pi}{sup -} into {pi}{sup -{pi}-{pi}+}  

SciTech Connect

The COMPASS experiment at the CERN SPS has studied the diffractive dissociation of negative pions into the {pi}{sup -{pi}-{pi}+} final state using a 190 GeV/c pion beam hitting a lead target. A partial wave analysis has been performed on a sample of 420 000 events taken at values of the squared 4-momentum transfer t{sup '} between 0.1 and 1 GeV{sup 2}/c{sup 2}. The well-known resonances a{sub 1}(1260), a{sub 2}(1320), and {pi}{sub 2}(1670) are clearly observed. In addition, the data show a significant natural-parity exchange production of a resonance with spin-exotic quantum numbers J{sup PC}=1{sup -+} at 1.66 GeV/c{sup 2} decaying to {rho}{pi}. The resonant nature of this wave is evident from the mass-dependent phase differences to the J{sup PC}=2{sup -+} and 1{sup ++} waves. From a mass-dependent fit a resonance mass of (1660{+-}10{sub -64}{sup +0}) MeV/c{sup 2} and a width of (269{+-}21{sub -64}{sup +42}) MeV/c{sup 2} are deduced, with an intensity of (1.7{+-}0.2)% of the total intensity.

Alekseev, M. G.; Colantoni, M.; Denisov, O. Yu.; Maggiora, A. [Torino Section of INFN, 10125 Turin (Italy); Alexakhin, V. Yu.; Alexeev, G. D.; Efremov, A.; Finger, M. Jr.; Gavrichtchouk, O. P.; Gushterski, R.; Guskov, A.; Ivanov, O.; Ivanshin, Yu.; Komissarov, E. V.; Kroumchtein, Z. V.; Maximov, A. N.; Nagaytsev, A.; Olshevsky, A. G.; Perevalova, E.; Peshekhonov, D. V. [Joint Institute for Nuclear Research, 141980 Dubna, Moscow region (Russian Federation)

2010-06-18

197

Branching fractions and CP asymmetries in B0-->pi0pi0, B+-->pi+pi0, and B+-->K+pi0 decays and isospin analysis of the B-->pipi system.  

PubMed

Based on a sample of 227 x 10(6) BB pairs collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we measure the branching fraction B(B0-->pi(0)pi(0))=(1.17+/-0.32+/-0.10)x10(-6), and the asymmetry Cpi(0)(pi(0))=-0.12+/-0.56+/-0.06. The B0-->pi(0)pi(0) signal has a significance of 5.0 sigma. We also measure B(B+-->pi(+)pi(0))=(5.8+/-0.6+/-0.4)x10(-6), B(B+-->K+pi(0))=(12.0+/-0.7+/-0.6)x10(-6), and the charge asymmetries Api(+)(pi(0))=-0.01+/-0.10+/-0.02 and AK+(pi(0))=0.06+/-0.06+/-0.01. Using isospin relations, we find an upper bound on the angle difference |alpha-alpha(eff)| of 35 degrees at the 90% C.L. PMID:15904359

Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges-Pous, E; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Zhang, J; Zhang, L; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J

2005-05-13

198

Evidence for direct CP violation in the decay B{sup {+-}{yields}D(*)}K{sup {+-}}, D{yields}K{sub S}{sup 0{pi}+{pi}-} and measurement of the CKM phase {phi}{sub 3}  

SciTech Connect

We present a new measurement of the unitarity triangle angle {phi}{sub 3} using a Dalitz plot analysis of the K{sub S}{sup 0{pi}+{pi}-} decay of the neutral D meson produced in B{sup {+-}{yields}D(*)}K{sup {+-}} decays. The method exploits the interference between D{sup 0} and D{sup 0} to extract the angle {phi}{sub 3}, strong phase {delta}, and the ratio r of suppressed and allowed amplitudes. We apply this method to a 605 fb{sup -1} data sample collected by the Belle experiment. The analysis uses three decays: B{sup {+-}{yields}D}K{sup {+-}}, and B{sup {+-}{yields}D}*K{sup {+-}}with D*{yields}D{pi}{sup 0} and D*{yields}D{gamma}, as well as the corresponding charge-conjugate modes. From a combined maximum likelihood fit to the three modes, we obtain {phi}{sub 3}=78.4 deg. (+10.8 deg./-11.6 deg.){+-}3.6 deg. (syst){+-}8.9 deg. (model). CP conservation in this process is ruled out at the confidence level (1-CL)=5x10{sup -4}, or 3.5 standard deviations.

Poluektov, A.; Bondar, A.; Arinstein, K.; Aulchenko, V.; Eidelman, S.; Epifanov, D.; Gabyshev, N.; Garmash, A.; Kuzmin, A.; Shebalin, V.; Shwartz, B.; Usov, Y.; Vinokurova, A.; Zhilich, V.; Zhulanov, V.; Zyukova, O. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Yabsley, B. D.; Bakich, A. M.; McOnie, S.; Varvell, K. E. [School of Physics, University of Sydney, NSW 2006 (Australia)

2010-06-01

199

Quantum-mechanical computations on the electronic structure of trans-resveratrol and trans-piceatannol: a theoretical study of the stacking interactions in trans-resveratrol dimers.  

PubMed

Accurate quantum-chemical calculations based on the second-order Møller-Plesset perturbation method (MP2) and density functional theory (DFT) were performed for the first time to investigate the electronic structures of trans-resveratrol and trans-piceatannol, as well as to study the stacking interaction between trans-resveratrol molecules. Ab initio MP2 calculations performed with using standard split-valence Pople basis sets led us to conclude that these compounds have structures that deviate strongly from planarity, whereas the DFT computations for the same basis sets revealed that the equilibrium geometries of these bioactive polyphenols are planar. Furthermore, the results obtained at the MP2(full)/aug-cc-pVTZ and B3LYP/aug-cc-pVTZ levels indicated that the geometries of trans-resveratrol and trans-piceatannol are practically planar at their absolute energy minima. The relative energies of the equilibrium geometries of trans-resveratrol on its potential energy surface were computed at the MP2(full)/aug-cc-pVTZ level. According to the results obtained, a T-shaped (edge-to-phase) conformer of trans-resveratrol dimer is the most stable in vacuum. This T-shaped conformer is mainly stabilized by strong hydrogen bonding and weak C-H...? interactions. Stacked structures with parallel-displaced trans-stilbene skeletons were also found to be energetically stable. The vertical separation and twist angle dependencies of the stacking energy were investigated at the MP2(full)/aug-cc-pVTZ, B3LYP/aug-cc-pVTZ, and HF/aug-cc-pVTZ levels. The standard B3LYP functional and the Hartree-Fock method neglect long-range attractive dispersion interactions. The MP2 computations revealed that the London dispersion energy cannot be neglected at long or short distances. The stacked model considered here may be useful for predicting the quantum nature of the interactions in ?-stacked systems of other naturally occurring stilbenoids, and can help to enhance our understanding of the antioxidant and anticancer activities of trans-resveratrol. PMID:22249749

Mikulski, Damian; Molski, Marcin

2012-07-01

200

Study on the interaction between nucleic acids and cationic surfactants.  

PubMed

The interactions of nucleic acids and cationic surfactants (cetylpyridine bromide (CPB) and cetyltrimethylammonium bromide (CTMAB)) in aqueous solution have been studied using the techniques of resonance light scattering (RLS) spectroscopy, the absorption spectroscopy, zeta potential assay and NMR assignment measurement. It is considered that CPB or CTMAB can assemble on the surface of nucleic acid via electrostatic and hydrophobic forces, which results in the formation of large associate of nucleic acid-cationic surfactant and RLS enhancement of nucleic acid. Besides these forces, the pi-pi stacking force between CPB and nucleic acid also exists in the associate. In comparison with CTMAB, CPB has larger enhancement on RLS of nucleic acid, which is attributed to that the enhancement of the former is only due to the absorption of the bases of nucleic acid, while the enhancement of the latter is own to the synergetic resonance caused by the absorption of both bases of nucleic acid and the pyridyl in CPB. These results have important implication for understanding the influence of surfactants on nucleic acid functionality in life science. PMID:15261091

Liu, Rutao; Yang, Jinghe; Sun, Changxia; Wu, Xia; Li, Lei; Su, Benyu

2004-03-01

201

Diffractive stacks of metamaterial lattices with a complex unit cell: Self-consistent long-range bianisotropic interactions in experiment and theory  

NASA Astrophysics Data System (ADS)

Metasurfaces and metamaterials promise arbitrary rerouting of light using two-dimensional (2D) planar arrangements of electric and magnetic scatterers, respectively, 3D stacks built out of such 2D planes. An important problem is how to self-consistently model the response of these systems in a manner that retains dipole intuition yet does full justice to the self-consistent multiple scattering via near-field and far-field retarded interactions. We set up such a general model for metamaterial lattices of complex 2D unit cells of poly-atomic basis as well as allowing for stacking in a third dimension. In particular, each scatterer is quantified by a magnetoelectric polarizability tensor and Ewald lattice summation deals with all near-field and long-range retarded electric, magnetic, and magnetoelectric couplings self-consistently. We show in theory and experiment that grating diffraction orders of dilute split ring lattices with complex unit cells show a background-free signature of magnetic dipole response. For denser lattices experiment and theory show that complex unit cells can reduce the apparent effect of bianisotropy, i.e., the strong oblique-incidence handed response that was reported for simple split ring lattices. Finally, the method is applied to calculate transmission of finite stacks of lattices. Thereby our simple methodology allows us to trace the emergence of effective material constants when building a 3D metamaterial layer by layer, as well as facilitating the design of metasurfaces.

Kwadrin, Andrej; Koenderink, A. Femius

2014-01-01

202

The ?···? stacking interactions between homogeneous dimers of C6F(x)I((6-x)) (x = 0, 1, 2, 3, 4, and 5): a comparative study with the halogen bond.  

PubMed

The ?···? stacking interactions between homogeneous dimers of C(6)F(x)I((6-x)) (x = 0, 1, 2, 3, 4, and 5) have been investigated in detail using the state-of-the-art quantum chemistry methods. Computations clearly show that the ?···? stacking interaction between the homogeneous dimer of C(6)F(x)I((6-x)) is of the dispersion type interaction. At the same time, it is interesting to find that, for the ?···? stacking interactions between homogeneous dimers of C(6)F(x)I((6-x)), the M05-2X/def2-TZVPP computations give almost the same results as the CCSD(T)/SDD** computations. In the crystal growth and design, the formation of the ?···? stacking interactions between homogeneous dimers of C(6)F(x)I((6-x)) is always accompanied by the formation of the halogen bonds. Hence, competition and cooperation of the ?···? stacking interaction and the halogen bond have also been studied theoretically by using C(6)F(x)I((6-x)) and pyridine as coformers. At the M05-2X/def2-TZVPP theory level, it is found that the ?···? stacking interactions in C(6)F(5)I···C(6)F(5)I and C(6)F(4)I(2)···C(6)F(4)I(2) are weaker than the corresponding halogen bonds in C(6)F(5)I···NC(5)H(5) and C(6)F(4)I(2)···NC(5)H(5), and the ?···? stacking interactions in C(6)FI(5)···C(6)FI(5) and C(6)I(6)···C(6)I(6) are stronger than the corresponding halogen bonds in C(6)FI(5)···NC(5)H(5) and C(6)I(6)···NC(5)H(5), while the strengths of the ?···? stacking interactions in C(6)F(3)I(3)···C(6)F(3)I(3) and C(6)F(2)I(4)···C(6)F(2)I(4) are similar to the corresponding halogen bonds in C(6)F(3)I(3)···NC(5)H(5) and C(6)F(2)I(4)···NC(5)H(5). However, when the ?···? stacking interaction and the halogen bond coexist, we find that the formation of the halogen bond will lead to the ?···? stacking interaction much stronger, and vice versa. PMID:23214504

Wang, Weizhou; Zhang, Yu; Wang, Yi-Bo

2012-12-27

203

Stacking interactions of W271 and H275 of SeMV serine protease with W43 of natively unfolded VPg confer catalytic activity to protease.  

PubMed

N-terminal serine protease domain of Sesbania mosaic virus polyprotein, requires fused VPg for its activity. W43 of VPg mediates aromatic stacking interactions (characterized by 230 nm positive CD peak) with protease. A stretch of aromatic residues (F269, W271, Y315, and Y319) exposed in the protease domain were mutated to identify the interacting partner of W43. W271A Protease-VPg mutant showed absence of cleavage activity both in vivo and in trans, with concomitant loss of the 230 nm CD peak. F269A Protease-VPg mutant was partially active. Mutations of the tyrosines did not result in loss of protease activity or the CD peak. Interestingly, H275, though not a part of the exposed aromatic stretch, was shown to be essential for protease activity and contributed significantly to the CD peak. Hence, we conclude that W271 and H275 of the protease domain mediate aromatic stacking interactions with W43 of VPg thereby rendering the protease active. PMID:18842279

Nair, Smita; Gayathri, P; Murthy, M R N; Savithri, H S

2008-12-01

204

Finding and visualizing nucleic acid base stacking.  

PubMed

Base stacking is one of the primary factors stabilizing nucleic acid structure. Yet, methods for locating stacking interactions in DNA and RNA are rare and methods for displaying stacking are rarer still. We present here simple, automated procedures to search nucleic acid molecules for base-base and base-oxygen stacking and to display these interactions graphically in a manner that readily conveys both the location and the quality of the interaction. The method makes no a priori assumptions about relative base positions when searching for stacking, nor does it rely on empirical energy functions. This is a distinct advantage for two reasons. First, the relative contributions of the forces stabilizing stacked bases are unknown. Second, the electrostatic and hydrophobic components of base stacking are both poorly defined by existing potential energy functions. PMID:8744567

Gabb, H A; Sanghani, S R; Robert, C H; Prévost, C

1996-02-01

205

Conformational isomerism and weak molecular and magnetic interactions in ternary copper(II) complexes of [Cu(AA)L']ClO4.nH2O, where AA = L-phenylalanine and L-histidine, L' = 1,10-phenanthroline and 2,2-bipyridine, and n = 1 or 1.5: synthesis, single-crystal X-ray structures, and magnetic resonance investigations.  

PubMed

Weak molecular and magnetic exchange interactions in ternary copper(II) complexes, viz., [Cu(L-phe)(phen)(H(2)O)]ClO(4) (1), [Cu(L-phe)(bpy)(H(2)O)]ClO(4) (2), and [Cu(L-his)(bpy)]ClO(4).1.5H(2)O (3), where L-phe = L-phenylalanine, L-his = L-histidine, phen = 1,10-phenanthroline, and bpy = 2,2'-bipyridine, have been investigated. Single-crystal X-ray structures reveal that complex 2 crystallizes in a monoclinic space group P2(1), with unit cell parameters a = 7.422(7) A, b = 11.397(5) A, c = 12.610(2) A, beta = 102.10(5) degrees, V = 1043.0(11) A(3), Z = 2, R = 0.0574, and R(w) = 0.1657. Complex 3 crystallizes in a monoclinic space group C2, with a = 18.834(6) A, b = 10.563(4) A, c = 11.039(3) A, beta = 115.23(2) degrees, V = 1986.6(11) A(3), Z = 4, R = 0.0466, and R(w) = 0.1211. Molecules of 2, in the solid state, are self-assembled via weak intra- and intermolecular pi-pi stacking and H-bonding interactions. Molecules of 3 exhibit intermolecular dimeric association with the Cu.Cu separation being 3.811 A. X-ray structures and (1)H NMR studies reveal conformational isomerism in both solid and liquid states of complexes 1 and 2. The aromatic side chain of L-phe in 1 and 2 adopts either a "folded" (A) or an "extended" (B) conformation. Variable-temperature (1)H NMR and spin lattice relaxation measurements point out interconversion between conformations A and B at temperatures above 323 K. The change in molecular conformation induces a change in the electron density at the site of copper and band gap energy between HOMO and LUMO orbitals. Interestingly, in spite of paramagnetic nature, complexes 1 and 2 are amenable for both EPR and (1)H NMR spectroscopic studies. Single-crystal EPR spectra of 2 in three orthogonal planes are consistent with three-dimensional magnetic behavior. Intramolecular exchange dominates the dipolar interactions. The EPR spectra of 3 correspond to weak magnetic interactions between associated dimeric units. The structural and magnetic resonance investigations together reveal that the weak pi-pi stacking interactions are the electronic pathways for magnetic interactions in 1-3. PMID:11487335

Subramanian, P S; Suresh, E; Dastidar, P; Waghmode, S; Srinivas, D

2001-08-13

206

Edge states in stacked nanographene  

NASA Astrophysics Data System (ADS)

Nanocarbon materials are investigated intensively. In this paper, the edge-state in nanographene materials with zigzag edges is studied theoretically. In particular, while the inter-layer interactions are considered, we prove that edge states exist at the energy of the Dirac point in the doubly stacked nanographene, and in the case of the infinitely-wide lower layer case. This property applies both for the A-B and A-C stackings.

Harigaya, Kikuo

2012-12-01

207

A Survey of Aspartate-Phenylalanine and Glutamate-Phenylalanine Interactions in the Protein Data Bank: Searching for Anion-pi Pairs  

SciTech Connect

Protein structures are stabilized using noncovalent interactions. In addition to the traditional noncovalent interactions, newer types of interactions are thought to be present in proteins. One such interaction, an anion-{pi} pair, in which the positively charged edge of an aromatic ring interacts with an anion, forming a favorable anion-quadrupole interaction, has been previously proposed [Jackson, M. R., et al. (2007) J. Phys. Chem. B111, 8242-8249]. To study the role of anion-{pi} interactions in stabilizing protein structure, we analyzed pairwise interactions between phenylalanine (Phe) and the anionic amino acids, aspartate (Asp) and glutamate (Glu). Particular emphasis was focused on identification of Phe-Asp or -Glu pairs separated by less than 7 {angstrom} in the high-resolution, nonredundant Protein Data Bank. Simplifying Phe to benzene and Asp or Glu to formate molecules facilitated in silico analysis of the pairs. Kitaura-Morokuma energy calculations were performed on roughly 19000 benzene-formate pairs and the resulting energies analyzed as a function of distance and angle. Edgewise interactions typically produced strongly stabilizing interaction energies (-2 to -7.3 kcal/mol), while interactions involving the ring face resulted in weakly stabilizing to repulsive interaction energies. The strongest, most stabilizing interactions were identified as preferentially occurring in buried residues. Anion-{pi} pairs are found throughout protein structures, in helices as well as {beta} strands. Numerous pairs also had nearby cation-{pi} interactions as well as potential {pi}-{pi} stacking. While more than 1000 structures did not contain an anion-{pi} pair, the 3134 remaining structures contained approximately 2.6 anion-{pi} pairs per protein, suggesting it is a reasonably common motif that could contribute to the overall structural stability of a protein.

Philip, Vivek M [ORNL; Harris, Jason B [ORNL; Adams, Rachel M [ORNL; Nguyen, Don [University of Tennessee; Spiers, Jeremy D [ORNL; Baudry, Jerome Y [ORNL; Howell, Elizabeth E [ORNL; Hinde, Robert J [ORNL

2011-01-01

208

Fuel cell stack arrangements  

DOEpatents

Arrangements of stacks of fuel cells and ducts, for fuel cells operating with separate fuel, oxidant and coolant streams. An even number of stacks are arranged generally end-to-end in a loop. Ducts located at the juncture of consecutive stacks of the loop feed oxidant or fuel to or from the two consecutive stacks, each individual duct communicating with two stacks. A coolant fluid flows from outside the loop, into and through cooling channels of the stack, and is discharged into an enclosure duct formed within the loop by the stacks and seals at the junctures at the stacks.

Kothmann, Richard E. (Churchill Boro, PA); Somers, Edward V. (Murrysville, PA)

1982-01-01

209

An enhanced electronic state in ZnTPP induced by interaction with solvation : a multiple-scattering calculation of x-ray absorption near-edge spectra.  

SciTech Connect

Metalloporphyrins (MP) are important for a wide variety of biological processes and photosynthesis and have been intensively investigated by x-ray absorption spectroscopy. The typical metal K-edge XANES spectra of the square-planar MTPP show a very sharp peak on the rising edge of the main absorption peak, which was assigned to 1s {yields} 4p{sub z} electronic transition. We carried out a series of multiple-scattering calculations of porphyrin molecules and found that this peak can be greatly enhanced due to the {pi}-{pi} stacking of phenyl rings below and above the porphyrin plane. Density of state calculations confirmed that the emergence of this electronic state is due to the interaction of the 4p{sub z} orbital of the metal with {pi} orbitals of an aromatic solvent molecule with its plane parallel with the macrocycle. This XANES feature of metalloporphyrins can be used to investigate the solvent-solute interactions with presumed non-ligating solvent.

Liu, T.; Chen, L. X.; Chemistry; Chinese Academy of Sciences

2005-01-01

210

Two-dimensional self-assembly of 1-pyrylphosphonic acid: transfer of stacks on structured surface.  

PubMed

Strong hydrogen bonding and pi-pi stacking between 1-pyrylphosphonic acid (PYPA) molecules were exploited to create self-assembled two-dimensional supramolecular structures. Polycrystalline films of these laminate crystalline PYPA bilayers were easily deposited onto the solid supports through a simple spin-coating technique. Atomic force microscopy (AFM), scanning tunneling microscopy (STM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-vis absorption, and fluorescence spectroscopy reveal that processing parameters, such as solvent, concentration, and surface of the substrate, are critical factors in determining the final morphology of the stacked film. Robust laminate structures could be obtained only when short alkyl chain protic solvents (methanol or ethanol) and a nonhydrophobic substrate surface were used. Polycrystalline films were formed through the nucleation and growth of PYPA molecules into laminate structures at the air/solvent interface before they land on the substrate during the spin-coating process. These films possess good mechanical properties and were easily transferred onto a SiO2/Si substrate that was patterned with Au electrodes without breaking their crystalline structures. The successful transfer of the laminate crystals allows us to probe their electrical properties through a field effect transistor device. A gating effect on the charge transport of the stacked films indicates that PYPA laminate crystal possesses p-typed semiconductor characteristics. PMID:16637633

Yip, Hin-Lap; Ma, Hong; Jen, Alex K-Y; Dong, Jianchun; Parviz, Babak A

2006-05-01

211

?-? stacking tackled with density functional theory  

PubMed Central

Through comparison with ab initio reference data, we have evaluated the performance of various density functionals for describing ?-? interactions as a function of the geometry between two stacked benzenes or benzene analogs, between two stacked DNA bases, and between two stacked Watson–Crick pairs. Our main purpose is to find a robust and computationally efficient density functional to be used specifically and only for describing ?-? stacking interactions in DNA and other biological molecules in the framework of our recently developed QM/QM approach "QUILD". In line with previous studies, most standard density functionals recover, at best, only part of the favorable stacking interactions. An exception is the new KT1 functional, which correctly yields bound ?-stacked structures. Surprisingly, a similarly good performance is achieved with the computationally very robust and efficient local density approximation (LDA). Furthermore, we show that classical electrostatic interactions determine the shape and depth of the ?-? stacking potential energy surface. Figure Additivity approximation for the ?-? interaction between two stacked Watson–Crick base pairs in terms of pairwise interactions between individual bases Electronic supplementary material The online version of this article (doi:10.1007/s00894-007-0239-y) contains supplementary material, which is available to authorized users.

Swart, Marcel; van der Wijst, Tushar; Fonseca Guerra, Celia

2007-01-01

212

Semiempirical study of perturbations of the landé g factors of electronic-vibrational-rotational levels of hydrogen: IV. The I 1?<Stack> g - Stack>, R 1?<Stack> g - Stack>, J 1?<Stack> g - Stack>, and S 1?<Stack> g - Stack> states of the H2 and D2 molecules  

NASA Astrophysics Data System (ADS)

Values of the Landé g factors are obtained for the first time for rovibronic levels of the (3d)J 1?<Stack> g - Stack> state of the D2 molecule and of the (4d)S 1?<Stack> g - Stack> state of the H2 and D2 molecules. Semiempirical values of these quantities are obtained for the first time for the (4d)R 1?<Stack> g - Stack> state of the H2 molecule and the (3d)I 1?<Stack> g - Stack> and (4d)R 1?<Stack> g - Stack> states of the D2 molecule. These values are determined in terms of the nonadiabatic model, which takes into account the interaction between the nd?1?g and nd?1?g (n = 3 and 4) states in the approximation of pure precession, with the use of the semiempirical values obtained by us for the expansion coefficients of wave functions in the adiabatic basis functions and the results of our numerical calculation of overlap integrals of the vibrational wave functions of these states. The values thus obtained are in good agreement with the data available in the literature. It is found that the interference effects of coupling of the nd?1?g and nd?1?g states lead to significant perturbations of the dependences of the g factors of vibronic levels on the rotational quantum number as compared to the adiabatic results. These perturbations are regular (reaching a factor of nine) for the I 1?<Stack> g - Stack> and R 1?<Stack> g - Stack> states and irregular (reaching a factor of 50) for the J 1?<Stack> g - Stack> and S 1?<Stack> g - Stack> states. The nonadiabatic values of g factors obtained in our previous studies for the H2, HD, and D2 molecules in the i 3?<Stack> g - Stack> and j 3?<Stack> g - Stack> states are improved by an additional inclusion of adiabatic effects. It is established that the effect of the electron spin on the g factor values for rovibronic levels of the 3d?<Stack> g - Stack> states is significant and reaches 25% for H2 and 130% for D2.

Astashkevich, S. A.

2007-02-01

213

?-? stacking tackled with density functional theory  

Microsoft Academic Search

Through comparison with ab initio reference data, we have evaluated the performance of various density functionals for describing\\u000a ?-? interactions as a function of the geometry between two stacked benzenes or benzene analogs, between two stacked DNA bases,\\u000a and between two stacked Watson–Crick pairs. Our main purpose is to find a robust and computationally efficient density functional\\u000a to be used

Marcel Swart; Tushar van der Wijst; Célia Fonseca Guerra; F. Matthias Bickelhaupt

2007-01-01

214

Time-Resolved Fluorescence Imaging Reveals Differential Interactions of N-Glycan Processing Enzymes across the Golgi Stack in Planta1[W][OA  

PubMed Central

N-Glycan processing is one of the most important cellular protein modifications in plants and as such is essential for plant development and defense mechanisms. The accuracy of Golgi-located processing steps is governed by the strict intra-Golgi localization of sequentially acting glycosidases and glycosyltransferases. Their differential distribution goes hand in hand with the compartmentalization of the Golgi stack into cis-, medial-, and trans-cisternae, which separate early from late processing steps. The mechanisms that direct differential enzyme concentration are still unknown, but the formation of multienzyme complexes is considered a feasible Golgi protein localization strategy. In this study, we used two-photon excitation-Förster resonance energy transfer-fluorescence lifetime imaging microscopy to determine the interaction of N-glycan processing enzymes with differential intra-Golgi locations. Following the coexpression of fluorescent protein-tagged amino-terminal Golgi-targeting sequences (cytoplasmic-transmembrane-stem [CTS] region) of enzyme pairs in leaves of tobacco (Nicotiana spp.), we observed that all tested cis- and medial-Golgi enzymes, namely Arabidopsis (Arabidopsis thaliana) Golgi ?-mannosidase I, Nicotiana tabacum ?1,2-N-acetylglucosaminyltransferase I, Arabidopsis Golgi ?-mannosidase II (GMII), and Arabidopsis ?1,2-xylosyltransferase, form homodimers and heterodimers, whereas among the late-acting enzymes Arabidopsis ?1,3-galactosyltransferase1 (GALT1), Arabidopsis ?1,4-fucosyltransferase, and Rattus norvegicus ?2,6-sialyltransferase (a nonplant Golgi marker), only GALT1 and medial-Golgi GMII were found to form a heterodimer. Furthermore, the efficiency of energy transfer indicating the formation of interactions decreased considerably in a cis-to-trans fashion. The comparative fluorescence lifetime imaging of several full-length cis- and medial-Golgi enzymes and their respective catalytic domain-deleted CTS clones further suggested that the formation of protein-protein interactions can occur through their amino-terminal CTS region.

Schoberer, Jennifer; Liebminger, Eva; Botchway, Stanley W.; Strasser, Richard; Hawes, Chris

2013-01-01

215

B^0 to \\pi^+ \\pi^- \\pi^0Time Dependent Dalitz Analysis at BaBar  

SciTech Connect

The author presents here results of a time-dependent analysis of the Dalitz structure of neutral B meson decays to {pi}{sup +}{pi}{sup -}{pi}{sup 0} from a dataset of 346 million B{bar B} pairs collected at the {Upsilon}(4S) center of mass energy by the BaBar detector at the SLAC PEP-II e{sup +}e{sup -} accelerator. No significant CP violation effects are observed and 68% confidence interval is derived on the weak angle {alpha} to be [75,152].

Cavoto, Gianluca

2007-04-06

216

Partial Wave Analysis of the pi+pi+pi– system in photo-production at CLAS  

SciTech Connect

A partial Wave Analysis (PWA) has been performed on the first high statistics sample of 84,000 {pi}{sup +}{pi}{sup +}{pi}{sup -} photo-produced events from the reaction {gamma} p {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -} n with the tagged photon beam in the 4.8-5.4 GeV energy range. The data were collected from the E01-017 (g6c) running of CLAS in Aug.-Sep. 2001 at Jefferson Lab.

Mina Nozar

2006-07-01

217

Diffractive Dissociation into pi-pi-pi+ Final States at COMPASS  

Microsoft Academic Search

QCD predicts gluonic excitations like hybrids to contribute to the meson spectrum in addition to qq pair configurations. The most promising way to identify such states is the search for JPC quantum number combinations which are forbidden in the constituent quark model. The fixed target COMPASS experiment at CERN offers the opportunity to search for such states in the light

Florian Haas

2010-01-01

218

Diffractive Dissociation into pi-pi-pi+ Final States at COMPASS  

Microsoft Academic Search

QCD predicts gluonic excitations like hybrids to contribute to the meson spectrum in addition to qq pair configurations. The most promising way to identify such states is the search for JPC quantum number combinations which are forbidden in the constituent quark model. The fixed target COMPASS experiment at CERN offers the opportunity to search for such states in the light

Florian Haas

2011-01-01

219

Recognition of O6-benzyl-2'-deoxyguanosine by a perimidinone-derived synthetic nucleoside: a DNA interstrand stacking interaction.  

PubMed

The 2'-deoxynucleoside containing the synthetic base 1-[(2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)-tetrahydrofuran-2-yl)-1H-perimidin-2(3H)-one] (dPer) recognizes in DNA the O(6)-benzyl-2'-deoxyguanosine nucleoside (O(6)-Bn-dG), formed by exposure to N-benzylmethylnitrosamine. Herein, we show how dPer distinguishes between O(6)-Bn-dG and dG in DNA. The structure of the modified Dickerson-Drew dodecamer (DDD) in which guanine at position G(4) has been replaced by O(6)-Bn-dG and cytosine C(9) has been replaced with dPer to form the modified O(6)-Bn-dG:dPer (DDD-XY) duplex [5'-d(C(1)G(2)C(3)X(4)A(5)A(6)T(7)T(8)Y(9)G(10)C(11)G(12))-3']2 (X = O(6)-Bn-dG, Y = dPer) reveals that dPer intercalates into the duplex and adopts the syn conformation about the glycosyl bond. This provides a binding pocket that allows the benzyl group of O(6)-Bn-dG to intercalate between Per and thymine of the 3'-neighbor A:T base pair. Nuclear magnetic resonance data suggest that a similar intercalative recognition mechanism applies in this sequence in solution. However, in solution, the benzyl ring of O(6)-Bn-dG undergoes rotation on the nuclear magnetic resonance time scale. In contrast, the structure of the modified DDD in which cytosine at position C(9) is replaced with dPer to form the dG:dPer (DDD-GY) [5'-d(C(1)G(2)C(3)G(4)A(5)A(6)T(7)T(8)Y(9)G(10)C(11)G(12))-3']2 duplex (Y = dPer) reveals that dPer adopts the anti conformation about the glycosyl bond and forms a less stable wobble pairing interaction with guanine. PMID:23748954

Kowal, Ewa A; Lad, Rahul R; Pallan, Pradeep S; Dhummakupt, Elizabeth; Wawrzak, Zdzislaw; Egli, Martin; Sturla, Shana J; Stone, Michael P

2013-08-01

220

Recognition of O6-benzyl-2?-deoxyguanosine by a perimidinone-derived synthetic nucleoside: a DNA interstrand stacking interaction  

PubMed Central

The 2?-deoxynucleoside containing the synthetic base 1-[(2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)-tetrahydrofuran-2-yl)-1H-perimidin-2(3H)-one] (dPer) recognizes in DNA the O6-benzyl-2?-deoxyguanosine nucleoside (O6-Bn-dG), formed by exposure to N-benzylmethylnitrosamine. Herein, we show how dPer distinguishes between O6-Bn-dG and dG in DNA. The structure of the modified Dickerson–Drew dodecamer (DDD) in which guanine at position G4 has been replaced by O6-Bn-dG and cytosine C9 has been replaced with dPer to form the modified O6-Bn-dG:dPer (DDD-XY) duplex [5?-d(C1G2C3X4A5A6T7T8Y9G10C11G12)-3?]2 (X = O6-Bn-dG, Y = dPer) reveals that dPer intercalates into the duplex and adopts the syn conformation about the glycosyl bond. This provides a binding pocket that allows the benzyl group of O6-Bn-dG to intercalate between Per and thymine of the 3?-neighbor A:T base pair. Nuclear magnetic resonance data suggest that a similar intercalative recognition mechanism applies in this sequence in solution. However, in solution, the benzyl ring of O6-Bn-dG undergoes rotation on the nuclear magnetic resonance time scale. In contrast, the structure of the modified DDD in which cytosine at position C9 is replaced with dPer to form the dG:dPer (DDD-GY) [5?-d(C1G2C3G4A5A6T7T8Y9G10C11G12)-3?]2 duplex (Y = dPer) reveals that dPer adopts the anti conformation about the glycosyl bond and forms a less stable wobble pairing interaction with guanine.

Kowal, Ewa A.; Lad, Rahul R.; Pallan, Pradeep S.; Dhummakupt, Elizabeth; Wawrzak, Zdzislaw; Egli, Martin; Sturla, Shana J.; Stone, Michael P.

2013-01-01

221

Fifty years of stacking  

NASA Astrophysics Data System (ADS)

Common-Mid-Point (CMP) stacking is a major process to enhance signal-to-noise ratio in seismic data. Since its appearance fifty years ago, CMP stacking has gone through different phases of prosperity and negligence within the geophysical community. During those times, CMP stacking developed from a simple process of averaging into a sophisticated process that involves complicated mathematics and state-of-the-art computation. This article summarizes the basic principles, assumptions, and violations related to the CMP stacking technique, presents a historical overview on the development stages of CMP stacking, and discusses its future potentiality.

Rashed, Mohamed

2014-06-01

222

Evidence for higher twist mechanisms in prompt varrho0-meson production at PT > 2 GeV\\/c in 300 GeV\\/c PiN interactions  

Microsoft Academic Search

The production of varrho0 mesons in hadronic interactions is investigated at high transverse momentum (pT > 2 GeV\\/c). The data come from a sample of Pi-N interactions at 300 GeV\\/c obtained at the CERN OMEGA spectrometer, requiring a varrho0-->Pi+Pi- with pT (pair) > 2 GeV\\/c to recoil against an opposite particle with pT (opposite) > 1 GeV\\/c . The signal\\/(signal

M. Benayoun; W. Beusch; I. J. Bloodworth; A. J. Burns; J. N. Carney; B. R. French; B. Ghidini; Y. Goldschmidt-Clermont; G. Ingelman; A. Jacholkowski; J. Kahane; J. B. Kinson; K. Knudson; J. C. Lassalle; V. Lenti; Ph. Leruste; A. Malamant; J. L. Narjoux; F. Navach; C. Neaume; A. Palano; R. Petronzio; M. Pimenta; I. C. Print; E. Quercigh; M. Sené; R. Sené; H. R. Shaylor; M. Stassinaki; Z. Strachman; M. T. Trainor; G. Vassiliadis; O. Villalobos Baillie; M. F. Votruba; G. Zito; R. Zitoun

1987-01-01

223

A precise new KLOE measurement of |F{sub {pi}}|{sup 2} with ISR events and determination of {pi}{pi} contribution to a{sub {mu}} for 0.592  

SciTech Connect

The KLOE experiment at the DA{phi}NE {phi}-factory has performed a new precise measurement of the pion form factor using Initial State Radiation events, with photons emitted at small polar angle. Results based on an integrated luminosity of 240 pb{sup -1} and extraction of the {pi}{pi} contribution to a{sub {mu}} in the mass range 0.35

Venanzoni, G. [Laboratori Nazionali di Frascati dell'INFN, Via E. Fermi 40, I-00044 Frascati (Italy)

2009-12-17

224

Computational Science - Stack Exchange  

NSDL National Science Digital Library

This is a free, community driven Q&A for scientists using computers to solve scientific problems. It is a part of the Stack Exchange network of Q&A websites, and it was created through the open democratic process defined at Stack Exchange Area 51.

225

Solvent influence on base stacking.  

PubMed Central

In this paper we present a detailed analysis of the base-stacking phenomenon in different solvents, using nanosecond molecular dynamics simulations. The investigation focuses on deoxyribo- and ribodinucleoside monophosphates in aqueous and organic solutions. Organic solvents with a low dielectric constant, such as chloroform, and solvents with intermediate dielectric constants, such as dimethyl sulfoxide and methanol, were analyzed. This was also done for water, which is highly polar and has a high dielectric constant. Structural parameters such as the sugar puckering and the base-versus-base orientations, as well as the energetics of the solute-solvent interactions, were examined in the different solvents. The obtained data demonstrate that base stacking is favored in the high dielectric aqueous solution, followed by methanol and dimethyl sulfoxide with intermediate dielectric constants, and chloroform, with a low dielectric constant.

Norberg, J; Nilsson, L

1998-01-01

226

Stacked CMOS SRAM cell  

NASA Astrophysics Data System (ADS)

A static random access memory (SRAM) cell with cross-coupled stacked CMOS inverters is demonstrated for the first time. In this approach, CMOS inverters are fabricated with a laser recrystallized p-channel device stacked on top of and sharing the gate with a bulk n-channel device using a modified two-polysilicon n-MOS process. The memory cell has been exercised through the write and read cycles with external signal generators while the output is buffered by an on-chip, stacked-CMOS-inverter-based amplifier.

Chen, C.-E.; Lam, H. W.; Malhi, S. D. S.; Pinizzotto, R. F.

1983-08-01

227

High order stacking of a perfluoro ‘Y-enyne’  

Microsoft Academic Search

The X-ray structure of perfluorophenyl substituted Y-enyne 1 reveals a face-to-face stacking interaction between phenyl and perfluorophenyl groups of different molecules resulting in a high order in the solid state. Acetylene–arene and acetylene–fluorine interactions also contribute to the high order stacking. The X-ray structure suggests a distorted conjugation of the chromophore.

Bilal R Kaafarani; A. Alan Pinkerton; Douglas C Neckers

2001-01-01

228

Intramolecular stacking interactions in ternary copper(II) complexes formed by a heteroaromatic amine and 9-[2-(2-phosphonoethoxy)ethyl]adenine, a relative of the antiviral nucleotide analogue 9-[2-(phosphonomethoxy)ethyl]adenine.  

PubMed

The stability constants of the mixed-ligand complexes formed between Cu(Arm)2+, where Arm=2,2'-bipyridine (Bpy) or 1,10-phenanthroline (Phen), and the dianions of 9-[2-(2-phosphonoethoxy)ethyl]adenine (PEEA2-) and (2-phosphonoethoxy)ethane (PEE2-), also known as [2-(2-ethoxy)ethyl]phosphonate, were determined by potentiometric pH titrations in aqueous solution (25 degrees C; I=0.1 M, NaNO3). The ternary Cu(Arm)(PEEA) complexes are considerably more stable than the corresponding Cu(Arm)(R-PO3) species, where R-PO3(2-) represents a phosph(on)ate ligand with a group R that is unable to participate in any kind of interaction within the complexes. The increased stability is attributed to intramolecular stack formation in the Cu(Arm)(PEEA) complexes and also, to a smaller extent, to the formation of 6-membered chelates involving the ether oxygen atom present in the -CH2-O-CH2-CH2-PO3(2-) residue of PEEA2-. This latter interaction is separately quantified by studying the ternary Cu(Arm)(PEE) complexes which can form the 6-membered chelates but where no intramolecular ligand-ligand stacking is possible. Application of these results allows a quantitative analysis of the intramolecular equilibria involving three structurally different Cu(Arm)(PEEA) species; e.g., of the Cu(Bpy)(PEEA) system about 11% exist with the metal ion solely coordinated to the phosphonate group, 4% as a 6-membered chelate involving the ether oxygen atom of the -CH2-O-CH2CH2-PO3(2-) residue, and 85% with an intramolecular stack between the adenine moiety of PEEA2- and the aromatic rings of Bpy. In addition, the Cu(Arm)(PEEA) complexes may be protonated, leading to Cu(Arm)(H;PEEA)+ species for which it is concluded that the proton is located at the phosphonate group and that the complexes are mainly formed (50 and 70%) by a stacking adduct between Cu(Arm)2+ and the adenine residue of H(PEEA)-. Finally, the stacking properties of adenosine 5'-monophosphate (AMP2-), of the dianion of 9-[2-(phophonomethoxy)ethyl]adenine (PMEA2-) and of several of its analogues (=PA2-) are compared in their ternary Cu(Arm)(AMP) and Cu(Arm)(PA) systems. Conclusions regarding the antiviral properties of several acyclic nucleoside phosphonates are shortly discussed. PMID:15541501

Fernández-Botello, Alfonso; Holý, Antonín; Moreno, Virtudes; Sigel, Helmut

2004-12-01

229

(E)-3-{4-[(7-Chloroquinolin-4-yl)oxy]-3-methoxyphenyl}-1-(4-methylphenyl)prop-2-en-1-one: a ladder-like structure resulting solely from ?-? stacking interactions.  

PubMed

In the title compound, C26H20ClNO3, the quinoline fragment is nearly orthogonal to the adjacent aryl ring, while the rest of the molecular skeleton is close to being planar. The crystal structure contains no hydrogen bonds of any sort, but there are two ?-? stacking interactions present. One, involving the quinoline ring, links molecules related by inversion, while the other, involving the two nonfused aryl rings, links molecules related by translation, so together forming a ladder-type arrangement. PMID:24992110

Montoya, Alba; Insuasty, Braulio; Cobo, Justo; Glidewell, Christopher

2014-07-15

230

Design and synthesis of organic semiconductors with strong noncovalent interactions  

NASA Astrophysics Data System (ADS)

The development of organic molecules as active components of electronic and optoelectronic devices has seen unprecedented progress in the past decade. This attention is primarily due to the potential impact on large-area and low-cost fabrication of devices, integrated circuits, flexible displays, and in particular, organic field-effect transistors (OFETs). Organic semiconductors that pack face-to-face in the solid state are of particular interest since they are known to self-assemble into 1-D nanostructures due to strong pi-pi interactions. Engineering linear/planar molecules to pack face-to-face is challenging because the interacting forces between organic molecules are relatively weak. Three approaches were used to induce face-to-face packing in organic semiconductors: (1) several derivatives of hexaazatrinaphthylene, (HATNA), were designed which vary in their degree of hydrogen bonding, rigidity, and electron deficiency. Hydrogen bonded moieties induced strong interaction between cores that formed robust nanowires when subjected to nonpolar solvents. While no device data was measured for these materials, substituents location was found to have a profound effect on the electronic properties; (2) Inspired by S···S interactions found in tetrathiafulvalene (TTF) and electrostatic interactions found in 1,2,5-thiadiazole derivatives, a hybrid of these two molecules was developed (BT-TTF-1). Short intermolecular S···S, S···N, and S···C contacts define the solid state structure of BT-TTF-1 single crystals which pi-stack along the [100]. Theoretical insight into the nature of the interactions revealed that the close contacts are electrostatic in origin rather than the result of London dispersion forces. Thermal evaporation yields a network of poorly connected crystals which significantly limits the mobility. Solvent-cast single-crystal nanowire transistors showed mobilities as large as 0.36 cm2/Vs with excellent device characteristics underscoring the applicability of solvent-dispersed crystals for high-performance transistor devices; (3) 1,2,5-thiadiazole modified linear acenes, which varied in polarizable heteroatoms in the fused ring system were designed and synthesized. Short thiadiazole contacts were also observed in these molecules and though energy levels were similar, only linear diazaacenes showed reduction potentials in an electrochemical cell.

Tucker, Neil Maxwell

231

Nature and Magnitude of Aromatic Stacking of Nucleic Acid Bases  

SciTech Connect

This review summarises recent advances in quantum chemical calculations of base-stacking forces in nucleic acids. We explain in detail the very complex relationship between the gas-phase basestacking energies, as revealed by quantum chemical (QM) calculations, and the highly variable roles of these interactions in nucleic acids. This issue is rarely discussed in quantum chemical and physical chemistry literature. We further extensively discuss methods that are available for basestacking studies, complexity of comparison of stacking calculations with gas phase experiments, balance of forces in stacked complexes of nucleic acid bases, and the relation between QM and force field descriptions. We also review all recent calculations on base-stacking systems, including details analysis of the B-DNA stacking. Specific attention is paid to the highest accuracy QM calculations, to the decomposition of the interactions, and development of dispersion-balanced DFT methods. Future prospects of computational studies of base stacking are discussed.

Sponer, Jiri; Riley, Kevin E.; Hobza, Pavel

2008-04-07

232

Observation of pi+pi-pi+pi- photoproduction in ultraperipheral heavy-ion collisions at sqrt sNN = 200 GeV at the STAR detector  

SciTech Connect

We present a measurement of {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} photonuclear production in ultra-peripheral Au-Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} final states are observed at low transverse momentum and are accompanied by mutual nuclear excitation of the beam particles. The strong enhancement of the production cross section at low transverse momentum is consistent with coherent photoproduction. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} invariant mass spectrum of the coherent events exhibits a broad peak around 1540 {+-} 40 MeV/c{sup 2} with a width of 570 {+-} 60 MeV/c{sup 2}, in agreement with the photoproduction data for the {rho}{sup 0}(1700). We do not observe a corresponding peak in the {pi}{sup +}{pi}{sup -} final state and measure an upper limit for the ratio of the branching fractions of the {rho}{sup 0}(1700) to {pi}{sup +}{pi}{sup -} and {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} of 2.5% at 90% confidence level. The ratio of {rho}{sup 0}(1700) and {rho}{sup 0}(770) coherent production cross sections is measured to be 13.4 {+-} 0.8{sub stat.} {+-} 4.4{sub syst.}%.

STAR Collaboration; Abelev, Betty

2010-07-05

233

Barrier RF stacking  

SciTech Connect

A novel wideband RF system, nicknamed the barrier RF, has been designed, fabricated and installed in the Fermilab Main Injector. The cavity is made of seven Finemet cores, and the modulator made of two bipolar high-voltage fast solid-state switches. The system can deliver {+-}7 kV square pulses at 90 kHz. The main application is to stack two proton batches injected from the Booster and squeeze them into the size of one so that the bunch intensity can be doubled. High intensity beams have been successfully stacked and accelerated to 120 GeV with small losses. The problem of large longitudinal emittance growth is the focus of the present study. An upgraded system with two barrier RF cavities for continuous stacking is under construction. This work is part of the US-Japan collaborative agreement.

Chou, W.; Wildman, D.; /Fermilab; Zheng, H.; /Caltech; Takagi, A.; /KEK, Tsukuba

2004-12-01

234

Laser pulse stacking method  

DOEpatents

A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter. 2 figs.

Moses, E.I.

1992-12-01

235

Importance of ?-Stacking Interactions in the Hydrogen Atom Transfer Reactions from Activated Phenols to Short-Lived N-Oxyl Radicals.  

PubMed

A kinetic study of the hydrogen atom transfer from activated phenols (2,6-dimethyl- and 2,6-di-tert-butyl-4-substituted phenols, 2,2,5,7,8-pentamethylchroman-6-ol, caffeic acid, and (+)-cathechin) to a series of N-oxyl radical (4-substituted phthalimide-N-oxyl radicals (4-X-PINO), 6-substituted benzotriazole-N-oxyl radicals (6-Y-BTNO), 3-quinazolin-4-one-N-oxyl radical (QONO), and 3-benzotriazin-4-one-N-oxyl radical (BONO)), was carried out by laser flash photolysis in CH3CN. A significant effect of the N-oxyl radical structure on the hydrogen transfer rate constants (kH) was observed with kH values that monotonically increase with increasing NO-H bond dissociation energy (BDENO-H) of the N-hydroxylamines. The analysis of the kinetic data coupled to the results of theoretical calculations indicates that these reactions proceed by a hydrogen atom transfer (HAT) mechanism where the N-oxyl radical and the phenolic aromatic rings adopt a ?-stacked arrangement. Theoretical calculations also showed pronounced structural effects of the N-oxyl radicals on the charge transfer occurring in the ?-stacked conformation. Comparison of the kH values measured in this study with those previously reported for hydrogen atom transfer to the cumylperoxyl radical indicates that 6-CH3-BTNO is the best N-oxyl radical to be used as a model for evaluating the radical scavenging ability of phenolic antioxidants. PMID:24784172

Mazzonna, Marco; Bietti, Massimo; DiLabio, Gino A; Lanzalunga, Osvaldo; Salamone, Michela

2014-06-01

236

STACK GAS REHEAT EVALUATION  

EPA Science Inventory

The report gives results of technical and economic evaluations of stack gas reheat (SGR) following wet flue gas desulfurization (FGD) for coal-fired power plants. The evaluations were based on information from literature and a survey of FGD users, vendors, and architect/engineer ...

237

Stacking up the Atmosphere  

NSDL National Science Digital Library

In this hands-on activity, participants learn the characteristics of the five layers of the atmosphere and make illustrations to represent them. They roll the drawings and place them in clear plastic cylinders, and then stack the cylinders to make a model column of the atmosphere.

Youngman, Betsy; Pennycook, Jean; Huffman, Louise; Dahlman, Luann; Nebraska, Andrill- U.

238

Stacking and Hydrogen Bonding. DNA Cooperativity at Melting  

Microsoft Academic Search

By taking into account base-base stacking interactions we improve the Generalized Model of Polypeptide Chain (GMPC). Based on a one-dimensional Potts-like model with many-particle interactions, the GMPC describes the helix-coil transition in both polypeptides and polynucleotides. In the framework of the GMPC we show that correctly introduced nearest-neighbor stacking interactions against the background of hydrogen bonding lead to increased stability

Vladimir F. Morozov; Artem V. Badasyan; Arsen V. Grigoryan; Mihran A. Sahakyan; Evgeni Sh. Mamasakhlisov

2004-01-01

239

Coherent emission of light using stacked gratings  

NASA Astrophysics Data System (ADS)

The possibility of temporally and spatially coherent thermal emission has been demonstrated utilizing stacked gratings. We demonstrate that the metallic grating with narrow air slit behaves like a homogeneous slab with large permittivity and small permeability and find that the interaction between the metallic grating and the Bragg grating gives rise to impendence matching at wavelengths located in the photonic band gap of the Bragg grating, which enables the stacked gratings to perform high emission with ultranarrow spectrum and antenna-like spatial response. This paves the way towards the design of a novel infrared source platform for applications such as thermal analysis, imaging, security, biosensing, and medical diagnoses.

Gong, Yongkang; Liu, Xianliang; Li, Kang; Huang, Jungang; Martinez, J. J.; Rees-Whippey, Daniel; Carver, Sara; Wang, Leiran; Zhang, Wenfu; Duan, Tao; Copner, Nigel

2013-05-01

240

Energy Expenditure of Sport Stacking  

ERIC Educational Resources Information Center

Sport stacking is an activity taught in many physical education programs. The activity, although very popular, has been studied minimally, and the energy expenditure for sport stacking is unknown. Therefore, the purposes of this study were to determine the energy expenditure of sport stacking in elementary school children and to compare that value…

Murray, Steven R.; Udermann, Brian E.; Reineke, David M.; Battista, Rebecca A.

2009-01-01

241

VLSI architecture for stack filters  

Microsoft Academic Search

A new approach to implementation of stack filtering has been suggested in the work of Astola et al. (see Proceedings of Int. Conf. on Digital Signal Processing, Limassol, Cyprus, 1995). Based on this approach, efficient algorithms and a new VLSI architecture are developed. They are fast and programmable, thus supporting adaptive stack filtering in real time. An arbitrary stack filter

D. Gevorkian; M. Hu; O. Vainio; J. Astola

1997-01-01

242

An atomic force microcopy study of the mechanical and electricalproperties of monolayer films of molecules with aromatic end groups  

SciTech Connect

The effect of intermolecular {pi}-{pi} stacking on the electrical and mechanical properties of monolayer films molecules containing aromatic groups was studied using atomic force microscopy. Two types of aromatic molecules, (4-mercaptophenyl) anthrylacetylene (MPAA) and (4-mercaptophenyl)-phenylacetylene (MPPA) were used as model systems with different {pi}-{pi} stacking strength. Monolayer films of these molecules on Au(111) surfaces exhibited conductivities differing by more than one order of magnitude, MPAA being the most conductive and MPPA the least conductive. The response to compressive loads by the AFM tip was also found to be very different for both molecules. In MPAA films distinct molecular conductivity changes are observed upon mechanical perturbation. This effect however was not observed on the MPPA film, where intermolecular {pi}-{pi} interactions are likely weaker.

Fang, Liang; Park, J.Y.; Ma, H.; Jen, A.K.-Y.; Salmeron, M.

2007-09-06

243

Stacking and hydrogen bonding: DNA cooperativity at melting.  

PubMed

By taking into account base-base stacking interactions we improve the Generalized Model of Polypeptide Chain (GMPC). Based on a one-dimensional Potts-like model with many-particle interactions, the GMPC describes the helix-coil transition in both polypeptides and polynucleotides. In the framework of the GMPC we show that correctly introduced nearest-neighbor stacking interactions against the background of hydrogen bonding lead to increased stability (melting temperature) and, unexpectedly, to decreased cooperativity (maximal correlation length). The increase in stability is explained as due to an additional stabilizing interaction (stacking) and the surprising decrease in cooperativity is seen as a result of mixing of contributions of hydrogen bonding and stacking. PMID:15468063

Morozov, Vladimir F; Badasyan, Artem V; Grigoryan, Arsen V; Sahakyan, Mihran A; Mamasakhlisov, Yevgeni Sh

2004-12-01

244

Dalitz Plot Analysis of B- -> D+ pi- pi-  

SciTech Connect

The author reports on a Dalitz plot analysis of B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -} decays, based on a sample of about 383 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They find the total branching fraction of the three-body decay: {Beta}(B{sup -} {yields} D{sup +} {pi}{sup -}{pi}{sup -}) = (1.08 {+-} 0.01 {+-} 0.05) x 10{sup -3}. the masses and widths of D*{sub 2}{sup 0} and D*{sub 0}{sup 0}, the 2{sup +} and 0{sup +} c{bar u} P-wave states decaying to D{sup +}{pi}{sup -}, are measured: m{sub D*{sub 2}{sup 0}} = (2460.4 {+-} 1.2 {+-} 1.2 {+-} 1.9) MeV/c{sup 2}, {Lambda}{sub D*{sub 2}{sup 0}} = (41.8 {+-} 2.5 {+-} 2.1 {+-} 2.0) MeV, m{sub D*{sub 0}{sup 0}} = (2297 {+-} 8 {+-} 5 {+-} 19) MeV/c{sup 2} and {Lambda}{sub D*{sub 0}{sup 0}} = (273 {+-} 12 {+-} 17 {+-} 45) MeV. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.

Aubert, : B.

2009-01-29

245

On the dispersion theory of {pi}{pi} scattering  

SciTech Connect

Recent developments in low energy pion physics are reviewed, emphasizing the strength of dispersion theory in this context. As an illustration of the method, I discuss some consequences of the forward dispersion relation obeyed by the isoscalar component of the scattering amplitude.

Leutwyler, H. [Institute for Theoretical Physics, University of Bern, Sidlerstr. 5, CH-3012 (Switzerland)

2007-02-27

246

Measurement of the Ratios of Branching Fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) and B(Bs -> Ds pi) / B(Bd -> Dd pi)  

SciTech Connect

Using 355 pb{sup -1} of data collected by the CDF II detector in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron, they study the fully reconstructed hadronic decays B{sub (s)}{sup 0} {yields} D{sub (s)}{sup -}{pi}{sup +} and B{sub (s)}{sup 0} {yields} D{sub (s)}{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}. They present the first measurement of the ratio of branching fractions {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(B{sup 0} {yields} D{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}) = 1.05 {+-} 0.10(stat.) {+-} 0.22(syst.). They also update their measurement of {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +})/{Beta}(B{sup 0} {yields} D{sup -} {pi}{sup +}) to 1.13 {+-} 0.08(stat.) {+-} 0.23(syst.) improving the statistical uncertainty by more than a factor of two. They find {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}) = [3.8 {+-} 0.3(stat.) {+-} 1.3(syst.)] x 10{sup -3} and {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}) = [8.4 {+-} 0.8(stat.) {+-} 3.2(syst.)] x 10{sup -3}.

Abulencia, A.; /Illinois U., Urbana; Adelman, J.; /Chicago U.; Affolder, T.; /UC, Santa Barbara; Akimoto, T.; /Tsukuba U.; Albrow, M.G.; /Fermilab; Ambrose, D.; /Fermilab; Amerio, S.; /Padua U.; Amidei, D.; /Michigan U.; Anastassov, A.; /Rutgers U., Piscataway; Anikeev, K.; /Fermilab; Annovi, A.; /Frascati /Taiwan, Inst. Phys.

2006-10-01

247

Rho Meson Decay into pi+pi- on Asymmetrical Lattices  

NASA Astrophysics Data System (ADS)

The computation of the lowest-lying hadron masses was the earliest success of lattice QCD. Current spectroscopy is faced with the task of computing excited-states. This is particularly challenging when excited-states appear as scattering resonances. In this case, the resonance parameters have to be determined by studying the energies of the scattering states. Currently it is only computationally feasible to compute resonances of the simplest systems. In our work, we carry out a calculation of the ?(770) resonance seen in the isospin l = 1 two-pion system in the l = 1 channel. To determine the resonance parameters, we compute the scattering phase shifts from the two-pion spectrum using Luscher's formula. Unlike other studies which employ the moving frame formalism, we use lattices with one spatial direction elongated. To vary the momentum of the two-pion state, we adjust the length of the elongated direction. With this approach, the two-pion momentum can be tuned more finely, which allows one to map out the resonance more accurately. In this work, we employed nHYP-smeared clover fermions with two mass-degenerate quarks. The lattice computations were carried out on large elongated lattices with spatial volumes ? 33 fm3. We carried out an exploratory quenched study and found the two-pion spectrum to be compatible with the results obtained using dynamical fermions. Our results showed a disagreement with the physical decay at the level of 20% which is typical for quenched simulations. After completing the quenched study, we recomputed the resonance parameters on fully dynamical gauge configurations with a pion mass of 304(2) MeV. We found a value m? = 827(3)(5) MeV and g??? = 6.67(42) for the resonance mass and coupling constant. Our results are consistent with other lattice studies at similar pion masses and are in good agreement with the prediction from unitarized Chiral Perturbation Theory at NLO. The scattering phase shifts we computed are more evenly distributed throughout the resonance than other studies, and the uncertainty in our measurements is equal to or better than current lattice results at similar pion masses.

Pelissier, Craig S.

248

Barrier RF stacking  

SciTech Connect

This paper introduces a new method for stacking beams in the longitudinal phase space. It uses RF barriers to confine and compress beams in an accelerator, provided that the machine momentum acceptance is a few times larger than the momentum spread of the injected beam. This is the case for the Fermilab Main Injector. A barrier RF system employing Finemet cores and high-voltage solid-state switches is under construction. The goal is to double the number of protons per cycle on the production target for Run2 and NuMI experiments.

Weiren Chou and Akira Takagi

2003-02-24

249

MP2 and CCSD(T) study on hydrogen bonding, aromatic stacking and nonaromatic stacking  

NASA Astrophysics Data System (ADS)

Three groups of molecular clusters were studied using the coupled cluster method with non-iterative triple excitations (CCSD(T)) and the second-order Møller-Plesset perturbational method (MP2): H-bonded DNA base pairs ((cytosine) 2, (isocytosine) 2 and (uracil) 2), aromatic stacked complexes ((pyrrol) 2, (pyrimidine) 2, (triazine) 2, (aminotriazine) 2, (4-aminopyrimidine) 2 and (1-aminopyrimidine) 2) and cyclic H-bonded and stacked (formamide) 2 and (formamidine) 2 dimers. The higher-order correlation energy contributions are repulsive in all aromatic stacked clusters, while for all other systems the CCSD(T) and MP2 methods provide nearly identical results. The interaction energies of stacked complexes converge with the size of basis set much faster than the interaction energies of H-bonded clusters. It follows from the present data that the stacking energies of nucleic acid base pairs, evaluated at the MP2 level with diffuse-polarized medium-sized basis sets should be close to the actual values. The stabilization of H-bonded base pairs evaluated at the same level of theory is expected to be underestimated.

Šponer, J.; Hobza, P.

1997-03-01

250

Stacking with dual bootstrap resampling  

NASA Astrophysics Data System (ADS)

A new kind of stacking scheme, based on the hypothesis testing of signal significance and coherence, is proposed. The significance of stacked data is evaluated by running two kinds of bootstrap resampling, one for standard bootstrap and the other for preparing noise stacks by scrambling relative time-shifts between traces. This dual bootstrap procedure allows us to formulate a two-sample problem for signal significance, which is shown to be more reliable than standard bootstrap estimates. The statistics of noise obtained in dual bootstrap resampling is also used when assessing the coherence of data with the empirical distribution function, in which the effect of noise is deconvolved by rescaling. Unlike conventional non-linear stacks such as Nth-root stack and phase-weighted stack, the new stack can recover signals even when the signal-to-noise ratio (S/N) is low, and compared to simple linear stack, the number of traces required for unambiguous signal detection is reduced by up to two orders of magnitude. The new scheme, called dual bootstrap stack, could facilitate a range of geophysical data processing when trying to detect subtle signals by stacking low S/N data.

Korenaga, Jun

2013-12-01

251

Observation of $\\Upsilon(4S) decays to$\\pi^+pi^-\\Upsilon(1S)$ and $\\pi^+pi^-\\Upsilon(1S)$  

SciTech Connect

The authors present the first measurement of {Upsilon}(4S) decays to {pi}{sup +}{pi}{sup -} {Upsilon}(1S) and {pi}{sup +}{pi}{sup -} {Upsilon}(2S) based on a sample of 230 x 10{sup 6} {Upsilon}(4S) mesons collected with the BABAR detector. They measure the product branching fractions {Beta}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S)) x {Beta}({Upsilon}(1S) {yields} {mu}{sup +}{mu}{sup -}) = (2.23 {+-} 0.25{sub stat} {+-} 0.27{sub sys}) x 10{sup -6} and {Beta}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S)) x {Beta}({Upsilon}(2S) {yields} {mu}{sup +}{mu}{sup -}) = (1.69 {+-} 0.26{sub stat} {+-} 0.20{sub sys}) x 10{sup -6}, from which they derive the partial widths {Lambda}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S)) = (1.8 {+-} 0.4) keV and {Lambda}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S)) = (2.7 {+-} 0.8) keV.

Aubert, B.

2006-04-19

252

Search for D0--anti-D0 Mixing in the Decays D0 --> K+ pi- pi+ pi-  

SciTech Connect

We present a search for D{sup 0}-{bar D}{sup 0} mixing in the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} using 230.4 fb{sup -1} of data collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, we measure the time-integrated mixing rate R{sub M} = (0.019{sub -0.015}{sup +0.016}(stat.) {+-} 0.002(syst.))%, and R{sub M} < 0.048% at the 95% confidence level. Using a frequentist method, we estimate that the data are consistent with no mixing at the 4.3% confidence level. We present results both with and without the assumption of CP conservation. By combining the value of R{sub M} from this analysis with that obtained from an analysis of the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}, we find R{sub M} = (0.020{sub -0.010}{sup +0.011})%, where the uncertainty is statistical only. We determine the upper limit R{sub M} < 0.042% at the 95% confidence level, and we find the combined data are consistent with the no-mixing hypothesis at the 2.1% confidence level.

Aubert, B.

2006-09-26

253

Amplitude Analysis of the Decay $D_s^+ \\to \\pi^+ \\pi^- \\pi^+$ in the Experiment E831/FOCUS  

SciTech Connect

We present in this thesis the Dalitz Plot analysis of the D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} decay, with the data of the E831/FOCUS, that took data in 1996 and 1997. The masses and widhts of f{sub 0}(980) and f{sub 0}(1370) are free parametres of the fit on Dalitz Plot, objectiving to study in detail these resonances. After this analysis we present the Spectator Model study on the S wave in this decay. For this study we used the formalism developed by M. Svec [2] for scattering. We present the comparison between the Isobar Model, frequently used in Dalitz Plot analysis, and this formalism.

Schilithz, Anderson Correa; /Rio de Janeiro, CBPF; ,

2005-01-01

254

The Search for Exotic Mesons in gamma p -> pi+pi+pi-n with CLAS at Jefferson Lab  

SciTech Connect

The {pi}{sub 1}(1600), a J{sup PC} = 1{sup {-+}} exotic meson has been observed by experiments using pion beams. Theorists predict that photon beams could produce gluonic hybrid mesons, of which the {pi}{sub 1}(1600) is a candidate, at enhanced levels relative to pion beams. The g12 rungroup at Jefferson Lab's CEBAF Large Acceptance Spectrometer (CLAS) has recently acquired a large photoproduction dataset, using a liquid hydrogen target and tagged photons from a 5.71 GeV electron beam. A partial-wave analysis of 502K {gamma}p {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}n events selected from the g12 dataset has been performed, and preliminary fit results show strong evidence for well-known states such as the a{sub 1}(1260), a{sub 2}(1320), and {pi}{sub 2}(1670). However, we observe no evidence for the production of the {pi}{sub 1}(1600) in either the partial-wave intensities or the relative complex phase between the 1{sup {-+}} and the 2{sup {-+}} (corresponding to the {pi}{sub 2}) partial waves.

Craig Bookwalter

2011-12-01

255

Measurement of CP Violation Parameters with a Dalitz Plot Analysis of B+- to D(pi+pi-pi0)K+-  

SciTech Connect

We report the results of a CP violation analysis of the decay B{sup {+-}} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}}K{sup {+-}}, where D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} indicates a neutral D meson detected in the final state {pi}{sup +}{pi}{sup -}{pi}{sup 0}, excluding K{sub S}{sup 0}{pi}{sup 0}. The analysis makes use of 324 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring. By analyzing the {pi}{sup +}{pi}{sup -}{pi}{sup 0} Dalitz plot distribution and the B{sup {+-}} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} K{sup {+-}} branching fraction and decay rate asymmetry, we calculate parameters related to the phase {gamma} of the CKM unitarity triangle. We also measure the magnitudes and phases of the components of the D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decay amplitude.

Aubert, B.

2007-03-28

256

Asymmetric Flexible Supercapacitor Stack  

NASA Astrophysics Data System (ADS)

Electrical double layer supercapacitor is very significant in the field of electrical energy storage which can be the solution for the current revolution in the electronic devices like mobile phones, camera flashes which needs flexible and miniaturized energy storage device with all non-aqueous components. The multiwalled carbon nanotubes (MWNTs) have been synthesized by catalytic chemical vapor deposition technique over hydrogen decrepitated Mischmetal (Mm) based AB3 alloy hydride. The polymer dispersed MWNTs have been obtained by insitu polymerization and the metal oxide/MWNTs were synthesized by sol-gel method. Morphological characterizations of polymer dispersed MWNTs have been carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM and HRTEM). An assymetric double supercapacitor stack has been fabricated using polymer/MWNTs and metal oxide/MWNTs coated over flexible carbon fabric as electrodes and nafion® membrane as a solid electrolyte. Electrochemical performance of the supercapacitor stack has been investigated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy.

Leela Mohana Reddy, A.; Estaline Amitha, F.; Jafri, Imran; Ramaprabhu, S.

2008-04-01

257

Asymmetric Flexible Supercapacitor Stack  

PubMed Central

Electrical double layer supercapacitor is very significant in the field of electrical energy storage which can be the solution for the current revolution in the electronic devices like mobile phones, camera flashes which needs flexible and miniaturized energy storage device with all non-aqueous components. The multiwalled carbon nanotubes (MWNTs) have been synthesized by catalytic chemical vapor deposition technique over hydrogen decrepitated Mischmetal (Mm) based AB3alloy hydride. The polymer dispersed MWNTs have been obtained by insitu polymerization and the metal oxide/MWNTs were synthesized by sol-gel method. Morphological characterizations of polymer dispersed MWNTs have been carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM and HRTEM). An assymetric double supercapacitor stack has been fabricated using polymer/MWNTs and metal oxide/MWNTs coated over flexible carbon fabric as electrodes and nafion®membrane as a solid electrolyte. Electrochemical performance of the supercapacitor stack has been investigated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy.

2008-01-01

258

Stacked reverberation mapping  

NASA Astrophysics Data System (ADS)

Over the past 20 years reverberation mapping has proved one of the most successful techniques for studying the local (<1 pc) environment of supermassive black holes that drive active galactic nuclei. Key successes of reverberation mapping have been direct black hole mass estimates, the radius-luminosity relation for the H? line and the calibration of single-epoch mass estimators commonly employed up to z ˜ 7. However, observing constraints mean that few studies have been successful at z > 0.1, or for the more-luminous quasars that make up the majority of current spectroscopic samples, or for rest-frame ultraviolet emission lines available in optical spectra of z > 0.5 objects. Previously, we described a technique for stacking cross-correlations to obtain reverberation mapping results at high z. Here, we present the first results from a campaign designed for this purpose. We construct stacked cross-correlation functions for the C IV and Mg II lines and find a clear peak in both. We find that the peak in the Mg II correlation is at longer lags than C IV consistent with previous results at low redshift. For the C IV sample, we are able to bin by luminosity and find evidence for increasing lags for more-luminous objects. This C IV radius-luminosity relation is consistent with previous studies but with a fraction of the observational cost.

Fine, S.; Shanks, T.; Green, P.; Kelly, B. C.; Croom, S. M.; Webster, R. L.; Berger, E.; Chornock, R.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Price, P. A.

2013-07-01

259

IAS Stacking Library in IDL  

NASA Astrophysics Data System (ADS)

This IDL library is designed to be used on astronomical images. Its main aim is to stack data to allow a statistical detection of faint signal, using a prior. For instance, you can stack 160um data using the positions of galaxies detected at 24um or 3.6um, or use WMAP sources to stack Planck data. It can estimate error bars using bootstrap, and it can perform photometry (aperture photometry, or PSF fitting, or other that you can plug). The IAS Stacking Library works with gnomonic projections (RA---TAN), and also with HEALPIX projection.

Bavouzet, Nicolas; Beelen, Alexandre; Bethermin, Matthieu; Dole, Herve; Ponthieu, Nicolas

2013-02-01

260

Stacked insulator induction accelerator gaps  

SciTech Connect

Stacked insulators, with alternating layers of insulating material and conducting film, have been shown to support high surface electrical field stresses. We have investigated the application of the stacked insulator technology to the design of induction accelerator modules for the Relativistic-Klystron Two-Beam Accelerator program. The rf properties of the accelerating gaps using stacked insulators, particularly the impedance at frequencies above the beam pipe cutoff frequency, are investigated. Low impedance is critical for Relativistic-Klystron Two-Beam Accelerator applications where a high current, bunched beam is trsnsported through many accelerating gaps. An induction accelerator module designs using a stacked insulator is presented.

Houck, T.I.; Westenskow, G.A.; Kim, J.S.; Eylon, S.; Henestroza, E.; Yu, S.S.; Vanecek, D.

1997-05-01

261

Preparation and Characterization of [pi]-Stacking Quinodimethane Oligothiophenes. Predicting Semiconductor Behavior and Bandwidths from Crystal Structures and Molecular Orbital Calculations  

SciTech Connect

A series of new quinodimethane-substituted terthiophene and quaterthiophene oligomers has been investigated for comparison with a previously studied quinoid oligothiophene that has demonstrated high mobilities and ambipolar transport behavior in thin-film transistor devices. Each new quinoidal thiophene derivative shows a reversible one-electron oxidation between 0.85 and 1.32 V, a quasi-reversible one-electron second oxidation between 1.37 and 1.96 V, and a reversible two-electron reduction between -0.05 and -0.23 V. The solution UV-vis-NIR spectrum of each compound is dominated by an intense epsilon congruent with 100,000 M{sup -1} cm{sup -1} low energy pi-pi transition that has a lambda(max) ranging between 648 and 790 nm. All X-ray crystal structures exhibit very planar quinoidal backbones and short intermolecular pi-stacking distances (3.335-3.492 A). Structures exhibit a single pi-stacking distance with parallel cofacial stacking (sulfur atoms of equivalent rings pointed in the same direction) or with alternating distances and antiparallel cofacial stacking (sulfur atoms of equivalent rings pointed in the opposite direction). Examples of the layered and herringbone-packing motifs are observed for both the parallel and the antiparallel cofacial stacking. Analysis of the X-ray structures and molecular orbital calculations indicates that all of these compounds have one-dimensional electronic band structures as a result of the pi-stacking. For structures with a unique pi-stacking distance, a simple geometric overlap parameter calculated from the shape of the molecule and the slip from perfect registry in the pi-stack correlates well with the transfer integrals (t) calculated using molecular orbital theory. The calculated valence (633 meV) and conduction (834 meV) bandwidths for a quinoid quaterthiophene structure are similar to those calculated for the benchmark pentacene and indicate that both hole and electron mobilities could be significant.

Janzen, Daron E.; Burand, Michael W.; Ewbank, Paul C.; Pappenfus, Ted M.; Higuchi, Hiroyuki; da Silva, Demetrio A.; Young, Victor G.; Bredas, Jean-Luc; Mann, Kent R. (GIT); (Minnesota); (Toyama)

2010-11-16

262

The role of intermolecular interactions in the assemblies of Fe{sup II} and Co{sup II} tetrakis-isothiocyanatometalates with tris(1,10-phenanthroline)-Ru{sup II}: Crystal structures of two dual-metal assemblies featuring octahedral cationic and tetrahedral anionic modules  

SciTech Connect

Two new dual-metal assemblies: 2[Ru(phen){sub 3}]{sup 2+}.[Fe(SCN){sub 4}]{sup 2-}.2SCN{sup -}.4H{sub 2}O 1 and [Ru(phen){sub 3}]{sup 2+}.[Co(SCN){sub 4}]{sup 2-}2, (phen:1,10-phenanthroline), have been prepared and their structures were characterized by X-ray diffraction. In 1, the cationic octahedral enantiomers are arranged with a {lambda}{delta}{lambda}{delta}{lambda} sequence supported by {pi}-{pi} stacking and the anionic inorganic tetrahedral units are oriented between these stacks by interacting with the nearby water molecules through strong O-H...O and O-H...S hydrogen bonds. In 2, homochiral double helices in the b-direction are revealed, with tetrakis-isothiocyanate Co{sup II} anions arranged in the crystal to furnish one-dimensional (1D)-helical chains with S...S intermolecular interactions at 3.512(2) and 3.966(2) A supporting [Ru(phen){sub 3}]{sup 2+}{lambda}- and {delta}-helices with Ru...Ru shortest distance of 8.676(7) A. In both 1 and 2, the supramolecular assembly is maintained by C-H...S hydrogen bonds extending between the phenanthroline aromatic carbons in the cationic nodes and the sulphur atoms of the isothiocyanates anions. Analysis of S...S interactions in isothiocyanate containing compounds using Cambridge structural database (CSD) showed an angle dependence categorizing these interactions into 'type-I' and 'type-II'. - Graphical abstract: Side projection in 2 showing the crankshaft caused by S...S interactions in [Co(NCS){sub 4}]{sup 2-} in-between [Ru{sup II}(phen){sub 3}]{sup 2+} helices. Only isothiocyanates arms of [Co(NCS){sub 4}]{sup 2-} that are part of S...S interactions are shown and [Ru{sup II}(phen){sub 3}]{sup 2+} are presented as polyhedra.

Ghazzali, Mohamed [Department of Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Goeteborg (Sweden)], E-mail: mghazz@chalmers.se; Langer, Vratislav; Ohrstroem, Lars [Department of Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Goeteborg (Sweden)

2008-09-15

263

Structural Consequences of Anionic Host-Cationic Guest Interactions in a Supramolecular Assembly  

SciTech Connect

The molecular structure of the self-assembled supramolecular assembly [M{sub 4}L{sub 6}]{sup 12-} has been explored with different metals (M = Ga{sup III}, Fe{sup III}, Ti{sup IV}) and different encapsulated guests (NEt{sub 4}{sup +}, BnNMe{sub 3}{sup +}, Cp{sub 2}Co{sup +}, Cp*{sub 2}Co{sup +}) by X-ray crystallography. While the identity of the metal ions at the vertices of the M{sub 4}L{sub 6} structure is found to have little effect on the assembly structure, encapsulated guests significantly distort the size and shape of the interior cavity of the assembly. Cations on the exterior of the assembly are found to interact with the assembly through either {pi}-{pi}, cation-{pi}, or CH-{pi} interactions. In some cases, the exterior guests interact with only one assembly, but cations with the ability to form multiple {pi}-{pi} interactions are able to interact with adjacent assemblies in the crystal lattice. The solvent accessible cavity of the assembly is modeled using the rolling probe method and found to range from 253-434 {angstrom}{sup 3}, depending on the encapsulated guest. Based on the volume of the guest and the volume of the cavity, the packing coefficient for each host-guest complex is found to range from 0.47-0.67.

Pluth, Michael D.; Johnson, Darren W.; Szigethy, Geza; Davis, Anna V.; Teat, Simon J.; Oliver, Allen G.; Bergman, Robert G.; Raymond, Kenneth N.

2008-07-09

264

In-stack virtual impactor  

SciTech Connect

In-stack virtual impactor described is a unique instrument that can provide real-time continuous measurements of stack aerosol particle-size distributions and can simultaneously provide size-segregated samples for morphological or chemical analysis. 2 references, 12 figures, 1 table.

Woffinden, G.J.; Downs, J.L.; Markowski, G.R.; Fegley, M.J.

1982-02-01

265

Spherical torus center stack design  

SciTech Connect

The low aspect ratio spherical torus (ST) configuration requires that the center stack design be optimized within a limited available space, using materials within their established allowables. This paper presents certer stack design methods developed by the National Spherical Torus Experiment (NSTX) Project Team during the initial design of NSTX, and more recently for studies of a possible next step ST (NSST) device.

Neumeyer, C. L. [Princeton Plasma Physics Laboratory (PPPL); Peng, Yueng Kay Martin [ORNL

2002-01-01

266

Spherical Torus Center Stack Design  

SciTech Connect

The low aspect ratio spherical torus (ST) configuration requires that the center stack design be optimized within a limited available space, using materials within their established allowables. This paper presents center stack design methods developed by the National Spherical Torus Experiment (NSTX) Project Team during the initial design of NSTX, and more recently for studies of a possible next-step ST (NSST) device.

C. Neumeyer; P. Heitzenroeder; C. Kessel; M. Ono; M. Peng; J. Schmidt; R. Woolley; I. Zatz

2002-01-18

267

Die Stacking (3D) Microarchitecture  

Microsoft Academic Search

D die stacking is an exciting new technology that in- creases transistor density by vertically integrating two or more die with a dense, high-speed interface. The result of 3D die stacking is a significant reduction of interconnect both within a die and across dies in a system. For instance, blocks within a microprocessor can be placed vertically on multiple die

Bryan Black; Murali Annavaram; Ned Brekelbaum; John Devale; Lei Jiang; Gabriel H. Loh; Don McCauley; Pat Morrow; Donald W. Nelson; Daniel Pantuso; Paul Reed; Jeff Rupley; Sadasivan Shankar; John Paul Shen; Clair Webb

2006-01-01

268

The interplay between hydrogen bonding and ?-? stacking interactions in the crystal packing of N1-thyminyl derivatives, and implications for the photo-chemical [2? + 2?]-cycloaddition of thyminyl compounds.  

PubMed

The solid-state photo-chemical dimerisation of thyminyl derivatives occurs when two thyminyl units are aligned in such a way that the olefinic moieties are separated by a distance of less than 4.2 Å. When irradiated with >270 nm UV, the thyminyl olefinic groups undergo [2? + 2?]-cycloaddition to form a dimeric cyclobutane derivative. However, the design and execution of [2? + 2?]-cycloaddition reactions can be challenging due to the requirement to produce molecular crystals with the necessary olefinic alignment. In this investigation, the crystallographic and solid-state photo-chemical reactions of six N1-thyminyl derivatives are studied. Only one derivative, thyminyl propanamide (), was found to undergo [2? + 2?]-cycloaddition in the crystalline state. As such, quantum chemical methods were employed to study the photo-chemical transition states of the derivatives, as well as the strengths of typical intermolecular interactions that were observed in their crystal structures (such as ?-? stacking between the thyminyl rings, Watson and Crick style hydrogen bonding and hydrogen bonding between functional groups of N1 substituents). These results were used to rationalise the solid-state photo-reactivity of more complex bis-thyminyl monomers. PMID:22952024

Johnston, Priscilla; Izgorodina, Ekaterina I; Saito, Kei

2012-12-01

269

Preparation, solid-state characterization, and computational study of a crown ether attached to a squaramide.  

PubMed

[structure: see text] Crystals of a disecondary squaramide covalently linked to a crown ether presents a great variety of inter- and intramolecular nonbonded interactions including C-H/pi contacts, C-H...O and N-H...O hydrogen bonds, and pi-pi stacking between squaramide rings. Latter interaction, the stacking between squaramide rings, can be considered as an experimental evidence for the proposed aromaticity of squaramide when it is forming hydrogen bonds, either as acceptor or donor. PMID:15816721

Frontera, Antonio; Orell, Maria; Garau, Carolina; Quiñonero, David; Molins, Elies; Mata, Ignasi; Morey, Jeroni

2005-04-14

270

From a Single Cell to a Stack Modeling  

Microsoft Academic Search

The aforementioned examples assume that single cells can be stacked together with linear scalability, i.e. if each cell produces\\u000a 1 W ten cells will produce exactly 10 W. This, of course, is not a valid assumption in most cases. In a real stack each cell\\u000a experiences different electrical, thermal and structural constraints due the neighboring cells. The interaction between the

Ismail B. Celik; Suryanarayana R. Pakalapati

271

Noncovalent interactions in supramolecular complexes: a study on corannulene and the double concave buckycatcher.  

PubMed

Stimulated by the recent observation of pi-pi interactions between C60 and corannulene subunits in a molecular tweezer arrangement (J Am Chem Soc 2007, 129, 3842), a density functional theory study was performed to analyze the electronic structure and properties of various noncovalent corannulene complexes. The theoretical approach is first applied to corannulene complexes with a series of benchmark molecules (CH4, NH3, and H2O) using several new-generation density functionals. The performance of nine density functionals, illustrated by computing binding energies of the corannulene complexes, demonstrates that Zhao and Truhlar's MPWB1K and M05-2X functionals provide energies similar to that obtained at the SCS-MP2 level. In contrast, most of the other popular density functionals fail to describe this noncovalent interaction or yield purely repulsive interactions. Further investigations with the M05-2X functional show that the binding energy of C60 with corannulene subunits in the relaxed molecular receptor clip geometry is -20.67 kcal/mol. The results of this calculation further support the experimental interpretation of pure pi-pi interactions between a convex fullerene and the concave surfaces of two corannulene subunits. PMID:18504779

Wong, Bryan M

2009-01-15

272

Stacking boundaries and transport in bilayer graphene.  

PubMed

Pristine bilayer graphene behaves in some instances as an insulator with a transport gap of a few millielectronvolts. This behavior has been interpreted as the result of an intrinsic electronic instability induced by many-body correlations. Intriguingly, however, some samples of similar mobility exhibit good metallic properties with a minimal conductivity of the order of 2e(2)/h. Here, we propose an explanation for this dichotomy, which is unrelated to electron interactions and based instead on the reversible formation of boundaries between stacking domains ("solitons"). We argue, using a numerical analysis, that the hallmark features of the previously inferred many-body insulating state can be explained by scattering on boundaries between domains with different stacking order (AB and BA). We furthermore present experimental evidence, reinforcing our interpretation, of reversible switching between a metallic and an insulating regime in suspended bilayers when subjected to thermal cycling or high current annealing. PMID:24605877

San-Jose, P; Gorbachev, R V; Geim, A K; Novoselov, K S; Guinea, F

2014-04-01

273

Seismic qualification of ventilation stack  

SciTech Connect

This paper describes the method to be used to qualify the 105 K ventilation stack at the U.S. Department of Energy`s Hanford Site, near Richland, Washington, under seismic and wind loadings. The stack stands at 175 ft (53.34 m), with a diameter tapering from 22 ft (6.71 m) at the foundation to 12.83 ft (3.91 m) at the top. Although the stack is classified as Safety Class 3 (low hazard), it is treated as a Safety Class 1 (high hazard) component, as failure could damage a Safety Class 1 facility (the irradiated fuel storage basin). The evaluation used U.S. Department of Energy criteria specified in UCRL 15910 (1990). The seismic responses of the stack under earthquake loading were obtained from modal analyses with response spectrum input that used the ANSYS (1989) finite-element computer code. The moments and shear forces from the results of seismic analysis were used to qualify the reinforcement capacity of the stack structure by the ultimate-strength method. The wind forces acting on the stack in both along-wind and crosswind directions were also calculated. Presented are evaluations of the soil bearing pressure, the moment, and the shear capacity of the stack foundation.

Chen, W.W.; Huang, S.N.; Lindquist, M.R.

1993-10-01

274

[2,5-Bis(2,2'-bipyridyl-6-yl)-3,4-diazahexa-2,4-diene]dichloridomanganese(II): from a mononuclear compound to a three-dimensional supramolecular framework through C-H...Cl hydrogen bonds and ?-? stacking interactions.  

PubMed

The title compound, [MnCl2(C24H20N6)], has been synthesized and characterized based on the multifunctional ligand 2,5-bis(2,2'-bipyridyl-6-yl)-3,4-diazahexa-2,4-diene (L). The Mn(II) centre is five-coordinate with an approximately square-pyramidal geometry. The L ligand acts as a tridendate chelating ligand. The mononuclear molecules are bridged into a one-dimensional chain by two C-H...Cl hydrogen bonds. These chains are assembled into a two-dimensional layer through ?-? stacking interactions between adjacent uncoordinated bipyridyl groups. Furthermore, a three-dimensional supramolecular framework is attained through ?-? stacking interactions between adjacent coordinated bipyridyl groups. PMID:24992119

Lu, Zhengliang; Zhao, Yuanchao; Chen, Baolian; Huang, Ximing; Fan, Chunhua

2014-07-15

275

A Fluidic, Stacked Mail Counter.  

National Technical Information Service (NTIS)

The feasibility of counting vertically stacked letters in standard mail racks with the use of a fluidic sensing and counting system was investigated. A description of the system, the test program conducted, and innovations employed to increase the system ...

C. E. Spyropoulos

1969-01-01

276

RF stacking without emittance dilution  

SciTech Connect

A long-established technique for accumulating high current in a storage ring is to inject additional beam off-momentum and move it into the main beam stack by rf acceleration. This procedure necessarily dilutes the longitudinal phase space density, because the rf perturbs the stack as the new beam approaches closely in momentum. For accumulators that use beam cooling to obtain a high phase space density, this perturbation may result in an unacceptable performance limitation. Using broadband rf to establish and manipulate azimuthal barriers to the motion of the stack and injected beam permits practically dilution-free longitudinal phase space stacking. The concept is described and illustrated with a detailed example which pertains to the Fermilab Recycler ring.

J. A. MacLachlan

2000-06-23

277

Mechanical Stiffening of Porphyrin Nanorings through Supramolecular Columnar Stacking  

PubMed Central

Solvent-induced aggregates of nanoring cyclic polymers may be transferred by electrospray deposition to a surface where they adsorb as three-dimensional columnar stacks. The observed stack height varies from single rings to four stacked rings with a layer spacing of 0.32 ± 0.04 nm as measured using scanning tunneling microscopy. The flexibility of the nanorings results in distortions from a circular shape, and we show, through a comparison with Monte Carlo simulations, that the bending stiffness increases linearly with the stack height. Our results show that noncovalent interactions may be used to control the shape and mechanical properties of artificial macromolecular aggregates offering a new route to solvent-induced control of two-dimensional supramolecular organization.

2013-01-01

278

Processors for generalized stack filters  

Microsoft Academic Search

New processor structures for generalized stack filters are proposed. They can be implemented using different numbers of Boolean function units. The class of pipeline-parallel structures for generalized stack filters is simple and modular in structure, and suitable for VLSI implementation. Coder and decoder networks are developed for the mutual transform of binary-weighted and unary-weighted codes as the thresholding and addition

D. Akopian; O. Vainio; S. Agaian; J. Astola

1995-01-01

279

Full Piezoelectric Multilayer-Stacked Hybrid Actuation/Transduction Systems  

NASA Technical Reports Server (NTRS)

The Stacked HYBATS (Hybrid Actuation/Transduction system) demonstrates significantly enhanced electromechanical performance by using the cooperative contributions of the electromechanical responses of multilayer, stacked negative strain components and positive strain components. Both experimental and theoretical studies indicate that, for Stacked HYBATS, the displacement is over three times that of a same-sized conventional flextensional actuator/transducer. The coupled resonance mode between positive strain and negative strain components of Stacked HYBATS is much stronger than the resonance of a single element actuation only when the effective lengths of the two kinds of elements match each other. Compared with the previously invented hybrid actuation system (HYBAS), the multilayer Stacked HYBATS can be designed to provide high mechanical load capability, low voltage driving, and a highly effective piezoelectric constant. The negative strain component will contract, and the positive strain component will expand in the length directions when an electric field is applied on the device. The interaction between the two elements makes an enhanced motion along the Z direction for Stacked-HYBATS. In order to dominate the dynamic length of Stacked-HYBATS by the negative strain component, the area of the cross-section for the negative strain component will be much larger than the total cross-section areas of the two positive strain components. The transverse strain is negative and longitudinal strain positive in inorganic materials, such as ceramics/single crystals. Different piezoelectric multilayer stack configurations can make a piezoelectric ceramic/single-crystal multilayer stack exhibit negative strain or positive strain at a certain direction without increasing the applied voltage. The difference of this innovation from the HYBAS is that all the elements can be made from one-of-a-kind materials. Stacked HYBATS can provide an extremely effective piezoelectric constant at both resonance and off resonance frequencies. The effective piezoelectric constant can be alternated by varying the size of each component, the degree of the pre-curvature of the positive strain components, the thickness of each layer in the multilayer stacks, and the piezoelectric constant of the material used. Because all of the elements are piezoelectric components, Stacked HYBATS can serve as projector and receiver for underwater detection. The performance of this innovation can be enhanced by improving the piezoelectric properties.

Su, Ji; Jiang, Xiaoning; Zu, Tian-Bing

2011-01-01

280

Fuel cell stack compressive loading system  

DOEpatents

A fuel cell module comprising a stack of fuel cells with reactant gas manifolds sealed against the external surfaces of the stack includes a constraint system for providing a compressive load on the stack wherein the constraint system maintains the stack at a constant height (after thermal expansion) and allows the compressive load to decrease with time as a result of the creep characteristics of the stack. Relative motion between the manifold sealing edges and the stack surface is virtually eliminated by this constraint system; however it can only be used with a stack having considerable resiliency and appropriate thermal expansion and creep characteristics.

Fahle, Ronald W. (Manchester, CT); Reiser, Carl A. (Glastonbury, CT)

1982-01-01

281

Split stack blowout prevention system  

SciTech Connect

A blowout prevention system for an offshore structure positioned on the underwater bottom in a body of water which contains moving ice masses that could force the structure off location wherein a surface blowout preventer stack for conventional well control is connected to the upper end of a riser with the lower end of the riser being disconnectably connected to a subsurface blowout preventer stack which provides the necessary well control should the structure be forced off location. The subsurface stack is positioned on a wellhead located in a chamber in the subsea bottom and is disconnectably connected to the riser so that the riser may be quickly removed from the subsea bottom should the structure be forced off location.

Crager, B.L.; Ray, D.R.; Steddum, R.E.

1980-03-18

282

Stacked generalization and simulated evolution.  

PubMed

A stacked generalization strategy in which an evolutionary algorithm generates baselevel predictive models is described. The evolutionary algorithm incorporates model validation and an inductive ranking criterion which encourages diversity of prediction errors. Higher levels of the stack of generalizers yield predictors that work through memory-based correction and combination of predictions produced by populations of models obtained in lower levels of the stack. The strategy has been applied to the classic problem of predicting annual sunspots activity. Baselevel predictors are drawn from a class of recurrent neural networks. Normalized mean squared errors of 0.064 and 0.19 for the conventional test intervals of 1921-1955 and 1956-1979, respectively, improve upon previously published results. The strategy has also been used to accurately forecast the behaviour of a synthetic system which makes random transitions between two states of low-dimensional chaos. PMID:8735383

English, T M

1996-01-01

283

Mutual coupling of stacked UHF RFID antennas in NFC applications  

Microsoft Academic Search

As RFID deployment moves from pallet level to item level, UHF RFID has gained more and more momentum in NFC (near field communication) applications recently. Similar to HF RFID tags, UHF RFID tags in NFC also use inductive coupling antennas to interact with the readers. However, in item-level deployment, items with UHF RFID tags are often stacked closely and interrogated

Xiaosheng Chen; Feng Lu; Terry T. Ye

2009-01-01

284

Electrodialysis Membrane Stack MS 3070.  

National Technical Information Service (NTIS)

Design, operation and assembly of the electrodialysis membrane stack are described. The main element is a new sealing frame which, when coupled with a suitable net spacer, yields a good flow distribution in the cells and largely prevents internal and exte...

K. Kneifel K. Hattenbach U. Martens

1985-01-01

285

Boiler Stack Gas Heat Recovery.  

National Technical Information Service (NTIS)

This report is a detailed study of various heat recovery schemes for Navy shore facilities to use otherwise lost stack heat. The waste heat can be used alternatively to improve the boiler efficiency through feedwater and/or combustion-air preheating, or t...

P. C. Lu T. T. Fu S. C. Garg G. Nowakowski

1987-01-01

286

Progress Update: Stack Project Complete  

ScienceCinema

Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

287

200 Areas stack gas conference  

Microsoft Academic Search

A meeting was held at 9:30 A.M., January 20, 1949 in the 703 Building Conference Room in order to review the present status and subsequent plans of the 200 Areas stack gas problem with C.E. Lapple of the DuPont Company. Process ventilation air and dissolver off-gases were discussed.

Stainken

1949-01-01

288

STACK SAMPLING FOR ORGANIC EMISSIONS  

EPA Science Inventory

The paper reviews some of the more important principles involved in stack sampling for organics, briefly describes and discusses recently developed equipment, and points out a few of the more serious pitfalls. Extensive references are provided, many of which are often overlooked ...

289

Progress Update: Stack Project Complete  

SciTech Connect

Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

Cody, Tom

2010-01-01

290

POLYMERIC INTERFACES FOR STACK MONITORING  

EPA Science Inventory

Research has been performed on the use of polymeric interfaces for in situ continuous stack monitoring of gaseous pollutants. Permeabilities of candidate interface materials to SO2 were measured at temperatures from ambient to 200C, and the results were used to design interfaces ...

291

Progress Update: Stack Project Complete  

ScienceCinema

Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

Cody, Tom

2012-06-14

292

Modular fuel-cell stack assembly  

DOEpatents

A modular multi-stack fuel-cell assembly in which the fuel-cell stacks are situated within a containment structure and in which a gas distributor is provided in the structure and distributes received fuel and oxidant gases to the stacks and receives exhausted fuel and oxidant gas from the stacks so as to realize a desired gas flow distribution and gas pressure differential through the stacks. The gas distributor is centrally and symmetrically arranged relative to the stacks so that it itself promotes realization of the desired gas flow distribution and pressure differential.

Patel, Pinakin (Danbury, CT) [Danbury, CT; Urko, Willam (West Granby, CT) [West Granby, CT

2008-01-29

293

True-amplitude single-stack redatuming  

NASA Astrophysics Data System (ADS)

Based on the chaining of diffraction-stack migration and isochron-stack demigration, we derive a general true-amplitude Kirchhoff-type single-stack operator for 3D and 2.5D redatuming. It consists of performing a single weighted stack along adequately chosen stacking surfaces or lines. The corresponding traveltimes and weight functions can be calculated using quantities obtained from dynamic ray tracing. The operator simplifies when specified for zero-offset data. For simple types of media, we derive analytic expressions for the stacking lines and weight functions and demonstrate their functionality with numerical examples.

Pila, Matheus F.; Schleicher, Jörg; Novais, Amélia; Coimbra, Tiago A.

2014-06-01

294

Inhibition of neutron irradiation on oxidation stacking faults on the surface of Si wafers  

NASA Astrophysics Data System (ADS)

The generation of stacking faults (SF) during thermal oxidation of Czochralski Si (CZ-Si) were investigated. It has been shown that oxidation-induced stacking faults (OSF) have been retarded seriously in neutron-irradiated Si. Our studies suggest that the inhibition of OSF results from the interaction of neutron-irradiated defects with oxygen in Si.

Li, Yangxian; Ju, Yulin; Liu, Caichi; Xu, Yuesheng; Wang, Hongmei

1996-03-01

295

Nature and magnitude of aromatic base stacking in DNA and RNA: Quantum chemistry, molecular mechanics, and experiment.  

PubMed

Base stacking is a major interaction shaping up and stabilizing nucleic acids. During the last decades, base stacking has been extensively studied by experimental and theoretical methods. Advanced quantum-chemical calculations clarified that base stacking is a common interaction, which in the first approximation can be described as combination of the three most basic contributions to molecular interactions, namely, electrostatic interaction, London dispersion attraction and short-range repulsion. There is not any specific ?-? energy term associated with the delocalized ? electrons of the aromatic rings that cannot be described by the mentioned contributions. The base stacking can be rather reasonably approximated by simple molecular simulation methods based on well-calibrated common force fields although the force fields do not include nonadditivity of stacking, anisotropy of dispersion interactions, and some other effects. However, description of stacking association in condensed phase and understanding of the stacking role in biomolecules remain a difficult problem, as the net base stacking forces always act in a complex and context-specific environment. Moreover, the stacking forces are balanced with many other energy contributions. Differences in definition of stacking in experimental and theoretical studies are explained. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 978-988, 2013. PMID:23784745

Sponer, Ji?í; Sponer, Judit E; Mládek, Arnošt; Jure?ka, Petr; Banáš, Pavel; Otyepka, Michal

2013-12-01

296

Nonlinear wave scattering by stacked layers of semiconductor plasma  

NASA Astrophysics Data System (ADS)

The combinatorial frequency generation by periodic and quasiperiodic stacks of nonlinear semiconductor layers has been studied in the self-consistent problem formulation, taking into account mobility of carriers. The three-wave mixing technique is applied to study the nonlinear processes. It is shown that the mixing processes in passive semiconductor structures are driven by the competitive effects of the collision of charges and resonance interactions of carriers with pump waves. The effects of the pump wave dissipation, layer parameters and stack arrangements on the efficiency of the combinatorial frequency generation are discussed.

Shramkova, Oksana V.

2014-03-01

297

Random stacking sequences in III-V nanowires are correlated  

NASA Astrophysics Data System (ADS)

We investigate crystal plane stacking in InP nanowires with marked wurtzite/zinc-blende phase mixing. We measure the length distributions of hexagonal and cubic segments and the frequencies of all short sequences of monolayers. This reveals spatial correlations extending over several monolayers, which we describe in terms of conditional probabilities. Results can be modeled by considering the energy barriers for nucleation on top of all types of preexisting stacking. A quantitative agreement is obtained only if the interaction with the underlying layers involves the edge energy of the nucleus.

Priante, Giacomo; Harmand, Jean-Christophe; Patriarche, Gilles; Glas, Frank

2014-06-01

298

Glass transition dynamics of stacked thin polymer films.  

PubMed

The glass transition dynamics of stacked thin films of polystyrene and poly(2-chlorostyrene) were investigated using differential scanning calorimetry and dielectric relaxation spectroscopy. The glass transition temperature T(g) of as-stacked thin polystyrene films has a strong depression from that of the bulk samples. However, after annealing at high temperatures above T(g), the stacked thin films exhibit glass transition at a temperature almost equal to the T(g) of the bulk system. The ?-process dynamics of stacked thin films of poly(2-chlorostyrene) show a time evolution from single-thin-film-like dynamics to bulk-like dynamics during the isothermal annealing process. The relaxation rate of the ? process becomes smaller with increase in the annealing time. The time scale for the evolution of the ? dynamics during the annealing process is very long compared with that for the reptation dynamics. At the same time, the temperature dependence of the relaxation time for the ? process changes from Arrhenius-like to Vogel-Fulcher-Tammann dependence with increase of the annealing time. The fragility index increases and the distribution of the ?-relaxation times becomes smaller with increase in the annealing time for isothermal annealing. The observed change in the ? process is discussed with respect to the interfacial interaction between the thin layers of stacked thin polymer films. PMID:22181166

Fukao, Koji; Terasawa, Takehide; Oda, Yuto; Nakamura, Kenji; Tahara, Daisuke

2011-10-01

299

Glass transition dynamics of stacked thin polymer films  

NASA Astrophysics Data System (ADS)

The glass transition dynamics of stacked thin films of polystyrene and poly(2-chlorostyrene) were investigated using differential scanning calorimetry and dielectric relaxation spectroscopy. The glass transition temperature Tg of as-stacked thin polystyrene films has a strong depression from that of the bulk samples. However, after annealing at high temperatures above Tg, the stacked thin films exhibit glass transition at a temperature almost equal to the Tg of the bulk system. The ?-process dynamics of stacked thin films of poly(2-chlorostyrene) show a time evolution from single-thin-film-like dynamics to bulk-like dynamics during the isothermal annealing process. The relaxation rate of the ? process becomes smaller with increase in the annealing time. The time scale for the evolution of the ? dynamics during the annealing process is very long compared with that for the reptation dynamics. At the same time, the temperature dependence of the relaxation time for the ? process changes from Arrhenius-like to Vogel-Fulcher-Tammann dependence with increase of the annealing time. The fragility index increases and the distribution of the ?-relaxation times becomes smaller with increase in the annealing time for isothermal annealing. The observed change in the ? process is discussed with respect to the interfacial interaction between the thin layers of stacked thin polymer films.

Fukao, Koji; Terasawa, Takehide; Oda, Yuto; Nakamura, Kenji; Tahara, Daisuke

2011-10-01

300

Fire extinguishing attachment for chimney stacks  

Microsoft Academic Search

A fire extinguishing attachment including a bracket for mounting on a stove stack and having a tubular guide therethrough. The tubular guide is an elbow tube having an inner end within the stack directed towards the chimney flue and an outer end outside the stack adapted to receive the nozzle of a powder type fire extinguisher. When a chimney fire

Sawtelle

1984-01-01

301

Anomaly Detection Using Call Stack Information  

Microsoft Academic Search

The call stack of a program execution can be a very good information source for intrusion detection. There is no pri or work on dynamically extracting information from call stack and effectively using it to detect exploits. In this paper, w e propose a new method to do anomaly detection using call stack information. The basic idea is to extract

Henry Hanping Feng; Oleg M. Kolesnikov; Prahlad Fogla; Wenke Lee; Weibo Gong

2003-01-01

302

COMMENTS ON STACKING FAULT ENERGY OF THORIUM  

Microsoft Academic Search

Transmission electron microscopic studies were made of foils made from ; cold-rolled thorium sheet. Tangled dislocations forming a crude cell structure ; were observed, but no fringes characteristic of stacking faults were visible. No ; example of cross-slip was observed. The results suggest that thorium has an ; intermediate stacking fault energy. The interpretation of stacking fault ; probability as

J. O. Stiegler; C. J. McHargue

1963-01-01

303

Stacking faults in Si nanocrystals  

SciTech Connect

Si nanocrystals (Si nc) were formed by the implantation of Si{sup +} into a SiO{sub 2} film on (100) Si, followed by high-temperature annealing. High-resolution transmission electron microscopy has been used to examine the microstructure of the Si nc produced by a high-dose (3x10{sup 17} cm{sup -2}) implantation. It is shown that there are only stacking-fault (SF) defects in some nanocrystals; while in others the stacking faults (SFs) coexist with twins. Two kinds of SFs, one being an intrinsic SF, the other being an extrinsic SF, have been observed inside the Si nc. More intrinsic SFs have been found in the Si nc, and the possible reasons are discussed. These microstructural defects are expected to play an important role in the light emission from the Si nc.

Wang, Y.Q.; Smirani, R.; Ross, G.G. [INRS-EMT, 1650, Boulevard Lionel-Boulet, Varennes, Quebec, J3X 1S2 (Canada)

2005-05-30

304

Stacked triangular lattice: Percolation properties  

NASA Astrophysics Data System (ADS)

The stacked triangular lattice has the shape of a triangular prism. In spite of being considered frequently in solid-state physics and materials science, its percolation properties have received little attention. We investigate several nonuniversal percolation properties on this lattice using Monte Carlo simulation. We show that the percolation threshold is pcbond=0.18602±0.00002 for bonds and pcsite=0.26240±0.00005 for sites. The number of clusters at the threshold per site is ncbond=0.28458±0.00005 and ncsite=0.03998±0.00005. The stacked triangular lattice is a convenient choice to study the RGB model [Schrenk , Sci. Rep.10.1038/srep00751 2, 751 (2012)]. We present results on this model and its scaling behavior at the percolation threshold.

Schrenk, K. J.; Araújo, N. A. M.; Herrmann, H. J.

2013-03-01

305

PRECISION COSMOGRAPHY WITH STACKED VOIDS  

SciTech Connect

We present a purely geometrical method for probing the expansion history of the universe from the observation of the shape of stacked voids in spectroscopic redshift surveys. Our method is an Alcock-Paczynski (AP) test based on the average sphericity of voids posited on the local isotropy of the universe. It works by comparing the temporal extent of cosmic voids along the line of sight with their angular, spatial extent. We describe the algorithm that we use to detect and stack voids in redshift shells on the light cone and test it on mock light cones produced from N-body simulations. We establish a robust statistical model for estimating the average stretching of voids in redshift space and quantify the contamination by peculiar velocities. Finally, assuming that the void statistics that we derive from N-body simulations is preserved when considering galaxy surveys, we assess the capability of this approach to constrain dark energy parameters. We report this assessment in terms of the figure of merit (FoM) of the dark energy task force and in particular of the proposed Euclid mission which is particularly suited for this technique since it is a spectroscopic survey. The FoM due to stacked voids from the Euclid wide survey may double that of all other dark energy probes derived from Euclid data alone (combined with Planck priors). In particular, voids seem to outperform baryon acoustic oscillations by an order of magnitude. This result is consistent with simple estimates based on mode counting. The AP test based on stacked voids may be a significant addition to the portfolio of major dark energy probes and its potentialities must be studied in detail.

Lavaux, Guilhem [Department of Physics, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Wandelt, Benjamin D. [UPMC Univ Paris 06, UMR 7095, Institut d'Astrophysique de Paris, 98 bis, boulevard Arago, 75014 Paris (France)

2012-08-01

306

Precision Cosmography with Stacked Voids  

NASA Astrophysics Data System (ADS)

We present a purely geometrical method for probing the expansion history of the universe from the observation of the shape of stacked voids in spectroscopic redshift surveys. Our method is an Alcock-Paczy?ski (AP) test based on the average sphericity of voids posited on the local isotropy of the universe. It works by comparing the temporal extent of cosmic voids along the line of sight with their angular, spatial extent. We describe the algorithm that we use to detect and stack voids in redshift shells on the light cone and test it on mock light cones produced from N-body simulations. We establish a robust statistical model for estimating the average stretching of voids in redshift space and quantify the contamination by peculiar velocities. Finally, assuming that the void statistics that we derive from N-body simulations is preserved when considering galaxy surveys, we assess the capability of this approach to constrain dark energy parameters. We report this assessment in terms of the figure of merit (FoM) of the dark energy task force and in particular of the proposed Euclid mission which is particularly suited for this technique since it is a spectroscopic survey. The FoM due to stacked voids from the Euclid wide survey may double that of all other dark energy probes derived from Euclid data alone (combined with Planck priors). In particular, voids seem to outperform baryon acoustic oscillations by an order of magnitude. This result is consistent with simple estimates based on mode counting. The AP test based on stacked voids may be a significant addition to the portfolio of major dark energy probes and its potentialities must be studied in detail.

Lavaux, Guilhem; Wandelt, Benjamin D.

2012-08-01

307

SBNR processor for stack filters  

Microsoft Academic Search

The signed binary number representation (SBNR) is used to reduce the number of PBF calculation stages in stack filters. The approach is based on the possibility of minimization of signed power-of-two terms in the SBNR representation of input data. A coder and a decoder for the mutual transformation of binary-weighted code and the minimal SBNR are proposed. An efficient algorithm

David A. Akopian; Olli Vainio; Sos S. Agaian; Jaakko T. Astola

1997-01-01

308

Stack Monitor Operating Experience Review  

SciTech Connect

Stack monitors are used to sense radioactive particulates and gases in effluent air being vented from rooms of nuclear facilities. These monitors record the levels and types of effluents to the environment. This paper presents the results of a stack monitor operating experience review of the U.S. Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) database records from the past 18 years. Regulations regarding these monitors are briefly described. Operating experiences reported by the U.S. DOE and in engineering literature sources were reviewed to determine the strengths and weaknesses of these monitors. Electrical faults, radiation instrumentation faults, and human errors are the three leading causes of failures. A representative “all modes” failure rate is 1E-04/hr. Repair time estimates vary from an average repair time of 17.5 hours (with spare parts on hand) to 160 hours (without spare parts on hand). These data should support the use of stack monitors in any nuclear facility, including the National Ignition Facility and the international ITER project.

L. C. Cadwallader; S. A. Bruyere

2009-05-01

309

Two-component molecular crystals composed of chloronitrobenzoic acids and 4-aminopyridine.  

PubMed

The crystal structures of the four isomeric organic salts 4-aminopyridinium 2-chloro-4-nitrobenzoate, (I), 4-aminopyridinium 2-chloro-5-nitrobenzoate, (II), 4-aminopyridinium 5-chloro-2-nitrobenzoate, (III), and 4-aminopyridinium 4-chloro-2-nitrobenzoate, (IV), all C(5)H(7)N(2)+ x C(7)H(3)ClNO(4)-, are presented. Compound (I) has one intramolecular hydrogen bond, one intermolecular C-H* * *O hydrogen bond and pi-pi-stacking interactions. Compound (II) has N-H* * *O, C-H* * *O and C-H* * *Cl hydrogen bonds, and Cl* * *O-C electrostatic interactions. Compound (III) has N-H* * *O and C-H* * *O hydrogen bonds. Compound (IV) has a pi-pi-stacking interaction, but no C-H* * *O hydrogen bonds. PMID:11932555

Sugiyama, Teruki; Meng, Jiben; Matsuura, Teruo

2002-04-01

310

Boston Harbor sewage stack (for microcomputers). Software  

SciTech Connect

The Boston Harbor Sewage Stack is interactive educational computer program about how municipalities deal with sewage, how sewage systems work, non point pollution, and what citizens can do to help - focusing on Boston Harbor and the Boston Harbor Cleanup. The program is written at a level accessible to middle-school students, but with enough depth for adults. Schools and environmental organizations, especially in coastal areas, will find this program a useful addition to their environmental education offerings. The program shows what happens to sewage - from the moment of flush to its passage through the Massachusetts Water Resources Authority's sewage system and into Boston Harbor - now and as the cleanup proceeds. Users encounter topics for exploration, including storm sewers and combined sewer overflows (CSOs); non point pollution from pets, spilled waste oil, lawn and garden chemicals, and other sources; what not to flush and why; how officials can tell if water is polluted; and why it all matters.

Not Available

1992-12-01

311

A Systematic Study of Noncovalent Interactions Between Polymers and Carbon Nanotubes via Molecular Dynamics Simulations  

NASA Astrophysics Data System (ADS)

Molecular dynamics simulations were used to study the noncovalent interactions between a zig-zag single-walled carbon nanotube (SWCNT) and polymer chains with varying degrees of saturation, aromaticity, and aliphaticity. The simulations indicate that polymers with both flexible and rigid backbones tend to wrap around the SWCNT, although in different conformations. Flexible backbones wrap in random conformations, which are dependent upon the aliphatic lengths along the backbone and the presence of chemical groups like carbonyls. Polymers with unsaturation along the backbones tend to have more distinct wrapping conformations, as did polyamides with large alkane portions in the monomer unit such as nylon-12. Polymers with bulky and aromatic side groups such as polymethylmethacrylate (PMMA) and polystyrene (PS) prefer intrachain interactions rather than wrap the SWCNT, although PS showed some pi-pi interactions with the SWCNT. Other trends and the correlation of the physical chemical features to the properties of nanocomposites will be discussed.

Pasquinelli, Melissa; Tallury, Syamal

2010-03-01

312

A Cloudy Quark Bag Model of S, P, and D wave interactions for the coupled channel antikaon-nucleon system  

SciTech Connect

The Cloudy Quark Bag Model is extended from S-wave to P- and D-wave. The parameters of the model are determined by K{sup {minus}}p scattering cross section data, K{sup {minus}}p {yields}{Sigma}{pi}{pi}{pi} production data, K{sup {minus}}p threshold branching ratio data, and K{sup {minus}}p {yields}{Lambda}{pi}{pi}{pi} production data. The resonance structure of the {Lambda}(1405), {Sigma}(1385), and {Lambda}(1520) are studied in the model. The shift and width of kaonic hydrogen are calculated using the model.

He, Guangliang.

1992-05-15

313

Lightweight Stacks of Direct Methanol Fuel Cells  

NASA Technical Reports Server (NTRS)

An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

Narayanan, Sekharipuram; Valdez, Thomas

2004-01-01

314

Analyzing Stack Flows to Compare Java Programs  

NASA Astrophysics Data System (ADS)

This paper presents a method for comparing and detecting clones of Java programs by analyzing program stack flows. A stack flow denotes an operational behavior of a program by describing individual instructions and stack movements for performing specific operations. We analyze stack flows by simulating the operand stack movements during execution of a Java program. Two programs for detection of clones of Java programs are compared by matching similar pairs of stack flows in the programs. Experiments were performed on the proposed method and compared with the earlier approaches of comparing Java programs, the Tamada, k-gram, and stack pattern based methods. Their performance was evaluated with real-world Java programs in several categories collected from the Internet. The experimental results show that the proposed method is more effective than earlier methods of comparing and detecting clones of Java programs.

Lim, Hyun-Il; Han, Taisook

315

Novel silver-containing supramolecular frameworks constructed by combination of coordination bonds and supramolecular interactions.  

PubMed

The hydrothermal reactions of AgNO(3), 4,4'-bipy, and carboxylate ligands gave rise to three supramolecular architectures, namely [Ag(bipy)].H(2)SIPA.1/2bipy.H(2)O (1), [Ag(bipy)].1/2H(2)btec.H(2)O (2), and [Ag(bipy)](2).H(2)dpstc.2H(2)O (3) (H(3)SIPA = 5-sulfoisophthalic acid, bipy = 4,4'-bipyridine, H(4)btec = 1,2,4,5-benzenetetracarboxylic acid, H(4)dpstc = 3,3',4,4'-tetracarboxydiphenyl sulfone). All complexes are extended from Ag-bipy linear chains by the combination of coordination bonds and supramolecular interactions in two different approaches. Complexes 1 and 3 comprise two-dimensional frameworks. In the two complexes, a one-dimensional ladderlike structure is first formed by the connection of a Ag-bipy chain through hydrogen bonding between a free carboxylate/bipy ligand and weak coordinative interactions between a free carboxylate ligand and silver ion. The ladderlike structure is then extended to a two-dimensional layer architecture by pi...pi interactions between bipy ligands of the Ag-bipy chains. Complex 2 possesses a three-dimensional framework. The free H(2)btec(2)(-) ligands form a two-dimensional layer network by hydrogen-bonding interactions between protonated and deprotonated carboxylate groups; meanwhile, pi.pi interactions between bipy ligands of Ag-bipy chains also result in a two-dimensional layer. The two layers are further connected by weak Ag-O interactions to generate a three-dimensional supramolecular structure. PMID:14606846

Sun, Daofeng; Cao, Rong; Sun, Yanqiong; Bi, Wenhua; Li, Xiaoju; Wang, Yanqin; Shi, Qian; Li, Xing

2003-11-17

316

Stacking and Hydrogen Bonding. DNA Cooperativity at Melting  

Microsoft Academic Search

By taking into account base-base stacking interactions we improve the\\u000aGeneralized Model of Polypeptide Chain (GMPC). Based on a one-dimensional\\u000aPotts-like model with many-particle interactions, the GMPC describes the\\u000ahelix-coil transition in both polypeptides and polynucleotides. In the\\u000aframework of the GMPC we show that correctly introduced nearest-neighbor\\u000astacking interactions against the background of hydrogen bonding lead to\\u000aincreased stability

Vladimir F. Morozov; Artem V. Badasyan; Arsen V. Grigoryan; Mihran A. Sahakyan; Evgeni Sh. Mamasakhlisov

2004-01-01

317

Hydrogen Embrittlement And Stacking-Fault Energies  

NASA Technical Reports Server (NTRS)

Embrittlement in Ni/Cu alloys appears related to stacking-fault porbabilities. Report describes attempt to show a correlation between stacking-fault energy of different Ni/Cu alloys and susceptibility to hydrogen embrittlement. Correlation could lead to more fundamental understanding and method of predicting susceptibility of given Ni/Cu alloy form stacking-fault energies calculated from X-ray diffraction measurements.

Parr, R. A.; Johnson, M. H.; Davis, J. H.; Oh, T. K.

1988-01-01

318

Sorting with Complete Networks of Stacks  

Microsoft Academic Search

Knuth introduced the problem of sorting numbers using a sequence of stacks. Tarjan extended this idea to sorting with acyclic\\u000a networks of stacks (and queues), where items to be sorted move from a source through the network to a sink while they may\\u000a be stored temporarily at nodes (the stacks). Both characterized which permutations are sortable this way; but they

Felix G. König; Marco E. Lübbecke

2008-01-01

319

Optical properties of polarons in stacked quantum dots  

NASA Astrophysics Data System (ADS)

We present a theoretical investigation of the optical properties of polaronic excitons in stacked self-assembled quantum dots, which is based on the non-adiabatic approach. A parallelepiped-shaped quantum dot is considered as a model for a self-assembled quantum dot in a stack. The exciton-phonon interaction is taken into account for all phonon modes specific for these quantum dots (bulk-like, half-space and interface phonons). We show that the coupling between stacked quantum dots can lead to a strong enhancement of the optical absorption in the spectral ranges characteristic for phonon satellites. For thermodynamic equilibrium luminescence of stacked quantum dots, non-adiabaticity of the exciton-phonon system is shown to result in a significant rise of the relative intensities of phonon sidebands with increasing temperature. This work has been supported by the GOA BOF UA 2000, IUAP, FWO-V projects G.0274.01N, G.0435.03, the WOG WO.025.99N (Belgium) and the European Commission GROWTH Programme, NANOMAT project, contract No. G5RD-CT-2001-00545.

Gladilin, V. N.; Klimin, S. N.; Fomin, V. M.; Devreese, J. T.

2004-03-01

320

Study of the tau- ---> pi- pi- pi+ pi0 pi0 nu/tau and tau- --> 3h- 2h+ nu/tau Decays Using the BaBar Detector  

SciTech Connect

The {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup 0}{pi}{sup 0}{nu}{sub {tau}} and {tau}{sup -} {yields} 3h{sup -} 2h{sup +} {nu}{sub {tau}} decays have been studied using the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring. Preliminary branching fractions are given for the {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup 0}{pi}{sup 0}{nu}{sub {tau}} and to the sub-channels {tau}{sup -} {yields} {eta}{pi}{sup -} {pi}{sup 0}{nu}{sub {tau}} and {tau}{sup -} {yields} {omega}(782){pi}{sup -}{pi}{sup 0}{nu}{sub {tau}}. A preliminary upper limit is given on the branching fraction for the {phi}(1020){pi}{sup -}{pi}{sup 0}{nu}{sub {tau}} mode. In addition a preliminary measurement of the branching fraction of the {tau}{sup -} {yields} 3h{sup -}2h{sup +} {nu}{sub {tau}} decay (h = {pi}, K) is presented.

Sobie, R.; /Victoria U.

2005-06-21

321

A1 and A2 production in pi-p --> pi-pi-pi+p and pi-p --> pi-pi0pi0p reactions at 7.0 GeV\\/c  

Microsoft Academic Search

The A1 and A2 mesons as well as a varrhopi enhancement at 1230 MeV\\/c, the A (1230) are investigated. Both the A1 and A(1230) appear as small signals on a large Deck background, and like the background are produced very peripherally suggesting a diffractive process. Their JP are also consistent with diffractive production, the A1 being JP = 1+(l =

R. Morse; B. Y. Oh; W. D. Walker; T. F. Johnston; T. S. Yoon

1972-01-01

322

Stacked graphs--geometry & aesthetics.  

PubMed

In February 2008, the New York Times published an unusual chart of box office revenues for 7500 movies over 21 years. The chart was based on a similar visualization, developed by the first author, that displayed trends in music listening. This paper describes the design decisions and algorithms behind these graphics, and discusses the reaction on the Web. We suggest that this type of complex layered graph is effective for displaying large data sets to a mass audience. We provide a mathematical analysis of how this layered graph relates to traditional stacked graphs and to techniques such as ThemeRiver, showing how each method is optimizing a different "energy function". Finally, we discuss techniques for coloring and ordering the layers of such graphs. Throughout the paper, we emphasize the interplay between considerations of aesthetics and legibility. PMID:18988970

Byron, Lee; Wattenberg, Martin

2008-01-01

323

Analysis of stacked rotated gratings  

NASA Astrophysics Data System (ADS)

We study the rigorous design and analysis of stacked rotated gratings (SRGs) for novel photonic devices. A concept of sampling frequency is proposed to systematically design SRGs. With the help of a rectangular sampling lattice, we extend the standard 3D rigorous coupled-wave analysis (RCWA) algorithm to the analysis of SRGs. The resultant SRG-RCWA algorithm can be used to exactly analyze SRGs that have grating parameters that match the Fourier expansion represented by the sampling lattice. SRGs that do not fall in this category can often still be closely approximated with our approach. The SRG-RCWA algorithm has been successfully applied to the characterization of two fabricated SRGs that are designed to function as circular polarization filters for an IR imaging polarimetry system. The agreement between numerical SRG-RCWA results and experimental measurements demonstrates its validity and usefulness.

Jiang, Jianhua; Deguzman, Panfilo C.; Nordin, Gregory P.

2007-03-01

324

Closely stacked oligo(phenylene ethynylene)s: effect of ?-stacking on the electronic properties of conjugated chromophores.  

PubMed

In this work, a bicyclo[4.4.1]undecane scaffold is used to hold oligo(phenylene ethynylene) units in a cofacially stacked arrangement along the entire length of the conjugated units. We study the impact that the resulting strong interchain interactions have on the photophysical properties. The length of the individual oligomer branches was varied from three to five rings to investigate the effect of conjugation on the electronic properties of the stacked segments. Absorption and fluorescence spectra were recorded and compared to those of the corresponding unstacked analogues. Time-dependent density functional theory calculations were carried out and helped to rationalize the low-energy features present in the fluorescence spectra of the stacked systems. The calculations indicate that the low-energy emissions are due to the presence of excimer-like states. The stronger intensity of the low-energy fluorescence band observed in the five-ring stacked system compared to the three-ring analogue is attributed to the smaller activation barrier that separates the local intrachain state and the excimer-like state in the former compound. PMID:22455756

Jagtap, Subodh P; Mukhopadhyay, Sukrit; Coropceanu, Veaceslav; Brizius, Glen L; Brédas, Jean-Luc; Collard, David M

2012-04-25

325

A new all-round density functional based on spin states and S(N)2 barriers.  

PubMed

We report here a new empirical density functional that is constructed based on the performance of OPBE and PBE for spin states and S(N)2 reaction barriers and how these are affected by different regions of the reduced gradient expansion. In a previous study [Swart, Sola, and Bickelhaupt, J. Comput. Methods Sci. Eng. 9, 69 (2009)] we already reported how, by switching between OPBE and PBE, one could obtain both the good performance of OPBE for spin states and reaction barriers and that of PBE for weak interactions within one and the same (SSB-sw) functional. Here we fine tuned this functional and include a portion of the KT functional and Grimme's dispersion correction to account for pi-pi stacking. Our new SSB-D functional is found to be a clear improvement and functions very well for biological applications (hydrogen bonding, pi-pi stacking, spin-state splittings, accuracy of geometries, reaction barriers). PMID:19739845

Swart, Marcel; Solà, Miquel; Bickelhaupt, F Matthias

2009-09-01

326

Density functional theory investigations of titanium ?-surfaces and stacking faults  

NASA Astrophysics Data System (ADS)

Bulk properties of hcp-Ti, relevant for the description of dislocations, such as elastic constants, stacking faults and ?-surface, are computed using density functional theory (DFT) and two central force embedded atom interaction models (Zope and Mishin 2003 Phys. Rev. B 68 024102, Hammerschmidt et al 2005 Phys. Rev. B 71 205409). The results are compared with previously published calculations, except pair potential calculations, which are not appropriate for the description of the metallic bond. The comparison includes N-body central force (NB-CF) and N-body angular (NB-A) empirical potentials, tight-binding approximation to the electronic structure (TB), DFT pseudopotential (DFT-P) and all electron (DFT-A) calculations. None of the considered interaction models are fully satisfactory for the description of these properties. In particular, NB-CF, NB-A and TB interaction models are unable to describe the softening of the easy prismatic ?-surface leading to the appearance of a metastable stacking fault, as evidenced in all the DFT calculations. Most often, when the basal stacking fault excess energy is underevaluated, this leads to an inversion of the energetic stability between the I2 basal and the prismatic easy stacking faults. Even the DFT-pseudopotential calculations need to be improved regarding the description of the shear elastic constants. The implications of these results on the core structure and gliding properties of the a/3\\,\\langle1 1\\, \\bar{2}\\, 0\\rangle screw dislocation are analyzed. The calculated dissociation lengths into Shockley partials in both the basal and prismatic planes for the different models compare well with the measured ones in the corresponding simulations of the dislocation core structure when available. Finally, the Peierls stress is also evaluated using the Peierls-Nabarro model and compared with the experimentally measured one.

Benoit, Magali; Tarrat, Nathalie; Morillo, Joseph

2013-01-01

327

Refractive index sensing utilizing photonic crystal nano-beam cavity with slotted stack  

NASA Astrophysics Data System (ADS)

Two types of optical sensor based on one-dimensional Photonic Crystal (PhC) stack nanobeam cavity has been designed, fabricated and characterized. One-dimensional PhC stack nanobeam cavity with measured Q-factors up to 27000 and a sensitivity of 270nm/RIU has been demonstrated. Then, we introduce a finite width slot between two periodic arrays of the dielectric stacks. Thus, the majority of optical field distributes in the slotted low-index area and the light matter interaction with the analytes has been enhanced. A sensitivity of 410nm/RIU has been achieved while maintaining the Q-factors near 104.

Xu, Peipeng; Yao, Kaiyuan; Zheng, Jiajiu; Guan, Xiaowei; Shi, Yaocheng

2014-03-01

328

Local conformational variations observed in B-DNA crystals do not improve base stacking: computational analysis of base stacking in a d(CATGGGCCCATG)(2) B<-->A intermediate crystal structure.  

PubMed

The crystal structure of d(CATGGGCCCATG)(2) shows unique stacking patterns of a stable B<-->A-DNA intermediate. We evaluated intrinsic base stacking energies in this crystal structure using an ab initio quantum mechanical method. We found that all crystal base pair steps have stacking energies close to their values in the standard and crystal B-DNA geometries. Thus, naturally occurring stacking geometries were essentially isoenergetic while individual base pair steps differed substantially in the balance of intra-strand and inter-strand stacking terms. Also, relative dispersion, electrostatic and polarization contributions to the stability of different base pair steps were very sensitive to base composition and sequence context. A large stacking flexibility is most apparent for the CpA step, while the GpG step is characterized by weak intra-strand stacking. Hydration effects were estimated using the Langevin dipoles solvation model. These calculations showed that an aqueous environment efficiently compensates for electrostatic stacking contributions. Finally, we have carried out explicit solvent molecular dynamics simulation of the d(CATGGGCCCATG)(2) duplex in water. Here the DNA conformation did not retain the initial crystal geometry, but moved from the B<-->A intermediate towards the B-DNA structure. The base stacking energy improved in the course of this simulation. Our findings indicate that intrinsic base stacking interactions are not sufficient to stabilize the local conformational variations in crystals. PMID:11121480

Poner, J; Florián, J; Ng, H L; Poner, J E; Packová, N

2000-12-15

329

Opacity of Nitrogen Dioxide Stack Plumes.  

National Technical Information Service (NTIS)

Removal of the NO sub 2 from process off-gases would enable the Purex Plant to comply with the opacity standards for air pollution control. However, a relationship between stack opacity and NO sub 2 content of the stack gases is needed in order to impleme...

C. J. Evoniuk

1979-01-01

330

Thyristor stack for pulsed inductive plasma generation  

Microsoft Academic Search

A thyristor stack for pulsed inductive plasma generation has been developed and tested. The stack design includes a free wheeling diode assembly for current reversal. Triggering of the device is achieved by a high side biased, self supplied gate driver unit using gating energy derived from a local snubber network. The structure guarantees a hard firing gate pulse for the

C. Teske; J. Jacoby; W. Schweizer; J. Wiechula

2009-01-01

331

Effective Stack Design in Air Pollution Control.  

ERIC Educational Resources Information Center

Stack design problems fall into two general caterories--(1) those of building re-entry, and (2) those of general area pollution. Extensive research has developed adequate information, available in the literature, to permit effective stack design. A major roadblock to effective design has been the strong belief by architects and engineers that high…

Clarke, John H.

1968-01-01

332

catena-Poly[[[4-amino-3,5-bis(pyridin-2-yl)-4H-1,2,4-triazole-?(2)N(1),N(5)](dicyanamido-?N)copper(II)]-?2-dicyanamido-?(2)N:N']: coordination polymer chains linked into a bilayer by hydrogen bonds and ?-? stacking interactions.  

PubMed

In the title compound, [Cu(C2N3)2(C12H10N6)]n or [Cu(dca)2(abpt)]n, where abpt is 4-amino-3,5-bis(pyridin-2-yl)-4H-1,2,4-triazole and dca is the dicyanamide anion, the Cu(II) centre is five-coordinate with an approximately square-pyramidal geometry. One of the two dicyanamide ligands is a terminal ligand, but the other one acts as a ?1,5-bridging ligand between pairs of Cu(II) centres, so generating a one-dimensional coordination polymer. A combination of N-H···N and C-H···N hydrogen bonds, augmented by ?-? stacking interactions, links the coordination polymer chains into a bilayer structure. Comparisons are made with some related Cu(II) complexes containing dca ligands and heteroaromatic co-ligands. PMID:24705048

Setifi, Zouaoui; Setifi, Fatima; Saadi, Mohamed; Rouag, Djamil Azzeddine; Glidewell, Christopher

2014-04-01

333

Modular fuel-cell stack assembly  

DOEpatents

A fuel cell assembly having a plurality of fuel cells arranged in a stack. An end plate assembly abuts the fuel cell at an end of said stack. The end plate assembly has an inlet area adapted to receive an exhaust gas from the stack, an outlet area and a passage connecting the inlet area and outlet area and adapted to carry the exhaust gas received at the inlet area from the inlet area to the outlet area. A further end plate assembly abuts the fuel cell at a further opposing end of the stack. The further end plate assembly has a further inlet area adapted to receive a further exhaust gas from the stack, a further outlet area and a further passage connecting the further inlet area and further outlet area and adapted to carry the further exhaust gas received at the further inlet area from the further inlet area to the further outlet area.

Patel, Pinakin (Danbury, CT)

2010-07-13

334

Wind induced vibration of a stack  

SciTech Connect

A stack supported by guy wires at four levels is subjected to large-amplitude oscillations when the wind speed is over 15 m/s. The excitation mechanisms are identified based on scoping calculations, analytical prediction using a finite element code, and observation of the stack/wire response. The stack is determined to be excited by vortex shedding. Once lock-in resonance occurs, the guy wires are excited by the transverse motion of the stack. Large-amplitude oscillations of the guy wires are due to parametric resonance. Several methods are recommended to alleviate vibrational problem for short-term and long-term solutions. A new stack which is modified based on the results of this study is not subjected to any unacceptable oscillations.

Chen, S.S.; Cai, Y.

1992-01-01

335

Wind induced vibration of a stack  

SciTech Connect

A stack supported by guy wires at four levels is subjected to large-amplitude oscillations when the wind speed is over 15 m/s. The excitation mechanisms are identified based on scoping calculations, analytical prediction using a finite element code, and observation of the stack/wire response. The stack is determined to be excited by vortex shedding. Once lock-in resonance occurs, the guy wires are excited by the transverse motion of the stack. Large-amplitude oscillations of the guy wires are due to parametric resonance. Several methods are recommended to alleviate vibrational problem for short-term and long-term solutions. A new stack which is modified based on the results of this study is not subjected to any unacceptable oscillations.

Chen, S.S.; Cai, Y.

1992-12-01

336

Fire extinguishing attachment for chimney stacks  

SciTech Connect

A fire extinguishing attachment including a bracket for mounting on a stove stack and having a tubular guide therethrough. The tubular guide is an elbow tube having an inner end within the stack directed towards the chimney flue and an outer end outside the stack adapted to receive the nozzle of a powder type fire extinguisher. When a chimney fire occurs, the extinguisher is placed over the outer end of the guide end and activated. The powdered material is directed, by the guide, into the stack and up the chimney to the location of the fire thereby extinguishing the fire. The guide and bracket is preferably downstream of the damper in the same section of stack to be close to the chimney, and for unobstructed flow.

Sawtelle, K.

1984-11-13

337

Modeling theta-theta Interactions with the Effective Fragment Potential Method: The Benzene Dimer and Substituents  

SciTech Connect

This study compares the results of the general effective fragment potential (EFP2) method to the results of a previous combined coupled cluster with single, double, and perturbative triple excitations [CCSD(T)] and symmetry-adapted perturbation theory (SAPT) study [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690] on substituent effects in {pi}-{pi} interactions. EFP2 is found to accurately model the binding energies of the benzene-benzene, benzene-phenol, benzene-toluene, benzene-fluorobenzene, and benzene-benzonitrile dimers, as compared with high-level methods [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690], but at a fraction of the computational cost of CCSD(T). In addition, an EFP-based Monte Carlo/simulated annealing study was undertaken to examine the potential energy surface of the substituted dimers.

Toni Smithl; Lyudmila V. Slipchenko; Mark S. Gordon

2008-02-27

338

Barrier RF stacking at Fermilab  

SciTech Connect

A key issue to upgrade the luminosity of the Tevatron Run2 program and to meet the neutrino requirement of the NuMI experiment at Fermilab is to increase the proton intensity on the target. This paper introduces a new scheme to double the number of protons from the Main Injector (MI) to the pbar production target (Run2) and to the pion production target (NuMI). It is based on the fact that the MI momentum acceptance is about a factor of four larger than the momentum spread of the Booster beam. Two RF barriers--one fixed, another moving--are employed to confine the proton beam. The Booster beams are injected off-momentum into the MI and are continuously reflected and compressed by the two barriers. Calculations and simulations show that this scheme could work provided that the Booster beam momentum spread can be kept under control. Compared with slip stacking, a main advantage of this new method is small beam loading effect thanks to the low peak beam current. The RF barriers can be generated by an inductive device, which uses nanocrystal magnet alloy (Finemet) cores and fast high voltage MOSFET switches. This device has been designed and fabricated by a Fermilab-KEK-Caltech team. The first bench test was successful. Beam experiments are being planned.

Weiren Chou et al.

2003-06-04

339

Study of charmonium resonances in the gg -> K0SK pi- and gg -> K K-pi pi-pi0 processes  

SciTech Connect

This thesis reports the analysis of the e{sup +}e{sup -} {yields} e{sup +}e{sup -}K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} and e{sup +}e{sup -} {yields} e{sup +}e{sup -}K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0} processes using the final dataset of the BABAR experiment located at the SLAC National Accelerator Laboratory. From previous measurements, the K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} final state is known to show a clear signal from the {eta}{sub c}(2S) particle. This c{bar c} state escaped detection for almost twenty years and its properties are still not well established on the experimental ground, while accurate predictions exist on the theoretical side. The e{sup +}e{sup -} {yields} e{sup +}e{sup -}K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0} process is first studied in this thesis. An accurate determination of the {eta}{sub c}(2S) properties is obtained in the K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} decay mode. We also report the first observation of {eta}{sub c}(2S) and other charmonium states to the K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0} final state. The results of this thesis have been published in Physical Review D, and will be useful to test theoretical models describing the charmonium system. The thesis is organized in four chapters. The first one gives a brief introduction of the theoretical models used to describe the charmonium system. The second one discuss the current status of conventional and exotic charmonium spectroscopy, reporting recent experimental results and their interpretation. The third Chapter is devoted to describe the BABAR experiment. The analysis technique and results are described in Chapter 4. Finally, conclusions from this analysis are drawn.

Biassoni, Pietro; /U. Milan, Dept. Phys.

2012-02-22

340

Measurement of the branching fraction ${\\mathcal{B}}(\\Lambda^0_b\\rightarrow \\Lambda^+_c\\pi^-\\pi^+\\pi^-)$ at CDF  

SciTech Connect

We report an analysis of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4 fb{sup -1} of integrated luminosity. We reconstruct the currently largest samples of the decay modes {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -} (with {Lambda}{sub c}(2595){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} (with {Lambda}{sub c}(2625){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} (with {Sigma}{sub c}(2455){sup ++} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}), and {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455)0{pi}{sup +}{pi}{sup -} (with {Sigma}{sub c}(2455)0 {yields} {Lambda}{sub c}{sup +}{pi}{sup -}) and measure the branching fractions relative to the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -} branching fraction. We measure the ratio {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/ {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -})=3.04 {+-} 0.33(stat){sub -0.55}{sup +0.70}(syst) which is used to derive {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})=(26.8{sub -11.2}{sup +11.9}) x 10{sup -3}.

Aaltonen, T.; /Helsinki Inst. of Phys.; Alvarez Gonzalez, B.; /Oviedo U. /Cantabria Inst. of Phys.; Amerio, S.; /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U. /Fermilab; Annovi, A.; /Frascati; Antos, J.; /Comenius U.; Apollinari, G.; /Fermilab; Appel, J.A.; /Fermilab; Arisawa, T.; /Waseda U.; Artikov, A.; /Dubna, JINR /Texas A-M

2011-12-01

341

Study of the doubly and singly Cabibbo suppressed decays D+ --> K+ pi- pi+ and D(s)+ --> K+ pi- pi+ in the FOCUS experiment  

SciTech Connect

This thesis illustrates a complete study of the doubly and singly Cabibbo suppressed decays D{sup +} and D{sub s}{sup +} {yields} K{sup +} {pi}{sup -}{pi}{sup +}. Data for this analysis have been collected by the fixed-target high-energy photoproduction experiment FOCUS at Fermilab. The authors have selected the D{sup +} and D{sub s}{sup +} samples with cuts to obtain a sufficiently high statistics, a good signal to noise ratio and, at the same time, eliminate possible contaminations from the more copious and favored decays. The D{sup +} yield consists of 189 {+-} 24 events, with a signal to noise ratio {approx} 1; the D{sub s}{sup +} yield is 567 {+-} 31 and the signal to noise ratio is {approx} 2.5. The authors have measured {Lambda}(D{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +}) = 0.0065 {+-} 0.0008 {+-} 0.004 and {Lambda}(D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.127 {+-} 0.007 {+-} 0.014, improving the previous determinations of a factor of 2 and 5, respectively. The author has also performed a Dalitz plot analysis for both decays. The amplitude analysis for D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +} represents the first available measurement for this channel.

Edera, Laura; /Milan U.

2005-01-01

342

First observation and measurement of the resonant structure of the lambda_b->lambda_c pi-pi+pi- decay mode  

SciTech Connect

The authors present the first observation of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay using data from an integrated luminosity of approximately 2.4 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. They also present the first observation of the resonant decays {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup 0} {pi}{sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} and {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, and measure their relative branching ratios.

Azzurri, P.; Barria, P.; Ciocci, M.A.; Donati, S.; Vataga, E.

2009-12-01

343

First Observation of the Cabibbo-suppressed Decays Xi+(c) ---> Sigma+ pi- pi+ and Xi+(c) ---> Sigma- pi+ pi+ and Measurement of their Branching Ratios  

SciTech Connect

The authors report the first observation of two Cabibbo-suppressed decay modes, {Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +} and {Xi}{sub c}{sup +} {yields} {Sigma}{sup -} {pi}{sup +}{pi}{sup +}. They observe 56 {+-} 13 over a background of 21, and 23 {+-} 7 over a background of 12 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c {Sigma}{sup -} beam. The branching ratios of the decays relative to the Cabibbo-favored {Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +} are measured to be B({Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +})/B({xi}{sub c}{sup +} {yields} {Xi}{sup -} {pi}{sup +}{pi}{sup +}) = 0.50 {+-} 0.20, and B({Xi}{sub c}{sup +} {yields} {Sigma}{sup -}{pi}{sup +}{pi}{sup +})/B({Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +}) = 0.23 {+-} 0.11, respectively. They also report branching ratios for the same decay modes of the {Lambda}{sub c}{sup +} relative to {Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}.

Vazquez-Jauregui, E.; /San Luis Potosi U.; Engelfried, J.; /San Luis Potosi U.; Akgun, U.; /Iowa U.; Alkhazov, Georgiy; /St. Petersburg, INP; Amaro-Reyes, J.; /San Luis Potosi U.; Atamantchouk, A.G.; /St. Petersburg, INP; Ayan, Ahmet Sedat; /Iowa U.; Balatz, M.Y.; /Moscow, ITEP; Blanco-Covarrubias, A.; /San Luis Potosi U.; Bondar, N.F.; /St. Petersburg, INP; Cooper, Peter S.; /Fermilab /Michigan U., Flint

2008-04-01

344

Breath stacking in children with neuromuscular disorders.  

PubMed

Respiratory muscle weakness in neuromuscular disorders (NMD) can lead to shallow breathing and respiratory insufficiency over time. Children with NMD often cannot perform maneuvers to recruit lung volume. In adults, breath stacking with a mask and one-way valve can achieve significantly increased lung volumes. To evaluate involuntary breath stacking (IBS) in NMD, we studied 23 children of whom 15 were cognitively aware and able to communicate verbally. For IBS, a one-way valve and pneumotachograph were attached to a face mask. Tidal volumes (Vt) and minute ventilation (VE ) were calculated from airflow over 30?sec before and after 15?sec of expiratory valve closure. Six cooperative male subjects with Duchenne muscular dystrophy (DMD) participated in a subsequent comparison of IBS with voluntary breath stacking (VBS) and supported breath stacking (SBS). The average Vt in those studied with IBS was 277?ml (range 29-598?ml). The average increase in volume by stacking was 599?ml (range -140 to 2,916?ml) above Vt . The average number of stacked breaths was 4.5 (range 0-17). VE increased on average by 18% after stacking (P?stacking. Four of the 23 children did not breath stack. Compared to IBS, VBS achieved similar volumes in the six subjects with DMD but SBS was more successful in those with greatest muscle weakness. IBS may achieve breath volumes of approximately three times Vt and may be particularly useful in non-cooperative subjects with milder degrees of respiratory muscle weakness. Pediatr Pulmonol. 2014; 49:544-553. © 2013 Wiley Periodicals, Inc. PMID:23956183

Jenkins, H M; Stocki, A; Kriellaars, D; Pasterkamp, H

2014-06-01

345

Subnanomolar inhibitor of cytochrome bc1 complex designed by optimizing interaction with conformationally flexible residues.  

PubMed

Cytochrome bc(1) complex (EC 1.10.2.2, bc(1)), an essential component of the cellular respiratory chain and the photosynthetic apparatus in photosynthetic bacteria, has been identified as a promising target for new drugs and agricultural fungicides. X-ray diffraction structures of the free bc(1) complex and its complexes with various inhibitors revealed that the phenyl group of Phe274 in the binding pocket exhibited significant conformational flexibility upon different inhibitors binding to optimize respective pi-pi interactions, whereas the side chains of other hydrophobic residues showed conformational stability. Therefore, in the present study, a strategy of optimizing the pi-pi interaction with conformationally flexible residues was proposed to design and discover new bc(1) inhibitors with a higher potency. Eight new compounds were designed and synthesized, among which compound 5c, with a K(i) value of 570 pM, was identified as the most promising drug or fungicide candidate, significantly more potent than the commercially available bc(1) inhibitors, including azoxystrobin (AZ), kresoxim-methyl (KM), and pyraclostrobin (PY). To our knowledge, this is the first bc(1) inhibitor discovered from structure-based design with a potency of subnanomolar K(i) value. For all of the compounds synthesized and assayed, the calculated binding free energies correlated reasonably well with the binding free energies derived from the experimental K(i) values, with a correlation coefficient of r(2) = 0.89. The further inhibitory kinetics studies revealed that 5c is a noncompetitive inhibitor with respect to substrate cytochrome c, but it is a competitive inhibitor with respect to substrate ubiquinol. Due to its subnanomolar K(i) potency and slow dissociation rate constant (k(-0) = 0.00358 s(-1)), 5c could be used as a specific probe for further elucidation of the mechanism of bc(1) function and as a new lead compound for future drug discovery. PMID:19928849

Zhao, Pei-Liang; Wang, Le; Zhu, Xiao-Lei; Huang, Xiaoqin; Zhan, Chang-Guo; Wu, Jia-Wei; Yang, Guang-Fu

2010-01-13

346

Slip stacking experiments at Fermilab main injector  

SciTech Connect

In order to achieve an increase in proton intensity, Fermilab Main Injector will use a stacking process called ''slip stacking''. The intensity will be doubled by injecting one train of bunches at a slightly lower energy, another at a slightly higher energy, then bringing them together for the final capture. Beam studies have started for this process and we have already verified that, at least for a low beam intensity, the stacking procedure works as expected. For high intensity operation, development work of the feedback and feedforward systems is under way.

Kiyomi Koba et al.

2003-06-02

347

Repetitively pulsed high power stacked Blumlein generators  

NASA Astrophysics Data System (ADS)

The stacked Blumlein pulse generators developed at the University of Texas at Dallas consist of several triaxial Blumleins stacked in series at one end. The lines are charged in parallel and synchronously commuted with a single switching element at the other end. In this way, relatively low charging voltages are multiplied to give the desired discharge voltage across an arbitrary load. Described here is the progress in development and characterization of these novel pulse-power generators capable of discharging at high repetition rates. The introduction of a tapered transmission line concept to the stacked Blumlein design provided fine tuning of output waveforms.

Davanloo, F.; Borovina, D. L.; Collins, C. B.; Agee, F. J.; Kingsley, L. E.

1995-05-01

348

Hydrogen Bonding and Stacking of DNA Bases: A Review of Quantum-chemical ab initio Studies  

Microsoft Academic Search

Ab initio quantum-chemical calculations with inclusion of electron correlation made since 1994 (such reliable calculations were not feasible before) significantly modified our view on interactions of nucleic acid bases. These calculations allowed to perform the first reliable comparison of the strength of stacked and hydrogen bonded pairs of nucleic acid bases, and to characterize the nature of the base-base interactions.

Ji?í Šponer; Jerzy Leszczynski; Pavel Hobza

1996-01-01

349

Wearable solar cells by stacking textile electrodes.  

PubMed

A new and general method to produce flexible, wearable dye-sensitized solar cell (DSC) textiles by the stacking of two textile electrodes has been developed. A metal-textile electrode that was made from micrometer-sized metal wires was used as a working electrode, while the textile counter electrode was woven from highly aligned carbon nanotube fibers with high mechanical strengths and electrical conductivities. The resulting DSC textile exhibited a high energy conversion efficiency that was well maintained under bending. Compared with the woven DSC textiles that are based on wire-shaped devices, this stacked DSC textile unexpectedly exhibited a unique deformation from a rectangle to a parallelogram, which is highly desired in portable electronics. This lightweight and wearable stacked DSC textile is superior to conventional planar DSCs because the energy conversion efficiency of the stacked DSC textile was independent of the angle of incident light. PMID:24789065

Pan, Shaowu; Yang, Zhibin; Chen, Peining; Deng, Jue; Li, Houpu; Peng, Huisheng

2014-06-10

350

40 CFR 61.44 - Stack sampling.  

Code of Federal Regulations, 2010 CFR

...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling. (a...days after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given...

2010-07-01

351

40 CFR 61.44 - Stack sampling.  

Code of Federal Regulations, 2010 CFR

...POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.44 Stack sampling. (a...days after samples are taken and before any subsequent rocket motor firing or propellant disposal at the given...

2009-07-01

352

Near-Earth Asteroid Stack - Mission Animation  

NASA Video Gallery

A possible stack configuration - a deep space habitat, the Orion Multi-Purpose Crew Vehicle and Space Exploration Vehicle - approaches a near-Earth asteroid. During a mission that could take months...

353

Evaluation Methodology Guidance for Stack Packages.  

National Technical Information Service (NTIS)

This report provides evaluation methodology guidance based on previous National Aeronautics and Space Administration (NASA) reports and literature surveys for 3D stack packages and assemblies. Two aspects of technology are covered: package itself (guidanc...

D. Gerke R. Ghaffarian

2009-01-01

354

On Understanding Stacking Fault Formation in Ice  

NASA Astrophysics Data System (ADS)

Despite dedicated efforts aimed at revealing possible molecular structures of the ice defects associated with stacking faults in ice (I), these molecular arrangements have remained a puzzle. Here we demonstrate how the reorganization of water molecules on different faces of ice (I) can facilitate formation of stacking faults within a crystal. We show that a pair of point defects can manifest a particular combination of coupled five- and eight-membered rings (5-8 rings). These structural motifs can facilitate a shift in layers within an ice (I) crystal, thereby inducing stacking faults. Furthermore, the presence of molecular solutes such as methane at the ice interface appears to trigger the formation of coupled 5-8 rings. The observation of such coupled 5-8 ring defects provides insights into the possible molecular mechanisms of stacking fault formation in ice (I) and has implications for ice crystal growth phenomenology and the consequent physical and chemical properties of ice.

Pirzadeh, Payman; Kusalik, Peter G.

2012-12-01

355

Development of Mechanically Stacked Tandem Concentrator Cells.  

National Technical Information Service (NTIS)

Mechanically stacked, multijunction (MSMJ) solar cells offer an excellent prospect for significantly increased efficiencies in the near term. In this work, we examine several new concepts for a MSMJ solar cell. These MSMJ cell concepts include the followi...

J. A. Cape L. M. Fraas P. S. McLeod L. D. Partain

1987-01-01

356

Photonic band gap of a graphene-embedded quarter-wave stack  

NASA Astrophysics Data System (ADS)

Here, we present a mechanism for tailoring the photonic band structure of a quarter-wave stack without changing its physical periods by embedding conductive sheets. Graphene is utilized and studied as a realistic, two-dimensional conductive sheet. In a graphene-embedded quarter-wave stack, the synergic actions of Bragg scattering and graphene conductance contributions open photonic gaps at the center of the reduced Brillouin zone that are nonexistent in conventional quarter-wave stacks. Such photonic gaps show giant, loss-independent density of optical states at the fixed lower-gap edges, of even-multiple characteristic frequency of the quarter-wave stack. The conductive sheet-induced photonic gaps provide a platform for the enhancement of light-matter interactions.

Fan, Yuancheng; Wei, Zeyong; Li, Hongqiang; Chen, Hong; Soukoulis, Costas M.

2013-12-01

357

PAH emission from various industrial stacks  

Microsoft Academic Search

The emission of polycyclic aromatic hydrocarbons (PAHs) from various industrial stacks (blast furnace, basic oxygen furnace, coke oven, electric arc furnace, heavy oil plant, power plant and cement plant) in southern Taiwan were investigated. PAH concentrations (?g\\/N m3) and PAH emission factors (?g\\/kg feedstock) were determined. In addition to these eight stationary industrial stacks, an industrial waste incinerator, a diesel

Hsi-Hsien Yang; Wen-Jhy Lee; Shui-Jen Chen; Soon-Onn Lai

1998-01-01

358

Cosmic ray test of INO RPC stack  

NASA Astrophysics Data System (ADS)

The India-based Neutrino Observatory (INO) collaboration is planning to build a 50 kt magnetised iron calorimeter (ICAL) detector using glass Resistive Plate Chambers (RPCs) as active detector elements. A stack of 12 such glass RPCs of 1 m ×1 m in area is tracking cosmic ray muons for over three years. In this paper, we will review the constructional aspects of the stack and discuss the performance of the RPCs using this cosmic ray data.

Bhuyan, M.; Datar, V. M.; Kalmani, S. D.; Lahamge, S. M.; Mondal, N. K.; Nagaraj, P.; Pal, S.; Reddy, L. V.; Redij, A.; Samuel, D.; Saraf, M. N.; Satyanarayana, B.; Shinde, R. R.; Verma, P.

2012-01-01

359

A study of the excited states in cytosine and guanine stacks in the Hartree-Fock and exciton approximations  

SciTech Connect

We report calculated exciton energies for the cytosine and guanine stacks obtained in the ab initio Hartree-Fock crystal orbital and exciton approximation, which includes the excited electron-hole interaction. This interaction plays an important role in the description of excited electron spectra in the low-energy region. The stacks were chosen as examples of polymers with helical symmetry. 21 refs., 3 figs., 3 tabs.

Grobelsek-Vracko, M.; Zaider, M. (College of Physicians and Surgeons of Columbia Univ., New York, NY (United States))

1994-04-01

360

The effect of anion–ligand ?-stacking interaction on silver(I) extraction by thiaoxa-macrocycles: A search for the evidences by X-ray and NMR approaches  

Microsoft Academic Search

S2Ox macrocyclic ligands with (L1: x=3 and L2: x=4) and without (L3: x=3 and L4: x=4) dibenzo-subunit were employed as extractants to clarify the anion–ligand interaction on the extraction efficiency of soft metal picrates. All of the ligands shows silver(I) selectivity and the silver picrate was more extractable with L1 and L2 when compared with L3 and L4. From the

Mi Ryoung Song; Ji-Eun Lee; So Young Lee; Joobeom Seo; Ki-Min Park; Shim Sung Lee

2006-01-01

361

Energy level alignment in Au/pentacene/PTCDA trilayer stacks  

NASA Astrophysics Data System (ADS)

Ultraviolet photoelectron spectroscopy is used to investigate the energy level alignment and molecular orientation at the interfaces in Au/pentacene/PTCDA trilayer stacks. We deduced a standing orientation for pentacene grown on Au while we conclude a flat lying geometry for PTCDA grown onto pentacene. We propose that the rough surface of polycrystalline Au induces the standing geometry in pentacene. It is further shown that in situ deposition of PTCDA on pentacene can influence the orientation of the surface pentacene layer, flipping part of the surface pentacene molecules into a flat lying geometry, maximizing the orbital interaction across the pentacene-PTCDA heterojunction.

Sehati, P.; Braun, S.; Fahlman, M.

2013-09-01

362

Hydrogen effects on crystal dislocations and stacking-fault energy  

NASA Astrophysics Data System (ADS)

The mechanisms of hydrogen shielding the interaction of dislocations with other elastic centers are outlined. In-situ straining transmission electron microscope experiments show that the effect of hydrogen on the interaction between dislocations is reversible, whereas in systems where significant levels of impurities exist, the effect of hydrogen is to decrease the interaction between dislocations and solute atoms. Both observations strongly support the HELP mechanism to account for the observed hydrogen-enhanced dislocation mobility. In addition, the effect of hydrogen on the nature (screw vs. edge) of dislocations in high-purity aluminum are discussed. Hydrogen stabilizes the edge dislocation segments which results in a decreased ability of dislocations to cross-slip. It suggests that hydrogen has a tendency to promote slip planarity. Finally, the effect of hydrogen on the stacking-fault energy of an austenitic stainless steel is presented. Measurements done on dislocation nodes reveal a reduction of approximately 19% when comparing the stacking fault energies in vacuum and 40 torr of hydrogen.

Ferreira, Paulo Jorge

363

Manifold gasket accommodating differential movement of fuel cell stack  

DOEpatents

A gasket for use in a fuel cell system having at least one externally manifolded fuel cell stack, for sealing the manifold edge and the stack face. In accordance with the present invention, the gasket accommodates differential movement between the stack and manifold by promoting slippage at interfaces between the gasket and the dielectric and between the gasket and the stack face.

Kelley, Dana A. (New Milford, CT); Farooque, Mohammad (Danbury, CT)

2007-11-13

364

Observation of exclusively ?-stacked heterodimer of indole and hexafluorobenzene in the gas phase  

NASA Astrophysics Data System (ADS)

In this study, the structure of the indole . . . hexafluorobenzene dimer has been investigated in the gas phase by using resonant two photon ionzation (R2PI) and IR-UV double resonance spectroscopy combined with quantum chemistry calculations. We have confirmed the presence of exclusively ?-stacked structure of the dimer from both experimental and theoretical IR spectra in the N-H stretching region. Observation of a single stable structure of the dimer has also been verified through 3D potential energy surface scan of the ?-stacked dimer by varying the parallel displacement of the hexafluorobenzene unit simultaneously along the major and minor axes of the indole moiety. ?-stacking interaction is present very often between the tryptophan and phenylalanine residues in proteins. But this interaction has not been observed earlier in the gas phase experiment by studying indole . . . benzene dimer because the N-H group of indole predominately directs towards the N-H . . . ? hydrogen bonded T-shaped structure. The chosen molecular systems in this study not only rule out the possibility of the formation of the N-H . . . ? bound T-shaped dimer but also enable the determination of the structure by probing the N-H group. The ?-stacked indole . . . hexafluorobenzene dimer has a unique structure where the center of the hexafluorobenznene ring is aligned with the center of the shared bond of the indole ring. Our work provides useful insight in designing unnatural proteins having strong ?-stacking interaction between the tryptophan and phenylalanine residues.

Kumar, Sumit; Das, Aloke

2013-09-01

365

Do ?-? stacking interactions really play a role in the magnetic coupling mechanisms of [Cu2(?2-CH3COO)2L2(H2O)2]n+ (L = heterocyclic base, n = 0, 2) complexes? An ab initio inspection.  

PubMed

The magnetic properties of two bis-acetate binuclear copper(II) complexes, namely [Cu2(?2-CH3COO)2(bpydiol-H)2(H2O)2] (bpydiol-H = mono deprotonated 2,2'-bipyridine-3,3'-diol) and [Cu2(?2-CH3COO)2(phen)2(H2O)2](2+) (phen = 1,10-phenantroline), is revisited using ab initio wave function-based calculations (CASSCF, DDCI). Thanks to an analysis of the magnetic exchange coupling based on localized orbitals, it is shown that, unlike stated in the original work [C. Hou et al. Dalton Trans. 2008, 5970], ?-? interactions do not contribute to the overall antiferromagnetism character of these complexes. PMID:23808675

Bandeira, Nuno A G; Maynau, Daniel; Robert, Vincent; Le Guennic, Boris

2013-07-15

366

MTR STACK, TRA710, CONTEXTUAL VIEW AFTER ETR STACK HAD BEEN ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR STACK, TRA-710, CONTEXTUAL VIEW AFTER ETR STACK HAD BEEN DEMOLISHED. CAMERA FACING NORTHWEST. MTR BUILDING IS AT LEFT EDGE OF VIEW. INL NEGATIVE NO. HD52-1-4. Mike Crane, Photographer, 5/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

367

Smart stackingTM technology: An industrial solution for 3D layer stacking  

Microsoft Academic Search

Smart Stacking™ is a wafer-to-wafer stacking technology of partially or fully processed wafers. This technology enables transferring very thin layers in a high volume manufacturing environment. The core technologies are surface conditioning, low temperature direct bonding and wafer thinning (figure 1). This technology is adapted for advanced semiconductor applications such as Back Side Illumination (BSI) CMOS Image Sensors (CIS) as

C. Lagahe Blanchard; I. Radu; M. Sadaka; K. Landry

2011-01-01

368

Technical description of Stack 296-B-5  

SciTech Connect

Of particular concern to facilities on the Hanford site is Title 40, Code of Federal Regulations, Chapter 40, Part 61, Subpart H, ``National emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities.`` Assessments of facility stacks and potential radionuclide emissions determined whether these stacks would be subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. Stack 296-B-5 exhausts 221-BB building which houses tanks containing B Plant steam condensate and B Plant process condensate from the operation of the low-level waste concentrator. The assessment of potential radionuclide emissions from the 296-B-5 stack resulted in an effective dose equivalent to the maximally exposed individual of less than 0.1 millirem per year. Therefore, the stack is not subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. However, the sampling and monitoring system must be in compliance with the Environmental Compliance Manual, WHC-CM-7-5. Currently, 296-B-5 is sampled continuously with a record sampler and continuous air monitor (CAM).

Ridge, T.M.

1994-11-15

369

Inflatable containment diaphragm for sealing and removing stacks  

DOEpatents

A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

Meskanick, Gerald R. (Elizabeth, PA); Rosso, David T. (Pittsburgh, PA)

1993-01-01

370

Inflatable containment diaphragm for sealing and removing stacks  

DOEpatents

A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

Meskanick, G.R.; Rosso, D.T.

1993-04-13

371

DNA sequencing by hybridization to microchip octa-and decanucleotides extended by stacked pentanucleotides.  

PubMed Central

The efficiency of sequencing by hybridization to an oligonucleotide microchip grows with an increase in the number and in the length of the oligonucleotides; however, such increases raise enormously the complexity of the microchip and decrease the accuracy of hybridization. We have been developing the technique of contiguous stacking hybridization (CSH) to circumvent these shortcomings. Stacking interactions between adjacent bases of two oligonucleotides stabilize their contiguous duplex with DNA. The use of such stacking increases the effective length of microchip oligonucleotides, enhances sequencing accuracy and allows the sequencing of longer DNA. The effects of mismatches, base composition, length and other factors on the stacking are evaluated. C